Papillary Thyroid Cancer in a Struma Ovarii in a 17-Year-Old Nulliparous Patient: A Case Report

Abstract

Introduction: Struma ovarii accounts for 2% of mature teratomas. Struma ovarii is diagnosed when thyroid tissue accounts for >50% of the teratoma. Malignant transformation is rare, occurring in <5% of struma ovarii cases. Case presentation: A 17-year-old patient was diagnosed with papillary thyroid cancer in struma ovarii. The patient exhibited menstrual disorders. Abdominal and pelvic CT revealed a 17 cm mass in the left adnexa. Laparoscopic removal of the left adnexa with enucleation of right ovarian cysts was performed. Histopathological diagnosis was a follicular variant papillary carcinoma measuring 23 mm in diameter. Immunohistochemical positive expression of CK19, TTF-1, and thyroglobulin (Tg) confirmed the diagnosis. Molecular analysis detected the BRAF K601E mutation in ovarian tumor tissues. Preoperative serum Tg concentration was >300 ng/mL, which decreased to 38.2 ng/mL after gynecological surgery with undetectable anti-Tg antibodies. The patient underwent total thyroidectomy with no cancer detected on histopathological examination. The patient was treated with I-131 and showed no recurrence 4 years after the diagnosis. Conclusions: Malignant struma ovarii is diagnosed by surgery. Because papillary carcinoma in struma ovarii is rare and there are no guidelines regarding the management of this type of cancer, therapeutic decisions should be made individually based on clinical and pathological data.

Recurrent Struma Ovarii Presented with High Levels of Thyroglobulin

“…A similar approach is as well recommended even when there is a high index of suspicion for malignancy, mainly due to the low metastatic potential of the tumor and low risk of recurrence. In contrast, total hysterectomy with bilateral salpingo-oophorectomy or/and omentectomy can be a reasonable choice for postmenopausal women or those without maternity plans [ 11 ]. Metastatic disease in the abdominal cavity has been rarely reported in the fallopian tubes, the contralateral ovary, the para-aortic lymph nodes, the greater omentum, and pelvic walls [ 12 ].…”

Malignant struma ovarii with papillary carcinoma combined with retroperitoneal lymph node metastasis: A case report

“…The malignant transformation rate is as low as 5%, and the most common malignancies are papillary carcinoma (approximately 70%) and follicular carcinoma (approximately 30%)[ 4 , 6 , 10 - 11 ]. MSO metastasizes in approximately 5%-23% of cases[ 2 , 10 ], mainly leading to lymphatic and blood metastasis and peritoneal and omental metastasis, but metastases have also been seen in the pelvis, liver, lung, etc. [ 1 , 2 ].…”

“…It can occur in women of any age. However, this tumor is more common in women aged 4-60 years and is less common in postmenopausal women[ 10 ]. The clinical manifestations of the disease are nonspecific and usually include abdominal symptoms, such as abdominal pain, abdominal distention, abdominal mass, irregular vaginal bleeding, and infertility.…”

“…The management course of abdominal hysterectomy and bilateral salpingo-oophorectomy with omentectomy, with or without hysterectomy, and unilateral adnexal resection is supported by most scholars only for young patients without metastases to preserve fertility to the greatest extent possible. Extraovarian tumor extension is considered an indication for total thyroidectomy and adjuvant treatment, such as radioactive iodine [I]-131 ablation, in postoperative patients[ 6 , 10 , 12 , 13 ]. The greatest controversy has been whether to routinely administer postoperative adjuvant therapy to patients without evidence of metastasis.…”

“…This tumor is usually benign, and malignant transformation and metastasis are extremely rare, with malignant transformation occurring in approximately 5% of cases[ 4 , 6 ]. The disease can affect females of all ages but is most common in patients of childbearing age[ 10 ]. The clinical manifestations of this disease are not specific and are mostly characterized by abdominal symptoms, such as abdominal pain and irregular vaginal bleeding[ 4 ].…”