JCOG Radiation Therapy Study Group: history and achievements.

The Radiation Therapy Study Group (RTSG) of the Japan Clinical Oncology Group (JCOG) was established in 2003. The missions of this group are to develop new standards of care with innovative, advanced technology radiation therapy, both for single- and multi-modality cancer treatment, and to improve radiation therapy quality and outcomes of JCOG trials conducted by other organ-oriented groups. In 2004, the first RTSG trial, a Phase II study of stereotactic body radiation therapy for Stage IA non-small cell lung cancer (JCOG 0403), was initiated. Four other trials are currently open for accrual. JCOG 0702 is a Phase I study of stereotactic body radiation therapy in patients with T2N0M0 non-small cell lung cancer. JCOG 0701 is a Phase III study comparing accelerated fractionation with conventional fractionation radiation therapy for T1-2N0M0 glottic cancer. JCOG 0906 is a multicenter safety trial of hypofractionated radiation therapy after breast-conserving surgery in patients with margin-negative invasive breast cancer. JCOG 1015 is a Phase II study of intensity-modulated radiation therapy with chemotherapy for loco-regionally advanced nasopharyngeal cancer. Other RTSG activities include a medical physics working group responsible for dosimetry audits; a genetic analysis working group involved in accompanying research to analyze single-nucleotide polymorphisms to identify predictors of radiation toxicities; a working group that has developed atlases of clinical target volumes for uterine cervical cancer; and participation in the Harmonisation Group to promote global harmonization of radiotherapy and radiotherapy quality assurance among trial groups. Further efforts to improve radiation therapy quality and outcomes of cancer treatment are necessary.