Simultaneous integrated boost intensity-modulated radiotherapy versus 3-dimensional conformal radiotherapy in preoperative concurrent chemoradiotherapy for locally advanced rectal cancer.
- Author:
Bong Kyung BAE
1
;
Min Kyu KANG
;
Jae Chul KIM
;
Mi Young KIM
;
Gyu Seog CHOI
;
Jong Gwang KIM
;
Byung Woog KANG
;
Hye Jin KIM
;
Soo Yeun PARK
Author Information
- Publication Type:Original Article
- Keywords: Rectal neoplasms; Intensity-modulated radiotherapy; Conformal radiotherapy; Chemoradiotherapy; Neoadjuvant therapy
- MeSH: Capecitabine; Chemoradiotherapy*; Drug Therapy; Fluorouracil; Humans; Leucovorin; Neoadjuvant Therapy; Radiotherapy, Conformal*; Radiotherapy, Intensity-Modulated*; Rectal Neoplasms*; Retrospective Studies; Skin
- From:Radiation Oncology Journal 2017;35(3):208-216
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: To evaluate the feasibility of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for preoperative concurrent chemoradiotherapy (PCRT) in locally advanced rectal cancer (LARC), by comparing with 3-dimensional conformal radiotherapy (3D-CRT). MATERIALS AND METHODS: Patients who were treated with PCRT for LARC from 2015 January to 2016 December were retrospectively enrolled. Total doses of 45 Gy to 50.4 Gy with 3D-CRT or SIB-IMRT were administered concomitantly with 5-fluorouracil plus leucovorin or capecitabine. Surgery was performed 8 weeks after PCRT. Between PCRT and surgery, one cycle of additional chemotherapy was administered. Pathologic tumor responses were compared between SIB-IMRT and 3D-CRT groups. Acute gastrointestinal, genitourinary, hematologic, and skin toxicities were compared between the two groups based on the RTOG toxicity criteria. RESULTS: SIB-IMRT was used in 53 patients, and 3D-CRT in 41 patients. After PCRT, no significant differences were noted in tumor responses, pathologic complete response (9% vs. 7%; p = 1.000), pathologic tumor regression Grade 3 or higher (85% vs. 71%; p = 0.096), and R0 resection (87% vs. 85%; p = 0.843). Grade 2 genitourinary toxicities were significantly lesser in the SIB-IMRT group (8% vs. 24%; p = 0.023), but gastrointestinal toxicities were not different across the two groups. CONCLUSION: SIB-IMRT showed lower GU toxicity and similar tumor responses when compared with 3D-CRT in PCRT for LARC.