Patients and sample specimens

The study was carried out at the Institute of Medical Sciences, Banaras Hindu University (BHU), Varanasi, India. The study protocol was approved by the Institutional Ethics Committee. Informed consent was obtained from each individual who attended the Department of Surgical Oncology, SS Hospital, BHU, during the period from February 2012 to January 2014 for treatment. Initially a series of 40 HNC and 37 HND patients were recruited, but after histopathological confirmation this number finally turned out to be 60 and 17 patients, respectively. Patients with cancer in regions other than the head and neck, those with any systemic diseases, and those with infections were excluded from the study. Tissue samples were obtained immediately after resection, snap-frozen, and stored in liquid nitrogen for assay.