Intensity-modulated radiation therapy for anal malignancies: a preliminary toxicity and disease outcomes analysis.
OBJECTIVE
Intensity-modulated radiation therapy (IMRT) has the potential to reduce toxicities associated with chemoradiotherapy in the treatment of anal cancer. This study reports the results of using IMRT in the treatment of anal cancer.


METHODS
Records of patients with anal malignancies treated with IMRT at Duke University were reviewed. Acute toxicity was graded using the NCI CTCAEv3.0 scale. Overall survival (OS), metastasis-free survival (MFS), local-regional control (LRC) and colostomy-free survival (CFS) were calculated using the Kaplan-Meier method.


RESULTS
Forty-seven patients with anal malignancy (89% canal, 11% perianal skin) were treated with IMRT between August 2006 and September 2008. Median follow-up was 14 months (19 months for SCC patients). Median radiation dose was 54 Gy. Eight patients (18%) required treatment breaks lasting a median of 5 days (range, 2-7 days). Toxicity rates were as follows: Grade 4: leukopenia (7%), thrombocytopenia (2%); Grade 3: leukopenia (18%), diarrhea (9%), and anemia (4%); Grade 2: skin (93%), diarrhea (24%), and leukopenia (24%). The 2-year actuarial overall OS, MFS, LRC, and CFS rates were 85%, 78%, 90% and 82%, respectively. For SCC patients, the 2-year OS, MFS, LRC, and CFS rates were 100%, 100%, 95%, and 91%, respectively.


CONCLUSIONS
IMRT-based chemoradiotherapy for anal cancer results in significant reductions in normal tissue dose and acute toxicities versus historic controls treated without IMRT, leading to reduced rates of toxicity-related treatment interruption. Early disease-related outcomes seem encouraging. IMRT is emerging as a standard therapy for anal cancer.
Pepek
Joseph M
JM
Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27710, USA.
Willett
Christopher G
CG
Wu
Q Jackie
QJ
Yoo
Sua
S
Clough
Robert W
RW
Czito
Brian G
BG
D000230:Adenocarcinoma / Q000532:radiotherapy; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000209:etiology; D001005:Anus Neoplasms / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy; D003967:Diarrhea / Q000209:etiology; D005260:Female; D006801:Humans; D007970:Leukopenia / Q000209:etiology; D008297:Male; D008545:Melanoma / Q000532:radiotherapy; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000532:radiotherapy; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D012208:Rhabdomyosarcoma / Q000532:radiotherapy; D012509:Sarcoma / Q000532:radiotherapy; D013921:Thrombocytopenia / Q000209:etiology; D016896:Treatment Outcome; D055815:Young Adult