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L H Sobin

Publications and source records attributed to L H Sobin.

At least 19 recordsLinked to original sources
PubMed1997

Gastric "pseudolymphoma": a retrospective morphologic and immunophenotypic study of 97 cases.

BACKGROUND: The term "pseudolymphoma" has been used to describe lymphoid lesions that show: 1) borderline features between hyperplasia and neoplasia or 2) benign tumor-like enlargement of lymphoid tissue. The term pseudolymphoma has been applied to lesions in many anatomic locations, with the stomach being one of the more common sites. In spite of the frequent use of this term, neither the histologic criteria nor the clinical significance of this lesion have ever been clearly defined. Since the description of mucosa-associated lymphoid tissue (MALT) and its corresponding MALT-type lymphomas, the value of the term gastric pseudolymphoma has come into question. METHODS: The authors reviewed all cases diagnosed as gastric pseudolymphomas at the Armed Forces Institute of Pathology from 1970 to 1985. This period predated the description of low grade B-cell lymphoma of MALT-type. The cases were reclassified in light of current criteria and correlated with immunohistochemical findings and follow-up information. No patients were treated with chemotherapy or radiation therapy. RESULTS: Seventy-seven of 97 cases formerly diagnosed as pseudolymphoma were determined to be malignant lymphomas; the majority (51 cases) were extranodal marginal zone B-cell lymphomas (MALT-type). The remaining cases included reactive lymphoid hyperplasia associated with chronic follicular gastritis (15 cases) and atypical lymphoid infiltrates (5 cases). CONCLUSIONS: Most cases previously considered to be gastric pseudolymphomas are, by current criteria, malignant lymphomas. A small proportion are benign reactive lymphoid hyperplasias. Those cases of borderline or inconclusive nature are best diagnosed as atypical lymphoid infiltrates. The term gastric pseudolymphoma should be abandoned.

Adolescent↗
PubMed1997

Carcinoids of the jejunum and ileum: an immunohistochemical and clinicopathologic study of 167 cases.

BACKGROUND: Carcinoid tumors of the gastrointestinal tract differ in their clinical and histopathologic features, depending on the site of origin. There are few clinicopathologic studies that specifically describe jejunoileal carcinoid tumors. METHODS: One hundred sixty-seven ileal and jejunal carcinoids were retrospectively studied with emphasis on clinical, pathologic, immunohistochemical, and prognostic features. RESULTS: The mean age of patients at the time of presentation was 62 +/- 12 years (range, 13-93 years). Eight patients had carcinoid syndrome (5%) and 1 had Zollinger-Ellison syndrome. Twenty-six percent of tumors were multiple, and 77% were transmurally invasive; 31% had regional lymph node metastases only, and 32% had liver or mesenteric metastases. Ninety-three percent of tumors had an insular growth pattern. Serotonin was expressed in 86% of tumors (86 of 102), chromogranin in 92%, and neuron specific enolase in 95%. Twenty percent of tumors (10 of 51) expressed prostatic acid phosphatase; 96% were argyrophil, and 98% argentaffin. Of 80 cases with follow-up data (mean follow-up, 52 +/- 5 months), 21% were dead of disease, 16% were dead of other causes, 19% were alive with disease, and 44% had no evidence of disease at last follow-up. The 5-year Kaplan-Meier survival estimate for all cases was 58%. By univariate analysis, survival was negatively correlated with distant metastases at the time of surgery (P = 0.002), mitotic rate (P = 0.01), tumor multiplicity (P = 0.01), the presence of carcinoid syndrome (P = 0.02), depth of invasion (P = 0.03), and female gender (P = 0.05); by multivariate analysis, survival was negatively associated with distant metastasis (P = 0.002), carcinoid syndrome (P = 0.01), and female gender (P = 0.03). CONCLUSIONS: Jejunoileal carcinoid tumors have a relatively high rate of transmural invasion and aggressive clinical behavior. They are usually insular and largely argentaffin, with a high rate of chromogranin and serotonin positivity. These features differentiate jejunoileal carcinoids from other gastrointestinal carcinoids.

Adolescent↗
PubMed1997

Sclerosing mesenteritis, mesenteric panniculitis and mesenteric lipodystrophy: a single entity?

We reviewed 84 cases coded as mesenteric lipodystrophy (ML), mesenteric panniculitis (MP), or retractile mesenteritis and sclerosing mesenteritis (SM), grading fibrosis, inflammation, and fat necrosis, and evaluating clinical subgroups. There was no gender or racial predominance. Patient age range was 23-87 years (average 60). Patients most often presented with abdominal pain or a palpable mass. A history of trauma or surgery was present in four of 84 patients. The most common site of involvement was the small bowel mesentery as a single mass (58 of 84) with an average size of 10 cm, multiple masses (15 of 84), or diffuse mesenteric thickening (11 of 84). All patients had some degree of fibrosis, chronic inflammation, and fat necrosis. Although a few patients showed a sufficient prominence of fibrosis, inflammation, or fat necrosis to permit a separation into SM, MP, or ML, respectively, in most patients these three components were too mixed for a clear separation. The clinical, demographic, and gross features did not help in defining these three entities. Contributors diagnosed 12 as sarcoma. Of 39 patients followed beyond the postoperative period, none died of these lesions. We conclude that SM, MP, and ML appear to represent histologic variants of one clinical entity, and in most cases "sclerosing mesenteritis" is the most appropriate diagnostic term.

Adult↗
PubMed1996

Barrett esophagus with dysplasia. Flow cytometric DNA analysis of routine, paraffin-embedded mucosal biopsies.

Flow cytometric DNA ploidy analysis has been reported to be more objective and sensitive than morphologic evaluation as a surveillance method in patients with Barrett esophagus (BE) for the development and progression of precancerous lesions. Such analyses are typically performed using fresh samples that require a separate or "jumbo" biopsy, are prone to false DNA aneuploidy if not promptly processed, and do not allow for retrospective studies. The feasibility of performing flow cytometric DNA analysis on paraffin-embedded biopsies was studied to circumvent some of these problems using 12 squamous esophageal mucosa with inflammation and 58 BE cases showing varying degrees of dysplasia. Among the BE cases, 12 had no dysplasia, 20 were indefinite for dysplasia, 14 had low grade dysplasia, and 12 had high grade dysplasia. Satisfactory histograms were obtained in 86% of the analyzed samples. Among cases with adequate histograms, DNA aneuploidy was identified in 77% with high grade dysplasia, 16% with low grade dysplasia, 23% of indefinite for dysplasia, and 0% without dysplasia. One of the esophagitis samples was also DNA aneuploid. Correlation of DNA aneuploidy and degree of dysplasia is highly significant (P = .001). The authors have demonstrated that routinely processed paraffin-embedded biopsies can be used for flow cytometric ploidy analysis. DNA aneuploidy was highly correlated with degree of dysplasia and serves as a quantitative prognostic indicator for prospective as well as retrospective studies of the evolution of BE to carcinoma.

Barrett Esophagus↗
PubMed1996

Esophageal leiomyomatosis.

PURPOSE: To reassess the clinical and radiologic findings in patients with esophageal leiomyomatosis. MATERIALS AND METHODS: A search of the authors' radiologic archives revealed six cases of esophageal leiomyomatosis in a 22-year period. The clinical findings and radiologic images were reviewed retrospectively. RESULTS: The average age of the patients was 10.8 years (range, 6-18 years). Five patients presented with slowly progressive dysphagia. Barium studies revealed smooth, tapered narrowing of the distal esophagus in five patients and characteristic defects on the superomedial aspect of the gastric fundus abutting the cardia, presumably due to bulging of this thickened mass of muscle into the stomach, in four patients. In two patients, computed tomography (CT) revealed marked thickening of the distal esophageal wall. CONCLUSION: Esophageal leiomyomatosis can be suggested in a pediatric patient with long-standing dysphagia in whom smooth, tapered distal esophageal narrowing is seen at barium study and circumferential esophageal wall thickening is seen at CT.

Adolescent↗
PubMed1996

Small-cell carcinoma of the esophagus: radiographic findings.

PURPOSE: To determine the radiographic findings of small-cell carcinoma of the esophagus. MATERIALS AND METHODS: The authors retrospectively reviewed barium studies as well as medical and pathologic records for three cases of small-cell carcinoma of the esophagus contributed to the radiologic archives of the Armed Forces Institute of Pathology. RESULTS: Two patients presented with dysphagia and one with chest pain. In all three patients, barium studies revealed a smoothly marginated, sessile mass with a relatively flat central ulcer on the right postero-lateral wall of the midesophagus below the level of the carina. The masses all were 4-5 cm in diameter, and the ulcers were 2-3 cm in diameter. In all three patients, the results of endoscopy confirmed the presence of a sessile mass with central ulceration in the midesophagus. CONCLUSION: Small-cell carcinomas of the esophagus can have similar findings on barium studies. Although these findings are more likely to be caused by squamous-cell carcinoma, it is important to obtain endoscopic biopsy specimens, because preoperative histologic diagnosis of small-cell carcinoma can dramatically alter the management of these cases.

Aged↗
PubMed1996

Fibrovascular polyps of the esophagus: clinical, radiographic, and pathologic findings in 16 patients.

OBJECTIVE: Fibrovascular polyps of the esophagus are rare benign nonneoplastic intraluminal masses. Most published reports of patients with these polyps have been anecdotal. The purpose of this study was to reassess the clinical, radiographic, and pathologic findings in a relatively large series of patients with this unusual tumorlike lesion. MATERIALS AND METHODS: A search of the radiologic archives of the Armed Forces Institute of Pathology revealed 16 cases of fibrovascular polyps of the esophagus. We reviewed the clinical, radiographic, and pathologic findings in these 16 cases. RESULTS: All 16 patients were symptomatic. Fourteen (87%) had dysphagia and four (25%) had respiratory symptoms. The average duration of symptoms was 17 months, but seven patients (44%) had symptoms for 6 or fewer months. Two patients (12%) had a history of regurgitating the tumor into the pharynx or mouth, but none had the known complication of asphyxiation due to occlusion of the larynx. Chest radiographs revealed a right-sided superior mediastinal mass and/or anterior tracheal bowing in seven patients (44%). Barium studies revealed smooth but variably lobulated intraluminal masses that originated in the lower cervical esophagus and had variable sizes and distal extents, with an average length of 15 cm. Depending on the amount of fat and fibrovascular tissue in the lesion, CT revealed a heterogeneous appearance in four patients, lesions of predominantly fat density in two, and lesions of predominantly soft-tissue density in two. CONCLUSION: Knowledge of the clinical and radiographic features of fibrovascular polyps of the esophagus is important because surgical removal of these lesions is warranted in most patients.

Adult↗
PubMed1996

Leiomyosarcoma of the esophagus: radiographic findings in 10 patients.

OBJECTIVE: Leiomyosarcomas of the esophagus are rare malignant smooth-muscle tumors that have been described only anecdotally in the radiology literature. The objective of this study was to evaluate the clinical and radiographic findings of this unusual lesion. MATERIALS AND METHODS: A search of the radiology archives of the Armed Forces Institute of Pathology revealed 10 cases of esophageal leiomyosarcomas. Clinical and radiographic findings were reviewed retrospectively. RESULTS: All but one patient presented with dysphagia. The average duration of the dysphagia was 6.7 months, but five patients had dysphagia for 3 or fewer months. Frontal chest radiographs revealed a mediastinal mass in five patients. Barium studies revealed intramural lesions in six patients, intraluminal lesions in two, and infiltrative lesions in two. The intramural Lesions all had large exophytic components, and three contained ulceration or tracking. One of the intraluminal lesions appeared as a polypoid expansile mass and the other, as a smooth expansile sausage-shaped mass mimicking a fibrovascular polyp. CT revealed a mass involving the esophagus in five patients; three of these patients had heterogeneous lesions containing large exophytic components, central areas of low density, and extraluminal gas or contrast material within the tumor. In two patients, MR imaging revealed large masses that were isointense with skeletal muscle on T1-weighted images and hyperintense on T2-weighted images. CONCLUSION: Our experience suggests that esophageal leiomyosarcomas have radiographic findings similar to those of leiomyosarcomas elsewhere in the gastrointestinal tract. Esophageal leiomyosarcomas have a better prognosis than squamous cell carcinomas and are often amenable to surgical cure.

Adult↗
PubMed1996

Malignant melanomas in the small intestine: a study of 103 patients.

OBJECTIVES: Malignant melanoma shows an unusual predilection to metastasize to the small intestine. A proportion of small bowel melanomas occur without history of an antecedent primary. We evaluated a group of patients with malignant melanoma in the small intestine to further our understanding of this disease. METHODS: We reviewed 103 cases of malignant melanoma in the small intestine (77 surgical resections and 26 autopsies) accessioned at the Armed Forces Institute of Pathology between 1945 and 1991 for demographic, chronological, and pathological features. RESULTS: Mean age at time of primary was 45.6 yr for surgical and 34.1 yr for autopsy cases (p = 0.01). Mean age at time of small intestinal involvement was 52.2 yr for surgical and 42.7 yr for autopsies (p = 0.03). Primary lesions preceded intestinal disease by an average of 5.6 yr for surgical and 2.1 yr for autopsies. The age distribution of surgical patients with and without known primary melanomas at the time of small intestinal melanoma was not significantly different. The same was true for autopsy patients. Using regression analysis, the linear relationship of age at primary melanoma (AAP) on age at small intestinal melanoma (AASI) was given by AAP = 2.30 + 0.85 (AASI), and that of AASI on AAP was given by AASI = 3.94 + 1.02 (AAP) (r = 0.93 and p < 0.0001 for both regressions). CONCLUSIONS: Our data and results support the concept that small bowel involvement by melanoma, even without a known primary, is most probably metastatic. The age at which an unknown primary occurred in cases of intestinal melanoma, or the age at which intestinal metastasis may appear in cases with known primary melanoma, can be estimated. There appear to be two subsets of primary melanoma: one that occurs among younger patients and is more aggressive with rapid metastasis and early death and one that occurs among older patients, is more indolent, and metastasizes less rapidly.

Adult↗
PubMed1996

Unusual tumors of the appendix and pseudomyxoma peritonei.

This report covers hyperplastic and neoplastic lesions of the human vermiform appendix that, although unusual, are likely to be encountered by general surgical pathologists. Topics include epithelial neoplasms, hyperplastic polyps, diffuse epithelial hyperplasia, pseudomyxoma peritonei, goblet cell and tubular carcinoid tumors, neuroma, and neurogenous hyperplasia. We discuss recent advances in the prognosis and management of appendiceal carcinoma, current controversies regarding the relationship between ovarian and appendiceal epithelial neoplasms, the concept of the mucinous tumor of uncertain malignant potential (UMP), and practical aspects of reporting pseudomyxoma peritonei. Classical carcinoid tumors are beyond the scope of this article, and primary neoplasms that are so rare they occur in the literature only as isolated case reports are not covered.

Adenocarcinoma↗
PubMed1995

The World Health Organization's histologic classification of bone tumors. A commentary on the second edition.

BACKGROUND: The World Health Organization's histologic classification of bone tumors was revised in 1993. METHODS: The first edition was reviewed by an international panel of pathologists from nine countries and modified to incorporate advances made in the twenty years since it appeared. RESULTS: The framework and concept of the classification remain the same (i.e., based on histologic criteria in terms of differentiation shown by the tumor cells via conventional light microscopy supplemented by immunohistochemistry). New entities not described in the first edition include, for example, benign and malignant fibrous histiocytomas, well differentiated osteosarcoma, round-cell osteosarcoma, clear cell chondrosarcoma, primitive neuroectodermal tumor of bone, osteofibrous dysplasia, and giant cell reparative granuloma. CONCLUSION: The revised and expanded classification reflects advances in our knowledge, but is similar in concept and framework to the original version to allow comparisons between data collected in the past and future.

Humans↗
PubMed1995

Epithelial noncarcinoid tumors and tumor-like lesions of the appendix. A clinicopathologic study of 184 patients with a multivariate analysis of prognostic factors.

BACKGROUND: The current understanding of appendiceal epithelial tumors is based on series composed of relatively small numbers of patients and on case reports. The aim of this study was to perform clinicopathologic correlation, particularly concerning prognosis, on a relatively large series of patients with epithelial tumors and tumor-like lesions of the human vermiform appendix. METHODS: One hundred eighty-four cases of simple mucoceles, hyperplastic polyps, adenomas, carcinomas, and mucinous tumors of uncertain malignant potential (UMP) were reviewed. Retrospective follow-up data were obtained in carcinoma and UMP tumor cases. RESULTS: Most neoplasms were of the mucinous type characteristic of the appendix, but a small fraction were nonmucinous and resembled neoplasms typical of the spectrum encountered in the colorectum. Both benign and malignant conditions in some cases showed acellular mucin dissecting the appendiceal wall and mucin outside the appendix. Immunostains were sometimes helpful in identifying epithelial cells within mucus, but hematoxylin and eosin and mucin stains were adequate in most cases. Two factors were significantly associated with survival by multivariate analysis: the presence of mucin outside the right lower quadrant of the abdomen and the presence of epithelial cells in the peritoneal cavity outside the appendix. CONCLUSIONS: The distribution of mucin within the abdomen and the presence of cells outside the visceral peritoneum of the appendix are important prognostic factors that should be recorded in these neoplasms. Tumors designated as UMP lesions behave in a benign or low grade fashion.

Adenocarcinoma↗
PubMed1995

Cancer. Introduction.

This supplement presents the study of various histologic types of cancers diagnosed in the populations covered by the Surveillance, Epidemiology, and End Results (SEER) Program. It describes the SEER program and the coding of histologic type by the International Classification of Diseases for Oncology. Each of the 19 articles deals with the histologic types of cancer found in major sites or with specific histologic types, such as lymphomas or melanomas. Histologic types have been grouped based on those developed by Dr. John Berg. Data presented in this supplement are based on more than one million microscopically proven invasive cancers and 98,000 in situ cancers diagnosed during the period 1973-1987 in areas covered by the SEER Program.

Adolescent↗