Cancer Management and Research (Mar 2022)
High Superior-Middle Pharyngeal Constrictor Muscle Mean Dose Correlates with Severe Late Lung Infection and Survival in Nasopharyngeal Cancer Patients
Abstract
Wen-Shan Liu,1– 3 Ju-Chun Chien,1 Yu-Hsien Huang,1 Po-Chun Chen,4,5 Wei-Lun Huang,1 Shao-Wei Chiang,1 Ching-Chih Lee,6 Bor-Hwang Kang,3,6 Yu-Chang Hu1 1Department of Radiation Oncology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; 2Department of Nursing, Meiho University, Pingtung, Taiwan; 3School of Medicine, National Defense Medical Center, Taipei, Taiwan; 4Department of Radiation Oncology, Pingtung Christian Hospital, Pingtung, Taiwan; 5Graduate Institute of Bioresources, National Pingtung University of Science and Technology, Pingtung, Taiwan; 6Department of Otorhinolaryngology - Head and Neck Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, TaiwanCorrespondence: Wen-Shan Liu, Department of Radiation Oncology, Kaohsiung Veterans General Hospital, No. 386, Dazhong 1st Road, Zuoying Dist., Kaohsiung City, 813414, Taiwan, Tel +886934075313, Email [email protected]: The study aimed to evaluate 1) the correlation of doses of swallowing-related organs at risk (OAR) with severe swallowing-related late adverse effects (AE) in nasopharyngeal carcinoma (NPC) patients and 2) the effect of high mean doses of OARs on overall survival (OS).Patients and Methods: This retrospective cohort study enrolled non-metastatic Stage I–IV NPC patients from January 2012 to June 2017. OAR mean doses and severe (≥G3) swallowing-related late AE (xerostomia, dysphagia, and lung infection) were evaluated by t-test and validated using receiver operating characteristic curves. The risk factors of OS were calculated by Cox regression methods.Results: This study enrolled 185 (43 female, 142 male) NPC patients, mean age 52.4 years, primarily with Stage III (93, 50.3%) or Stage IV (67, 36.2%) disease. The mean doses of pharyngeal constrictor muscle (PCM), superior-middle PCM (SMPCM), and superior PCM (SPCM) were significantly higher in those with severe (≥G3) lung infection than in those without (65.7 vs 62.2 Gy, p = 0.036; 68.1 vs 64.2 Gy, p = 0.015; and 70.0 vs 65.9 Gy, p = 0.012, respectively). Patients with severe (≥G3) dysphagia had significant higher mean doses of base of tongue (56.2 vs 50.2 Gy, p = 0.008), laryngeal box (50.6 vs 46.4 Gy, p = 0.036), PCM (65.4 vs 62.1 Gy, p = 0.008), SMPCM (67.1 vs 64.2 Gy, p = 0.014), and SPCM (69.3 vs 65.8 Gy, p = 0.004). Mean SMPCM dose > 64.9 Gy (adjusted hazard ratio [aHR] = 3.2, 95% confidence interval [CI] 1.2– 8.8, p = 0.021), age > 62 years (aHR = 2.7, 95% CI 1.1– 6.9, p = 0.032), N3 status (aHR = 4.0, 95% CI 1.8– 9.0, p = 001), and severe late AE of lung infection (aHR = 4.6, 95% CI 1.5– 14.0, p = 0.007) significantly affected OS.Conclusion: Severe lung infection and dysphagia were associated with significantly higher mean doses of PCM, SMPCM, and SPCM. Among these OARs, only a high SMPCM mean dose was a risk factor for OS in NPC patients.Keywords: nasopharyngeal carcinoma, late adverse effect, pneumonia, dysphagia, pharyngeal constrictor muscle, intensity-modulated radiotherapy
