[A case of mediastinal lymph node metastasis from rectal cancer successfully treated by carbon ion radiotherapy].

We report a case of mediastinal lymph node metastasis from rectal cancer successfully treated by carbon ion radiotherapy. A 65-year-old woman underwent sigmoid colostomy against unresectable rectal cancer. After chemoradiotherapy, primary rectal cancer became resectable and low anterior resection was performed. Curative local resection was done and chemoradiotherapeutic effect was grade 2. Chemotherapy after the operation wasn't effective enough and the size of the mediastinal lymph node increased. So she underwent carbon ion radiotherapy (52.8 Gy) which markedly decreased the lymph node size (-48%). Multi-modality therapy, such as radiation, chemotherapy, operation and carbon ion radiotherapy was applied. Successfully, locally advanced rectal cancer was resected and distant lymph node metastasis was controllable.