secutive individuals diagnosed with high grade glioma (diffuse astrocytoma IDH-wild type n=2, ana... more secutive individuals diagnosed with high grade glioma (diffuse astrocytoma IDH-wild type n=2, anaplastic astrocytoma n=18, and glioblastoma n=28) between June 2017 and October 2018. Patients who underwent subtotal (n=30, 62.5%), partial (n=17, 35.4%) removal or biopsy (n=1, 2.1%) were included in this analysis for interpreting radio-sensitivity of residual tumor. We investigated mATM by NGS of FFPE specimens with a TruSight Tumor 170 (TST-170) cancer panel. RESULTS: Among 48 samples, mATM was detected in 17% of cases (n=8). There was no significant difference in patient or tumor characteristics. Among mATM patients, there were 5 patients with glioblastoma and 3 patients with anaplastic astrocytoma IDH-wildtype. Most mutation was missense mutation (n=7, 88%). Median variant allele frequency was 44.7% (Interquartile range, IQR, 10.5-59.9%). Median follow-up duration after radiotherapy was 11.4 (IQR, 8.0-15.8) months. Radiation-related change was observed in 34 patients (71%). Tumors with mATM were related to higher frequency of radiation-related change at 6 months than tumors without mATM, respectively (88% and 64%, p = 0.016). Cases with mATM exhibited significantly 1-year progression free survival (PFS, 100% vs. 54%, p = 0.036). On subgroup of IDH WT (n=39) known as poor prognostic molecular marker, patients with mATM showed significantly higher PFS than patients without mATM (p=0.016, 1yr PFS 100% vs 43%). On subgroup with subventricular zone involvement (n=38) representative of aggressiveness, PFS of patients with mATM was significantly higher than others (p=0.026, 1yr PFS 100% vs 43.9%). CONCLUSIONS: Our results demonstrated that mATM is involved in radio-sensitivity with immediate radiologic change after radiation therapy followed by favorable radiologic response and clinical outcome beyond the aggressive nature of high grade glioma.
The optimal timing of adjuvant chemoradiation after surgical resection of glioblastoma remains un... more The optimal timing of adjuvant chemoradiation after surgical resection of glioblastoma remains unknown. The National Cancer Database was queried for all patients diagnosed with glioblastoma from 2004 to 2012 who underwent surgical resection followed by adjuvant chemoradiation. Cox proportional hazards modeling was used to determine factors influencing survival. Optimal thresholds for time to initiation (TTI) of adjuvant therapy were determined using recursive partitioning analysis (RPA). A total of 16,335 patients were included. The RPA model identified an optimal threshold of 61 days to initiation of adjuvant therapy which was confirmed with randomly selected training and validation sets using conditional inference trees repeated 1000 times for robustness. Compared to patients who initiated adjuvant therapy within 61 days (median overall survival: 14.1 months, 95% CI 13.8-14.3 months), patients who initiated adjuvant therapy after day 61 (MOS: 12.0, CI: 10.7-12.9) had higher risk of death (p < 0.0001). For patients with glioblastoma, large increases in time to the initiation of adjuvant therapy leads to inferior survival with a threshold of 61 days or less following surgical resection.
International Journal of Radiation Oncology Biology Physics, Feb 1, 2001
Methods and Materials: From April 1998 to December 1999, 40 postprostatectomy patients were treat... more Methods and Materials: From April 1998 to December 1999, 40 postprostatectomy patients were treated with intensity modulated radiation therapy (IMRT) to a median prescribed dose of 64 Gy (mean dose of 69 Gy). The Radiation Therapy Oncology Group (RTOG) scoring ...
Intraoperative magnetic resonance imaging (iMRI) is a useful adjunct for resection of primary mal... more Intraoperative magnetic resonance imaging (iMRI) is a useful adjunct for resection of primary malignant brain tumors (MBTs). The aim of our study is to investigate the impact of iMRI on health care utilization in patients who underwent craniotomy for resection of MBTs. MarketScan database were queried using the ICD-9/10 and CPT 4th edition, from 2008 to 2020. We included patients ≥ 18 years of age who underwent a craniotomy with at-least one year follow-up. Outcomes were length of stay (LOS), discharge disposition, hospital/emergency room (ER) re-admissions, outpatient services, medication re lls and corresponding payments. Of 6,640 patients who underwent craniotomy for MBTs, 465 patients (7%) had iMRI used during the procedure with 0.7% per year increase in iMRI use during the study period. Patients without iMRI use had higher complications at index hospitalization compared to those with iMRI use (19% vs 14%, p = 0.04). There was no difference in the ER admission rates among the patients who underwent surgery with and without iMRI use at 6-months and 1-year after the index procedure. In terms of post-discharge payments, no signi cant differences were noted among the patients without and with iMRI use at 6-months
NEURO-ONCOLOGY • NOVEMBER 2018 received prior chemotherapy before salvage surgery and RT. Overall... more NEURO-ONCOLOGY • NOVEMBER 2018 received prior chemotherapy before salvage surgery and RT. Overall, the 10-year PFS and OS were 52% and 65%, respectively. On multivariable analysis, lower KPS (HR:0.96, 95% CI:0.93-0.99), gliomatosis (HR:195, 95% CI:16-2340), and prior chemotherapy (HR:2.2, 95% CI:1.04-4.7) were the only significant factors associated with worse PFS; notably, age, grade, and EOR were not significant for PFS. In a subset of 146 patients excluding those with gliomatosis and prior chemotherapy, age >40, grade 3, subtotal resection, TMZ chemotherapy, and lower RT dose were not associated with worse PFS or OS rates (all p >0.05). CONCLUSIONS: Oligodendrogliomas with 1p/19q codeletion have favorable outcomes after RT, except those with gliomatosis or prior chemotherapy exposure. Traditional prognostic factors of age >40, EOR, and grade do not appear to reliably risk stratify these patients after adjuvant RT. Their use to guide treatment selection may need to be revisited.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2009
comparing both the measured dose profile and the isodose lines with those calculated by the Eclip... more comparing both the measured dose profile and the isodose lines with those calculated by the Eclipse TPS. It is possible to test the consistency of the delivered dose from spots with 58 different energies in one exposure by using the step phantom with MatriXX. Conclusions: The 2-D ion chamber array was found to be useful for quick real time QA checks of both the spot positioning accuracy and the consistency of dose delivery by multiple spots with different energies from a spot scanning proton therapy machine. All or some of the procedures explored in this study can become part of a periodic QA program for these machines.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2015
Results: Thirty-two patients (27%) quit smoking after SBRT, and 87 patients (73%) continued smoki... more Results: Thirty-two patients (27%) quit smoking after SBRT, and 87 patients (73%) continued smoking. Median follow-up was 22 months (range 2-87 months). Patients being treated for their first malignancy were twice as likely to quit smoking after SBRT as those with a prior malignancy, 35% vs. 18% (p Z 0.038). On univariate analysis, smoking status after treatment, age-adjusted Charlson comorbidity score, tumor size, and squamous histology were predictive of worse OS. The prior number of cigarette packyears was not significant in this population of patients still smoking at the time of treatment (p Z 0.62). On multivariate analysis, smoking status (HR 2.1, p Z 0.045), age-adjusted Charlson comorbidity score, and tumor size remained significant predictors of worse OS. In a Kaplan-Meier comparison, smoking cessation after SBRT was associated with an increase in 2-year OS, 78% vs. 69% (p Z 0.014). There was no difference in progression free survival (p Z 0.23) and local control (p Z 0.63) between the two groups. Conclusion: Overall survival is significantly improved in patients who can stop smoking after SBRT for early stage NSCLC, no matter their previous smoking history. Given this overall survival benefit, encouraging smoking cessation should be an important part of every post-treatment visit.
ABSTRACT Purpose: Proton therapy is an emerging treatment modality for pediatric cancer patients ... more ABSTRACT Purpose: Proton therapy is an emerging treatment modality for pediatric cancer patients because of its advantageous depth‐dose relationship. Although proton dose distributions conform to the target volume, stray neutrons deliver low doses to healthy tissues throughout the body. These exposures may increase the risk of radiation carcinogenesis, particularly for pediatric patients. The aim of this study was to quantify stray radiation dose for a pediatric patient receiving proton craniospinal irradiation and to evaluate methods of reducing stray radiation dose to the patient. Method and Materials: Equivalent dose to each organ and effective dose from stray radiation was estimated for a 30.6 Gy craniospinal treatment using Monte Carlo simulations of a passively‐scattered proton nozzle and a human phantom. The treatment plan and phantom were based on CT images of a 10‐year‐old boy treated for medulloblastoma. Comparisons were made between the existing nozzle, an idealized nozzle with no stray radiation, and the existing nozzle with modest modifications to suppress stray radiation. The existing nozzle was modified by increasing the distance from the patient to the primary external neutron source and enhancing the local shielding. Results: Effective dose from stray radiation was 396 mSv and 74 mSv for the existing and idealized nozzles, respectively, while modest modifications to the nozzle reduced effective dose emanating from the nozzle by 43%. Conclusion: These results add to the body of evidence supporting the suitability of passively‐scattered proton beams for the treatment of pediatric cancer and confirm that the effective dose from stray radiation was not excessive and can be substantially reduced by modest enhancements to the nozzle. Conflict of Interest (only if applicable): We would like to disclose that a similar presentation will be given to a largely different audience at the International Conference on Radiation Shielding in April 2008.
Glioblastoma accounts for the majority of adult malignant brain tumors, with an overall incidence... more Glioblastoma accounts for the majority of adult malignant brain tumors, with an overall incidence of 3.2 per 100,000 individuals. The median age at diagnosis is 64 years, and the incidence in patients aged ≥65 years is likely to increase due to an ageing population. 1,2 Despite standardof-care treatment (surgical resection, followed by radiotherapy and temozolomide [Stupp protocol]), the prognosis for elderly patients with glioblastoma remains poor. 2 Median survival for patients who receive treatment is 6 to 9 months 5-7 compared with <6 months for untreated patients, reflecting less favorable tumor biology, less aggressive treatment, and more comorbidities. Since receiving US Food and Drug Administration (FDA) approval in 2009 for the treatment of adults with recurrent glioblastoma, 9-11 bevacizumab (BEV) has been widely used for this indication in the US (in two US cohorts, 80% to 86% of patients with recurrent glioblastoma had received
To determine the influence of histopathological diagnosis on the outcome of &amp;amp;amp;amp;... more To determine the influence of histopathological diagnosis on the outcome of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;radioresistant&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; brain metastases treated with stereotactic radiosurgery (SRS). Patients (n = 189) with &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;radioresistant&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; brain metastases (n = 264) were consecutively treated with SRS between August 1991 and July 2002. The primary site of brain metastases was melanoma (n = 103), renal cell carcinoma (n = 77), and sarcoma (n = 9). The median age of the patients was 52 years, and the median Karnofsky Performance Scale score was 80. Initial brain metastasis presentation was single in 112 patients (59%). The median SRS dose was 18 Gy (range, 10-24 Gy). The median tumor volume was 1.6 cm3 (range, 0.06-27.5 cm3). The median follow-up of all patients was 7.4 months (range, 0.16-52 mo). The actuarial freedom from progression after 1 year was 64% for renal cell carcinoma patients, 47% for melanoma patients, and 0% for sarcoma patients (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). The median survival time for all patients from time of SRS was 7.5 months. The rate of 1-year survival was 40% for renal cell carcinoma patients, 25% for melanoma patients, and 22% for sarcoma patients (P = 0.0354). The incidence of neurological death was lower among patients diagnosed with renal cell carcinoma (31%) than among patients with melanoma (66%) or sarcoma…
Stereotactic and image guided surgery is becoming increasingly important in the management of bra... more Stereotactic and image guided surgery is becoming increasingly important in the management of brain tumors. Although there are several stereotactic modalities that have been reported to be of value, it is the combination of techniques in a multimodality approach that seems to show the most promise. Both frame-based and frameless guidance may facilitate glioma resection, allowing the optimal amount of resection while permitting avoidance of surrounding eloquent areas. Not only does this optimize resection, but leaving a minimal amount of gross tumor may provide a better bed for intracavitary chemotherapy. Deep tumors may be localized and approached through a small channel. Surgical exposure may be minimized to protect uninvolved areas of the brain. There is increasing evidence that patients operated with imaging guidance have a more benign course and more rapid discharge, perhaps with a lower incidence of adverse neurological sequelae. Stereotactic conformal radiotherapy allows a hig...
ABSTRACT Purpose: The “OneDose” MOSFET dosimeter, manufactured by Sicel Technologies, is used for... more ABSTRACT Purpose: The “OneDose” MOSFET dosimeter, manufactured by Sicel Technologies, is used for individualized patient dosimetry measurements for radiation therapy. These dosimeters, which are pre‐calibrated by the manufacturer, are designed for single use for conventional radiation therapy treatments. We tested the usefulness, reliability and applicability of these dosimeters for use in total body irradiation procedures, where the field sizes, distances, and irradiation conditions differ substantially from the standard conditions used for factory calibration Method and Materials: We have compared the response of OneDose dosimeters with that of Thermoluminescent Dosimeters (TLDs) calibrated “in‐house”. OneDose dosimeters were paired with two TLDs and were placed beneath bolus to provide adequate build‐up. The detectors with build‐up were then taped to the skin of the patient at various sites of interest, including the head, neck, umbilicus and lungs. In most cases, cerrobend lung blocks were used. Readings of the OneDose were taken immediately following irradiation. The TLDs were read 2 – 4 days later. Results: Of the four patients studied thus far, the doses measured at the head, neck, and umbilicus fell between 105 and 210 cGy. For these sites agreement with the TLDs was generally within ±5%. Measured doses for the regions of the lung showed greater variability. This may be due to placement errors or the lower doses (&lt; 20 cGy) and steeper dose gradients that occurred when the lungs were shielded with cerrobend blocks. Conclusion: The dose measured by the OneDose detector shows relatively good agreement with that measured by TLDs in total body irradiation. Our research plan includes study of another six patients, with the intent of being more precise in the placement of the dosimeters in the region of the lung. Conflict of Interest Information: ASB has a sponsored research agreement with Sicel Technologies, Inc. for the study of implantable sensors.
secutive individuals diagnosed with high grade glioma (diffuse astrocytoma IDH-wild type n=2, ana... more secutive individuals diagnosed with high grade glioma (diffuse astrocytoma IDH-wild type n=2, anaplastic astrocytoma n=18, and glioblastoma n=28) between June 2017 and October 2018. Patients who underwent subtotal (n=30, 62.5%), partial (n=17, 35.4%) removal or biopsy (n=1, 2.1%) were included in this analysis for interpreting radio-sensitivity of residual tumor. We investigated mATM by NGS of FFPE specimens with a TruSight Tumor 170 (TST-170) cancer panel. RESULTS: Among 48 samples, mATM was detected in 17% of cases (n=8). There was no significant difference in patient or tumor characteristics. Among mATM patients, there were 5 patients with glioblastoma and 3 patients with anaplastic astrocytoma IDH-wildtype. Most mutation was missense mutation (n=7, 88%). Median variant allele frequency was 44.7% (Interquartile range, IQR, 10.5-59.9%). Median follow-up duration after radiotherapy was 11.4 (IQR, 8.0-15.8) months. Radiation-related change was observed in 34 patients (71%). Tumors with mATM were related to higher frequency of radiation-related change at 6 months than tumors without mATM, respectively (88% and 64%, p = 0.016). Cases with mATM exhibited significantly 1-year progression free survival (PFS, 100% vs. 54%, p = 0.036). On subgroup of IDH WT (n=39) known as poor prognostic molecular marker, patients with mATM showed significantly higher PFS than patients without mATM (p=0.016, 1yr PFS 100% vs 43%). On subgroup with subventricular zone involvement (n=38) representative of aggressiveness, PFS of patients with mATM was significantly higher than others (p=0.026, 1yr PFS 100% vs 43.9%). CONCLUSIONS: Our results demonstrated that mATM is involved in radio-sensitivity with immediate radiologic change after radiation therapy followed by favorable radiologic response and clinical outcome beyond the aggressive nature of high grade glioma.
The optimal timing of adjuvant chemoradiation after surgical resection of glioblastoma remains un... more The optimal timing of adjuvant chemoradiation after surgical resection of glioblastoma remains unknown. The National Cancer Database was queried for all patients diagnosed with glioblastoma from 2004 to 2012 who underwent surgical resection followed by adjuvant chemoradiation. Cox proportional hazards modeling was used to determine factors influencing survival. Optimal thresholds for time to initiation (TTI) of adjuvant therapy were determined using recursive partitioning analysis (RPA). A total of 16,335 patients were included. The RPA model identified an optimal threshold of 61 days to initiation of adjuvant therapy which was confirmed with randomly selected training and validation sets using conditional inference trees repeated 1000 times for robustness. Compared to patients who initiated adjuvant therapy within 61 days (median overall survival: 14.1 months, 95% CI 13.8-14.3 months), patients who initiated adjuvant therapy after day 61 (MOS: 12.0, CI: 10.7-12.9) had higher risk of death (p < 0.0001). For patients with glioblastoma, large increases in time to the initiation of adjuvant therapy leads to inferior survival with a threshold of 61 days or less following surgical resection.
International Journal of Radiation Oncology Biology Physics, Feb 1, 2001
Methods and Materials: From April 1998 to December 1999, 40 postprostatectomy patients were treat... more Methods and Materials: From April 1998 to December 1999, 40 postprostatectomy patients were treated with intensity modulated radiation therapy (IMRT) to a median prescribed dose of 64 Gy (mean dose of 69 Gy). The Radiation Therapy Oncology Group (RTOG) scoring ...
Intraoperative magnetic resonance imaging (iMRI) is a useful adjunct for resection of primary mal... more Intraoperative magnetic resonance imaging (iMRI) is a useful adjunct for resection of primary malignant brain tumors (MBTs). The aim of our study is to investigate the impact of iMRI on health care utilization in patients who underwent craniotomy for resection of MBTs. MarketScan database were queried using the ICD-9/10 and CPT 4th edition, from 2008 to 2020. We included patients ≥ 18 years of age who underwent a craniotomy with at-least one year follow-up. Outcomes were length of stay (LOS), discharge disposition, hospital/emergency room (ER) re-admissions, outpatient services, medication re lls and corresponding payments. Of 6,640 patients who underwent craniotomy for MBTs, 465 patients (7%) had iMRI used during the procedure with 0.7% per year increase in iMRI use during the study period. Patients without iMRI use had higher complications at index hospitalization compared to those with iMRI use (19% vs 14%, p = 0.04). There was no difference in the ER admission rates among the patients who underwent surgery with and without iMRI use at 6-months and 1-year after the index procedure. In terms of post-discharge payments, no signi cant differences were noted among the patients without and with iMRI use at 6-months
NEURO-ONCOLOGY • NOVEMBER 2018 received prior chemotherapy before salvage surgery and RT. Overall... more NEURO-ONCOLOGY • NOVEMBER 2018 received prior chemotherapy before salvage surgery and RT. Overall, the 10-year PFS and OS were 52% and 65%, respectively. On multivariable analysis, lower KPS (HR:0.96, 95% CI:0.93-0.99), gliomatosis (HR:195, 95% CI:16-2340), and prior chemotherapy (HR:2.2, 95% CI:1.04-4.7) were the only significant factors associated with worse PFS; notably, age, grade, and EOR were not significant for PFS. In a subset of 146 patients excluding those with gliomatosis and prior chemotherapy, age >40, grade 3, subtotal resection, TMZ chemotherapy, and lower RT dose were not associated with worse PFS or OS rates (all p >0.05). CONCLUSIONS: Oligodendrogliomas with 1p/19q codeletion have favorable outcomes after RT, except those with gliomatosis or prior chemotherapy exposure. Traditional prognostic factors of age >40, EOR, and grade do not appear to reliably risk stratify these patients after adjuvant RT. Their use to guide treatment selection may need to be revisited.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2009
comparing both the measured dose profile and the isodose lines with those calculated by the Eclip... more comparing both the measured dose profile and the isodose lines with those calculated by the Eclipse TPS. It is possible to test the consistency of the delivered dose from spots with 58 different energies in one exposure by using the step phantom with MatriXX. Conclusions: The 2-D ion chamber array was found to be useful for quick real time QA checks of both the spot positioning accuracy and the consistency of dose delivery by multiple spots with different energies from a spot scanning proton therapy machine. All or some of the procedures explored in this study can become part of a periodic QA program for these machines.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2015
Results: Thirty-two patients (27%) quit smoking after SBRT, and 87 patients (73%) continued smoki... more Results: Thirty-two patients (27%) quit smoking after SBRT, and 87 patients (73%) continued smoking. Median follow-up was 22 months (range 2-87 months). Patients being treated for their first malignancy were twice as likely to quit smoking after SBRT as those with a prior malignancy, 35% vs. 18% (p Z 0.038). On univariate analysis, smoking status after treatment, age-adjusted Charlson comorbidity score, tumor size, and squamous histology were predictive of worse OS. The prior number of cigarette packyears was not significant in this population of patients still smoking at the time of treatment (p Z 0.62). On multivariate analysis, smoking status (HR 2.1, p Z 0.045), age-adjusted Charlson comorbidity score, and tumor size remained significant predictors of worse OS. In a Kaplan-Meier comparison, smoking cessation after SBRT was associated with an increase in 2-year OS, 78% vs. 69% (p Z 0.014). There was no difference in progression free survival (p Z 0.23) and local control (p Z 0.63) between the two groups. Conclusion: Overall survival is significantly improved in patients who can stop smoking after SBRT for early stage NSCLC, no matter their previous smoking history. Given this overall survival benefit, encouraging smoking cessation should be an important part of every post-treatment visit.
ABSTRACT Purpose: Proton therapy is an emerging treatment modality for pediatric cancer patients ... more ABSTRACT Purpose: Proton therapy is an emerging treatment modality for pediatric cancer patients because of its advantageous depth‐dose relationship. Although proton dose distributions conform to the target volume, stray neutrons deliver low doses to healthy tissues throughout the body. These exposures may increase the risk of radiation carcinogenesis, particularly for pediatric patients. The aim of this study was to quantify stray radiation dose for a pediatric patient receiving proton craniospinal irradiation and to evaluate methods of reducing stray radiation dose to the patient. Method and Materials: Equivalent dose to each organ and effective dose from stray radiation was estimated for a 30.6 Gy craniospinal treatment using Monte Carlo simulations of a passively‐scattered proton nozzle and a human phantom. The treatment plan and phantom were based on CT images of a 10‐year‐old boy treated for medulloblastoma. Comparisons were made between the existing nozzle, an idealized nozzle with no stray radiation, and the existing nozzle with modest modifications to suppress stray radiation. The existing nozzle was modified by increasing the distance from the patient to the primary external neutron source and enhancing the local shielding. Results: Effective dose from stray radiation was 396 mSv and 74 mSv for the existing and idealized nozzles, respectively, while modest modifications to the nozzle reduced effective dose emanating from the nozzle by 43%. Conclusion: These results add to the body of evidence supporting the suitability of passively‐scattered proton beams for the treatment of pediatric cancer and confirm that the effective dose from stray radiation was not excessive and can be substantially reduced by modest enhancements to the nozzle. Conflict of Interest (only if applicable): We would like to disclose that a similar presentation will be given to a largely different audience at the International Conference on Radiation Shielding in April 2008.
Glioblastoma accounts for the majority of adult malignant brain tumors, with an overall incidence... more Glioblastoma accounts for the majority of adult malignant brain tumors, with an overall incidence of 3.2 per 100,000 individuals. The median age at diagnosis is 64 years, and the incidence in patients aged ≥65 years is likely to increase due to an ageing population. 1,2 Despite standardof-care treatment (surgical resection, followed by radiotherapy and temozolomide [Stupp protocol]), the prognosis for elderly patients with glioblastoma remains poor. 2 Median survival for patients who receive treatment is 6 to 9 months 5-7 compared with <6 months for untreated patients, reflecting less favorable tumor biology, less aggressive treatment, and more comorbidities. Since receiving US Food and Drug Administration (FDA) approval in 2009 for the treatment of adults with recurrent glioblastoma, 9-11 bevacizumab (BEV) has been widely used for this indication in the US (in two US cohorts, 80% to 86% of patients with recurrent glioblastoma had received
To determine the influence of histopathological diagnosis on the outcome of &amp;amp;amp;amp;... more To determine the influence of histopathological diagnosis on the outcome of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;radioresistant&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; brain metastases treated with stereotactic radiosurgery (SRS). Patients (n = 189) with &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;radioresistant&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; brain metastases (n = 264) were consecutively treated with SRS between August 1991 and July 2002. The primary site of brain metastases was melanoma (n = 103), renal cell carcinoma (n = 77), and sarcoma (n = 9). The median age of the patients was 52 years, and the median Karnofsky Performance Scale score was 80. Initial brain metastasis presentation was single in 112 patients (59%). The median SRS dose was 18 Gy (range, 10-24 Gy). The median tumor volume was 1.6 cm3 (range, 0.06-27.5 cm3). The median follow-up of all patients was 7.4 months (range, 0.16-52 mo). The actuarial freedom from progression after 1 year was 64% for renal cell carcinoma patients, 47% for melanoma patients, and 0% for sarcoma patients (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). The median survival time for all patients from time of SRS was 7.5 months. The rate of 1-year survival was 40% for renal cell carcinoma patients, 25% for melanoma patients, and 22% for sarcoma patients (P = 0.0354). The incidence of neurological death was lower among patients diagnosed with renal cell carcinoma (31%) than among patients with melanoma (66%) or sarcoma…
Stereotactic and image guided surgery is becoming increasingly important in the management of bra... more Stereotactic and image guided surgery is becoming increasingly important in the management of brain tumors. Although there are several stereotactic modalities that have been reported to be of value, it is the combination of techniques in a multimodality approach that seems to show the most promise. Both frame-based and frameless guidance may facilitate glioma resection, allowing the optimal amount of resection while permitting avoidance of surrounding eloquent areas. Not only does this optimize resection, but leaving a minimal amount of gross tumor may provide a better bed for intracavitary chemotherapy. Deep tumors may be localized and approached through a small channel. Surgical exposure may be minimized to protect uninvolved areas of the brain. There is increasing evidence that patients operated with imaging guidance have a more benign course and more rapid discharge, perhaps with a lower incidence of adverse neurological sequelae. Stereotactic conformal radiotherapy allows a hig...
ABSTRACT Purpose: The “OneDose” MOSFET dosimeter, manufactured by Sicel Technologies, is used for... more ABSTRACT Purpose: The “OneDose” MOSFET dosimeter, manufactured by Sicel Technologies, is used for individualized patient dosimetry measurements for radiation therapy. These dosimeters, which are pre‐calibrated by the manufacturer, are designed for single use for conventional radiation therapy treatments. We tested the usefulness, reliability and applicability of these dosimeters for use in total body irradiation procedures, where the field sizes, distances, and irradiation conditions differ substantially from the standard conditions used for factory calibration Method and Materials: We have compared the response of OneDose dosimeters with that of Thermoluminescent Dosimeters (TLDs) calibrated “in‐house”. OneDose dosimeters were paired with two TLDs and were placed beneath bolus to provide adequate build‐up. The detectors with build‐up were then taped to the skin of the patient at various sites of interest, including the head, neck, umbilicus and lungs. In most cases, cerrobend lung blocks were used. Readings of the OneDose were taken immediately following irradiation. The TLDs were read 2 – 4 days later. Results: Of the four patients studied thus far, the doses measured at the head, neck, and umbilicus fell between 105 and 210 cGy. For these sites agreement with the TLDs was generally within ±5%. Measured doses for the regions of the lung showed greater variability. This may be due to placement errors or the lower doses (&lt; 20 cGy) and steeper dose gradients that occurred when the lungs were shielded with cerrobend blocks. Conclusion: The dose measured by the OneDose detector shows relatively good agreement with that measured by TLDs in total body irradiation. Our research plan includes study of another six patients, with the intent of being more precise in the placement of the dosimeters in the region of the lung. Conflict of Interest Information: ASB has a sponsored research agreement with Sicel Technologies, Inc. for the study of implantable sensors.
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