Radiotherapy has been recognized as a valuable modality of treatment in the management of head and neck cancers. It can have a direct bactericidal effect on the normal flora of the oropharynx. The objective of this study is to determine the changes in the oropharyngeal flora after external beam radiation. This prospective non randomized control study was performed to aid in identification of organisms involved in sepsis, as well as aid in choosing appropriate antibiotics for surgical procedures in irradiated patient. Forty patients with various head and neck malignancy and thirty control patients were selected. Oropharyngeal swabs were taken prior to radiotherapy, at the end and one month after radiotherapy. A single swab was taken from the control group. A full bacteriological analysis was performed. There was a statistically significant decrease in Alpha Hemolytic Streptococci and Neisseria species post radiotherapy. B Proteus and Candida Albicans showed a statistical significant increase in patients with head and neck cancer post radiotherapy. These changes remained even one month after radiotherapy.
Expression of the Epstein-Barr virus (EBV) encoded nuclear antigens (EBNA 1 to 6) and membrane-associated protein (LMP) was investigated by immunoblotting in 83 nasopharyngeal carcinoma (NPC) biopsies and 25 other tumor and normal tissue specimens from the head and neck region. Fifty-eight of the 83 NPC biopsies were large enough to yield parallel data on virus DNA and viral expression. All 16 cases of clinically diagnosed and histologically confirmed NPCs from North Africa contained EBV DNA and expressed EBNA-1. Of 31 clinically diagnosed NPCs from China, 29 contained EBV DNA and 25 of these expressed EBNA-1. One control tissue biopsy from the oropharynx of NPC patients contained EBV DNA, but none expressed EBNA-1. The latent membrane protein (LMP) was detected in 22/31 of the Chinese and in 10/16 of the North African NPC biopsies. None of the NPC biopsies or control tissues expressed detectable amounts of EBNA 2 or any of the other 4 nuclear antigens which are invariably expressed in EBV-transformed B cells. A smaller number of tumors from Malaysia and East Africa exhibited a similar pattern of expression. EBV was rescued from a nude-mouse-passaged North African NPC tumor by co-cultivation of the tumor cells with umbilical cord blood lymphocytes. The tumor expressed EBNA 1 and LMP, but not EBNA 2 or the other 4 EBNAs. The resulting LCLs expressed all 6 nuclear antigens, EBNA 1 to 6 and LMP. Our data suggest that expression of the EBV genome is regulated in a tissue-specific fashion.