Conformal therapy improves the therapeutic index of patients with anal canal cancer treated with combined chemotherapy and external beam radiotherapy.
OBJECTIVE
To evaluate the clinical outcomes of three-dimensional conformal radiotherapy (3D-CRT) in patients with anal canal cancer, in terms of local control (LC), freedom from relapse (FFR), and overall survival (OS) rates, and to estimate long-term toxicity data.


METHODS
Sixty historical patients, treated with conventional radiation techniques (C-RT), were used as controls, and 62 consecutive patients were treated with 3D-CRT. Patients treated with 3D-CRT received 54 Gy in 30 fractions delivered continuously, compared with 45-58.9 Gy (median dose, 54 Gy) in a split course in patients treated with C-RT. Chemotherapy consisted of 5-fluorouracil with either mitomycin-C or cis-platinum given concurrently with radiation. Survival curves were performed using the Kaplan-Meier model, and the Cox proportional hazards model was used for multivariate analysis of risk factors.


RESULTS
No differences in stage and age distribution were observed between the two groups. Patients treated with 3D-CRT and C-RT had an actuarial 5-year LC rate of 85.1% and 61.1%, respectively (p = 0.0056); the FFR rate was 70.2% and 46.1% (p = 0.0166), and the OS rate was 80.7% and 53.9% (p = 0.0171). In multivariate analysis, factors of significance for LC were nodal (N) status (p < 0.001); for OS, 3D-CRT (p = 0.038), N status (p = 0.011), and T status (p = 0.012); and for FFR, 3D-CRT (p = 0.024) and N status (p < 0.001).


CONCLUSIONS
The use of 3D-CRT allows patients with anal canal cancer to complete radiation and chemotherapy without interruption for toxicity, with significant improvements in LC, FFR, and OS.
Vuong
Té
T
Department of Radiation Oncology, McGill University Health Centre, Quebec, Canada. te.vuong@muhc.mcgill.ca
Kopek
Neil
N
Ducruet
Thierry
T
Portelance
Lorraine
L
Faria
Sergio
S
Bahoric
Boris
B
Devic
Slobodan
S
D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D001005:Anus Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000532:radiotherapy*; D002945:Cisplatin / Q000008:administration & dosage; D003131:Combined Modality Therapy / Q000379:methods; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000009:adverse effects; D016019:Survival Analysis
D016685:Mitomycin; D002945:Cisplatin; D005472:Fluorouracil