Preliminary Observation of 3-D Conformal Radiation Therapy for Locally Recurrent Nasopharyngeal Carcinoma
10.3321/j.issn:1000-467X.2001.02.014
- VernacularTitle:局部复发鼻咽癌三维适形放疗初步观察
- Author:
Xiao-Kang ZHENG
1
;
Long-Hua CHEN
;
Jun MA
Author Information
1. Nanfang Hospital the First Military Medical University
- From:Chinese Journal of Cancer
2001;20(2):175-179
- CountryChina
- Language:Chinese
-
Abstract:
Objective: The current study was designed to investigate the retreatment of locally recurrent nasopharyngeal carcinoma (NPC) with three-dimensional conformal radiation therapy (3-D CRT). Methods: From April 1998 to October 1999, 26 patients with locally recurrent NPC (25 patients were poorly differentiated squamous cell carcinoma, 1 poorly differentiated adenoma) were retreated by 3-D CRT. The patients were restaged according to the Huaqing staging system with the following distribution: rT1N0M0 4, rT2N0M0 8, rT3N0M0 9, rT4N0M0 5. The maximal dimension of gross tumor volume (GTV) ranged from 1.0 cm to 5.0 cm (median: 3.1 cm). Among 5- 7 static conformal portals were delivered with coplanar or noncoplanar isocentric irradiation technique in this trial. The mean value of the maximal dose, the minimal dose and the average dose of the planning target volume (PTV) were 104.1± 1.3％ ,92.1± 2.8％ ,and 99.2± 1.7％ ， respectively. The prescription dose-fractionation-time was 65- 70 Gy/26- 28 F/5- 5.5 W. The median fellow-up time after 3-D CRT was 17 months(range:8- 26 months). Results:In the follow-up time,2 patients occurred marginal recurrence, 3 patients occurred regional failure, 2 patients occurred distant metastasis, and 4 patients died. No evidence of local failure was found in 88.5％ (23/26) of the patients, and 84.6％ (22/26) of the patients survived during the follow-up time. The acute and self-limiting complications from reirradiation were slight and few. The overall incidence of late radiation complications after reirradiation was 19.2％ (5/26). Functional impairment developed in 15.4％ (4/26) of the patients after reirradiation. Conclusion:3-D CRT,for locally recurrent NPC, had an obvious advantage on dose distribution. This preliminary result indicated that this new radiotherapy technique had a high local control rate and low complication rate. But its long term curative effect and sequelae need to be further observed.
