Background: Squamous cell carcinoma of the larynx represents 4.5% of all malignancies. There are known risk factors for laryngeal malignancy. One of them is human papillomavirus affection of the larynx. The risk of laryngeal carcinoma has been increased by Up to 19-fold risk in people with evidence of human papillomavirus (HPV) infection in the larynx.
Aim of the Study: To detect the presence of HPV in patients with SCC of the larynx and to study its relation to tumour grading and lymph node invasion.
Patients and Methods: A Cross-sectional analytic study where detection of HPV 16 in 150 surgical formalin-fixed, paraffin-embedded (FFPE) laryngeal tissue specimens from 150 SCC lesions of patients who underwent surgical treatment at our institute. Detection of HPV is done using the qualitative method of DNA extraction and gel electrophoresis in our institute's medical biochemistry lab. All patients had no other apparent HPV-related infection at the time of examination, whether dermatological or genital.
Results: Examination of the specimens revealed that 6.7% had positive HPV 16 (n = 10), and there was a significant difference in the rate of lymph node invasion between the two groups. HPV-positive cases had a significantly (p = 0.048) higher percentage of positive LNs (40% (n = 4/10)) than HPV-negative cases (28.6% (n = 40/140)) HPV-negative cases had a significantly (p < 0.001) higher percentage of grade-I cancer (18.6% (n = 26)) than HPV-positive cases (0%). Unlikely, there was an insignificant difference (p = 0.210) for grade-II cases (Positive cases (70% (n = 7) and negative cases 64.3% (n = 90)). Contrarily, HPV-positive cases had a significantly (p < 0.038) higher percentage of grade-III/IV cancer (30% (n = 3)) compared with HPV-negative cases (17.3% (n = 24))
Conclusion: HPV affects the grading of carcinoma as HPV-positive cases had a significantly higher percentage of grade-III/IV cancer compared with HPV-negative cases. Also, HPV associated with lymphadenopathy as HPV-positive cases had a significantly higher percentage of positive LNs than HPV-negative cases.