Introduction: Background and aims: Colorectal cancer is one of the most important malignant tumor in humans and the third most common cancer in men (after lung and prostate cancer) and the second most common cancer in women (after breast cancer) worldwide. The role of infectious agents and oncoviruses such as human papillomaviruses in contaminating colorectal regions, which can occur as a result of dissemination from contaminated anogenital areas or through blood or lymph, is mentioned as a potential risk factor for colorectal cancer. This study was conducted to determine the prevalence and genotype distribution of human papillomavirus in paraffin-embedded tissue specimens from patients with colorectal cancer in a 9-year period in Bushehr province using nested-PCR technique.
Methods: Materials and Methods: This study is a descriptive cross-sectional study. The study population includes paraffin-embedded colorectal specimens of patients with colorectal cancer referred to the Shohadaie Khalij-Fars Hospital in Bushehr during 2009 to 2018. Of 147 patients, paraffin-embedded tissue specimens from 128 patients with colorectal cancer were investigated for molecular analysis. In addition, 146 non-cancerous paraffin-embedded tissue samples (inflammatory and polyp specimens) were used as control group. Data were analyzed using SPSS software, Chi-square and Fisher's statistical tests.
Results: Results: Out of 128 patients with colorectal cancer, 65 men with a mean age of 59.05 ± 13.05 and 63 women with a mean age of 56.79 ± 15.86 were enrolled. Most of the patients were between the ages of 50- 59 years. Most cases of colorectal cancer were from 2014 and 2015. The overall prevalence of HPV infection in 128 colorectal cancers was 1.56%. Out of 98 samples with colon adenocarcinoma, the prevalence of HPV infection was 1.02% and among 30 cases with adenocarcinoma rectum, the prevalence of HPV infection was 3.33%. Although the prevalence of HPV infection in adenocarcinoma rectum biopsy specimens was higher, the results indicated no significant statistically association between the anatomical location of the tumor and the prevalence of HPV infection. In addition, 146 non-cancerous colorectal specimens including 104 inflammatory and 42 polyp specimens were negative for HPV infection.
Conclusion: Conclusion: The overall prevalence of HPV infection in colorectal cancer samples was low, and there was no significant statistically relationship between age, sex, city, year and anatomical location of cancer with the prevalence of HPV infection (p value> 0.05). Therefore, the role of other risk factors for colorectal cancer such as unhealthy diet, obesity, smoking, genetic factors and environmental factors may be more important than the role of human papillomavirus in the development of colorectal cancer.
Keywords: Human Papillomavirus, Colorectal Cancer, Bushehr province, nested-PCR method