Impact of HPV 16/18 infection on clinical outcomes in locally advanced cervical cancers treated with radical radio (chemo) therapy - A prospective observational study.

ABSTRACT

OBJECTIVE: With an aim to investigate the impact of Human Papilloma Virus (HPV) 16/18 infection on clinical outcomes in locally advanced cervical cancers treated with radical radio (chemo) therapy, we undertook this prospective study. METHODS: Between May 2010 and April 2012, 150 histologically proven cervical cancer patients treated with radio (chemo) therapy were accrued. Cervical biopsies/brushings were collected at pre-treatment, end of treatment and at 3 monthly intervals up to 24months. Quantitative estimation of HPV 16/18 was done using real-time polymerase chain reaction (RT-PCR) and correlated with various clinical end-points. RESULTS: Out of 150 patients accrued, 135 patients were considered for final analysis. Pre-treatment HPV16/18 DNA was detected in 126 (93%) patients, with HPV-16 present in 91%. The mean log (±SD) HPV-16 and HPV-18 viral load at pre-treatment was 4.76 (±2.5) and 0.14 (±2.1) copies/10ng of DNA, respectively. Though significant decline in viral load was observed on follow-ups (p<0.0001); by 9-month follow-up, 89 (66%) patients had persistence of HPV infection. Patients with persistent HPV 16/18 infection had a significantly higher overall and loco-regional relapses [44/89 (49%) and 29/89 (32%)] as compared to HPV clearance by 9months [12/43 (28%) and 5/43 (11%)] with p=0.024 and p=0.02, respectively. Also, persistent HPV infection by 24-month showed a significant impact on loco-regional control (LRC) and recurrence-free survival (RFS). CONCLUSION: In locally advanced cervical cancers treated with radical radio (chemo) therapy, persistent HPV 16/18 infection is significantly high in immediate post-treatment period and correlated with higher loco-regional, overall relapses and was also associated with early relapses.