Specific genotypes of human papillomavirus in 125 high-grade squamous lesions and invasive cervical cancer cases from Congolese women

Background: Knowledge on HPV prevalence and genotype distribution in HSIL and ICC is highly essential for the introduction of an effective vaccination program and appropriate epidemiological monitoring of viral ecology before and after vaccination in Congo. This study aimed to determine the specific-HPV genotypes in HSIL and ICC among women in southwestern Congo. Methods: 125 archival paraffin-embedded biopsy collected between 2008 and 2012 and histologically diagnosed were investigated. DNA extraction was performed using the phenol/chloroform method. HPV search was performed by nested-PCR using MY09/MY11 and GP5+/GP6+ consensus primers followed by direct sequencing. Results: The mean age of participants was 44.3 +/- 8.2 years. Overall, HPV prevalence was 89.6% (112/125) with all high-risk genotypes. HPV DNA was detected in 81.5% (53/65) of HSIL and 98.3% (59/60) of ICC. HPV 16 the most common genotype was detected in 47.1% (25/53) of HSIL and 52.5% (31/59) of ICC. Other types identified were: HPV 33 (22.6%), HPV 18 (15%), HPV 31 (11.3%) and HPV 69 (3.7%) in HSIL, and HPV 33 (28.8%), HPV 18 (11.8%), HPV 31 (5%) and HPV 35 (1.7%) in ICC. Knowing that the ADC accounted for 6.7% (4/60) of ICC cases, HPV 18 was identified in 25% (1/4) of these cases against 75% (3/4) for HPV 16. Conclusion: Our study showed that HPV 16, 33, 18 and 31 were the four most common genotypes in women with HSIL and ICC. These findings indicate that current vaccines against HPV could help to reduce the burden of cervical cancer in Congo.