[Pseudoangiosarcomatous squamous cell carcinoma of the penis: a case report with clinicopathological and human papilloma virus analyses].

OBJECTIVE: To further understand the clinicopathological, ultrastructural and molecular features of penile pseudoangiosarcomatous squamous cell carcinoma (PASCC), and improve its diagnosis and treatment.

METHODS: A 47-year-old male patient with penile PASCC was reported and the relevant literature reviewed. The main clinical manifestations of the patient were a typical surface ulceration with hemorrhage and purulent secretion with a foul smell, a papillary mass about 5.0 cm x 5.0 cm x 4.0 cm for 1 year on the foreskin of the penis, and 3 enlarged bilateral inguinal lymph nodes. CT scanning showed no enlarged lymph nodes in the abdomen and pelvis, and X-ray examination revealed no abnormality in the chest.

RESULTS: The diagnosis was established by biopsy. Partial penectomy and bilateral inguinal lymphadenectomy (T2N2M0) were performed, followed by adjuvant pelvic radiotherapy. Two months later, total penectomy was necessitated by penile flap necrosis and local recurrence. Eleven months after the first surgery, the patient died of extensive metastasis to the pelvis and lungs. Under the light microsope, the tumor was mainly composed of vessel-like lacunar reticularis spindle cells and a few local squamous cancer cells. Careful examination revealed some focal areas with evident transition from squamous nests to the more acantholytic areas extending towards the pseudoangiosarcomatous spaces. Pathogenetically, it appeared to be the variant of acantholytic squamous cell carcinoma. Immunohistochemically, most tumor cells were strongly positive for keratin (AE1/AE3) and focally positive for EMA, with the typical squamous cells focally positive for 34betaE12 and vimentin. The vessels that proliferated in the tumor were decorated by CD31, CD34 and factor VIII-related antigens, but the tumor cells were negative for HMB45, SMA, Desmin and CEA. HPV DNA (HPVpan, HPV6B/11, HPV16/18, HPV31/33) was not detected by in situ hybridization in the primary and metastatic tumors.

CONCLUSION: PASCC is a specific and extremely rare subtype of penile SCC with dramatic similarity to angiosarcoma under the microscope, with poor prognosis. Its diagnosis depends on histopathological, immunohistochemical and ultrastructural studies. Such a presentation underscores the importance of timely consultation, early diagnosis and prompt treatment.