title: Retrospective analysis of 5037 patients with nasopharyngeal carcinoma treated during 1976-1985: overall survival and patterns of failure.
abstract: This is a retrospective analysis of 5037 patients with squamous cell carcinoma of the nasopharynx treated during the years 1976-1985. The stage distribution according to Ho's classification was 9% Stage I, 13% II, 50% III, 22% IV, and 6% Stage V. Only 4488 (89%) patients had a full course of megavoltage radiation therapy. The median equivalent dose to the nasopharyngeal region was 65 Gy and cervical region in node-positive patients 53 Gy. Seventy percent (906/1290) of the node-negative patients had no prophylactic neck irradiation. The overall actuarial 10-year survival rate was 43%, and the corresponding failure-free survival 34%. Altogether, 4157 (83%) patients achieved complete remission lasting more than 6 months, but 53% (2205/4157) of them relapsed after a median interval of 1.4 years. The 10-year actuarial local, regional, and distant failure-free rates were 61%, 64%, and 59%, respectively. Thirty-eight percent (338/891) of all patients with local recurrence achieved second local remission. The local complete remission rate with aggressive re-irradiation alone was 47% (333/706). But 37% (124/338) of the responders recurred the second time. The incidence of distant failure correlated significantly with both the N-stage and the T-stage, with the highest (57%) occurring in patients with N3 disease. The incidence of nodal relapse in node-negative patients was 11% (44/384) among those given prophylactic neck irradiation, but 40% (362/906) among those without. Therapeutic irradiation achieved a complete regional remission rate of 90% (306/339). However, despite successful salvage, these patients had a significantly higher distant failure rate than those without nodal relapse, even if they remained local-failure-free (21% vs 6%). Patients treated during 1981-1985 achieved significantly better treatment results than those treated during 1976-1980, especially in terms of the overall survival (57% vs 47% at 5-year), the overall failure-free survival (42% vs 35% at 5-year), and the local failure-free rate (70% vs 63% at 5-year). The possible contributing factors are discussed.
authors.affiliation: Institute of Radiology and Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong.
authors.forename: A W
authors.initials: AW
authors.lastname: Lee
authors.forename: Y F
authors.initials: YF
authors.lastname: Poon
authors.forename: W
authors.initials: W
authors.lastname: Foo
authors.forename: S C
authors.initials: SC
authors.lastname: Law
authors.forename: F K
authors.initials: FK
authors.lastname: Cheung
authors.forename: D K
authors.initials: DK
authors.lastname: Chan
authors.forename: S Y
authors.initials: SY
authors.lastname: Tung
authors.forename: M
authors.initials: M
authors.lastname: Thaw
authors.forename: J H
authors.initials: JH
authors.lastname: Ho
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000401:mortality / Q000532:radiotherapy*; D002648:Child; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology / Q000401:mortality / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D012189:Retrospective Studies; D016019:Survival Analysis; D015996:Survival Rate