Well-differentiated Papillary Mesothelioma Research Articles

Das maligne peritoneale Mesotheliom bei der Frau - Histologischer Subtyp und Differenzierungsgrad einer insgesamt seltenen Neoplasie bestimmen Krankheitsverlauf und Prognose -

Background: Malignant peritoneal mesothelioma is rare, particularly in women. Most mesotheliomas are aggressive but there are low-grade histologic subtypes. We describe two patients to illustrate the variable presentation and clinical course of this condition. Case Report: A 69-year-old patient with a history of asbestos exposure underwent surgery for a symptomatic and rapidly growing abdominal tumor. Postoperatively the tumor progressed and the patient died with progressive disease after 8 months. The second patient, a 26-year-old woman with no history of asbestos exposure, had miliary lesions discovered incidentally. The patient was and remains free of symptoms. Conclusion Most peritoneal mesotheliomas are aggressive lesions with an unfavorable prognosis. However, there are well-differentiated papillary mesotheliomas that fulfill the criteria of malignancy but are characterized by slow progression and a favorable prognosis without aggressive treatment.

Pathology of malignant mesothelioma

The diagnosis of malignant mesothelioma can pose several problems to the surgical pathologist. First, the morphological appearances of the tumour are known to be diverse with mimicry of a range of both reactive and neoplastic conditions. Second, due to the relative inaccessibility of the serosa, biopsy material is often scanty and fragmentary, producing a plethora of interpretive ambiguities. Third, adjunct techniques such as mucin histochemistry and immunohistochemistry, whilst useful in excluding malignant mesothelioma have little role in confirming the diagnosis. The accurate diagnosis of diffuse malignant mesothelioma is important for two reasons: (1) In relation to prognosis as it has an almost invariable fatal outcome, which contrasts with the other mesothelial neoplasms such as the benign adenomatoid tumour and the borderline malignant tumours, namely the well-differentiated papillary mesothelioma and multicystic mesothelioma; (2) In relation to occupational-related compensation claims following asbestos exposure. This review summarizes the aetiology of asbestos-induced neoplasia, possible mechanisms of tumour development and highlights potential diagnostic pitfalls.

Well-differentiated papillary mesothelioma of the peritoneum: A separate entity

Three female patients with a diffuse well-differentiated papillary mesothelioma of the peritoneum are presented. They did not have a history of exposure to asbestos. The peritoneal biopsies were studied extensively, including electron microscopy, nuclear morphometry and DNA ploidy analysis. The results from these more sophisticated investigations confirmed the mesothelial origin and further characterised these lesions. One of the 3 patients has continuing elevated serum CA-125 levels, which increased transiently during and after pregnancy. All 3 patients have done well without therapy, 2 patients being alive and non-symptomatic 6 and 7 years after the initial diagnosis. It is important to distinguish this disorder from the malignant diseases of the peritoneum and the ovary. In view of the indolent course of this subtype of mesothelioma, avoidance of treatment is justified unless there is evidence of progressive disease.

A Clinicopathologic Analysis of 11 Cases with Review of the Literature

Eleven malignant mesotheliomas of the testicular tunica vaginalis occurred in patients aged 12 to 76 (mean, 54.1) years. Hydrocele, with or without an associated mass, or appreciation of a paratesticular mass accounted for the clinical presentation. One patient had a history of asbestos exposure. Grossly, the tumors typically presented as multiple nodules studding a hydrocele sac, frequently associated with a mass infiltrating the spermatic cord or adjacent testis. Microscopically, five tumors were epithelial and six biphasic, with the typical architectural and cytologic features of mesothelioma. Mixtures of papillary, tubular, and solid patterns predominated in the epithelial areas; interlacing fascicles of spindle cells with scanty stroma characterized the sarcomatous components. All eight of the tumors that were stained for keratin (AE1/AE3) were positive, four of five for epithelial membrane antigen, and four of five for vimentin. Seven of seven tumors were carcinoembryonic antigen negative and five of five B72.3, Leu-M1, and Ber-Ep4 negative. Follow-up ranging from 1 to 15 (mean, 4.3) years was available for seven patients. Three died of disease after 4, 4, and 3 years, and three are alive with disease 2, 2, and 15 years after diagnosis. Two of the latter three patients had extensive local recurrences, one 15 years after the diagnosis of a well-differentiated papillary mesothelioma, the other 2 years following treatment with hydrocelectomy only. One patient who has been followed for only 1 year has no evidence of disease. This series emphasizes a number of important features of testicular mesothelioma; (a) a wide age range with occasional occurrence at a young age, (b) a wide morphologic spectrum with regard to degree of differentiation, and (c) an aggressive natural history with a potential for late recurrence or metastasis of even well-differentiated tumors, suggesting the need for initial aggressive surgical treatment.

An incidental diagnosis of well-differentiated papillary mesothelioma in a woman operated on for recurrent endometriosis

The case presented involves a report of severe endometriosis with recurrent disabling dysmenorrhea associated with well-differentiated mesothelioma. Although the course of mesotheliomas is predominantly benign, the diversity of lesions, variable behavior, and resemblance, and association with endometriosis warrant thorough diagnostic investigation. Multiple biopsies and differential diagnoses are recommended in cases of peritoneal endometriosis.

Pathology of the peritoneum: a review of selected topics.

Mesothelial lesions of the peritoneum may pose significant diagnostic problems. Accurate identification of these lesions is important because of their distinctive behavior and treatment requirements. This review discusses the clinical, pathological, and differential diagnosis of a variety of mesothelial lesions of the peritoneum, which includes mesothelial hyperplasia, multilocular peritoneal inclusion cysts (benign cystic mesothelioma), well-differentiated papillary mesotheliomas, and diffuse malignant mesothelioma, and the role of immunohistochemistry in the distinction from the more common primary peritoneal serous carcinomas. In addition, borderline serous tumors, psammocarcinomas, and solitary fibrous tumors of the peritoneum are briefly mentioned.

Malignant Peritoneal Mesothelioma in Childhood with Long-term Survival

A diffuse, well-differentiated, malignant peritoneal mesothelioma (MPM) developed in a nine-year-old girl. She received limited chemotherapy and radiation therapy and is alive and well without clinical evidence of disease 109 months after diagnosis. The neoplastic cells stained immunohistochemically for cytokeratin and epithelial membrane antigen but were unreactive with B72.3, anti-carcinoembryonic antigen, and anti-Leu-M1. Ultrastructurally, the tumor cells had abundant desmosomes, numerous tonofilament bundles, and variable-length microvilli. These findings confirm the mesothelial nature of the cells. Features consistent with malignancy included DNA aneuploidy by flow cytometric analysis and diffuse peritoneal involvement. The three previously described survivors with MPM were also premenarchal girls. Some MPMs in premenarchal girls have an indolent biologic behavior similar to that of low-grade peritoneal serous neoplasia or well-differentiated papillary mesothelioma in adult women.

Well-differentiated papillary mesothelioma of the peritoneum.

Well-differentiated papillary mesothelioma of the peritoneum.F A Lovell and P E CranstonAudio Available | Share

Well-differentiated papillary mesothelioma of the peritoneum: A borderline mesothelioma

Well-differentiated papillary mesothelioma (WDPM) is considered to be a distinct subtype of peritoneal mesothelioma. Although the WDPM is usually qualified as benign, the natural history of this lesion has not been clearly established. This report relates to two WDPMs which were found incidentally. In a 51-year-old man the WDPM developed over a period of 5 years into a typically malignant diffuse mesothelioma. Thus, although the WDPM morphologically lacks signs of malignancy, it should be regarded as a borderline mesothelioma.

Well-differentiated papillary mesothelioma of the peritoneum. A clinicopathologic study of 22 cases

Twenty-two cases of well-differentiated papillary mesothelioma of the peritoneum (WDPMP) are described. Eighteen of the 22 patients were women. The peritoneal tumor was usually multifocal. Many of the tumors appear to be indolent or inactive and for practical purposes are benign. However, a few patients receiving adjuvant therapy have died under circumstances that make it difficult to determine whether the tumor was responsible for the death. It is suggested that adjuvant therapy be withheld from patients with WDPMP, unless there is clear evidence of progression. The cause of these rare tumors is not apparent, although three patients had had possible exposure to asbestos and two were sisters.