Acute and late complications after hypofractionated intensity modulated radiotherapy in prostate cancer.

The present study compared the complications associated with hypofractionated intensity-modulated radiation therapy (Hypo-IMRT) of prostate cancer to conventionally fractionated IMRT (Conv-IMRT).

Hypo-IMRT delivered 70 Gy in 28 fractions, whereas Conv-IMRT delivered 78 Gy in 39 fractions. Toxicity was graded with the Common Terminology Criteria for Adverse Events, version 4.0, weekly during radiotherapy, 1 month after radiotherapy, and annually in both patient groups.

The median follow-ups were 39.1 and 38.7 months for patients in the Hypo- and Conv-IMRT groups, respectively. There was no significant difference in rates of acute and late adverse events. The proportions of grade 2 acute genitourinary complications were 48.4 and 51.2% in the Hypo- and Conv-IMRT groups, respectively. The presence of a baseline International Prostate Symptom Score (IPSS) of ten or more was the only significant prognostic factor for grade 2 acute genitourinary toxicity. The incidence of grade 2 late rectal hemorrhage at 3 years was 3.2 and 3.5% in the Hypo- and Conv-IMRT groups, respectively. Small rectal volume was significantly associated with grade 2 late rectal hemorrhage.

Regarding acute and late adverse events, hypofractionated IMRT for prostate cancer was well tolerated and comparable with conventionally fractionated IMRT. Clinical trial registration no. UMIN000003218.

Japanese journal of radiology. 2017 Mar 09 [Epub]

Takuyo Kozuka, Masahiro Nakano, Masatoshi Hashimoto, Kotaro Gomi, Keiko Nemoto Murofushi, Minako Sumi, Junji Yonese, Masahiko Oguchi

Department of Radiation Oncology, Cancer Institute Hospital of the Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan. ., Department of Physics, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan., Department of Radiation Oncology, Japanese Red Cross Society Suwa Hospital, Nagano, Japan., Department of Radiation Oncology, Cancer Institute Hospital of the Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan., Department of Urology, Cancer Institute Hospital of the Japanese Foundation for Cancer Research, Tokyo, Japan.