ANALYSIS OF THE EFFECTIVENESS AND TOXICITIES OF WEEKLY ADJUVANT CHEMOTHERAPY IN HEAD AND NECK SQUAMOUS CELL CARCINOMA

Introduction: Head and neck cancer (HNC) have a high incidence in Brazil, representing more than 8% of tumors in males. Patients presenting respectable lesions (stage III and IV) are treated with surgery followed by adjuvant chemo-radiotherapy with high-dose cisplatin (CDDP). This regiment has been considered standard of care for several years, but it has high toxicity. Therefore, low-dose chemotherapy with CDDP on a weekly can also be used. Objective: The objective is evaluate the efficacy of adjuvant treatment with weekly CDDP (40mg/m2) in patients with HNC ineligible for standard regimen (100mg/m2) and o identify the most frequent contraindications and toxicity. Methods: The project was approved by the local IRB. This is a retrospective, longitudinal cohort study that includes patients with head and neck squamous cell carcinoma, excluding nasopharynx, stage III and IV, who underwent surgical resection in the period from January 2014 to December 2018. A collection form was created on institutional REDCap to collect toxicity data and clinical outcomes. Results: Forty-three patients with a mean age of 60 years were included, with a predominance of males (74.4%), smokers or former smokers (95.3%), drinkers or former drinkers (67.4%), and primary laryngeal site (44.2%). Most patients (60.5%) had comorbidities. The main reason for the contraindication of high-dose cisplatin was renal function (48.8%). Of those, 37.2% were able to complete treatment without dose suspension or delay of chemotherapy or radiotherapy sessions. The main reason for treatment discontinuation was nephrotoxicity (34.8%) and myelotoxicity (23.2%). The progression-free survival for 1, and 3 years was 55.6% and 11.1%, respectively. The overall survival for 1, 3, and 5 years was 82.2%, 66.8%, and 58.3%, respectively. Conclusion: This study provides evidence that weekly CDDP is an option, especially in those patients with some contraindication to high-dose cisplatin, since it presents greater tolerability and fewer side effects, and maintaining more effective results than radiotherapy alone.