Coexistence of malignant struma ovariiwith abdominal wall metastasis and cervical papillary thyroidcarcinoma with RET/PTC۱ rearrangement

Introduction: Struma ovarii is a mature cystic teratoma composedpredominantly or entirely of thyroid tissue (≥۵۰%).Struma ovarii is a rare medical condition, and malignant transformationis even rarer. The coexistence of malignant strumaovarii and cervical thyroid carcinoma is also scarce, with datainsufficiency in molecular analysis. Here, we described the firstreport of coexistent malignant struma ovarii with abdominalwall metastasis and cervical papillary thyroid carcinoma withRET/PTC۱ rearrangement.Methods: A ۴۷-year-old multigravida woman with abnormaluterine bleeding was referred, and the evaluations revealedbilateral adnexal and lower abdominal wall masses. Then, ahysterectomy, bilateral salpingo-oophorectomy, and surgicalremoval of the abdominal wall mass were performed. Furthermore,a nodule within the left lobe of the cervical thyroid glandwas located during examination and ultrasound. Consequently,the patient underwent a total thyroidectomy. Finally, samplesof all affected tissue, including adnexal and abdominal wallmasses and cervical thyroid gland, were examined for BRAFV۶۰۰E, N-RAS, and RET/PTC۱ rearrangement. Then, the patientwas followed for six years after receiving radioactive iodineablation.Results: In histopathological evaluations, papillary thyroid carcinoma(PTC) was found within struma ovarii, and metastaticPTC was located in the abdominal wall fibro adipose tissue.Moreover, the cervical thyroid gland pathological examinationillustrated bilateral and multifocal PTC. Furthermore, RET/PTC۱ rearrangement was detected in the PTC arising in strumaovarii, abdominal wall metastasis, and cervical thyroid gland.Finally, six years of follow-up showed no evidence of recurrenceor distant metastasis.Conclusion: In light of these findings, considering suspectedcervical thyroid carcinoma while diagnosing malignant strumaovarii might be beneficial. In addition, according to the rarityof concurrent development of malignant struma ovarii andcervical thyroid carcinoma, the molecular investigation couldyield valuable results to explain the underlying mechanism ofcoexisting conditions, the tumor’s malignant behavior, and thepatient’s prognosis.

کلیدواژه ها:

malignant struma ovarii ، papillary thyroid carcinoma ، cervical thyroid carcinoma ، molecular diagnostic ، RETrearrangement