Human Papillomavirus Genotype Distribution in Invasive Cervical Cancer in Pakistan.

Area of Science:

• Oncology
• Virology
• Public Health

Background:

• Few studies have investigated the burden of human papillomavirus (HPV) infection in Pakistan.
• Invasive cervical cancer (ICC) remains a significant health concern globally, with HPV being the primary causative agent.

Purpose of the Study:

• To determine the HPV-type distribution in invasive cervical cancer (ICC) cases in Pakistan.
• To compare HPV prevalence and type distribution in Pakistan with regional and global data.
• To assess the potential impact of HPV vaccination on ICC prevention in Pakistan.

Main Methods:

• Analysis of 280 formalin-fixed paraffin-embedded tissue blocks from ICC patients in Pakistan.
• Detection of HPV-DNA using SPF10 broad-spectrum PCR, DNA enzyme immunoassay, and LiPA25 for genotyping.

Main Results:

• HPV-DNA prevalence was high at 87.5% in ICC cases, predominantly squamous cell carcinoma (96.1%).
• Single HPV infections were most common (95.9%), with HPV16 being the predominant type, followed by HPV18 and HPV45.
• Pakistan showed a significantly higher contribution of HPV16/18 (78.4%) compared to Asia and worldwide data, and a lower contribution of other high-risk HPV types.
• HPV18 or HPV45 positive ICC cases were diagnosed at a younger mean age (43.3 and 44.4 years) compared to HPV16 positive cases (50.5 years).

Conclusions:

• High HPV-DNA prevalence and a significant burden of HPV16/18 underscore the need for targeted cervical cancer prevention strategies in Pakistan.
• The findings suggest that current HPV vaccines could potentially prevent a substantial number of new ICC cases in Pakistan.
• Integrated national efforts for cervical cancer screening and HPV vaccination are recommended for Pakistan, where such programs are currently lacking.