Large Cell Calcifying Sertoli Cell Tumor of the Testis: A Case Study and Review of the Literature

A 24-year-old man was admitted due to an incidentally detected mass in his left testis, which showed radiopaque calcification on plain X-ray film. Left orchiectomy was performed, and the resected testis contained a well-demarcated, hard mass measuring 1.1 cm. Histological analysis revealed that the tumor was composed of neoplastic cells, fibrotic stroma, and laminated or irregularly shaped calcific bodies. The individual cells had abundant eosinophilic or clear cytoplasm with round nuclei, each of which contained one or two conspicuous nucleoli. They were arranged in cords, trabeculae, clusters, and diffuse sheets. There were several foci of intra-tubular growth patterns, with thickening of the basal lamina. Immunohistochemically, the neoplastic cells were positive for S-100 protein and vimentin, focally positive for inhibin alpha, and negative for cytokeratin, CD10, and Melan-A. In addition to reporting this rare case, we also review the relevant literature regarding large cell calcifying Sertoli cell tumors.

Aneurysmal Benign Fibrous Histiocytoma with Atrophic Features

Aneurysmal benign fibrous histiocytoma is an uncommon pathologic variant of dermatofibroma. In addition to the features of a typical dermatofibroma, it has large cleft-like or cavernous blood-filled spaces with numerous hemosiderin pigments. It should be differentiated from angiomatoid malignant fibrous histiocytoma, malignant melanoma, and vascular tumors such as Kaposi's sarcoma and angiosarcoma. Atrophic dermatofibroma is also a rare variant of dermatofibroma, and the combination of aneurysmal and atrophic features is rarer still. We report a case of aneurysmal benign fibrous histiocytoma with atrophic features in a 27-year-old male who had a grayish-brown atrophic patchy lesion on his back for 2 years.

CD99 activates T cells via a costimulatory function that promotes raft association of TCR complex and tyrosine phosphorylation of TCR zeta

We investigated the co-stimulatory role of a cell-surface protein, CD99. Co-ligation of CD99 and suboptimal CD3 induced T-cell activation to a level comparable to that obtained with optimal CD3 or CD3+CD28. We also noted concomitant enhancement of the earliest T-cell receptor (TCR) signaling events. In addition, co-ligation of CD99 and CD3 led to translocation of TCR complexes into the lipid raft, without concomitant migration of CD99 to the raft, and consequent enhancement of TCR zeta-mediated signal 1. These data demonstrate the unique properties of CD99 co-stimulation that distinguish this molecule from CD28 and other raft-resident co-stimulatory factors.

Altered Expression of Nephrin, Glomerular Epithelial Cell Protein-1 (GLEPP1) and WT-1 in Glomerular Disease

BACKGROUND: Glomerular epithelial cell protein-1 (GLEPP1) and WT-1 expressed in mature visceral glomerular epithelial cell (VGEC) is required for maintenance of the mature status of VGEC. Nephrin protein is located at the filtration slit and regarded as a molecular component of the slit diaphragm. Alterations of these proteins in proteinuric diseases are not clearly defined. METHODS: We investigated the expression of GLEPP1, WT-1 and nephrin in 28 renal biopsies diagnosed with minimal change nephropathy (n=10), focal glomerulosclerosis (n=10) and membranous nephritis (n=8) by immunohistochemical staining. Normal control biopsies were obtained from six nephrectomy specimens. RESULTS: The patients consisted of 15 males and 13 females. The mean age was 40.7 years. Nephrotic range proteinuria (> or =3.5 g/day) was noted in 15 (54%) patients. GLEPP1 and nephrin expression were significantly decreased in patients as compared with those of the controls (p<0.05). The mean number of WT-1 expressing cells per glomerulus was also significantly decreased in patients as compared with those of the controls (p<0.05). However, there was no significant difference in the number of WT-1 expressing cells among the disease groups. CONCLUSIONS: These results suggest that the loss of biological markers of mature VGEC may play an important role in the pathogenesis of proteinuria.

Expression of Cytokeratin 7 and 20 According to The Anatomical Location of Colon Cancer and The Differential Diagnosis with Cholangiocarcinoma

BACKGROUND:Colonic adenocarcinoma usually shows CK7 negativity and CK20 positivity, which helps to differentiate it from cholangiocarcinoma usually showing a reverse immunohistochemical profile. We immunohistochemically investigated the pattern of CK7 and 20 expressions according to the anatomical location of colon cancer to refine the usefulness of CK expression in differential diagnosis. METHODS: Immunohistochemical staining was done on 90 cases of surgically resected colon cancers and 84 cases of cholangiocarcinomas. RESULTS: When the cases of colon cancer were divided into CATD (from the cecum to the descending colon) (32), sigmoid (26), and rectum (32), the positivity of CK7 was 41%, 15% and 28%, respectively, and the negativity of CK20 was 25%, 0 and 9% (p=0.013), respectively. In sigmoid colon cancers, 22 cases (85%) exhibited CK7-/CK20+ immunophenotype. However, the percentage decreased to 63% in the rectum and 47% in CATD. The CK7+/CK20- immunophenotype was found only in cancers in the cecum and ascending colon. The expression of CK7 was related to histologic differentiation (p=0.017). CONCLUSIONS: The aberrant expressions of CKs were frequent in cancers of the rectum and ascending colon which are located in the transition site from the anus and small bowel, respectively. If adenocarcinoma in the liver were CK7+/CK20+ or CK7-/CK20-, the possibility of metastatic adenocarcinoma from CATD and rectum should be considered.

Polyomavirus Renal Infection Confirmed by Electron Microscopy in a Patient with Acquired Immunodeficiency Syndrome: An Autopsy Case Report

Polyomavirus infection commonly occurs in childhood and adolescence, remaining in a latent status and reactivated in an immunocompromised status. We report herein an autopsy case of HIV-positive 41-year-old male, who succumbed to disseminated Kaposi sarcoma and cytomegalovirus infection involving the gastrointestinal tract, lung and brain. The involved kidney showed minimal inflammatory infiltrates and tubular injury: the nuclei of tubular epithelial cells were markedly enlarged with central clearing and peripheral chromatin margination or bore basophilic nuclear inclusions. Inclusion-bearing tubular epithelial cells were negative for the viral immunostains including herpes simplex virus, Epstein-Barr virus and adenovirus. Electron microscopy disclosed 42 nm intranuclear viral particles compatible with the BK polyomavirus. The viral particles were icosahedral in paracrystalline array and nonenveloped.

Hamartomatous gastric polyposis in a patient with tuberous sclerosis

A 42-year-old female diagnosed with tuberous sclerosis was found to have multiple polyps in the fundus of stomach. On histologic examination, the lesions were hamartomatous polyps. In tuberous sclerosis, many lesions occur in multiple organs and there are several reports about the frequent association of hamartomatous polyps of the colon. However, gastric manifestation of tuberous sclerosis has not been established probably due to its asymptomatic nature. This is the first report of multiple gastric hamartomatous polyposis in patient with tuberous sclerosis.

Hamartomatous gastric polyposis in a patient with tuberous sclerosis

A 42-year-old female diagnosed with tuberous sclerosis was found to have multiple polyps in the fundus of stomach. On histologic examination, the lesions were hamartomatous polyps. In tuberous sclerosis, many lesions occur in multiple organs and there are several reports about the frequent association of hamartomatous polyps of the colon. However, gastric manifestation of tuberous sclerosis has not been established probably due to its asymptomatic nature. This is the first report of multiple gastric hamartomatous polyposis in patient with tuberous sclerosis.

Colorectal adenocarcinoma as a second malignant neoplasm following rhabdomyosarcoma of the urinary bladder: a case report

Following improvements in therapy for childhood malignancies, the striking increase in survival rate over the past 30 years has led to the increase risk of developing second malignant neoplasms (SMNs). We report a case of colorectal carcinoma as a SMN, following treatment for rhabdomyosarcoma. The patient was diagnosed with rhabdomyosarcoma of the urinary bladder at his age of three years, and developed adenocarcinoma in the colon 13 years later. Histologic examination of the surgical specimen revealed adenocarcinoma involving the rectosigmoid area with radiation colitis in its background. The tumor cells showed strong immunoreactivity for p53 protein, suggesting the role of irradiation and p53 mutation in carcinogenesis. This case emphasizes the need for dose observation in survivors of early childhood malignancies treated with radiation and multiagent chemotherapy.

Colorectal adenocarcinoma as a second malignant neoplasm following rhabdomyosarcoma of the urinary bladder: a case report

Following improvements in therapy for childhood malignancies, the striking increase in survival rate over the past 30 years has led to the increase risk of developing second malignant neoplasms (SMNs). We report a case of colorectal carcinoma as a SMN, following treatment for rhabdomyosarcoma. The patient was diagnosed with rhabdomyosarcoma of the urinary bladder at his age of three years, and developed adenocarcinoma in the colon 13 years later. Histologic examination of the surgical specimen revealed adenocarcinoma involving the rectosigmoid area with radiation colitis in its background. The tumor cells showed strong immunoreactivity for p53 protein, suggesting the role of irradiation and p53 mutation in carcinogenesis. This case emphasizes the need for dose observation in survivors of early childhood malignancies treated with radiation and multiagent chemotherapy.