The Lung Cancer Surgical Study Group of the Japan Clinical Oncology Group: past activities, current status and future direction.

The Lung Cancer Surgical Study Group of the Japan Clinical Oncology Group was organized in 1986. Initially, 26 collaborative institutions participated. In the early period, the Lung Cancer Surgical Study Group focused on combined modality therapies and conducted nine trials, including JCOG9101: adjuvant chemotherapy for resected small-cell lung cancer, and JCOG9806: induction chemoradiotherapy followed by surgery for superior sulcus tumor, which greatly impacted the treatment strategies for some special kinds of lung cancer. Since the 2000s, the Lung Cancer Surgical Study Group has defined radiologically noninvasive adenocarcinoma: JCOG0201 and investigated adequate modes of surgical resection for small-sized non-small cell lung cancer: JCOG0802, JCOG0804 and JCOG1211. The accrual of these trials is now complete and we are waiting for the maturation of follow-up data. In addition, two adjuvant trials have been conducted: JCOG0707; a Phase III study of adjuvant chemotherapy for resected pathological stage I (T1 > 2 cm) non-small cell lung cancer, and JCOG1205; a Phase III study of adjuvant chemotherapy for completely resected pulmonary high-grade neuroendocrine tumor. The accrual of JCOG0707 is complete and we are waiting for the maturation of follow-up data. At present, 44 institutions are active members of the Lung Cancer Surgical Study Group. In addition to thoracic surgeons, medical oncologists, pathologists and radiotherapists are participating in the Lung Cancer Surgical Study Group. The Lung Cancer Surgical Study Group continues to conduct various clinical trials in an effort to improve survival in patients with lung cancer. In this review, we provide an overview of the past 30 years, as well as the present status and future direction of the Lung Cancer Surgical Study Group.