Anogenital Herpes Simplex Virus Pseudotumor: An Unusual Variant of HSV Infection Simulating Squamous Cell Carcinoma in HIV Patients
EF Krasik, JT Rabban. University of California at San Francisco, San Francisco, CA
Background: Anogenital herpes simplex virus (HSV) infection typically manifests as a shallow ulcer on vulvar, perineal, penile or scrotal skin. Rare cases of tumor-like presentations of HSV in various organs exist. We report a series of anogenital HSV pseudotumors in HIV patients with mass-like features simulating squamous cell carcinoma, emphasizing potential morphologic diagnostic pitfalls.
Design: All anogenital surgical specimens with a diagnosis of HSV were identified from our general surgical pathology files between 1989 and 2009. Clinical and laboratory data were obtained from the patients' charts. Cases were classified as a mass-like lesion or not based on their clinical exam findings; slides and pathology reports were reviewed.
Results: Among 49 surgical specimens of anogenital HSV, 6 patients presented with tumor-like growths (2.8 cm to 10 cm). All 6 were HIV patients (2 female, 4 male; age 43 to 53 years). Pseudotumors arose in the perianal region (4), vulva (1), or scrotum (1). Pre-biopsy clinical suspicion was neoplasm (2), infection (2) or unreported (2). Procedures included local excision (4), wide excision (1), or biopsy (1). Grossly, pseudotumors consisted of bulky, exophytic growths with variable surface erosion. Microscopically, two morphologic zones were noted: A) a superficial layer of pseudocarcinomatous epithelial hyperplasia with an underlying zone of dense lymphoplasmacytic inflammation, exuberant granulation tissue and sparse viral infected cells and B) a deeper dermal layer of dense, well-organized fibrotic tissue containing lymphoid aggregates. A variable degree of ulceration and acute inflammation involved the epidermis. HSV-infected cells were present mostly at the dermal-epidermal junction and their number and distribution was sparse, even with HSV immunohistochemistry. Some tissue sections did not contain any infected cells. Co-infection with cytomegalovirus or fungi was not seen. One case was originally interpreted to be squamous cell carcinoma, but only 1 case contained focal severe squamous dysplasia. Average follow up was 41 months (range 0 to 95 months). Recurrent pseudotumor lesions arose in 4/6 patients.
Conclusions: Anogenital pseudotumor is an unusual form of HSV infection in HIV patients that may pose diagnostic piftalls. Pseudocarcinomatous epithelial hyperplasia can mimic squamous carcinoma in shallow biopsies. Viral infected cells may be sparse, requiring thorough sampling of the mass. Co-existence of squamous dysplasia should also be considered when sampling.
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 213, Wednesday Afternoon