Comparison of oral candidiasis characteristics in head‑and‑neck cancer patients before and during radiotherapy

Abstract

Background: Patients undergoing head‑and‑neck radiotherapy are susceptible to Candida
colonization and infection. This study aimed to identify oral Candida species type (ST), colony
count (CC), and oropharyngeal candidiasis (OPC) in head‑and‑neck cancer patients, undergoing
radiotherapy, before and 2 weeks after radiation.
Materials and Methods: In this quasi‑experimental study, head‑and‑neck cancer patients
undergoing radiotherapy (up to 6000 cGy) were recruited. Samples were taken before and 2 weeks
after radiation therapy (RT). CC was assigned using Sabouraud dextrose agar culture medium
and morphological studies were performed to confirm OPC. For identification, polymerase chain
reaction–restriction fragment length polymorphism was performed. Data were analyzed using
Chi‑square‑test and kappa coefficient. P < 0.05 was considered statistically significant.
Results: Twenty‑one of 33 patients were Candida positive. The detected fungal species included
Candida albicans (60%), Candida tropicalis (22%), Candida glabrata (9%), and other species (9%).
Following RT, OPC and CC changed significantly (P = 0.003 and P = 0.001, respectively), whereas
ST did not significantly change (P = 0.081). Two new species (Candida krusei and Candida parapsilosis)
were detected after the intervention. The OPC, CC, and ST changes after RT were not significantly
related to malignancy site or radiation dose (P > 0.05).
Conclusion: The present study showed that OPC, CC, and ST were not related to the
malignancy site. Following RT, OPC and CC changed significantly, while ST showed no significant
change. The radiation dose and malignancy site had no effects on the OPC, CC, or ST alterations
following RT.
Key Words: Candida, head‑and‑neck neoplasms, radiotherapy