Biomedical subjects

J M Monihan

Publications and source records attributed to J M Monihan.

9 recordsLinked to original sources

PubMed1999

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.

Adult↗

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↗

PubMed1995

Expression of proliferating cell nuclear antigen in hyperplastic polyps, adenomas and inflammatory cloacogenic polyps of the large intestine.

AIMS: To compare proliferating cell nuclear antigen (PCNA) immunoexpression in hyperplastic polyps, adenomas, and inflammatory cloacogenic polyps of the human colon and rectum using paraffin wax embedded tissue. METHODS: The monoclonal antibody PC10 was used to demonstrate PCNA immunoreactivity in 88 polypoid lesions from 68 patients. Cases in which immunoexpression was completely absent were excluded, leaving 32 hyperplastic polyps, 31 adenomas, and seven inflammatory cloacogenic polyps for analysis. Labelling indices for the upper and lower third of each lesion and for adjacent normal mucosa were calculated. RESULTS: The upper third labelling indices for adenomas were substantially higher than those for hyperplastic polyps or normal mucosa, whereas those for the upper thirds of hyperplastic polyps and normal mucosa did not differ greatly. The differences between the lower third samples were not significant. In 16 (50%) hyperplastic polyps positive cells persisted onto the luminal surface. Some adenomas showed the most intense staining and the highest labelling indices in the upper third, with strong staining of surface cells; this pattern was not seen in the other lesions. The inflammatory cloacogenic polyps did not show a consistent pattern of immunoexpression. CONCLUSIONS: Differences in cell kinetics between adenomas, hyperplastic polyps, and normal mucosa may be shown in formalin fixed, paraffin wax embedded tissue using PC10 as a marker of proliferative activity. PCNA expression also persists into the upper portions of hyperplastic polyps. Assuming that hyperplastic polyps are hypermature lesions with a slower rate of cell migration, this finding suggests that there may be an alteration in PCNA protein metabolism.

Adenoma↗

PubMed1994

Squamous cell papillomas of the esophagus: a study of 23 lesions for human papillomavirus by in situ hybridization and the polymerase chain reaction.

This study assessed squamous cell papillomas of the human esophagus for the presence of human papillomavirus (HPV) and correlated the results with histological features. Twenty-three lesions obtained by endoscopic biopsy from 17 patients were studied, first by in situ hybridization (ISH) for HPV types 6-11, 16-18, 18, and 31-33-51, and second by the polymerase chain reaction (PCR) with amplification of multiple HPV types and demonstration of amplified product by ethidium bromide staining and Southern blot hybridization for HPV types 6-11, 16, and 18 in each case. Evidence of HPV DNA was found in only one lesion, which showed HPV type 6-11 by ISH and HPV positivity by Southern blotting of the amplified product after the PCR. This case exhibited histological features suggestive of HPV infection, although no morphological changes specific to the lesion were identified. The remaining 22 lesions, including those from cases in which multiple papillomas were present, were negative for HPV. The results show that HPV DNA is frequently not detectable in esophageal squamous cell papillomas, even when highly sensitive techniques are used. These findings are consistent with the hypothesis that other pathogenetic mechanisms, such as mucosal injury and repair, are important in the etiology of these lesions.

Adult↗

PubMed1994

CD34 immunoexpression in stromal tumours of the gastrointestinal tract and in mesenteric fibromatoses.

The aim of this study was to explore whether CD34 immunoreactivity can distinguish between different types of gastrointestinal stromal tumour, i.e. smooth muscle and neurogenic. We studied 87 stromal tumours from different sites in the gastrointestinal tract, as well as the omentum and mesentery, using a monoclonal antibody to CD34 (QBEND10). We also determined the immunoexpression of smooth muscle and muscle specific actins, S-100 protein, cytokeratin, desmin and vimentin. In addition, 15 cases of mesenteric fibromatosis were tested for CD34. Immunoexpression of CD34 was observed in 40 of the 87 stromal tumours and correlated with evidence of differentiation towards a smooth muscle phenotype. Large intestinal stromal tumours were less likely than gastric lesions to be CD34 positive. None of 15 cases of mesenteric fibromatosis was positive for CD34. We conclude that CD34 immunoexpression is seen in a proportion of stromal tumors of the gastrointestinal tract, mesentery and omentum, particularly those of smooth muscle type, and it may be useful as part of an immunohistochemical panel in the differential diagnosis of these neoplasms.

Antigens, CD↗

PubMed1994

Nonsteroidal anti-inflammatory drug-induced diaphragm disease arising in a bypassed ileal segment.

The formation of mucosal ileal diaphragms has been previously reported in patients receiving nonsteroidal anti-inflammatory drugs over extended periods of time. Whether this effect is the result of a local or systemic action by the medication has remained unknown. We report the first known instance of diaphragm disease arising in a segment of ileum that had been bypassed for many years and therefore was not exposed normally to luminal contact with the drug. This case supports at least a partial systemic mechanism in the production of the lesion.

Aged↗

PubMed1994

Squamous cell papilloma of the esophagus: a clinicopathologic and follow-up study of 25 cases.

OBJECTIVES: The aim of this study was to correlate clinical and pathologic features of squamous cell papillomas of the human esophagus and investigate their pathogenesis and malignant potential. METHODS: Clinical and pathologic data on 25 patients were studied. RESULTS: All patients in whom the race was known were white, and the majority of lesions occurred in the distal esophagus. There were multiple lesions in five cases. Many cases showed endoscopic evidence of hiatus hernia, gastroesophageal reflux, or esophagitis. No examples of Barrett esophagus were found. No esophageal malignancies occurred, and no dysplasia was seen histologically. Evidence of recurrence was found in only two patients, but several synchronous or metachronous carcinomas of the oro-respiratory tract occurred. CONCLUSIONS: Although our findings do not exclude a viral etiology, they suggest a role for mucosal injury and regeneration in the pathogenesis of these lesions. The association with other malignancies may be significant.

Adult↗

PubMed1989

Brunsting-Perry pemphigoid simulating basal cell carcinoma.

The cases of three patients whose initial clinical presentations suggested superficial multicentric basal cell carcinoma are reported. Although routine histologic examinations were nonspecific, direct immunofluorescence studies showed immunoglobin and/or complement deposition patterns diagnostic of Brunsting-Perry variant pemphigoid. There is a wide spectrum of clinical presentation of Brunsting-Perry pemphigoid. In cases in which there is a minimum of blistering activity, the use of direct immunofluorescence is invaluable for definitive diagnosis.

Aged↗

PubMed1986

Candida parapsilosis diagnosed by peripheral blood smear.

A 52-year-old man presented with a history of chronic lymphocytic leukemia and Kaposi's sarcoma. Three days after admission for clinical sepsis, yeast forms were noted within monocytes and neutrophils on a routine peripheral blood smear. Blood cultures yielded a pure culture of Candida parapsilosis. Despite antifungal therapy, the patient died 22 days after admission. This case represents the first reported instance of C parapsilosis sepsis diagnosed through a peripheral blood smear.

Candidiasis↗