Cervical cancer screening and HPV genotype distribution among asymptomatic patients of Karachi Pakistan

Background: Cervical cancer is the second most prevalent cancer in females worldwide. Human papillomavirus (HPV) infection is a sexually transmitted infection. However, in addition to HPV infection, other factors exist that influence the risk of developing cervical cancer. In Pakistan most women who developed cervical cancer have been infrequently or never screened.

Objective: To determine the prevalence of HPV infection and its subtype profile among asymptomatic patients with pre cancerous cervical intraepithelial lesion.

Methods: In this hospital-based descriptive study, 160 asymptomatic females attending gynecology clinics were subjected to HPV screening after obtaining informed consent. Cervical Scrapings were examined by cytopathology and colposcopic directed biopsies taken. High-grade intraepithelial lesion (HSIL) CIN-2, and Low-grade intraepithelial lesion (LSIL) CIN-1 were selected. Samples were analyzed for the presence of HPV-DNA general and type specific genotype 16 and 18. HPV- DNA was extracted by QIA amp DNA kit protocol and amplification was done by polymerase chain reaction (PCR) and genotyped by type specific primers.

Results: Out of 160, 17 Pap smear tests were positive, 6 (35.3%) with abnormal results (HSIL) CIN-2 were HPV-DNA positive. Among them, 5 (83.3%) had subtype 16 and in 1 (16.7%) case the genotype was undetectable. The remaining 11(6.9%) with pre cancer minimal abnormal (LSIL) CIN-1 presented. Out of them 3 (27.3%) were HPV-DNA positive with subtype 16. Five (45.4%) were followed by repeated pap smear every six months for two years, and the rest of 3 (27.3%) patients refused for the test.

Conclusion: A high incidence of Human papillomavirus (HPV) infection is found in women with pre cancerous lesion of cervix in Pakistani women.