A Multicenter Study of Clinician and Patient Reported Acute and Late Toxicity after Radical (Chemo)Radiotherapy for Non-Endemic Nasopharyngeal Cancer

Abstract

Curative (chemo)radiotherapy ((CT)RT) for Nasopharyngeal cancers (NPC) achieves excellent disease control but is associated with significant late toxicities despite modern treatment delivery. Contemporary late toxicity data, including patient reported outcomes (PROs), is limited in the non-endemic population; we present a large contemporary series of toxicity outcomes and late PROs following treatment of non-endemic NPC. Adult patients completing radical (CT)RT for primary NPC between February 2016 and 2020 at 7 large UK cancer centers were identified on institutional databases. Patients were excluded if they had prior head and neck cancer or prior therapeutic head and neck surgery (except neck dissection). Patients with an active other cancer were excluded from PRO assessment. Demographic, treatment, acute toxicity and outcome data were collected retrospectively from patient records. Disease-free patients were invited to complete an M.D. Anderson Dysphagia Index (MDADI) and University of Washington (UoW) Quality of Life (QoL) PROs questionnaires. A total of 180 eligible patients were identified: 68% male, median age 54 years, 11% ≥70 years. EBV status was positive in 61% (unknown 12%). Patients had stage I (5%), II (22%), III (37%), IV (36%) disease; 95% were performance status ≤1 at baseline. Median follow-up was 31.2 months (range 0-68). A total of 54% received 70Gy in 33-35# and 43% received 65-66 Gy in 30-33#. 66% received induction and 65% received concurrent chemotherapy. 9.5% had residual disease at the first follow-up scan. Subsequent locoregional or distant recurrence occurred in 5% and 12% respectively. At last assessment, 84% patients were alive, 16% had died (of which 70% had active disease). Acute treatment toxicity included: 63% of patients required enteral support (median duration 98 days) with 9% a feeding tube at 1 year post treatment. 18% G3 dermatitis, 53% G3 mucositis. 82% requiring opioids and 40% admitted for symptom management. 90 patients completed the PROs (76% response rate) at a median of 37.8 months post treatment (Table 1). These demonstrate significant QoL detriment: 28% report significant pain, 24% require regular analgesia, and 59% report significant impact on daily activity. This was found to persist at different timepoints (not shown). Excellent cancer survival outcomes are seen in a non-selected, non-endemic NPC population. However significant acute and late toxicity following radical treatment is identified which can profoundly negatively impact QoL in a relatively young cohort. This highlights the importance of ongoing efforts to reduce toxicity and supports the prospective evaluation of potential toxicity sparing technologies, such as proton beam radiotherapy.