The Oral Carriage of Candida in Oral Cancer Patients of Indian Origin Undergoing Radiotherapy and/or Chemotherapy.

Abstract

Oral cancer is a challenging disease in Indian subcontinent because of increased use of tobacco and associated products. Although surgery is the main treatment modality, radiotherapy (RT) and chemotherapy (CT) are employed in inaccessible cases. Both RT & CT will result in painful and debilitating adverse effects in oral cavity e.g., mucositis, ulceration, dysgeusia, xerostomia and opportunistic infections. One of the most common opportunistic infection is caused by fungus Candida. Our aim was to investigate the incidence of oral colonization of Candida species with differentiation between carrier and infective state of the organism. We also investigate the effect of treatment modality (RT and CT) on the incidence of Candida, in oral cancer patients, undergoing RT and/or CT, in order to prevent and treat the Candida infection in a better way. It was a cross-sectional case-control study; done in Gujarat, India. Fifty patients of oral cancer undergoing RT, CT alone or combined were investigated and compared with the healthy controls. The samples were collected from mid-dorsum of tongue by using imprint culture technique. The samples were inoculated on Sabouraud's dextrose agar medium and the organisms were identified by wet mount, germ tube test, chlamydospore formation and sugar fermentation tests. There was significant increase in oral Candida colonization from 20% in healthy controls to 70% in oral cancer patients undergoing RT and/or CT (p = 0.001, < 0.05). A significant increase in infective state of Candida (71.4%) was noted (p = 0.001, < 0.05) with predominance of non-albicans species of Candida, chiefly C. tropicalis (42.8%). RT and CT leads to increased oral colonization and infection by Candida with a shift towards growth of non-albicans species. As the pattern of candidal species infection is changing, such studies are important for better diagnosis and treatment planning to gain good control over the disease.