HUMAN PAPILLOMAVIRUS INFECTION AND CERVICAL-CANCER IN BRAZIL - A RETROSPECTIVE STUDY

Two hundred and thirty paraffin-embedded biopsies obtained from female cervical lesions were tested for the presence of human papillomavirus (HPV) types 6/11, 16/18 and 31/33/35 DNA using nonisotopic in situ hy bridization. Specimens were classified according to the Bethesda Syste m in low grade squamous intraepithelial lesion (LSIL), high grade SIL (HSIL) and squamous cell carcinoma (SCC). HPV prevalence ranged from 9 2.5% in LSIL to 68.5% in SCC. Benign types were prevalent in LSILs whi le oncogenic types infected predominantly HSILs and SCC. HPV infection showed to be age-dependent, but no significant relation to race has b een detected. Patients were analyzed through a five-year period. 20.7% of the lesions spontaneously regressed while 48.9% persisted and 30.4 % progressed to carcinoma. Patients submitted to treatment showed a 19 .4% recurrence rate. High risk types were present in 78.6% (CrudeOR 13 .8, P=0.0003) of the progressive lesions, and in 73.7% of the recurren t SILs (COR 19.3, P=0.0000001). Possible co-factors have also been eva luated: history of other sexually transmitted diseases showed to be po sitively related either to progression (Adjusted OR 13.0, P=0.0002) or to recurrence (AOR 17.2, P=0.0002) while oral contraceptive use and t obacco smoking were not significantly related to them (P>0.1). Associa tion of two or move co-factors also proved to be related to both progr ession and recurrence, indicating that they may interact with HPV infe ction in order to increase the risk of developing malignant lesions.