Prognosis of gastrointestinal smooth-muscle (stromal) tumors: dependence on anatomic site

Although the significance of various prognostic factors, such as tumor size and mitotic index (MI), has been well established for smooth-muscle tumors of the stomach, the significance of these factors in other sites is less well defined. We studied 1004 patients with gastrointestinal smooth-muscle tumors for whom vital status could be determined. The average MI and tumor size varied significantly among the five major sites examined: esophagus (53 cases), stomach (524 cases), small bowel 252 cases), colon/rectum (108 cases), and omentum/mesentery/peritoneum (67 cases). There was a significant difference in site-specific survival (p = 0.001), with 10-year survival varying between 50% and 70%. Multivariate analysis demonstrated tumor location (p = 0.0320), size (p = 0.0003), MI (p < 0.0001), and patient age (p < 0.0001) to each carry independent prognostic value. The significance of MI was highly site dependent. Separation of survival curves for the stomach, using a threshold for analysis of either 5 or 10 mitotic figures/50 high-power fields, was very good. In contrast, small-bowel tumors showed little separation between survival curves, regardless of whether a threshold of 1, 5, or 10 mitotic figures MF/50 high-power fields was used to distinguish groups. In no site were tumor size and MI alone sufficient to provide an accurate long-term prediction of prognosis. Although tumor location, size, MI, and age have independent value in predicting the prognosis of patients with gastrointestinal smooth-muscle tumors, better methods are still required to accurately predict clinical course.

Gastrointestinal stromal tumors, intramural leiomyomas, and leiomyosarcomas in the rectum and anus: a clinicopathologic, immunohistochemical, and molecular genetic study of 144 cases

Gastrointestinal stromal tumors (GISTs), the specific KIT-positive mesenchymal tumors of the gastrointestinal tract, have been sporadically reported in the rectum, but there are few clinicopathologic series. In this study we analyzed the clinicopathologic features of 133 anorectal GISTs, 3 intramural leiomyomas (LMs), and 8 leiomyosarcomas (LMSs) from the files of the Armed Forces Institute of Pathology and the Haartman Institute of the University of Helsinki. Ninety-six GISTs were documented as KIT-positive and three additional ones as CD34-positive. Thirty-four tumors were included by their histologic similarity to KIT- or CD34-positive cases. GIST-specific c-kit gene mutations, mostly in exon 11, were documented in 18 of 29 cases (62%). The GISTs occurred in adults with the age range of 17-90 years (median 60 years) with a significant male predominance (71%). The tumors ranged from small asymptomatic intramural nodules to large masses that bulged into pelvis causing pain, rectal bleeding, or obstruction. They were mostly highly cellular spindle cell tumors; four tumors had an epithelioid morphology. The tumors coexpressed CD34 and KIT and were rarely positive for smooth muscle actin or desmin and never for S-100 protein. Seventy percent of patients with tumors >5 cm with more than 5 mitoses/50 high power fields (HPF) (n = 31) died of disease, whereas only one tumor <2 cm with <5 mitoses/50 HPF (n = 21) recurred and none caused death. Long latency was common between primary operation and recurrences and metastases; either one occurred in 60 of 111 patients with follow-up (54%). Distant metastases were in the liver, bones, and lungs. Three benign actin- and desmin-positive and KIT-negative intramural LMs, similar to those seen in the esophagus, were identified. There were eight LMSs, six of which formed a polypoid intraluminal mass and were actin-positive and KIT-negative. Despite high mitotic counts, only one LMS patient died of disease. A great majority of rectal smooth muscle and stromal tumors are GISTs, which have a spectrum from minimal indolent tumors to overt sarcomas. Intramural LMs are exceptional, and true LMSs are rare, and similar to colonic ones, often present as intraluminal polypoid masses that appear to have a better prognosis than GISTs with similar mitotic rates.

Gastrointestinal stromal tumors/smooth muscle tumors (GISTs) primary in the omentum and mesentery: clinicopathologic and immunohistochemical study of 26 cases

Gastrointestinal stromal tumor or smooth muscle tumor (GIST) is the designation for a major subset of gastrointestinal mesenchymal tumors that histologically, immunohistochemically, and genetically differ from typical leiomyomas, leiomyosarcomas, and schwannomas. Because GISTs, like the interstitial cells of Cajal, the gastrointestinal pacemaker cells, express CD117 (c-kit protein), the origin of GISTs from the interstitial cells of Cajal has been recently proposed. Comparison of GISTs primary in the omentum and mesentery to GISTs primary in the tubular gastrointestinal tract is of particular diagnostic and histogenetic interest in view of the possible similarity of these tumors with the GIST group. In this study, we analyzed 14 omental and 12 mesenteric primary mesenchymal tumors representing smooth muscle tumors or GISTs. These tumors were phenotypically compared with gastric and small intestinal GISTs, leiomyomas of the esophagus, and leiomyosarcomas of the retroperitoneum. Most (13 of 14) omental and mesenteric (10 of 12) tumors showed histologic features similar to GISTs with elongated spindle cells or epithelioid cells with high cellularity; most of these tumors showed low mitotic activity. Omental and mesenteric GISTs were typically positive for CD117 and less consistently for CD34. They often showed alpha-smooth muscle actin reactivity but were virtually negative for desmin and S-100 protein. One omental and two mesenteric tumors showed features of leiomyosarcoma with ovoid, less elongated nuclei, cytoplasmic eosinophilia; all these tumors had significant mitotic activity. These tumors were positive for alpha-smooth muscle actin and two of them for desmin, but all were negative for CD34 and CD117, similar to retroperitoneal leiomyosarcomas. Tumor-related mortality occurred in the group of mesenteric GISTs, but not in the group of omental GISTs. In contrast, all three patients with a true leiomyosarcoma of the omentum or mesentery had documented liver metastases or died of tumor. In summary, we show that tumors phenotypically identical with GISTs occur as primary tumors in the omentum and mesentery. The occurrence of CD117-positive tumors outside the gastrointestinal tract militates against an origin of these tumors exclusively from the interstitial cells of Cajal.

The WHO histological classification of thyroid tumors: a commentary on the second edition

This article introduces the revised WHO classification of thyroid tumors, giving an account of the major changes made and the reasons behind the changes, as well as listing the actual classification now recommended. It is intended to draw general attention to the revision, the full version of which will be published separately.

Immunohistochemical spectrum of GISTs at different sites and their differential diagnosis with a reference to CD117 (KIT)

Gastrointestinal (GI) stromal tumor (GIST) is the designation for the major subset of GI mesenchymal tumors and encompasses most tumors previously classified as GI smooth muscle tumors. Although GISTs typically express CD117 (KIT), often express CD34, and sometimes express alpha-smooth muscle actin (SMA), the relative frequency of these markers has not been characterized in large series of GISTs of different sites, and the CD117 expression has not been fully characterized in intra-abdominal tumors. In this study, we immunohistochemically analyzed 292 GISTs throughout the GI tract, including omentum and mesentery, and compared the immunoreactivities with 211 other tumors that may enter in the differential diagnosis. GISTs were defined in this study as CD117-positive primary spindied or epithelioid mesenchymal tumors of the GI tract, omentum, or mesentery. The CD34 positivity of GISTs varied from 47% in small bowel to 96 to 100% in rectum and esophagus, whereas SMA expression showed the opposite patterns and was most frequent in the GISTs of small bowel (47%) and rarest in the GISTs of rectum and esophagus (10-13%). Desmin was seen only occasionally. S100 positivity was rare but was seen most frequently in small intestinal GISTs (15%). True leiomyomas from esophagus, muscularis mucosae of colorectum, and pericolic leiomyomas similar to uterine leiomyomas were negative for CD117 and CD34 and positive for SMA and desmin (46 of 46). Inflammatory fibroid polyps of stomach and small intestine were negative for CD117 but were often positive for CD34 (6 of 8) and variable for SMA (3 of 8). Inflammatory myofibroblastic tumors involving gastric or colonic wall were negative for CD117 but some showed CD117-positive endothelia. GI schwannomas were all negative for CD117 and positive for S100 protein (11 of 11). Extremely focal CD117 positivity was seen in the neoplastic cells of some retroperitoneal leiomyosarcomas and liposarcomas. Among other CD117-positive tumors were intestinal metastatic melanomas (8 of 11) and extraskeletal Ewing's sarcomas (5 of 11), two of which were abdominal. In conclusion, strong CD117 expression defines most primary GI mesenchymal tumors as GISTs, which show different patterns for CD34 and SMA in various parts of the GI tract. Some unrelated CD117-positive tumors (melanomas, Ewing's sarcomas) should not be confused with GISTs.

The morphology of cirrhosis. Recommendations on definition, nomenclature, and classification by a working group sponsored by the World Health Organization

This memorandum provides guidelines on the definition, nomenclature, and classification of cirrhosis, chronic hepatitis, and hepatic fibrosis. These are considered according to morphological characteristics and aetiology. It is hoped that this system will serve as a standard for diagnostic, research, and epidemiological purposes. The relationship of cirrhosis to liver cell carcinoma is briefly discussed and the possible morphological markers of an increased risk of malignancy are defined.

Precancerous conditions and epithelial dysplasia in the stomach

A distinction can be made between a precancerous condition and a precancerous lesion. The former is a clinical state associated with a significantly increased risk of cancer, whereas a precancerous lesion is a histopathological abnormality in which cancer is more likely to occur than in its apparently normal counterpart. Up to the present time atrophic gastritis, gastric ulcer, pernicious anaemia, gastric stumps, gastric polyps, and Ménétrier's disease have all been considered as precancerous conditions and lesions of the stomach. Of these, only atrophic gastritis, pernicious anaemia, gastric stumps, and certain types of gastric polyp can now be regarded as having any really significant malignant potential. The precancerous lesion common to these is epithelial dysplasia which can occur in ordinary (foveolar) gastric epithelium as well as in intestinal metaplasia. The criteria for grading dysplasia in gastric epithelium into mild, moderate, and severe grades are given, and attention is drawn to the problems of differentiating inflammatory or regenerative change from mild dysplasia and intramucosal carcinoma from severe dysplasia. The clinical and epidemiological implications of gastric dysplasia are discussed with suggestions for further research.

Esophageal stromal tumors: a clinicopathologic, immunohistochemical, and molecular genetic study of 17 cases and comparison with esophageal leiomyomas and leiomyosarcomas

Although rare elsewhere in the gastrointestinal tract, leiomyomas (LMs) are the most common esophageal mesenchymal neoplasms. In contrast, gastrointestinal stromal tumors (GISTs) predominate in the stomach and intestines but have not been documented in the esophagus. This study was undertaken to determine the clinicopathologic features and frequency of esophageal GISTs compared with LMs and leiomyosarcomas (LMSs) of the esophagus. A total of 68 stromal/smooth muscle tumors from the Armed Forces Institute of Pathology and the Haartman Institute of University of Helsinki were reclassified by current histologic and immunohistochemical criteria. There were 17 GISTs, 48 LMs, and three LMSs. The esophageal GISTs occurred in 12 men and five women with a median age of 63 years (range, 49-75 years). All tumors were from the lowest third of the esophagus, and the most common complaint was dysphagia, whereas two tumors were detected incidentally. Histologically the tumors had an overall basophilic appearance and showed combinations of solid, myxoid, and perivascular collarlike patterns with a spindle cell histology in 13 patients and epithelioid histology in four patients. All tumors were positive for CD117 and for CD34, whereas two patients were also positive for alpha-smooth muscle actin (SMA) and three patients were positive for desmin. One patient showed a unique immunophenotype with coexpression of CD117, CD34, SMA, and desmin. Nine patients died of disease, including all who had a tumor larger than 10 cm, and also one patient whose tumor showed five mitoses per 50 high-power fields. In comparison, esophageal LMs (n = 48) occurred in a younger population (median age, 35 years) but, similar to the GIST group, men predominated (67%). All LMs were clinically indolent tumors with no tumor-related mortality. The LMs showed eosinophilic cytoplasm, and were positive for desmin and SMA, and negative for CD117 and CD34. All three LMSs were large high-grade tumors that showed muscle cell markers but no CD117. All patients died of disease. Esophageal GISTs showed mutations in exon 11 of c-kit as described previously in gastric and intestinal GISTs. The separation of GISTs from esophageal LMs is important diagnostically because the former group has a high risk of malignant behavior.

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.

Gastrointestinal stromal tumors and leiomyosarcomas in the colon: a clinicopathologic, immunohistochemical, and molecular genetic study of 44 cases

Gastrointestinal stromal tumors (GISTs), mesenchymal tumors largely specific for the gastrointestinal tract, have been well defined in the stomach and small intestine, but have not been extensively documented or contrasted with true smooth muscle tumors in the colon. This study was undertaken to determine the clinicopathologic features of GISTs of the colon, excluding the rectum, and to compare them with leiomyosarcomas (LMSs) of the same location. A total of 37 colonic GISTs and seven LMSs from the files of the Armed Forces Institute of Pathology and the Haartman Institute of the University of Helsinki were analyzed. The GISTs occurred predominantly in adults older than 50 years of age (median, 67 yrs), and most were histologically malignant; four small benign tumors (< or = 1 cm) were incidentally detected, and 10 others had minimal mitotic activity (five or fewer mitoses per 50 high-power fields). The colonic GISTs were typically transmural tumors with frequent intraluminal and outward bulging components. Histologically, they usually showed a spindle cell pattern (92%), whereas 8% were epithelioid. Most tumors (19 of 25) were positive for CD117 (KIT) and for CD34 (16 of 27); six tumors coexpressed alpha-smooth muscle actin and CD117; none showed desmin or S-100 protein. C-kit mutations in exon 11 were seen in 5 (36%) of 14 colonic GISTs. None of the patients with incidental small tumors had a recurrence, whereas 2 of 10 patients with tumors larger than 1 cm but minimal mitotic activity died of the disease with liver metastasis. Nearly all patients whose tumor was larger than 1 cm and showed more than five mitoses per 50 high-power fields died of disease; half had evidence of metastasis. LMSs were typically intraluminally bulging, polypoid masses that showed a histologic likeness to differentiated smooth muscle cells. They occurred in five men and two women with a median age of 61 years. Most LMSs were high-grade histologically and showed smooth muscle actin, desmin, or both. All were negative for CD34 and CD117 and lacked c-kit mutations. Five of the seven patients died of disease, and two had a long-term survival, despite high mitotic activity. These results show that KIT-positive GISTs are more common than LMSs of the colon, and these tumor groups have clinicopathologic differences that warrant their separation.

The World Health Organization's Histological Classification of Salivary Gland Tumors. A commentary on the second edition

The second edition of the World Health Organization's Histological Classification of Salivary Gland Tumors is more extensive and detailed than the previous edition published 20 years ago. The new edition is based on data regarding newly described tumor entities and the behavior and prognosis of the previously classified tumors. The distinct morphologic features of monomorphic adenomas justify their separation for purposes of identification. Among the carcinomas, various types were distinguished for purposes of recognition, prognosis, and treatment. The term tumor was replaced by carcinoma in the following two entities: acinic cell carcinoma and mucoepidermoid carcinoma. The tumor-like lesions were described in more detail.

Gastrointestinal cancer

BACKGROUND

There are great differences in incidence and prognosis of cancer among the component sites of the digestive tract. Furthermore, a number of the histologic types of tumors at these sites differ in their incidence and prognosis.

METHODS

The SEER data from 1973 to 1987 on frequency, incidence, staging, and survival for the various histologic types of 194,452 cancers of the esophagus, stomach, and intestines were studied.

RESULTS

There was an increased incidence of adenocarcinomas of esophagus, gastric cardia, small intestine, and colon; incidence rates for rectal adenocarcinoma and esophageal squamous cell carcinoma remained stable; and rates for gastric adenocarcinoma decreased. Blacks had higher incidence rates than whites for gastric adenocarcinoma; squamous cell carcinoma of the esophagus; carcinoids of the small intestine, colon, and rectum; and gastric sarcomas. Whites, especially males, had higher incidence rates for adenocarcinomas of the esophagus and gastric cardia than did blacks. Blacks had lower rates for rectal adenocarcinomas than did whites, but slightly higher rates than whites for rectal mucinous carcinomas and colonic adenocarcinomas. Data on race, sex, survival, and time trends indicate that mucinous colorectal carcinomas are biologically different from other adenocarcinomas. Males had poorer overall survival than did females for most histologic types of digestive tract tumors. Appendiceal mucinous adenocarcinomas with distant metastases were associated with a high (50%) 5-year survival. The poor prognosis of cases diagnosed as colonic carcinoid raises the possibility that some of these actually may be carcinomas.

CONCLUSION

Studies of digestive tract cancer require analysis by histologic type for adequate assessment.

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.

The World Health Organization histological classification of tumours of the upper respiratory tract and ear. A commentary on the second edition

The second edition of Histological Typing of Tumours of the Upper Respiratory Tract and Ear, in the World Health Organization series International Histological Classification of Tumours, provides a comprehensive classification of tumors and tumor-like lesions occurring in (1) the nasal cavity and paranasal sinuses; (2) the nasopharynx; (3) the larynx, hypopharynx, and trachea; (4) the external ear; and (5) the middle and inner ear. The classification includes several newly recognized entities and many that were omitted from the first edition on account of their rarity. The terminology and definitions of several tumor types have been revised in the light of experience gained during the past 12 years. This article discusses the revised classification with special reference to some of the major changes in the listings, terminology, and definitions.

Mesenteric and omental cysts: histologic classification with imaging correlation

Forty-one cases of mesenteric and omental cysts are reported. Histologically, several specific types could be distinguished: lymphangioma, 19 cases; nonpancreatic pseudocyst, 11 cases; enteric duplication cyst, six cases; mesothelial cyst, three cases; and enteric cyst, two cases. A lymphangioma is usually a multiloculated cyst located in the mesentery that shows no discernible wall on computed tomography (CT) and may have characteristics of fat on CT and magnetic resonance imaging. Abnormalities in the small bowel mucosa were frequently noted on barium studies. A nonpancreatic pseudocyst is usually a unilocular or multilocular cyst located in either the mesentery or the omentum, with abundant debris sonographically and an enhancing wall on CT. An enteric duplication cyst is a unilocular cyst with an enhancing wall on CT. Mesothelial and enteric cysts are anechoic, thin-walled cysts. Emphasis is placed on the importance of identifying lymphangioma, which is more difficult to manage than the other forms of mesenteric and omental cysts.

Schwannomas in the colon and rectum: a clinicopathologic and immunohistochemical study of 20 cases

Schwannomas of the colon and rectum are uncommon and incompletely characterized tumors, and only a small number of cases have been reported. This study was undertaken to determine the clinicopathologic profile of such tumors. A total of 20 colorectal schwannomas were identified and analyzed in a review of 600 mesenchymal tumors of the colon and rectum from the files of the Armed Forces Institute of Pathology. The schwannomas occurred equally in men (n = 9) and women (n = 11) in a wide age range (18-87 years; median age 65 years). The most common location was cecum (n = 7), followed by sigmoid and rectosigmoid (n = 6), transverse colon (n = 3), descending colon (n = 2), and rectum (n = 1); the location of one tumor had not been specified. The tumors commonly presented as polypoid intraluminal lesions, often with mucosal ulceration. Rectal bleeding, colonic obstruction, and abdominal pain were the most common presenting symptoms. The most common histologic variant (n = 15) was a spindle cell schwannoma with a trabecular pattern and vague or no Verocay bodies. These tumors ranged from 0.5 to 5.5 cm in diameter. A lymphoid cuff with germinal centers typically surrounded these tumors and focal nuclear atypia was often present, but mitotic activity never exceeded 5 per 50 HPF. All four epithelioid schwannomas occurred in the descending colon or sigmoid, three of them as small submucosal tumors. There was one plexiform schwannoma in the sigmoid composed of multiple nodules of prominently palisading schwann cells similar to those seen in conventional soft tissue schwannomas. All tumors studied were strongly positive for S-100 protein and also for low affinity nerve growth factor receptor (p75), collagen IV, and GFAP. Three tumors had CD34-positive cells, but all were negative for CD117 (KIT), neurofilament proteins, smooth muscle actin, and desmin. The percentage of MIB-1-positive cells was usually less than 1% and never higher than 3%. Colorectal schwannomas behaved in a benign fashion with no evidence of aggressive behavior or connection with neurofibromatosis 1 or 2, based on follow-up information on 18 patients.

TNM classification of malignant tumors. A comparison between the new (1987) and the old editions

A major revision of the tumor, nodes, metastasis (TNM) classification has been published. It eliminates previous differences between the International Union Against Cancer (UICC) and American Joint Committee on Cancer (AJCC) versions. It also updates existing site classifications and adds chapters on previously unclassified tumors. This article summarizes the major changes from the past to the present editions of the TNM classification.

Body iron stores and risk of colonic neoplasia

BACKGROUND

Body iron stores and dietary iron intake have both been shown to be positively associated with subsequent risk of colon cancer. This finding comes from a cohort study involving 14,000 men, but the positive association occurred in only 12 cases.

PURPOSE

We performed a case-control study of 264 men and 98 women to test for an association between serum ferritin levels and the presence of adenoma of the colon that would be independent of other known risk factors.

METHODS

Serum ferritin levels were determined in this study from sera, frozen at -80 degrees C for 5-8 years, that had been originally obtained between 1984-1987 at the Walter Reed Army Medical Center from adult male and postmenopausal female patients undergoing routine colonoscopic examination and previously enrolled in a case-control study that assessed the potential dietary and environmental risk factors for colonic neoplasia. The presence of fecal occult blood in the stool or the suggestion of colonic polyps seen on barium enema defined eligibility for the study. Patients with known preexisting colonic disease were excluded. Eligible patients had their blood drawn and serum prepared. Following colonoscopy and histologic review, the patients were classified into three groups: normal (without neoplastic disease), 159 subjects; adenoma, 145 subjects; and colon cancer, 29 subjects. Body iron stores were determined by measuring serum ferritin levels by a competitive-binding radiometric immunoassay. Ferritin levels categorized into quintiles for adenoma were defined. Crude and adjusted odds ratios (ORadj) with 95% confidence intervals (CIs) for cancer and adenoma related to ferritin were calculated, controlling for known or suspected risk factors including sex, age, race, body mass index, family history, tobacco use, and alcohol consumption.

RESULTS

Statistically significant associations of adenoma risk were seen in the third ([ORadj] = 3.8; 95% CI = 1.5-9.5) and fourth (ORadj = 5.1; 95% CI = 2.0-12.7) quintiles of ferritin relative to the first quintile, for smoking history (ORadj = 2.4; 95% CI = 1.3-4.3), for male sex (ORadj = 1.9; 95% CI = 1.0-3.7), and for family history of polyps or cancer (ORadj = 1.8; 95% CI = 1.0-3.4). From a second set of analyses that excluded 36 patients with serum ferritin of greater than or equal to 399 ng/mL, the greatest effect of ferritin on adenoma risk by anatomic subsite was seen in the right colon.

CONCLUSION

The apparent dose-response for serum ferritin level and adenoma risk suggest that exposure to iron may be related to adenoma formation.

Goblet cell carcinoids and related tumors of the vermiform appendix

Appendiceal carcinoids with glandular differentiation pose difficulties in classification and prediction of clinical behavior. Sixty-four such cases were divided into three histologic groups on the basis of routine and immunohistochemical stains: (1) Tubular carcinoids were small and confined to the appendix, had small amounts of intraluminal mucin with few or no goblet cells, were nonargentaffin, lacked serotonin, and were diffusely positive for glucagon. All ten with follow-up (mean, 17 months) were without metastasis. (2) Goblet cell carcinoids were confined to the appendix and mesoappendix, circumferentially surrounded the appendiceal lumen, and were often not suspected grossly. Histologically, they were often mixed with small crypt-like glands and were serotonin positive. All 22 with follow-up (mean, 19 months) were without metastasis whether or not right hemicolectomy was performed. (3) Mixed carcinoid-adenocarcinomas showed spread into the cecum or adjacent viscera at the time of diagnosis and had a large carcinomatous pattern with areas of mucinous, signet-ring, or single-file structure, in addition to goblet cell or insular carcinoid. All patients had right hemicolectomies, and all but two with follow-up died of the disease (mean, 16 months). Although a histologic spectrum exists among carcinoid tumors and certain adenocarcinomas of the appendix, it is possible to delineate three biologically distinct groups. Surgical margins should be taken of all appendices because these tumors often do not form discrete masses.

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

The World Health Organization's (WHO) histologic classification of gastrointestinal tumors has been revised. Although the general basis of classification and the overall outline remain similar to the first edition, advances in the last decade justified changes in classifying certain entities; among them were malignant lymphomas, endocrine tumors, and dysplasias. Several newly recognized entities have also been added.

Association of mucinous tumors of the ovary and appendix. A clinicopathologic study of 25 cases

Twenty-five patients with mucinous tumors of the ovary and appendix were studied. The average age of the patients was 52 years, and the ovarian and appendiceal tumors were discovered synchronously in all but two cases. The majority had either a pelvic mass or abdominal or pelvic pain. A high frequency of bilateral ovarian tumors (11/25), and right-sided predominance for the unilateral ovarian tumors (nine right, five left) were found. Four patients had ovarian mucinous carcinomas, 10 had mucinous tumors of low malignant potential, 10 had mucinous cystadenomas, and one had a mucinous cyst. Pseudomyxoma ovarii was present in 22 cases. Twenty-two of 24 appendices were grossly abnormal. There were six appendiceal mucinous adenocarcinomas, 10 mucinous tumors of uncertain malignant potential, seven mucinous cystadenomas, one hyperplastic polyp, and one mucocele. Twelve patients had ovarian and appendiceal tumors of similar malignant potential, nine had appendiceal tumors with more aggressive morphologic features than the corresponding ovarian tumor, and four had ovarian tumors with more aggressive morphologic features than the appendiceal tumor. Eighteen patients had peritoneal involvement by mucinous epithelium admixed with mucus (nine localized, nine diffuse). Immunoperoxidase reactions for four epithelial antigens in 15 cases showed complete concordance between ovarian and appendiceal lesions in only five cases and were not helpful in determining the site of origin of the peritoneal tumor. Our findings suggest an independent origin of the ovarian and appendiceal tumors in most cases and do not favor an origin in a single site. Furthermore, it is proposed that the peritoneal lesions may arise de novo as part of a multifocal neoplastic process.

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.