Molecular Detection of Human Papilloma Virus Genotype 16 in Sudanese Patients with Head and Neck Cancers

Abstract

This is a descriptive, retrospective case study was conducted atTotal Lab Care medical laboratories (TLC), department of histopathology and immunohistochemistry during the period from May 2016 to October 2016. The studyaimed to detect the HPV16 infection inhead and neck cancers (HNCs) among Sudanese patients by detecting the viral DNA using PCR technique. Seventy five formalin fixed paraffin embeddedtissue blocks of different head and neck cancer types were collected.From tissue blocks 20 µ were cut by rotary microtome for DNA extraction and then the viral DNA was detected using PCRand agarose gel electrophoresis. The data was analyzed using SPSS program version 16. Frequencies, means and Chi- square test values were calculated. The studyincluded 40 (53.3%) males and 35 (46.7%) females. The ages of patients were ranged between 18 to 80 years with mean age 49±11. Most of patients were more than 40 years representing 57 (76%) and the remaining were less than 40 years representing 18 (24%). The histopathological diagnosis of cases revealed 20 (26.7%) esophageal squamous cell carcinoma (SCC), 15 (20%) nasopharyngeal carcinoma, 9 (12%) tongue SCC, 9 (12%) conjunctival SCC, 3 (4%) mucoepidermoid carcinoma, 3 (4%) adenoid cystic carcinoma, 3 (4%) malignant myoepithelioma, 4 (5.3%) lip SCC, 6 (8%) laryngeal SCC, and 3 (4%) from tonsillar SCC.HPV16 DNA was positive in 13 (17.3%) of samples andnegative in 62 (82.7%) samples. The DNA of HPV16 was detected in males (7/40) and in females (6/35), these results were found to be statistically insignificant (P. value = 0.606). HPV16 DNA wasdetected in 5 (6.7%) in age group less than 40 and 8 (10.7%) in age group more than 40. These results were statistically insignificant (P. value = 0.179). Also HPV16 was detected in 7 (35%) out of 20 of esophageal SCC, 2 (22.3%)out of 9 of tongue SCC,1 out of 3 of adenoid cystic carcinoma (33.4%), and 3 out of 6 (50%) of laryngeal carcinoma. The HPV16 DNA was not detected in nasopharyngeal carcinoma, conjunctival SCC, mucoepidermoid carcinoma, malignant myoepithelioma, lip SCC and tonsillar SCC. These results are shown to be statistically significant (P value = 0.010). From the data presented in current study we concluded that HPV16 infection plays a potential role in the initiation of head and neck cancers.