Factors affecting adherence to standard cisplatin (CDDP)-based chemotherapy regimen for locally advanced squamous cell head and neck (H&N) cancer in an inner city safety net hospital.

Abstract

252 Background: The non-operative standard of care for advanced, non-metastatic H&N cancer is high dose CDDP (100 mg/m2) given every 21 days for 3 cycles concurrent with radiation. Many patients are either started on or switched to an alternative regimen due to pre-treatment co-morbidities or development of CDDP related toxicity. In clinical practice, the percentage of patients not receiving current standard of care and reasons thereof are not well defined. This and the consequence of such deviation from treatment is what we propose to study. Methods: This is a retrospective study including 45 patients from 2014-2016 with advanced, non-metastatic H&N cancer treated with definitive concurrent chemoradiation. All patients were evaluated by ENT, Medical and Radiation Oncology and were presented to the multidisciplinary H&N Tumor board. Results: In the studied population, 73.3% were African Americans , 82.2 % males, 91.1% smokers and 97.7 % ECOG 0-1 at presentation. In all, 11.1% patients were unable to receive CDDP and received an alternate drug because of frailty, ECOG 2 status, pre-existing CKD, hearing problems or neuropathy. Of the 40 patients (88.8%) receiving CDDP, only 8 (17.7%) completed 3 cycles on schedule without changes. Of the remaining 32 (71.1%) receiving CDDP, 13 (40.6 %) were switched to alternate drug and 19 (59.3%) required only a dose decrease/delay. The reasons included CDDP related toxicity (54.05%), frailty or comorbidities (27%), worsening ECOG and fluid overload due to CDDP associated hydration. Toxicities leading to change in regimen included mostly AKI (63.15%) and also neutropenia, ototoxicity, nausea, vomiting and diarrhea. Mean duration of radiation therapy in patients receiving standard regimen was 52.2 days and in patients deviating from standard regimen was 55.1 days. Data supporting trend of poorer outcomes in those who deviate from standard regimen will be reported later. Conclusions: Majority of patients (82.2%) with advanced, non-metastatic H&N cancer being treated with definitive concurrent chemoradiation deviate from standard of care CDDP regimen with at least half due to cisplatin related toxicity.