Epidemiological distribution of high-risk human papillomavirus genotypes and associated factors among patients with esophageal carcinoma at Bugando medical center in Mwanza, Tanzania.

BACKGROUND

Esophageal carcinoma is a growing concern in regions that have a high incidence of human papillomavirus (HPV) infection such as East Africa. HPV, particularly the high-risk genotypes, is increasingly recognized as a risk factor for esophageal carcinoma. We set out to investigate the prevalence and associated factors of high-risk HPV in formalin-fixed paraffin-embedded (FFPE) tissue blocks with esophageal carcinoma at Bugando Medical Center, a tertiary referral hospital in Mwanza, Tanzania, East Africa.

METHODS

A total of 118 esophageal carcinoma FFPE tissue blocks, collected from January 2021 to December 2022, were analyzed. Genomic DNA was extracted from these tissues, and multiplex polymerase chain reaction (PCR) was performed to detect HPV using degenerate primers for the L1 region and type-specific primers for detecting HPV16, HPV18, and other high-risk HPV genotypes. Data were collected using questionnaires and factors associated with high-risk HPV genotypes were analyzed using STATA version 15 software.

RESULTS

Of the 118 patients' samples investigated, the mean age was 58.3 ± 13.4 years with a range of 29-88 years. The majority of the tissue blocks were from male patients 81/118 (68.7%), and most of them were from patients residing in Mwanza region 44/118 (37.3%). Esophageal Squamous Cell Carcinoma (ESCC) was the predominant histological type 107/118 (91.0%). Almost half of the tissue blocks 63/118 (53.3%) tested positive for high-risk HPV. Among these, HPV genotype 16 (HPV16) was the most common 41/63 (65.1%), followed by HPV genotype 18 (HPV18) 15/63 (23.8%), and the rest were other high-risk HPV genotypes detected by the degenerate primers 7/63 (11.1%). The factors associated with high-risk HPV genotypes were cigarette smoking (p-value < 0.001) and alcohol consumption (p-value < 0.001).

CONCLUSION

A substantial number of esophageal carcinomas from Bugando Medical Center in Tanzania tested positive for HPV, with HPV genotype 16 being the most prevalent. This study also revealed a significant association between HPV status and cigarette smoking and alcohol consumption. These findings provide important insights into the role of high-risk HPV in esophageal carcinoma in this region.