Abstract A17: Human papillomavirus type 16 and 18 viral loads as predictors associated with abnormal cervical cytology among women in Saudi Arabia

Abstract

Abstract The present study aimed to screen for and genotype HPV among Saudi women; develop sensitive quantitative polymerase chain reaction (qPCR) assays to detect the viral load for the two most common HPV types, namely 16 and 18; and assess whether HPV viral load could be used as a marker for cervical abnormality and disease progression. This study examined 733 specimens (both formalin-fixed, paraffin-embedded specimens and PAP smear samples) from women who underwent cervical screening. The specimens and samples were processed for DNA extraction and then tested for HPV DNA. Approximately 165 specimens (18%) were positive for HPV. Those specimens were genotyped using a reverse line blotting hybridization assay. The results indicated that the most common HPV types detected were a single infection with HPV 16 (51%) or with HPV 18 (28%) followed by infections with multiple HPV types (~7%). A qPCR TaqMan assay developed in-house was used to determine the viral load for HPV genotypes 16 (n=80) and 18 (n=45). Viral loads for both HPV types were significantly associated with cervical cytology grade (P < 0.05). The odds ratio (OR) for the HPV 16 viral load was high for specimens with cervical cancer (OR, 18.8; 95% CI, 4.3–82.9) or for those with high-grade squamous intraepithelial lesions (OR, 14.7; 95% Cl, 2.43–88.49). For the HPV 18 viral load, the OR was significant only for specimens with cervical cancer (OR, 11.1; 95% Cl, 2.2–54.9). Logistic regression models for HPV 16 and for HPV 18 viral load levels were significant, with higher viral load associated with cervical abnormalities. These findings indicate that viral load is a predictor significantly associated with cytology abnormality in women who are positive for high-risk HPVs and suggest integrating a viral load test into current clinical screening practices for HPV-positive women. Citation Format: Dalia Obeid, Shihana Almatrrouk, Hadeel Khayat, Turfah Al-Muammer, Asma Tullbah, Ismail Albadawi, Mohammed Alahdal, Fatimah Alhamlan. Human papillomavirus type 16 and 18 viral loads as predictors associated with abnormal cervical cytology among women in Saudi Arabia [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr A17.