Anal Fibroepithelial Polyp With Epithelial Vascular Pseudoinvasion.

In this article, we report a case of anal fibroepithelial polyp with benign squamous cell vascular pseudoinvasion. The patient was a 38-year-old Caucasian man, who presented at our institution for recurrent episodes of anal discomfort. Clinical evaluation revealed the presence of 2 pedunculated anal polyps that were resected and submitted for histological evaluation. On microscopic evaluation, one of the polyps shows epithelial endovascular displacement associated with morphological signs of traumatism. The differential diagnosis and possible pathogenetic mechanisms explaining the presence of such findings are discussed. To the best of our knowledge, this is the first case reported of an anal fibroepithelial polyp with epithelial vascular pseudoinvasion.

Multifocal capillary hemangioma (hemangiomatosis) of the spleen.

BACKGROUND: The spleen is mainly affected by benign tumors that originate from the vascular endothelium. The most common is hemangioma, which presents as a small, localized lesion. Isolated diffuse hemangiomatosis of the spleen is a rare entity in which the entire splenic parenchyma is replaced by a proliferation of neoplastic blood vessels. Here we illustrate the case of a 26-year-old man presenting with splenomegaly due to diffuse hemangiomatosis of the white pulp who underwent a splenectomy. METHODS: Representative samples of the spleen were stained with hematoxylin and eosin, and immunohistochemical analysis was performed for Mib-1, CD20, CD30, CD15, CD34, CD31, CD8, factor VIII, D2-40, CD68PGM1, and LMP1. RESULTS: Macroscopically, the splenic parenchyma contained multiple, red-brown nodules ranging from 0.4 to 1.5 cm. Microscopically, the nodules were roundish and confluent with an angiomatoid appearance and high positivity for CD34 and factor VIII, while they were negative for D2-40. CONCLUSIONS: The differential diagnosis of splenic tumors includes lymphangioma, lymphangiomatosis, peliosis, littoral cell angioma, hemangioendothelioma, hamartoma, angiomatoid transformation of the spleen, and angiosarcoma. It is debated whether diffuse hemangiomatosis is a malformation of the postsinusoidal venous system or a slowly growing neoplasm arising from the splenic sinuses. The positivity of the cavernous vessels for CD8 seems to be in favor of the malformative nature of the tumor.

Rheumatoid nodule and combined pulmonary carcinoma: topographic correlations; a case report and review of the literature.

An association between rheumatoid arthritis (RA) and malignancies has been ascertained and patients with RA appear to be at higher risk of lymphoma and lung cancer. The higher risk of the latter malignancy may be related to rheumatoid interstitial lung disease and immunosuppressive therapies. Herein we illustrate the case of a 59-year-old male smoker affected by RA and treated with cortisone, methotrexate and TNF-α antagonists, who underwent right lower lobectomy for a nodular lesion. On microscopic examination, the lesion consisted of two distinct areas: a central area of fibrinoid necrosis, bordered by histiocytes in a palisaded arrangement, lymphocytes and a 0.4 cm thick peripheral area constituted by a combined small cell anaplastic carcinoma, adenocarcinoma and squamous cell carcinoma. The combination of three histotypes is very rare in such a small tumour. In our case, it may be hypothesized that synchronous, heterogeneous mutations occurred in different type of committed cells or in stem cells, due to the production of cytokines by RA nodule histiocytes and lymphocytes, which are contiguous to the carcinomatous area. Since few studies have evaluated the topographic correlation between tumors and rheumatoid lung lesions, further morphological and molecular studies are needed to clarify this association and the pathogenetic relationship between RA and cancer of the lung.