1/12. Hyperplastic polyps: "more than meets the eye"? Report of sixteen cases.The vast majority of hyperplastic polyps are small, left-sided, and inconsequential in nature. However, hyperplastic polyps that are large, right-sided, mixed, and found in association with a family history of carcinoma may represent an "atypical" group, and their clinical significance is uncertain. We believe that these atypical lesions should not be lumped together with the common variety of diminutive hyperplastic polyps. Rather, when such hyperplastic polyps are encountered, they should be excised and the patient should be placed on regular colonoscopic surveillance.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/12. Ectopic prostatic tissue of the anal canal presenting with rectal bleeding: report of a case.PURPOSE: Ectopic prostatic tissue at various sites within and outside the genitourinary system has been reported previously. A case of ectopic prostatic tissue located in the anal canal causing rectal bleeding is presented. METHOD: The patient was referred to our clinic with rectal bleeding. At rectal examination a bleeding sessile polypoid mass 2.5 cm in size was found in anal canal and removed surgically. RESULTS: Histopathologic and immunohistochemical staining of the specimen confirmed the prostatic nature of the tissue. CONCLUSION: Prostatic heterotopia is significant in several respects. Either it may be an important cause of hematuria or unusually, as in our case, it may cause rectal bleeding. In addition, ectopic tissue may be endoscopically confused with malignancy in either urinary or lower gastrointestinal system. This and other reports may disclose the genesis and significance of this peculiar tissue remnant.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/12. Filiform polyposis: a case report describing clinical, morphological, and immunohistochemical findings.Filiform polyposis (FP) is a rare condition of uncertain pathogenesis, 28 cases of which have been published since it was first described in 1965. It is usually found in association with chronic inflammatory bowel disease, especially Crohn's disease and ulcerative colitis. The condition is characterized by the presence of numerous, densely packed, filiform polyps in the colon, which may resemble villous adenomas on endoscopy. We describe a case of FP occurring in a 33-year-old man with a 5-year history of Crohn's disease, in whom subtotal colectomy was performed because of perforation of the sigmoid colon. microscopy revealed inflammatory pseudopolyps covered by largely normal and non-dysplastic colonic epithelium. The neuroendocrine system of the intestine in FP was investigated for the first time in this case: marked hyperplasia of endocrine cells immunoreactive for serotonin, somatostatin and enteroglucagon and of neural structures immunoreactive for substance p and vasoactive intestinal peptide was noted in the polyps and the adjacent intestinal mucosa. The patient has experienced no further complications in the 12 months since the operation. Medication administered in FP depends mainly on the nature of the underlying disease, and the amount of information published about this condition is as yet insufficient to allow any one specific type of treatment to be recommended. FP alone is not an indication for bowel resection but complications, such as massive haemorrhage or intestinal obstruction, may necessitate surgical intervention.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/12. Localized lymphoid hyperplasia of the rectum resembling polypoid mucosa-associated lymphoid tissue lymphoma: a report of three cases.Histologically, benign lymphoid hyperplasia of the rectum is usually characterized by large lymphoid follicles with active germinal centers and by a narrow surrounding mantle zone and marginal zone (MZ). We report here three cases of benign lymphoid hyperplasia of the rectum associated with prominent marginal zone hyperplasia, which caused serious difficulty in the differential diagnosis from the polypoid type of mucosa-associated lymphoid tissue (MALT) lymphoma. colonoscopy demonstrated small sessile polyps in all three cases. Histologically, the lesions were characterized by a hyperplastic germinal center and expanded MZs. The expanded MZs contained numerous monocytoid B-cells (MBC) and scattered large transformed B-cells. Initially, combined colonoscopic and histological findings strongly supported a diagnosis of polypoid MALT-type lymphoma of the rectum. However, there were neither colonized lymphoid follicles nor lymphoepithelial lesions in any of the three lesions. MBCs and large transformed b-lymphocytes were CD43- and bcl-2-. Moreover, immunohistochemical and genotypic studies proved the polytypic nature of the b-lymphocytes in all three lesions. The present cases indicated that benign lymphoid hyperplasia of the rectum should be included in the differential diagnosis for polypoid MALT-type lymphoma of the rectum.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/12. Adenomatous polyp in a four-year-old child.A 4-year-old white boy presented with rectal bleeding. An isolated polyp was removed and on histology was found to be adenomatous in nature. family history was remarkable for polyposis with combined adenomatous and juvenile features. Variable expression of the syndrome was seen in various family members.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/12. Primary rectal lymphoma and malignant lymphomatous polyposis. Two cases illustrating current methods in diagnosis and management.Two cases of colorectal lymphoma are presented. Preoperative histologic diagnosis is difficult and examination of the fresh specimen using immunocytochemical and gene rearrangement techniques are necessary to establish the precise nature of the lesion. Surgical excision is the mainstay of treatment for localized lymphoma of the colorectum and chemotherapy for malignant lymphomatous polyposis.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/12. Malignant melanoma with metastasis to a colonic polyp.Tumor-to-tumor metastases are rare occurrences. A 75-yr-old male presented with an enlarging axillary mass. Further investigation revealed an adenocarcinoma of the colon and a colonic polyp. Metastatic malignant melanoma was present within the colonic polyp and in axillary lymph nodes. In the polypectomy specimen, the distinctly dimorphic histologic appearance was the best clue to the metastatic nature of the malignant component of the polyp. The diagnosis was confirmed by histochemistry and immunocytochemistry. This is the third reported instance of a colonic polyp acting as the host in a case of tumor-to-tumor metastasis.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/12. Pseudosarcomatous changes in inflammatory pseudopolyps of the colon.The occurrence of pseudomalignant changes in biopsy specimens from two patients with ulcerative colitis and pseudopolyposis is described. One lesion was characterized by the proliferation of large ganglion cell-like cells, similar to those observed in proliferative fasciitis. Ultrastructural and immunohistochemical findings supported a fibroblastic origin. biopsy specimens of an inflammatory pseudopolyp from the second patient showed proliferation of oval to spindle cells that were initially interpreted as a possible neoplasm. The site of origin and reactive nature of this lesion became apparent on a subsequent polypectomy specimen. attention is called to the occurrence of pseudosarcomatous changes in inflammatory pseudopolyps of the gastrointestinal tract that may lead to an erroneous diagnosis of malignancy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/12. Adrenal adenomas and adrenal carcinomas in association with hereditary adenomatosis of the colon and rectum.Hereditary adenomatosis of the colon and rectum (HACR) is associated with a wide variety of extracolonic manifestations. Two cases of neoplasia involving the adrenal gland are reported, one adenoma and one carcinoma. The literature relating these lesions to HACR and other syndromes of malignant and nonmalignant growth disturbance is reviewed. The increasing list of the extracolonic manifestations associated with HACR emphasizes the generalized nature of the growth disorder of this disease. An increased awareness of these lesions is important, as many patients with HACR now live longer by avoiding death from colorectal carcinomas due to the increasing usage of prophylactic colectomy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
10/12. Hamartomatous polyps in peutz-jeghers syndrome. A light-, histochemical, and electron-microscopic study.Multiple hamartomatous polyps from two patients with peutz-jeghers syndrome were studied using histochemical, electron-microscopic, and light-microscopic means. Using normal intestinal mucosa as control, mucosubstances containing sulfate, hexose and glycogen, as well as neutral and acid mucins, were detected. Electron-microscopic findings in different cellular populations of hamartomatous and normal mucosa were also evaluated. The results indicated the hamartomatous nature of such polypoid formations in peutz-jeghers syndrome. review of the literature supports the possibility of genetic predisposition of these patients to develop unusual types of neoplasms in unexpected localizations.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
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