Robert E. Petras

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BACKGROUND & AIMS Treatment for invasive adenocarcinoma in colorectal polyps (malignant polyps) is controversial. The aim of this study was to evaluate our institutional treatment strategy for malignant polyps. METHODS Malignant polyps were designated as having favorable histology (grade I or II carcinoma with at least a 2-mm free margin) or unfavorable(More)
We correlated the histopathology with outcome for all patients with endoscopically removed colonic polyps containing invasive adenocarcinoma seen at our institution over a 10-yr period. Invasion was defined as infiltration of malignant cells into the submucosa. Of a total of 1523 adenomatous polyps, 41 polyps (2.7%) in 39 patients contained invasive(More)
The pathogenesis of Crohn's disease (CD), an idiopathic inflammatory bowel disease, is attributed, in part, to intestinal bacteria that may initiate and perpetuate mucosal inflammation in genetically susceptible individuals. Paneth cells (PC) are the major source of antimicrobial peptides in the small intestine, including human alpha-defensins HD5 and HD6.(More)
Solitary endobronchial papillomas in adults are rare neoplasms. Only sporadic cases have been documented. The histologic classification of these tumors remains problematic, and little is known about their clinical behavior. The clinical and pathologic features of 13 endobronchial papillomas and a single endobronchiolar papilloma were reviewed. In situ(More)
BACKGROUND Endoscopically applied methylene blue selectively stains specialized columnar epithelium in Barrett's esophagus. METHODS The diagnostic yield and cost of cancer surveillance in patients with Barrett's esophagus using methylene blue-directed biopsies (MBDB) were compared with surveillance using a "jumbo" random biopsy technique in a prospective,(More)
One hundred patients with familial adenomatous polyposis have prospectively undergone gastroduodenoscopy to identify and characterise polyps found. Forty six patients had polyps in the stomach or duodenum. Thirty five patients had adenomas (33 in duodenum, two in stomach) and 26 patients had fundic gland polyps. Some of these patients had polyps in the(More)
There are relatively few reports that detail the types of intestinal adenocarcinoma complicating Crohn's disease and examine associated epithelial dysplasia. We determined the prevalence, grade, and type of dysplasia found adjacent to and distant from Crohn's-related adenocarcinomas. Thirty cases of resected Crohn's-related adenocarcinoma were reviewed, and(More)
Leiomyosarcoma of the rectum and anal canal is rare and the optimal treatment is not clear. Eight patients with isolated anorectal leiomyosarcoma treated surgically were reviewed. The age ranged from 44 to 76 years (median 63 years) and the follow up ranged from 6 months to 4.5 years (median 2 years). All patients were symptomatic at presentation. All(More)
Idiopathic granulomatous gastritis (IGG) is a diagnosis made only by excluding other causes of granulomatous gastritis, such as infection, foreign bodies, and systemic granulomatous diseases. Recently, several investigators have questioned the existence of IGG. We reviewed the slides and clinical data of all cases of granulomatous gastritis seen at the(More)
N-acetyltransferase 1 (NAT1) and 2 (NAT2) are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD) consist of Crohn's disease (CD) and(More)