Supplementary Material for: Two Cases of Malignant Struma Ovarii with Metastasis to Pelvic Bone

Histologically, malignant struma ovarii metastasizes rarely, and only a few cases reported bone metastasis. Here, we describe 2 cases of biologically malignant struma ovarii with pelvic bone metastasis. Case 1 is a 22-year-old female who was found to have a large left ovarian mass during routine prenatal ultrasound. Papillary thyroid cancer arising in struma ovarii was identified after laparoscopic salpingo-oophorectomy. After total thyroidectomy, radioactive iodine whole-body scan revealed extrathyroidal iodine uptake in left anterior pelvis. Subsequent I-131 treatment resolved the pelvic metastasis. Case 2 is a 49-year-old female who was diagnosed with malignant struma ovarii in 1996 and presented in 2007 with pelvic recurrence and extensive left hip metastasis. Treatment with resection of the pelvic tumor, total thyroidectomy, and multiple I-131 ablation led to eventual resolution of the abdominal and left hip foci. In conclusion, we present 2 rare cases of malignant struma ovarii, both with metastasis to the pelvic bone. This report makes pelvic bone the most frequent site for bone metastasis in malignant struma ovarii. It also emphasizes the importance of total thyroidectomy in allowing identification and treatment of bony metastasis with radioactive iodine.

组织病理学上，恶性卵巢甲状腺肿（malignant struma ovarii）极少发生转移，目前仅见少量骨转移病例报道。本文报告2例伴骨盆骨转移的生物学行为恶性卵巢甲状腺肿病例。
病例1为22岁女性，于常规产前超声检查中发现左侧卵巢巨大肿物。患者接受腹腔镜输卵管卵巢切除术（laparoscopic salpingo-oophorectomy）后，病理证实为卵巢甲状腺肿恶变伴甲状腺乳头状癌（papillary thyroid cancer）。行全甲状腺切除术（total thyroidectomy）后，放射性碘（radioactive iodine）全身显像显示左前盆腔存在甲状腺外碘摄取灶。后续予以¹³¹碘治疗后，盆腔转移灶完全消退。
病例2为49岁女性，1996年确诊恶性卵巢甲状腺肿，2007年因盆腔复发伴广泛左侧髋部转移就诊。予盆腔肿瘤切除术、全甲状腺切除术及多次¹³¹碘消融治疗后，腹腔及左侧髋部转移灶最终完全消退。
综上，本文报告2例罕见的恶性卵巢甲状腺肿病例，均发生骨盆骨转移。本研究提示骨盆为恶性卵巢甲状腺肿骨转移的最常见部位，同时强调全甲状腺切除术有助于明确诊断，并可通过放射性碘治疗实现骨转移灶的有效控制。