The Effect of Hospital Case Volume on Clinical Outcomes in Patients with Nasopharyngeal Carcinoma: A Multi-institutional Retrospective Analysis (KROG-1106)

• Published in: Cancer research and treatment 2019, 51(1), , pp.12-23
• Main Authors: Ha, Boram, Cho, Kwan Ho, Moon, Sung Ho, Lee, Chang-Geol, Keum, Ki Chang, Kim, Yeon-Sil, Wu, Hong-Gyun, Kim, Jin Ho, Ahn, Yong Chan, Oh, Dongryul, Noh, Jae Myoung, Lee, Jong Hoon, Kim, Sung Hwan, Kim, Won Taek, Oh, Young-Taek, Kang, Min Kyu, Kim, Jin Hee, Kim, Ji-Yoon, Cho, Moon-June, Kay, Chul Seoung, Choi, Jin Hwa
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Dose Fractionation, Radiation; Female; Hospitals, High-Volume - statistics & numerical data; Hospitals, Low-Volume - statistics & numerical data; Humans; Male; Middle Aged; Nasopharyngeal Carcinoma - pathology; Nasopharyngeal Carcinoma - radiotherapy; Nasopharyngeal Neoplasms - pathology; Nasopharyngeal Neoplasms - radiotherapy; Neoplasm Staging; Original; Propensity Score; Radiotherapy, Conformal; Radiotherapy, Intensity-Modulated; Retrospective Studies; Survival Analysis; Treatment Outcome; Young Adult; 의약학
• ISSN: 1598-2998; 2005-9256
• DOI: 10.4143/crt.2017.273

The purpose of this study was to investigate the effect of hospital case volume on clinical outcomes in patients with nasopharyngeal carcinoma (NPC). Data on 1,073 patients with cT1-4N0-3M0 NPC were collected from a multi-institutional retrospective database (KROG 11-06). All patients received definitive radiotherapy (RT) either with three-dimensional-conformal RT (3D-CRT) (n=576) or intensity-modulated RT (IMRT) (n=497). The patients were divided into two groups treated at high volume institution (HVI) (n=750) and low volume institution (LVI) (n=323), defined as patient volume ≥ 10 (median, 13; range, 10 to 18) and < 10 patients per year (median, 3; range, 2 to 6), respectively. Endpoints were overall survival (OS) and loco-regional progression-free survival (LRPFS). At a median follow-up of 56.7 months, the outcomes were significantly better in those treated at HVI than at LVI. For the 614 patients of propensity score-matched cohort, 5-year OS and LRPFS were consistently higher in the HVI group than in the LVI group (OS: 78.4% vs. 62.7%, p < 0.001; LRPFS: 86.2% vs. 65.8%, p < 0.001, respectively). According to RT modality, significant difference in 5-year OS was observed in patients receiving 3D-CRT (78.7% for HVI vs. 58.9% for LVI, p < 0.001) and not in those receiving IMRT (77.3% for HVI vs. 75.5% for LVI, p=0.170). A significant relationship was observed between HVI and LVI for the clinical outcomes of patients with NPC. However, the difference in outcome becomes insignificant in the IMRT era, probably due to the standardization of practice by education.