Radioactive iodine treatment of papillary thyroid carcinoma in Japan

Abstract

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.

Clinical and prognosis value of the number of metastatic lymph nodes in patients with papillary thyroid carcinoma

“…We suggested that pN1b patients with total thyroidectomy should accept a subsequent RAI treatment, which completely remove tumor and residual thyroid tissue to prevent the recurrence and distant metastasis by promoting sufficient I 131 to enter the residual thyroid tissue and metastatic focus [ 36 , 37 ]. However, RAI should only be employed in patients with a total thyroidectomy because I 131 can damage normal thyroid tissue [ 13 ]. It may be necessary to evaluate NMLNs and estimate the effect of RAI treatment in the future.…”

“…The current study aimed to evaluate the clinical and prognosis significance of NMLNs ≥ 5 among pN1 patients. It was noted that there were great differences in cervical LNM of patients with PTC and the surgical treatment of LNs for patients with PTC among different hospitals is still different and depends on the judgment of surgeon on the procedural safety [ 6 , 12 , 13 , 21 ].…”

“…In addition, several studies have also reported that LNM is a reliable predictor for recurrence [ 9 , 10 ] and poor prognosis of PTC [ 7 , 11 ]. However, there are guidelines on the management of PTC proposing different opinions on the management of central cervical lymph nodes (LNs) in different countries and regions [ 1 , 12 , 13 ].…”

Long-term management of recurrent papillary thyroid carcinoma treated with lenvatinib for over 5 years: a case report

“…This may not be a standard treatment, globally, but is a common practice in many cities in Japan. High-dose RAI therapy is not performed for many patients with recurrent differentiated thyroid cancer in Japan due to the very limited number of facilities available for high-dose RAI therapy since the use of radiation is unpopular for historical reasons [ 17 , 18 ]. Furthermore, there was a report that the diagnostic RAI scintigraphy using small amounts of RAI can predict the efficacy of high-dose RAI therapy [ 19 ].…”

Long-term treatments results for papillary thyroid carcinoma at a single general hospital

“…9 One of these is the ATA guidelines, and similar risk factors have also been proposed in Japan. 3,5 Although the risk slightly differs depending on the treatment of 1-2 cm tumors and metastatic lymph nodes, these evaluations are based on the TNM classi cation.…”