Radioactive iodine treatment of papillary thyroid carcinoma in Japan.

We have a unique history of using radioactive iodine (RAI) therapy and surgical treatment for thyroid cancer in Japan. Less than total thyroidectomy without RAI therapy was the most common management of papillary thyroid carcinoma (PTC) in the past. Limited availability of dedicated facilities for the RAI administration due to the strict regulations and insufficient coverage of the expenses were the major reasons that impacted on the management decisions. Following the publication of the Japanese clinical practice guidelines for thyroid tumors in 2010, the risk-adapted approach has become a standard where the high-risk and selected intermediate-risk PTC patients undergo total thyroidectomy followed by RAI therapy and thyrotropin suppression therapy. We are on the shoulders of pioneers who made every effort to bring the interventions closer to an ideal environment for patients. Armed with the revised clinical practice guidelines 2018 and devised inpatient/outpatient RAI therapy, Japanese physicians are ready to proceed to more rational management that would improve patients' outcomes. Directions for the future include further advancement of relevant clinical research to fill the gaps between current evidence and recommendations in the guidelines, and obtaining approval for high-dose RAI therapy on an outpatient basis to improve its effectiveness in both adjuvant and treatment settings.