Darren M C Poon1,2, Michael K M Kam2, David Johnson1, Frankie Mo1, Macy Tong1, Anthony T C Chan1. 1. Department of Clinical Oncology, State Key Laboratory of Translational Oncology, Sir YK Pao Centre for Cancer, Hong Kong Cancer Institute and Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China. 2. Comprehensive Oncology Centre, Hong Kong Sanatorium & Hospital, Hong Kong, China.
Abstract
BACKGROUND: The durability of improved xerostomia with intensity-modulated radiotherapy (IMRT) in patients with early stage nasopharyngeal carcinoma (NPC) is uncertain. We conducted a long-term prospective assessment of participants treated withIMRT or two-dimensional radiotherapy (2DRT) in a prior randomized study. METHODS:Parent study participants (IMRT, n = 28; 2DRT, n = 28) who were free of second malignancy or recurrence were eligible. Long-term radiotherapy-related toxicities were graded according to the Radiation Therapy Oncology Group (RTOG) criteria. Long-term patient-reported outcomes were assessed by the six-item xerostomia (XQ) and two European Organisation for Research and Treatment of Cancer (EORTC) questionnaires (QLQ-C30, QLQ-H&N35). Overall survival (OS), locoregional relapse-free survival (LRFS), distant relapse-free survival (DRFS), and the rate of symptomatic late complications (SLCs) were estimated for the entire cohort (n = 56). RESULTS: Totally, 21 (IMRT, n = 10; 2DRT, n = 11) patients gave consent and were assessed for an overall median follow-up of 15.5 years. There was significantly less RTOG ≥grade 2 xerostomia with IMRT versus 2DRT (20% vs. 90%; p = 0.001), but no significant difference in XQ scores. Patients in the IMRT arm reported lower mean scores for the "dry mouth" domain of EORTC QLQ-H&N35 (p = 0.02) and showed trends toward better 15-year OS (81.5% vs. 53.8%, p = 0.06), LRFS (70.6% vs. 53.8%, p = 0.38), and DRFS (81.5% vs. 53.8%, p = 0.07). SLCs were more frequent in the 2DRT arm. CONCLUSIONS: The parotid-sparing effect of IMRT in NPC treatment is durable, with significantly less physician- and patient-scored xerostomia at 15 years. IMRT results in better long-term survival and fewer SLCs.
RCT Entities:
BACKGROUND: The durability of improved xerostomia with intensity-modulated radiotherapy (IMRT) in patients with early stage nasopharyngeal carcinoma (NPC) is uncertain. We conducted a long-term prospective assessment of participants treated with IMRT or two-dimensional radiotherapy (2DRT) in a prior randomized study. METHODS: Parent study participants (IMRT, n = 28; 2DRT, n = 28) who were free of second malignancy or recurrence were eligible. Long-term radiotherapy-related toxicities were graded according to the Radiation Therapy Oncology Group (RTOG) criteria. Long-term patient-reported outcomes were assessed by the six-item xerostomia (XQ) and two European Organisation for Research and Treatment of Cancer (EORTC) questionnaires (QLQ-C30, QLQ-H&N35). Overall survival (OS), locoregional relapse-free survival (LRFS), distant relapse-free survival (DRFS), and the rate of symptomatic late complications (SLCs) were estimated for the entire cohort (n = 56). RESULTS: Totally, 21 (IMRT, n = 10; 2DRT, n = 11) patients gave consent and were assessed for an overall median follow-up of 15.5 years. There was significantly less RTOG ≥grade 2 xerostomia with IMRT versus 2DRT (20% vs. 90%; p = 0.001), but no significant difference in XQ scores. Patients in the IMRT arm reported lower mean scores for the "dry mouth" domain of EORTC QLQ-H&N35 (p = 0.02) and showed trends toward better 15-year OS (81.5% vs. 53.8%, p = 0.06), LRFS (70.6% vs. 53.8%, p = 0.38), and DRFS (81.5% vs. 53.8%, p = 0.07). SLCs were more frequent in the 2DRT arm. CONCLUSIONS: The parotid-sparing effect of IMRT in NPC treatment is durable, with significantly less physician- and patient-scored xerostomia at 15 years. IMRT results in better long-term survival and fewer SLCs.
Authors: Sebastien A A Gros; Anand P Santhanam; Alec M Block; Bahman Emami; Brian H Lee; Cara Joyce Journal: Front Oncol Date: 2022-06-30 Impact factor: 5.738