Proximal-type epithelioid sarcoma in the groin presenting as a diagnostic dilemma.

Epithelioid sarcoma is an uncommon soft-tissue sarcoma typically presenting as a subcutaneous or deep dermal mass in the distal extremities of young adults. Lately, a 'proximal' subtype has been described, which occurs in the pelvic and genital areas of somewhat older individuals and tends to behave more aggressively than the conventional subtype. The correct diagnosis of this subtype is essential, since this tumor can be easily mistaken for other malignant tumors that exhibit epithelioid morphology. We report a case of proximal-type epithelioid sarcoma that presented as an inguinal mass in a 47-year-old man. Histologically, the tumor consisted of diffuse sheets of epithelioid cells with scattered rhabdoid morphology. By immunohistochemistry, the neoplastic cells expressed cytokeratin, epithelial membrane antigen, vimentin, CD34, CD99 and showed complete loss of nuclear INI1 protein expression. Fluorescence in situ hybridization was considered borderline for 22q deletion. We present this case to emphasize the importance of diagnosing this uncommon tumor and the role of INI1 immunohistochemistry in establishing the diagnosis.

Lymphoepithelioma-like carcinoma of the urinary bladder: report of a rare case.

Lymphoepithelioma-like carcinoma (LELC) is a rare malignant neoplasm in the urinary bladder, which can histologically mimic lymphoma, poorly differentiated invasive transitional cell carcinoma or poorly differentiated squamous cell carcinoma with a lymphoplasmacytic background. A urinary bladder tumor was identified in a 65-year-old man suffering from hematuria for several weeks. Transurethral biopsy revealed an undifferentiated tumor with prominent lymphocytes and plasma cell infiltration. Immunohistochemical evaluation showed positive staining for cytokeratin and epithelial membrane antigen. Subsequent radical cystectomy showed pure LELC. We present the case to highlight the significance of recognizing this unusual bladder tumor and discuss the important differential diagnosis, treatment options and prognosis.

Morphologic changes in fibroadenoma of breast due to chickenpox: a case report with suspicious cytology in fine needle aspiration smears.

BACKGROUND: Fibroadenomas with stromal giant cell reaction have been described in the literature, but cytologic atypia including giant cell reaction due to chickenpox giving rise to suspicious cytology has not been reported. CASE REPORT: A 25-year-old woman, recovering from chickenpox, presented with a 1.5 x 1.5-cm mass in the lower outer quadrant of her right breast. Fine needle aspiration smears showed sheets of benign ductal cells with overlapping myoepithelial cells and many bipolar bare nuclei. Cells showing nuclear enlargement, prominent nucleoli and multilobated or multinucleated giant cell formation occurred in separate sheets or dispersed among groups of benign ductal cells. Cytodiagnosis was suspicion for malignancy; excision biopsy was advised. Histopathologic examination showed fibroadenoma with evidence of epithelial hyperplasia, nuclear enlargement and multilobated giant cell formation. Atypical ductal cells, including the giant cells, were immunohistochemically positive for epithelial membrane antigen, estrogen receptor and progesterone receptor and negative for smooth muscle actin, indicating epithelial origin. Both cytologic and histologic specimens showed focal positive reaction with HSV-1 and HSV-2 antibodies. Ultrastructural examination of aspirated material revealed cytoplasmic viral particles with characteristic surface projections. CONCLUSION: Herpes zoster virus can produce morphologic alteration mimicking a malignancy. Pathologists should be aware of these changes to avoid a false positive diagnosis.