The diagnostic utility of human papillomavirus-testing in combination with immunohistochemistry in advanced gynaecologic pelvic tumours: a new diagnostic approach.

Gynaecologic pelvic tumours comprise a range of histological entities that are highly variable with respect to their clinical behaviour. The distinction of these tumours can be extremely difficult. Accurate identification of the primary tumour site has significant impact on the treatment strategy and prognosis. In this study we investigated the diagnostic and clinical utility of HPV (Human Papillomavirus)-testing in combination with selected immunohistochemical markers in advanced pelvic tumours of unknown primary origin. Specimens of eight patients who presented with advanced gynaecologic pelvic tumour of unknown primary origin, 10 unequivocal cervical carcinomas with 10 corresponding metastases and 10 unequivocal endometrial carcinomas with 4 corresponding metastases were studied. All cases were analysed for HPV-infection by PCR. The expression of CEA, vimentin (VIM), estrogen receptor (ER) and progesterone receptor (PR) was studied by immunohistochemistry. HPV-DNA was exclusively detected in cervical carcinomas and their corresponding metastases but in none of the endometrial carcinomas (Fisher's exact test p<0.001). Endometrial carcinomas and their metastases were generally positive for ER (86%), PR (93%) and VIM (100%) but rarely positive for CEA (14%) and HPV (0%). Most cervical carcinomas and their corresponding metastases were positive for CEA (79%) and HPV (89%). They rarely expressed ER (5%), PR (5%) and VIM (10%). Among the eight patients with unknown primary tumour four patients were diagnosed with a cervical carcinoma and four with an endometrial carcinoma. In one case we could exclude an ovarian carcinoma. Immunohistochemical analysis of selected markers in combination with HPV-testing is simple and inexpensive. The detection of HPV-DNA seems to provide the most compelling evidence for the primary tumour site, when immunohistochemical analysis is less definitive. The proposed diagnostic approach is helpful in the identification and management of pelvic tumours of unknown primary origin.