Papers by Eduardo Zambrano
Games and Economic Behavior, 2005
I show that the predictive content of the hypothesis of subjective expected utility maximization ... more I show that the predictive content of the hypothesis of subjective expected utility maximization critically depends on what the analyst knows about the details of the problem a particular decision maker faces. When the analyst does not know anything about the agent´s payo s or beliefs and can only observe the sequence of actions taken by the decision maker any arbitrary sequence of actions can be implemented as the choice of an agent that solves some intertemporal utility maximization problem under uncertainty. for their comments to an earlier version of this work, and especially the associate editor and the referees for making suggestions that substantially improved the quality of the paper. I also received useful comments from the participants at a Cornell seminar. All remaining shortcomings are mine.
Head and Neck Pathology, 2010
NUT midline carcinomas (NMC) are a rare, recently described class of poorly-differentiated tumors... more NUT midline carcinomas (NMC) are a rare, recently described class of poorly-differentiated tumors that exhibit rapid onset and highly aggressive clinicopathologic behavior. These tumors are defined by rearrangement of the nuclear protein in testis (NUT) gene on chromosome 15q14, most commonly in a balanced translocation with the BRD4 gene on chromosome 19p13.1, resulting in the characteristic BRD4-NUT fusion gene and protein which blocks epithelial differentiation through chromatin binding. NMC frequently involve midline structures of adolescents and young adults and affect the head and neck region in 50% of cases. To our knowledge, only one case has been previously reported involving a salivary gland. Here, we present a case of a NMC of the salivary gland in an adolescent male presenting with an intermittently painful left submandibular mass of 3 months duration.
Endocrine Pathology, 2004
Introduction: Cowden’s disease (CD) and Bannayan-Ruvalcaba-Riley syndrome (BRRS) are allelic diso... more Introduction: Cowden’s disease (CD) and Bannayan-Ruvalcaba-Riley syndrome (BRRS) are allelic disorders characterized by multiple hamartomatous overgrowths of the thyroid, breast, skin, and gastrointestinal tract, and an increased risk of developing benign and malignant tumors of the breast and thyroid gland, secondary to germline point mutations in the PTEN gene. In contrast to thyroid epithelial lesions, abnormalities of the C-cells are currently not considered part of the spectrum of manifestations seen in PTEN-associated syndromes. Methods: The thyroid glands from two patients with overlapping CD/BRRS phenotypes, and with distinct PTEN mutations, were entirely submitted for histopathological examination, calcitonin immunostaining and C-cell mapping. Results: Multiple follicular adenomas and adenomatous nodules were present in the thyroid glands from both patients. A microscopic focus of papillary carcinoma was also present in one gland. C-cell hyperplasia was documented in both cases by calcitonin immunostaining. Conclusions: PTEN-associated tumor syndromes should be considered in the differential diagnosis of C-cell hyperplasia of the thyroid.
International Journal of Surgical Pathology, 2006
Sclerosing rhabdomyosarcoma, a particular phenotypic variant of rhabdomyosarcoma initially descri... more Sclerosing rhabdomyosarcoma, a particular phenotypic variant of rhabdomyosarcoma initially described in the adult population, has emerged as a potential pitfall in the evaluation of pediatric sarcomas. Because of its densely hyalinized collagenous matrix and its occasional expression of a pseudovascular pattern of growth, sclerosing rhabdomyosarcoma has been at times misdiagnosed as chondrosarcoma, osteosarcoma, or angiosarcoma. We describe 3 pediatric patients with sclerosing rhabdomyosarcoma and provide a detailed description of its distinguishing pathologic features. Awareness about this rhabdomyosarcoma variant and careful immunophenotypical evaluation are necessary to establish the correct diagnosis. Although no specific genetic aberrations have been recognized, yet the cytogenetic findings in 2 tumors of this series suggest a link with embryonal rhabdomyosarcoma. It is likely that further genotyping will result in better nosologic delineation of sclerosing rhabdomyosarcoma and that it will uncover pathogenetically and prognostically relevant genes.
Cancer Genetics and Cytogenetics, 2007
Aneurysmal bone cysts (ABC) are locally destructive bone lesions occurring predominantly in young... more Aneurysmal bone cysts (ABC) are locally destructive bone lesions occurring predominantly in young adults. There has been debate as to the neoplastic nature of these lesions. In recent years, however, compelling evidence of clonal chromosomal abnormalities has indicated a likely neoplastic origin. Although relatively few ABC have been assessed cytogenetically, many of those which have been studied have shown abnormalities of chromosome 17, particularly t(16;17)(q22;p13). We present a case of ABC in a 4-year-old female, which demonstrated the novel translocation t(X;9)(q26;q32).
American Journal of Surgical Pathology, 2004
Proliferative lesions of the bone surface, such as subungual (Dupuytren) exostosis and bizarre pa... more Proliferative lesions of the bone surface, such as subungual (Dupuytren) exostosis and bizarre parosteal osteochondromatous proliferation (BPOP, Nora lesion) are currently classified as reactive, proliferative processes that mimic primary neoplasms of bone. Cytogenetic analysis was performed on 3 subungual exostoses of the great toe and 2 BPOP lesions of the radius and ulna. A balanced translocation t(X;6) was identified in all cases of subungual exostoses. The chromosomal rearrangements observed in 1 case of BPOP differed from those seen in subungual exostosis. The presence of chromosomal abnormalities in subungual exostosis and BPOP suggests that these lesions are neoplastic, with a different molecular pathogenesis, and that each is a distinct clinicopathologic entity.
Cancer Genetics and Cytogenetics, 2007
Lipofibromatosis is a relatively rare pediatric neoplasm, which usually manifests as an ill-defin... more Lipofibromatosis is a relatively rare pediatric neoplasm, which usually manifests as an ill-defined soft tissue mass involving the upper and lower distal extremities, the trunk, and, less frequently, the head. To date, no cytogenetic abnormalities have been reported in this uncommon neoplasm. We present a case of lipofibromatosis featuring a three-way t(4;9;6) translocation in a 5-year-old boy.
International Journal of Surgical Pathology, 2006
All forms of cutaneous lymphomas are rare in children. Extranodal marginal zone B-cell lymphomas ... more All forms of cutaneous lymphomas are rare in children. Extranodal marginal zone B-cell lymphomas (EMZBL)/mucosa-associated lymphoid tissue (MALT) lymphomas are unusual neoplasms in children and young adults. We report a case of an EMZBL/MALT lymphoma of the lip in a previously healthy 14-year-old boy without immunodeficiency, confirmed by immunohistochemistry and documentation of clonal rearrangement of the immunoglobulin heavy-chain gene. Additionally, we present a review of the differential diagnosis of skin and mucosal lymphoid proliferations in childhood.
Pediatric and Developmental Pathology, 2002
Overproduction of catecholamines (dopamine [DA], norepinephrine [NE]) and their metabolites (homo... more Overproduction of catecholamines (dopamine [DA], norepinephrine [NE]) and their metabolites (homovanillic [HVA] and vanillylmandelic [VMA] acids) characterizes neuroblastoma (NB). In previous studies, increased urinary DA/NE, and DA/VMA ratios have been associated with poor prognosis, whereas low DA/NE ratios have been associated with longer disease-free survival. Higher urinary VMA, HVA, and NE levels have been found in association with low MYCN amplification, in contrast to cases with high MYCN amplification in which normal levels have been found. It is then believed that an “immature” catecholamine pattern indicates poor prognosis. We correlated urinary DA, NE, VMA, and HVA levels with age, clinical tumor stage, histological features (favorable [FH]/unfavorable [UH]) and MYCN status of 33 patients with NB. DA/VMA and DA/HVA ratios were also calculated. Wilcoxon rank sum and chi-squared tests were performed to determine statistical significance. Eighty-eight percent (15/17) of stage 3–4 cases had DA levels >2 times the upper limit of normal, but only 8% (1/12) of stage 1–2 cases had DA levels twice the upper limit of normal. In 61% (11/18) of stage 3–4 cases, the VMA level was >10 times the upper limit of normal, in contrast to stage 1–2 cases, in which only one patient (1/15) had a VMA level >10 times the upper limit of normal. Similar findings were obtained with urinary HVA and NE. Patients older than 12 months of age at diagnosis also had higher urinary levels of DA, VMA, HVA, and NE than those of patients younger than 12 months of age at diagnosis. Eighty-two percent (14/17) of stage 3–4 cases had DA/VMA ratios 12 months of age). In contrast, all stage 1–2 cases (12) had ratios MYCN-amplified cases had DA/VMA ratios MYCN-amplified case (1/3) had a ratio of 8.82; the other two MYCN-amplified cases had DA/VMA ratios of 0.09–0.11. Twenty-nine percent (2/7) of cases with UH had a DA/VMA ratio >1.4, but in all FH cases (14/14) the DA/VMA ratio was 12 months, stage 4, UH, and MYCN amplification). A seemingly novel observation in our study is that all high DA/HVA and DA/VMA ratios were obtained in stage 4 tumors, suggesting an association between the inability to metabolize DA and the acquisition of metastatic potential. On the basis of our results, we would like to emphasize the importance of determining not only DA, HVA, and VMA urinary levels, to support the diagnosis of NB, but also DA/HVA and DA/VMA ratios as a rapid initial assessment of prognosis in these patients.
Pediatric and Developmental Pathology, 2003
Renal cell carcinomas in children are extremely rare and are usually associated with specific chr... more Renal cell carcinomas in children are extremely rare and are usually associated with specific chromosomal rearrangements, different from those seen in adult patients. We present the case of a 9-year-old girl with a renal cell carcinoma with t(X;17) diagnosed at our institution. We also review the pertinent literature, with an emphasis on the genetic and molecular aspects associated with this rare neoplasm.
Pediatric and Developmental Pathology, 2004
Total parenteral nutrition (TPN)-induced liver injury is a common complication in neonates manage... more Total parenteral nutrition (TPN)-induced liver injury is a common complication in neonates managed with newborn intensive care. In several of these cases, irreversible and even fatal liver damage may develop, with patients dying of liver failure. In spite of multiple studies over several years, the pathogenesis of TPN-induced liver damage remains poorly understood. Clinical data from 24 neonates with clinical history of receiving TPN who died at Yale—New Haven Children’s Hospital and had autopsies performed, were collected by medical record review without knowledge of liver pathology findings. Liver histological sections from these patients were evaluated for multiple parameters without knowledge of the clinical course. Continuous data were analyzed by Wilcoxon signed-rank test and Mann-Whitney test, and dichotomous data by Fisher’s exact test; P n = 16), and the group with moderate-to-severe liver changes (n = 8). On the other hand, DTPN was significantly different between these two groups (P = 0.008). Also, patients small for gestational age (P = 0.003) and patients with bronchopulmonary dysplasia (P = 0.001) were more commonly seen in the group with moderate-to-severe histopathological findings. Intracellular copper was detected in 12.5% of patients with moderate-to-severe liver changes, and was found in 50% of patients with normal-to-mild liver findings (P = 0.04). Detection of copper from tissue sections also decreased with DTPN, being observed in 57% of patients with 12 wk DTPN. Our findings confirm the known significant relationship between the duration of TPN and liver injury. While previously described associations with birth weight, gestational age, enteral feedings, necrotizing enterocolitis, and sepsis were not noted, our study suggests that poor intrauterine growth may be a significant clinical risk factor for TPN-induced liver injury. In addition, our findings suggest that copper may have a protective effect against the development of TPN-induced liver damage.
Pediatric and Developmental Pathology, 2002
Overproduction of catecholamines (dopamine [DA], norepinephrine [NE]) and their metabolites (homo... more Overproduction of catecholamines (dopamine [DA], norepinephrine [NE]) and their metabolites (homovanillic [HVA] and vanillylmandelic [VMA] acids) characterizes neuroblastoma (NB). In previous studies, increased urinary DA/NE, and DA/VMA ratios have been associated with poor prognosis, whereas low DA/NE ratios have been associated with longer disease-free survival. Higher urinary VMA, HVA, and NE levels have been found in association with low MYCN amplification, in contrast to cases with high MYCN amplification in which normal levels have been found. It is then believed that an "immature" catecholamine pattern indicates poor prognosis. We correlated urinary DA, NE, VMA, and HVA levels with age, clinical tumor stage, histological features (favorable [FH]/unfavorable [UH]) and MYCN status of 33 patients with NB. DA/VMA and DA/HVA ratios were also calculated. Wilcoxon rank sum and chi-squared tests were performed to determine statistical significance. Eighty-eight percent (15/17) of stage 3-4 cases had DA levels Ͼ2 times the upper limit of normal, but only 8% (1/12) of stage 1-2 cases had DA levels twice the upper limit of normal. In 61% (11/18) of stage 3-4 cases, the VMA level was Ͼ10 times the upper limit of normal, in contrast to stage 1-2 cases, in which only one patient (1/15) had a VMA level Ͼ10 times the upper limit of normal. Similar findings were obtained with urinary HVA and NE. Patients older than 12 months of age at diagnosis also had higher urinary levels of DA, VMA, HVA, and NE than those of patients younger than 12 months of age at diagnosis. Eighty-two percent (14/17) of stage 3-4 cases had DA/VMA ratios Ͻ0.78, with the other 18% (3/17) showing ratios between 1.4 and 8.82 (all stage 4 and Ͼ12 months of age). In contrast, all stage 1-2 cases (12) had ratios Ͻ1.4. All (12/12) non-MYCNamplified cases had DA/VMA ratios Ͻ1.4 (0.06 -0.84), while one MYCN-amplified case (1/3) had a ratio of 8.82; the other two MYCN-amplified cases had DA/VMA ratios of 0.09 -0.11. Twenty-nine percent (2/7) of cases with UH had a DA/VMA ratio Ͼ1.4, but in all FH cases (14/14) the DA/VMA ratio was Ͻ1.4 (0.08 -0.084). Similar to previous studies, we found that aggressive NB is associated with higher urinary levels of DA, VMA, HVA, and NE. We also confirmed the previous observation that there appears to be a subset of NB in which a possible blockade in DA metabolism is associated with poor prognostic features (Ͼ12 months, stage 4, UH, and MYCN amplification). A seemingly novel observation in our study is that all high DA/HVA and DA/VMA ratios were obtained in stage 4 tumors, suggesting an association between the inability to metabolize DA and the acquisition of metastatic potential. On the basis of our results, we would like to emphasize the importance of determining not only DA, HVA, and VMA urinary levels, to support the diagnosis of NB, but also DA/HVA and DA/VMA ratios as a rapid initial assessment of prognosis in these patients.
Pediatric and Developmental Pathology, 2007
A 5-month-old girl with clinical features of Beckwith-Wiedemann syndrome (BWS), including a repai... more A 5-month-old girl with clinical features of Beckwith-Wiedemann syndrome (BWS), including a repaired omphalocele, an earlobe crease, enlarged adrenal glands, renal size discrepancy, and hyperinsulinemic hyperglycemia, presented with a 1.9-cm liver nodule. Markedly increased serum alpha-fetoprotein (AFP) levels (1,060,000 mg/L), highly suspicious for hepatoblastoma, were detected, and resection of the liver mass was performed. Histologic sections showed features characteristic of a mesenchymal hamartoma of the liver (MHL). No features of embryonal or fetal hepatocellular proliferation or heterologous stromal components were noted. By immunohistochemistry, the hepatocytes expressed AFP, but no nuclear accumulation of beta-catenin was present. Electron microscopy revealed normal, mature hepatocytes. Here we address the diagnostic challenge of the uncommon association of MHL and BWS in the setting of markedly elevated serum AFP levels. In addition, we analyze the unusual pancreatic lesion (focal endocrine adenomatosis) leading to severe hyperinsulinemic hypoglycemia in a patient with possible BWS. We emphasize that MHLs may present with markedly increased serum AFP levels, mimicking hepatoblastomas, and may also be part of the expanding spectrum of findings of BWS.
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Papers by Eduardo Zambrano