Epstein-Barr virus-associated smooth muscle tumor presenting as a vulvar mass in an acquired immunodeficiency syndrome patient: a case report.

Smooth muscle tumors in immunocompromised patients have a strong association with Epstein-Barr virus (EBV) infection. EBV-associated smooth muscle tumors (EBV-SMT) are considered as a distinct group of smooth muscle tumors with different clinicopathologic features from conventional smooth muscle tumors. A 31-year-old female patient presented with a 2-cm mass at the left labium majus, the clinical diagnosis of which was a Bartholin lesion. She had acquired immunodeficiency syndrome diagnosed 29 months before. Excisional biopsy revealed a cellular tumor composed of round- to spindle-shaped cells with mild to moderate nuclear atypia. The tumor cells were immunoreactive for smooth muscle actin and muscle actin (HHF-35). Evidence of EBV infection was confirmed by in situ hybridization for EBV-encoded small RNA-1. To our knowledge, this is the first case of EBV-SMT presenting as a vulvar mass. EBV-SMT should be included in the differential diagnoses of mesenchymal tumor in patients with immunosuppression and in the differential diagnoses of smooth muscle tumor in uncommon sites, including the vulva.

Oral non-Hodgkin lymphomas: studies of EBV and p53 expression.

OBJECTIVES: The aims of the study were to assess sociodemographic and clinicopathologic characteristics of patients with oral non-Hodgkin lymphomas (NHLs) and the expression of Epstein-Barr virus (EBV) and p53. MATERIALS AND METHODS: The clinical and pathologic features of 11 patients with oral NHLs were studied. The expression of EBV mRNA and p53 protein were studied by means of in situ hybridization and immunohistochemical methods in 11 formalin-fixed, paraffin-embedded specimens from these patients. RESULTS: The patients' age ranged from 13 to 70 years with the mean of 42 years. Human immuno-deficiency virus (HIV) status was documented in five of the 11 patients and three were known to be HIV-positive. The most common locations were gingiva and alveolar mucosa. Pain and tenderness were major symptoms of the patients. The most common histologic subtype was diffuse large-cell, intermediate-grade NHL. Eight of 11 cases (72.7%) showed positive expression of p53 protein. Four of 10 cases (40%) expressed EBV-encoded RNA (EBER) transcripts. All known HIV-positive cases were EBV-positive. CONCLUSIONS: The findings suggest that appropriately expressed p53 protein may play a role in tumorigenesis of oral NHLs. In addition, EBV may be involved with the pathogenesis of oral NHLs particularly in patients with HIV infection.

Immunohistochemistry for intestinal ganglion cells and nerve fibers: aid in the diagnosis of Hirschsprung's disease.

Hirschsprung's disease is a disease of congenital abnormalities characterized by absence of the enteric ganglion cell of the colon. To make a definite diagnosis, biopsy of the aganglionic zones of colon is required. A specimen from submucosal biopsy of the colon is very small and difficult to identify submucosal ganglion cells. Our study reports an immunohistochemical technique to detect submucosal ganglion cells. Six antineural markers, peripherin, cathepsin D, PGP 9.5, synaptophysin, chromogranin and S-100 protein, were used. The best antibody for the detection of submucosal ganglion cells in our study was peripherin. The additional measurement of nerve fiber caliber using S-100 protein staining is a valuable aid in the diagnosis of Hirschsprung's disease. It can be applied to the suction submucosal biopsy in a patient suspected of having Hirschsprung's disease, therefore, the complicated full thickness colonic and rectal biopsy can be avoided.