Struma ovarii and hyperthyroidism.

Thyroid tissue is a relatively frequent component of mature teratoma and can occur in 5-20 % of cases. Struma ovarii is defined as ovarian goiter which comprises either entirely or predominantly thyroid tissue (>50 %). This also includes cases of mature teratoma with less than 50 % thyroid tissue but harboring thyroid-associated malignancy. A total of 118 patients with mature teratoma containing thyroid tissue were identified at our institution (1989 to 2014). Ninety-six cases were diagnosed struma ovarii, including 10 cases of papillary thyroid carcinoma, 1 case of highly differentiated follicular carcinoma of ovarian origin (HDFCO), 5 cases of strumal carcinoid, and 80 cases of struma ovarii (53 cases of thyroid-only struma ovarii). Six cases had diffuse adenomatous hyperplasia, and seven cases had focal adenomatous hyperplasia. There was no recurrence on follow-up except one of the papillary thyroid carcinomas. Concurrent primary ovarian lesions included: serous cystadenoma--3, mucinous cystadenoma--4, Brenner tumor--3, thecoma--2, ovarian fibroma--1, and focal hilus cell hyperplasia--4 cases. In this series, papillary thyroid carcinoma and strumal carcinoid were the most common well-differentiated neoplasm/malignancies arising in struma ovarii; these demonstrate a minimal or no aggressive clinical behavior.

Malignant Struma Ovarii: An Autopsy Report of a Clinically Unsuspected Tumor

Ectopic thyroid tissue is a rare entity and when discovered it is typically along the pathway of embryologic migration of the thyroid. We present a case of incidental finding of ectopic thyroid tissue within mediastinum in a 61-year-old female patient with a history of total thyroidectomy for thyroiditis and nodules. The patient presented to emergency room with cough and right chest pain and underwent a chest computed tomographic angiogram (CTA) to exclude pulmonary embolism as part of chest pain workup. One right paratracheal mediastinal soft tissue nodule was visualized on the images of CTA. This right paratracheal soft tissue mass was found to be ectopic benign thyroid tissue by histological analysis of the biopsied tissue samples. The function of this ectopic thyroid tissue was characterized by I-123 radioiodine uptake and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. This case illustrates that ectopic thyroid tissue should be included for differential diagnosis of a hyperdense soft tissue mass located within mediastinum. I-123 SPECT/CT is useful for guiding tissue biopsy of ectopic thyroid tissue distant from orthotopic thyroid gland and functional and anatomic characterization of mediastinal ectopic thyroid tissue for surgical resection when it is medically necessary.

Ectopic thyroid is a condition in which the thyroid tissue is present outside its normal anatomical position. Usually the ectopic thyroid is present along the line of its migration. The presence of ectopic thyroid tissue within the trachea is a very rare condition. Surgery is appropriate treatment for patients with ectopic thyroid tissue with clinical signs of upper airway obstruction. Here we present such a case where an ectopic intratracheal thyroid was causing airway obstruction.

Struma ovarii is an ovarian tumor, characterized by the presence of thyroid tissue comprising >50% of the overall mass. Although struma ovarii does not usually secrete thyroid hormones, there are cases in which it produces thyroid hormones, which results in hyperthyroidism. Here, we report the case of a 73-year-old female who presented with a right ovarian mass and symptoms suggestive of thyrotoxicosis. Her thyroid function test showed suppressed thyroid-stimulating hormone and elevated T3 and T4 levels. We suspected thyroiditis initially. Later, in view of persistent thyrotoxicosis, she was started on antithyroid drugs. Tc99 pertechnetate thyroid uptake scan showed absent uptake in the neck. A possibility of struma ovarii was considered. She underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Histopathology revealed >80% thyroid tissue suggestive of struma ovarii with a coexistent Brenner tumor. Postoperatively, her thyrotoxicosis got resolved. To conclude, in any case of thyrotoxicosis that is persisting and with absent uptake in the neck, rare cases such as struma ovarii should be considered. Struma ovarii with a coexistent Brenner tumor is a very rare finding.

Value of dynamic contrast-enhanced MRI for tissue characterization of ovarian teratomas: Correlation with histopathology

Background: Struma ovarii is a rare monodermal variant of ovarian teratoma, characterized by the presence of mature thyroid tissue comprising more than 50% of the Tumor. Struma ovarii is a rare ovarian tumor, accounting for 1% of all ovarian tumors and 2-5% of ovarian teratomas. It consists predominantly or entirely of thyroid tissue and can occasionally exhibit functional thyroid activity. Case Presentation: This case report discusses a 41-year-old female who presented with nonspecific abdominal discom- fort and a gradually enlarging pelvic mass. Pelvic ultrasonography revealed a complex, predominantly cystic ovarian mass. The patient underwent a laparoscopic salpingo-oophorectomy, and histopathological examination confirmed the diagnosis of struma ovarii. Thyroid function tests were within normal limits, and no evidence of malignancy or metastatic disease was observed. The patient’s postoperative course was uneventful, with complete resolution of symptoms. Struma ovarii can present diagnostic challenges due to its nonspecific clinical and radiological features, often mimicking other ovarian neoplasms. Although typically benign, it can occasionally undergo malignant transformation or cause thyrotoxi- cosis. This case emphasizes the importance of considering struma ovarii in the differential diagnosis of ovarian masses and highlights the role of histopathology in definitive diagnosis. Early recognition and appropriate surgical management are crucial for favorable outcomes in patients with this rare ovarian tumor. Conclusion: Struma ovarii is often asymptomatic or presents with nonspecific symptoms, making preoperative diagnosis challenging. Surgical excision remains the mainstay of treatment, with a favorable prognosis in most benign cases. CME J 2025; 4(1); 64-67

Struma Ovarii (SO) is a rare form of teratoma of ovary containing predominantly thyroid tissue, usually comprising more than 50% of the overall mass. It accounts for 1% of all ovarian tumours in adults. Due to its rare presentation in paediatric age group, the exact incidence is not known.The association of SO with hyperthyroidism has been noted in approximately 8% of cases. Radiological evaluation helps in preliminary diagnosis of a complex ovarian cyst, however, a definitive diagnosis of SO can only be made upon extensive histopathological evaluation. Present report is of SO in a 12-year-old female patient, who initially presented with pain abdomen, vomiting and hyperthyroidism with mildly elevated thyroid hormones Triiodothyronine (T3) and Tetraiodothyronine (T4). Magnetic Resonance Imaging (MRI) whole abdomen showed evidence of right-sided dermoid with mild ascites. An exploratory laparotomy was done followed by right ovarian cystectomy and histopathology revealed a mature teratoma predominantly comprising of thyroid tissue (>90% of total ovarian mass), thereby confirming the diagnosis of SO. After one month of surgical resection, the patient’s thyroid profile showed decrease in fT3 and fT4 levels. The index case highlights the unusual occurrence of SO in a paediatric patient along with the role of an extensive histopathological evaluation in diagnosis of the same.

IntroductionStruma ovarii is a subtype of mature teratoma characterized by the presence of predominantly thyroid tissue (>50%) [1]. This condition is usually benign, with malignant transformation occurring in only 0.5-5% of cases, requiring management similar to that of thyroid cancer. The most common malignancy found in struma ovarii, similar to the thyroid gland, is papillary thyroid carcinoma (PTC) [2]. Here, we report a case of a 73-year-old woman with papillary thyroid cancer in struma ovarii.Clinical CaseA 73-year-old female patient, who was admitted with abdominal pain, underwent bilateral salpingo-oophorectomy due to 4 and 5 cm lesions thought to be hemorrhagic cysts on her right and left ovaries. Pathology result revealed a 2.2 cm teratoma in the left ovary. In the sections, in addition to struma ovarii (>90%), areas of mature teratoma differentiated in the direction of the ectoderm were observed. Two papillary carcinoma foci of 1 cm and 0.5 cm in diameter were detected within the struma ovarii, but no lymphovascular invasion or capsular involvement was observed (Picture 1). In the right ovary, only areas of mature teratoma (struma ovarii) consisting of benign thyroid tissue were seen. Her comorbidities included Type 2 Diabetes Mellitus, Stage 3 Chronic Kidney Disease and Hepatitis B virus carriage. Thyroid ultrasonography result showed normal thyroid gland size and heterogeneous parenchyma with decreased echogenicity. PET/CT scan showed no pathological FDG uptake in the body in favor of malignancy. Laboratory results were given in Table 1. The patient was evaluated by the thyroid council; the stage was calculated as T1a(m)N0M0, AGES and MACIS scores were considered as low risk and a follow-up decision was made for the patient. Routine thyroid and neck ultrasonography along with abdominal and lung imaging were recommended. TSH level was planned to be maintained between 0.5-1 uU/mL and annual thyroglobulin follow-up was planned.ConclusionThe primary treatment for malignant struma ovarii is the surgical removal of the tumor. Additional therapies, such as thyroidectomy and radioiodine, may be required depending on the presence of metastatic disease and the risk of recurrence [2]. In cases with a low risk of recurrence, as in our patient (no extraovarian extension or distant metastases), most authors recommend levothyroxine to suppress TSH to the lower limit or slightly below normal, along with annual serum thyroglobulin monitoring. Severe elevations in thyroglobulin may indicate recurrence or metastatic disease. Long-term monitoring (at least 10 years) of serum thyroglobulin is necessary for patients with malignant struma ovarii. If the biochemical evidence of persistent or recurrent disease is found, appropriate imaging, including the pelvis, should be performed [3].Financial disclosures: NoneFunding resources: NoneFigure 1:Histological and radiological findings of the patient Table 1:Laboratory results

Background: Struma ovarii, an ovarian tumor, is diagnosed when >50% of the teratoma is thyroid tissue. Struma ovarii's incidence is <2% of mature teratoma. Case: We present a rare case report of struma ovarii of a 47-year-old female who presented with incomplete evacuation of bladder and bowel since 2 years. She also complained of dragging pain in abdomen, intermittent radiating to back since last 2/3 years. Her carcino embryonic antigen (CEA) level was 2.56 ng/mL and histologically proved to be struma ovarii. Results: Single cystic 7 × 4 cm left ovarian mass was diagnosed as struma ovarii. Conclusion: Struma ovarii though a rare entity should always be kept in mind in a pelvic mass lesion causing discomfort. It is not usually a malignant condition and histopathological examination should be done to rule out struma ovarii.

Malignant struma ovarii in an 11-year-old girl

A 44-year-old woman presented with left lower quadrant abdominal pain for 2 months. Further evaluation revealed a left adnexal mass and she underwent a TAH-BSO. A 12 cm mass arising from the left ovary was resected which on microscopy appeared to be papillary thyroid carcinoma follicular variant arising from a mature teratoma (struma ovarii). A thyroid ultrasound showed two subcentimeter right thyroid nodules without any concerning lymphadenopathy. A total thyroidectomy was then performed to allow her to receive adjuvant RAI. The cervical thyroid pathology showed a 0.6 cm follicular variant papillary thyroid carcinoma with negative margins without angioinvasion, lymphatic invasion or extrathyroidal extension. Thyroid hormone suppression with levothyroxine was started. Preoperatively, thyroglobulin was 1381 ng/ml (nl range 1.3-31.8 ng/ml). After TAH-BSO and thyroidectomy, thyroglobulin was undetectable and so was the anti-thyroglobulin antibody. With an undetectable thyroglobulin level, it was decided not to pursue adjuvant RAI and continue TSH suppression with levothyroxine. Simultaneous existence of malignant struma ovarii and cervical papillary thyroid cancer is rare and has a favorable prognosis compared to metastasis to the ovaries from primary cervical thyroid papillary carcinoma. Due to the rarity of this condition, management is not clear or well supported by evidence. Various approaches are suggested by different authors, including thyroidectomy after resection of malignant struma ovarii to facilitate adjuvant RAI, only performing surgical resection of the ovarian tumor in the absence of high risk features or performing thyroidectomy and RAI only in metastatic or recurrent disease.

Ectopic thyroid tissue (ETT) is a rare entity and a challenging differential diagnosis. This is a report of a case of a mediastinal mass that was found to be an ectopic mediastinal thyroid tissue, in a 77-year-old woman who was admitted to our hospital for breast cancer management. The mediastinal mass was identified in the postsurgical computed tomography (CT) scan of the chest and was suspected as mediastinal lymph node metastasis. A CT-guided percutaneous transthoracic punch biopsy (CT-TPB) proved to be an adequate diagnostic tool to exclude malignancy and provide a definite diagnosis of the mediastinal mass. We find that CT-guided punch biopsy as a useful diagnostic alternative enabling histopathological specimens to be obtained from mediastinal masses and lymph nodes suspected of malignancy.

Ectopic thyroid tissue is usually found in the midline along the path of descent of the thyroid gland, such as in the tongue, larynx, trachea, oesophagus, etc. Initially, laterally placed thyroid tissues were found to contain malignant tissue and hence the term lateral aberrant thyroid tumours. Some attributed these to metastatic deposits of primary thyroid carcinoma while others felt that these were primary tumours of aberrant thyroid tissue. In later years, benign ectopic thyroid tissues were described in the lateral neck. It was felt that ectopic thyroid tissues are derived from thyroid cell rests that have failed to fuse with the main thyroid tissue during development. They are subjected to the same goitrogenic stimulation as the normally placed thyroid tissue. Our case supports the view that not all laterally placed thyroid tissues are malignant and also presents an unusual subplatysmal location of ectopic thyroid tissue.

Subcutaneous ectopic thyroid tissue presenting as a midline neck mass in a middle-aged woman: a rare case report