An active-surveillance clinical trial of low-risk papillary microcarcinoma (PMC) patients has been performed at the authors' institution, Kuma Hospital, since 1993. Favorable oncological results have been reported. During the trial, a few patients were encountered with PMC that showed enlargement during pregnancy, and these cases have been reported. During pregnancy, a large amount of human chorionic gonadotropin (hCG) having weak thyrotropin (TSH) activity is produced, possibly affecting the progression of PMC. This study investigated how pregnancy and delivery influenced the progression of PMC in the entire active surveillance PMC patient series.From 1993 to 2013, 1841 patients with low-risk PMC chose the active surveillance program. Fifty of the 1549 female PMC patients experienced 51 pregnancies/deliveries. To minimize observer variation, a single specialist sonographer re-evaluated the changes in the size of these 50 patients' PMCs before and after the pregnancies/deliveries.Four patients (8

作者：Yasuhiro, Ito；Akira, Miyauchi；Takumi, Kudo；Hisashi, Ota；Kana, Yoshioka；Hitomi, Oda；Hisanori, Sasai；Ayako, Nakayama；Tomonori, Yabuta；Hiroo, Masuoka；Mitsuhiro, Fukushima；Takuya, Higashiyama；Minoru, Kihara；Kaoru, Kobayashi；Akihiro, Miya

来源：Thyroid : official journal of the American Thyroid Association 2016 年 26卷 1期