Radiotherapy for early glottic carcinoma (T1N0M0): results of prospective randomized study of radiation fraction size and overall treatment time.
OBJECTIVE
To investigate in a prospective randomized study the effect of radiation fraction size and overall treatment time on the local control of early glottic carcinoma.


METHODS
Between December 1993 and December 2001, 180 patients with early glottic carcinoma (T1N0M0) were treated at our department. The patients were randomly allocated to either treatment arm A (radiation fraction size 2 Gy, n = 89) or B (2.25 Gy, n = 91). The total radiation dose administered was 60 Gy in 30 fraction within 6 weeks for minimal tumors (two-thirds of the vocal cord or less) or 66 Gy in 33 fractions in 6.6 weeks for larger than minimal tumors (more than two-thirds of the vocal cord) in Arm A and 56.25 Gy in 25 fractions within 5 weeks for minimal tumor or 63 Gy in 28 fractions within 5.6 weeks for larger than minimal tumors in Arm B.


RESULTS
The 5-year local control rate was 77% for Arm A and 92% for Arm B (p = 0.004). The corresponding 5-year cause-specific survival rates were 97% and 100% (no significant difference). No significant differences were found between these two arms in terms of rates of acute mucosal reaction, skin reactions, or chronic adverse reactions.


CONCLUSIONS
Use of 2.25-Gy fractions with a shorter overall treatment time for Arm B showed superior local control compared with conventional use of 2-Gy fractions for Arm A without adverse reactions from the greater fraction.
Yamazaki
Hideya
H
Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Disease, Higashinari, Osaka-city, Osaka, Japan. hideya10@hotmail.com
Nishiyama
Kinji
K
Tanaka
Eiichi
E
Koizumi
Masahiko
M
Chatani
Masashi
M
D000368:Aged; D004812:Epidemiologic Methods; D005260:Female; D005931:Glottis; D006801:Humans; D007822:Laryngeal Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D007825:Laryngectomy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D016879:Salvage Therapy; D015996:Survival Rate; D013997:Time Factors