Effect of tumor bulk on local control and survival of patients with T1 glottic cancer: a 30-year experience.
OBJECTIVE
To evaluate the effect of tumor bulk on local control and survival of patients with T1 glottic cancer.


METHODS
Effects of tumor bulk, T-stage, anterior-commissure involvement, treatment duration, and fraction size were analyzed in 208 patients; 136 had small tumors and 72 had bulky tumors. Anterior-commissure was involved in 54 patients. Treatment duration ranged from 39 to 64 days and fraction size ranged from 1.8 to 2.0 Gy. Median follow-up was 5.1 years.


RESULTS
Five-year actuarial local control rates were 86.1% and 91.4% after radiotherapy and salvage laryngectomy. On univariate analysis, local control rates were 92.6% and 73.6% for small and bulky tumors (p = 0.03), 89.6% and 75.9% for patients without and with anterior-commissure involvement (p = 0.01), 92.6% and 75.6% when treatment duration was <or=50 days and >50 days (p = 0.04), and 90.2% and 76.4% with 2 Gy and 1.8 Gy (p = 0.02) per fraction. On multivariate analysis, tumor bulk was the only significant factor that affected local control (p = 0.007). Ultimate local control rates after salvage were 97.1% and 80.5% for patients with small and bulky tumors. Disease-free survival rates at 5 years for small and bulky tumors were 96.3% and 84.7% (p = 0.001). Median duration to recurrence for small tumors was 30 months as compared with 11 months for bulky tumors.


CONCLUSIONS
Tumor bulk is a highly significant prognostic factor for radiation control of T1 glottic cancer. Patients with bulky tumors had lower local control and disease-free survival rates and shorter duration to recurrence than those with small tumors.
Reddy
Sarada P
SP
Loyola-Hines Department of Radiotherapy, Loyola University Chicago, Maywood, IL 60153, USA. sreddy1@lumc.edu
Hong
Robert L
RL
Nagda
Suneel
S
Emami
Bahman
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D005931:Glottis; D006801:Humans; D007822:Laryngeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D007825:Laryngectomy; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011879:Radiotherapy Dosage; D016879:Salvage Therapy; D015996:Survival Rate; D013997:Time Factors; D047368:Tumor Burden; D014833:Voice Quality