Elastosis and elastofibromatous change in the gastrointestinal tract: a clinicopathologic study of 13 cases and a review of the literature.

We describe 13 cases in which the submucosa and muscularis mucosae of the gastrointestinal tract exhibited a focal or diffuse increase of elastin fibers. This elastosis or elastofibromatous change most commonly manifested as a colonic polyp and usually was found during screening colonoscopy. Gastric and small intestinal cases were less frequent and associated with ulcers or an inflammatory process. The literature includes reports of 13 gastrointestinal elastotic lesions with a topographic distribution similar to that in our series. Histologically, elastosis appears as finely granular and/or fibrillar amphophilic material, sometimes with a fibrous component (elastofibromatous change). The changes occasionally appear centered around blood vessels and often are mistaken for amyloid but are negative for Congo red stain and strongly positive for elastin stain. We believe that this lesion might be more underrecognized than rare. In 2 of 26 cases, elastotic lesions also were present in nongastrointestinal sites.

Gastric glomus tumor.

Gastric glomus tumors are rare neoplasms that may present with upper gastrointestinal symptoms, or may be discovered incidentally. They may mimic other tumors both grossly and microscopically. They are usually benign and, although the exceptional case with aggressive behavior cannot be reliably predicted, large size may be of prognostic importance. We describe a 3.8 cm gastric glomus tumor in a patient who also had adenocarcinoma arising in an adenoma of the rectum, and discuss the differential diagnosis and prognosis.

From the archives of the AFIP. Meckel diverticulum: radiologic features with pathologic Correlation.

Meckel diverticulum is the most common congenital anomaly of the gastrointestinal tract, occurring in 2%-3% of the population. It results from improper closure and absorption of the omphalomesenteric duct. Meckel diverticulum is the most common end result of the spectrum of omphalomesenteric duct anomalies, which also include umbilicoileal fistula, umbilical sinus, umbilical cyst, and a fibrous cord connecting the ileum to the umbilicus. The formation of Meckel diverticulum occurs with equal frequency in both sexes, but symptoms from complications are more common in male patients. Sixty percent of patients come to medical attention before 10 years of age, with the remainder of cases manifesting in adolescence and adulthood. Heterotopic gastric and pancreatic mucosa are frequently found histologically within the diverticula of symptomatic patients. The most common complications are hemorrhage from peptic ulceration, small intestinal obstruction, and diverticulitis. Although the clinical, pathologic, and radiologic features of the complications of Meckel diverticulum are well known, the diagnosis of Meckel diverticulum is difficult to establish preoperatively.

Clinical and molecular biologic characteristics of early-onset versus late-onset colorectal carcinoma in Filipinos.

A case-control study of Filipino patients who underwent surgical resection for colorectal cancer (CRC) during a 1-year period was undertaken. Thirty-five patients under age 40 years were identified. Paraffin blocks of these and 35 randomly selected patients over age 40 underwent histologic and immunohistochemical evaluation. Markers chosen for evaluation included the apoptosis-associated gene products (p53 and bcl-2), a tumor proliferation activity-related factor (Ki-67), and the markers (MLH1 and MSH2) of DNA microsatellite instability (MSI). Results were correlated with age and the stage and location of the tumor. The average age of the early-onset group was 30.7 years compared to the late-onset group at 67.0 years; and the male/female ratio was equivalent. The younger patients had a significantly higher Dukes' stage, the tumors were more poorly differentiated, and they were more frequently of the mucinous and signet ring cell histopathologic type. Expression of p53 was higher in the younger patients ( p < 0.001) and was independent of the degree of differentiation or the stage of the tumor. No differences of expression were noted for the other markers measured. The increased frequency of CRC in Filipino patients less than 40 years of age offers a unique opportunity to gain a better understanding of carcinogenesis, which might be exploited during diagnosis and management. The differences noted between the early- and late-onset CRC are provocative and provide an impetus for increased screening in Filipinos.

Predictive value of diminutive colonic adenoma trial: the PREDICT trial.

BACKGROUND & AIMS: Diminutive adenomas (1-9 mm in diameter) are frequently found during colon cancer screening with flexible sigmoidoscopy (FS). This trial assessed the predictive value of these diminutive adenomas for advanced adenomas in the proximal colon. METHODS: In a multicenter, prospective cohort trial, we matched 200 patients with normal FS and 200 patients with diminutive adenomas on FS for age and gender. All patients underwent colonoscopy. The presence of advanced adenomas (adenoma >or= 10 mm in diameter, villous adenoma, adenoma with high grade dysplasia, and colon cancer) and adenomas (any size) was recorded. Before colonoscopy, patients completed questionnaires about risk factors for adenomas. RESULTS: The prevalence of advanced adenomas in the proximal colon was similar in patients with diminutive adenomas and patients with normal FS (6% vs. 5.5%, respectively) (relative risk, 1.1; 95% confidence interval [CI], 0.5-2.6). Diminutive adenomas on FS did not accurately predict advanced adenomas in the proximal colon: sensitivity, 52% (95% CI, 32%-72%); specificity, 50% (95% CI, 49%-51%); positive predictive value, 6% (95% CI, 4%-8%); and negative predictive value, 95% (95% CI, 92%-97%). Male gender (odds ratio, 1.63; 95% CI, 1.01-2.61) was associated with an increased risk of proximal colon adenomas. CONCLUSIONS: Diminutive adenomas on sigmoidoscopy may not accurately predict advanced adenomas in the proximal colon.

Carcinoid tumor of the esophagus: a clinicopathologic study of four cases.

Several case reports have emphasized that esophageal carcinoid tumors are associated with a poor prognosis. To expand our knowledge about the pathology and biologic behavior of these rare tumors, we reviewed the clinicopathologic and immunohistochemical findings of four cases of primary esophageal carcinoid. The age of the patients ranged from 48 to 82 years (mean 63 years; median 61 years). The lower segment of the esophagus was involved in two cases and the mid segment was involved in one case. The sizes of the tumors ranged from 0.3 cm to 3.5 cm. Two tumors were confined to the lamina propria and two invaded into the muscular wall. Two tumors appeared polypoid, whereas the remaining two were incidental findings and associated with adenocarcinoma arising in a background of Barrett esophagus. The adenocarcinoma was superficially invasive in one case, whereas it penetrated the muscular wall in the other. All four carcinoid tumors were immunoreactive with chromogranin and synaptophysin. There was focal expression of serotonin in two cases, glucagon in one case, and pancreatic polypeptide in one case. Endocrine cell hyperplasia was noted in both the Barrett esophagus and the invasive adenocarcinoma. One patient died secondary to postoperative pneumonia. Three patients are alive and disease free at 1, 6, and 23 years status post therapy. None of the patients had metastatic disease. These findings show that esophageal carcinoids are associated with a favorable prognosis. They arise in two settings: (1) a single large polypoid tumor or (2) an incidental finding and in association with adenocarcinoma arising in the background of Barrett esophagus. The presence of endocrine cell hyperplasia in the Barrett mucosa and the adenocarcinoma supports the hypothesis that these lesions arise from a common stem cell.