Presentation and treatment of two cases of malignant struma ovarii.

BACKGROUND: Malignant Struma Ovarii (MSO) is a rare type of germ cell tumour which is diagnosed postoperatively on surgical pathology specimens by the presence of differentiated thyroid cancer in mature cystic teratomas in the ovaries. Treatment and follow-up procedures are not clearly established due to the paucity of MSO cases. CASE 1: A 44-year-old multiparous female presented with an irregular period. Ultrasound showed a left ovarian lesion mostly a dermoid cyst, however, CT showed a 3.8 × 2.7 × 4 cm complex cystic lesion with thick septation and enhancing soft tissue component. Laparoscopic left salpingo-oophorectomy was performed and histopathology showed a follicular variant of papillary thyroid carcinoma arising in a mature cystic teratoma. Peritoneal cytology was positive for malignancy. A thyroid function test was normal before surgery. Total thyroidectomy was performed followed by radioactive (RAI) iodine therapy. Later, a total laparoscopic hysterectomy and right salpingo-oophorectomy were performed. There is no evidence of recurrent disease during the 26-months follow-up. CASE 2: A 46-year-old single female presented with left lower abdominal pain that had persisted for 2 months. Imaging revealed an 8 × 9 × 9.5 cm left ovarian mass. Laparoscopic left salpingo-oophorectomy was performed and histopathology showed mature cystic teratoma with small papillary thyroid cancer. CT showed no evidence of metastatic disease. Later, the patient had a total thyroidectomy followed by radioactive (RAI) iodine therapy. She was started on thyroxine and later had total abdominal hysterectomy and right salpingo-oophorectomy. CONCLUSION: MSO is a very rare tumour. Preoperative diagnosis is very difficult because of the nonspecific symptoms and the lack of specific features in imaging studies. Also, there is no consensus on the optimal treatment of women with MSO. Our two cases add to the limited number of MSO cases.

A Curious Case of Omental Oxalate Crystals in a Patient With Struma Ovarii: Pointers to an Unusual Clinicopathological Scenario.

Percutaneous image-guided biopsies are becoming increasingly common in routine pathology practice, with the greater omentum emerging as a common target. We present herein an account of a middle-aged lady with a complex ovarian mass, omental thickening, and raised serum CA125; clinically suspected to have advanced ovarian malignancy. Fine needle aspiration cytology (FNAC) from the ovarian mass was inconclusive. Omental biopsy revealed only refractile, birefringent crystalline material with surrounding foreign body giant cell reaction; thus surprising the clinical team. Subsequent resection of the ovarian mass showed a teratoma composed exclusively of thyroid tissue, diagnosed as struma ovarii. The omental crystals, interpreted as calcium oxalate crystals, were possibly a consequence of colloid seeding during the ovarian mass FNAC.

Role of gene sequencing in classifying struma ovarii: BRAF p.G469A mutation and TERT promoter alterations favour malignant struma ovarii.

AIMS: Struma ovarii (SO) are rare, accounting for 0.3-1% of ovarian tumours, and include benign and malignant lesions. In most cases, histology is not predictive of clinical outcome and prognosis. The prognosis of histologically malignant thyroid-type carcinomas can indeed be excellent, while SO, composed of normal thyroid tissue, can recur and are designated highly differentiated follicular carcinoma of the ovary. Clearer diagnostic criteria are therefore required. METHODS AND RESULTS: We retrospectively studied 31 SO using DNA and RNA sequencing with pan-cancer gene panels, including eight biologically malignant SO (BMSO) defined based on ovarian serosal or extra-ovarian dissemination at presentation or during follow-up, 10 stage IA histologically malignant SO (HMSO) with thyroid-type carcinoma morphology and 13 biologically and histologically benign SO (BSO), with none of the above-mentioned characteristics. Molecular alterations were observed in 87.5% of BMSO, 70% of HMSO and 7.7% of BSO (P < 0.001). All patients with a peritoneal dissemination at presentation or during follow-up had at least one gene alteration. BRAF mutations (44.5%) were only observed in malignant forms (HMSO and BMSO) and TERT promoter alterations (25%) only in cases of BMSO. The BRAF p.G469A mutation, which is extremely rare in thyroid carcinomas, was the molecular alteration most frequently associated with malignant SO (28.5%). CONCLUSION: Our results highlight the clinical utility of molecular sequencing in SO, based on this limited number of cases. However, as malignant SO evolve slowly, more extensive molecular studies in SO with more than 10 years' follow-up are required to draw any conclusions on the prognostic value of the associated gene alterations.

Neoplasms in Struma Ovarii: A Review.

Struma ovarii is a well-known ovarian teratoma made up of benign thyroid tissue. These lesions demonstrate variable, normal architecture and normal thyroid immunohistochemical staining with positivity for TTF1, PAX8, and thyroglobulin. Though most are benign, some of these lesions can also present with a malignant component. Within this article, we review the most common diagnostic malignancies including papillary thyroid carcinoma, strumal carcinoid, highly differentiated follicular thyroid carcinoma, and other thyroid carcinomas. We additionally review the use of TTF1 staining to assist in differentiating these lesions from surrounding gynecologic epithelium, which is imperative in making such diagnoses. In highlighting these entities, we hope to provide practicing pathologists with an effective and concise review of these lesions to assist in more challenging cases of struma ovarii.

Ovarian strumal carcinoid: a case report.

BACKGROUND: Carcinoid tumors of the ovary are rare tumors, histopathologically classified as monodermal teratomas and somatic-type tumors arising from dermoid cysts. Their malignancy varies from borderline to malignant. Carcinoid tumors can occur in young and elderly women, and are sometimes seen in mature teratoma, struma ovarii, or mucinous cystadenoma as a nodule or tumor. Strumal carcinoid and mucinous carcinoid present as special types of carcinoid tumors of the ovary. CASE REPORT: This report describes a 56-year-old woman who presented with a large pelvic mass on abdominal ultrasonography during a medical examination. The diameter of the pelvic tumor was approximately 11 cm and was suspected to be ovarian cancer. The values of CA125 and CEA were above their reference intervals on preoperative examination. Abdominal total hysterectomy and bilateral salpingo-oophorectomy were performed. Intraoperative frozen-section histopathology suggested a diagnosis of mucinous adenocarcinoma; therefore, partial omentectomy and pelvic lymphadenectomy were also performed. Permanent-section histopathology led to a final diagnosis of strumal carcinoid of the ovary, stage IA (FIGO 2014). Six years post-operation, the patient had no sign of recurrence.

It Does Exist! Diagnosis and Management of Thyroid Carcinomas Originating in Struma Ovarii.

Thyroid carcinoma originating in struma ovarii comprises a small minority of all cases of struma ovarii. Given the rarity of this diagnosis, literature to guide evaluation and management is limited. The most common carcinoma originating from struma ovarii is papillary thyroid carcinoma. Treatment includes surgery, including a fertility sparing approach if disease is confined to the ovary, with consideration of total thyroidectomy and radioactive iodine ablation for high-risk pathologic features or disease spread beyond the ovary. This review discusses the histopathologic findings, molecular pathology, clinical implications and management, and prognosis of thyroid carcinomas originating in struma ovarii.

Computed tomography, magnetic resonance imaging, and positron emission tomography/computed tomography findings for the diagnosis of malignant struma ovarii: A case report.

Malignant struma ovarii (MSO) is an extremely rare disease arising from struma ovarii. Preoperative diagnosis is still challenging due to the lack of criteria for imaging findings. Herein, we report a case of MSO with suggestive imaging findings for a 50-year-old woman who presented with a pelvic tumor. The tumor did not typically show characteristic imaging findings of struma ovarii; however, the findings implied colloids of thyroid tissue within solid components on the magnetic resonance imaging (MRI) and computed tomography. Additionally, the solid components showed hyperintensity on diffusion-weighted image and hypointensity on apparent diffusion coefficient maps. Total abdominal hysterectomy, bilateral salpingo-oophorectomy, and omentectomy were performed. Histopathological examination revealed MSO of the right ovary, pT1aNXM0. The distribution of papillary thyroid carcinoma tissue corresponded to restricted diffusion area on MRI. In conclusion, the coexistence of imaging findings suggesting thyroid tissue and restricted diffusion in the solid component on MRI could indicate MSO.

Follicular carcinoma originating from struma ovarii: A case report.

INTRODUCTION: Follicular carcinoma originating from struma ovarii is a clinically rare low-grade malignant tumor. The pathological diagnosis of ovarian thyroid follicular carcinoma is predominantly based on the infiltrative growth and vascular involvement of tumor cell nests of different sizes in the ovarian parenchyma. PATIENT CONCERNS: Here we present a case of this malignancy in which the bilateral ovaries, right oviduct wall, myometrial surface, omentum, and bladder reflex were extensively involved Microscopically, the thyroid follicles in this case showed infiltrative growth of nodules of different sizes in the ovarian stroma. DIAGNOSIS: The epithelial layer of the follicles was atypical, but with no nuclear features of papillary thyroid carcinoma such as nuclear groove and nuclear pseudoinclusions. Immunohistochemistry showed positive expression of thyroglobulin, thyroid transcription factor-1, and cytokeratin19, with a Ki-67 index of 5% +. Immunohistochemical results combined with microscopic morphology allowed a diagnosis of follicular carcinoma originating from struma ovarii. INTERVENTIONS: After exclusion of contraindications to surgery, the patient underwent surgical exploration on July 26, 2022, during which frozen pathological examination was performed. OUTCOMES: The patient recovered well and was discharged. At the first follow-up visit in October 2022, the patient had an excellent survival. CONCLUSION: The analysis of the microscopic morphological characteristics and immunohistochemistry deepened our understanding of the pathological characteristics of ovarian and thyroid follicular carcinoma, and further provides a diagnostic reference for other clinicians who will encounter these conditions in the future.

Current state of management of struma ovarii and preoperative imaging features: A retrospective case series study of 18 patients at a single institution.

AIM: Even though 95% of struma ovarii are benign, it is often overtreated because of the difficulty to distinguish it from malignancy. In this study, our aim was to evaluate the current state of the preoperative diagnosis and the selection of the surgical procedure, and to improve preoperative diagnostic accuracy by retrospectively reviewing imaging findings. METHODS: We retrospectively reviewed the clinical course and imaging characteristics of 18 patients who were diagnosed postoperatively with struma ovarii, pathologically, at our institution between 2015 and 2021. RESULTS: The preoperative diagnoses included benign ovarian tumor in eight cases, borderline in four cases, and malignant in six cases. None of the cases were diagnosed as struma ovarii preoperatively. Of the seven patients who had confirmed a desire for future childbearing, four patients were suspected for borderline or malignant tumor preoperatively, and underwent abdominal adnexectomy. In patients without a desire for childbearing, laparoscopic surgery was performed in only 45% of the patients whose preoperative diagnosis was benign. On magnetic resonance imaging (MRI), 54% of the cases showed enhanced solid components, which is characteristic of malignant tumors, but diffusion restriction was observed in only 11%. On computed tomography (CT), 78% of the cases showed a high attenuation lesion reflecting thyroid tissue. CONCLUSIONS: Struma ovarii is difficult to distinguish from malignancy preoperatively, making the choice of surgical approach complicated. A comprehensive evaluation of diffusion-weighted MRI and CT findings may improve the accuracy of preoperative diagnosis of struma ovarii.

Papillary thyroid carcinoma in struma ovarii: management after surgery.

A woman in her 40s presented with a 3-month history of lower abdominal pain and intermenstrual bleeding. Ultrasound of the pelvis disclosed a 4 cm left adnexal mass. An MRI of the pelvis revealed a 2.2×3.6×2.4 cm solid, enhancing left ovarian mass. Due to high suspicion for malignancy, she underwent laparoscopic left salpingo-oophorectomy and resection of the tumour. Histopathology revealed papillary thyroid carcinoma in the background of struma ovarii as confirmed by thyroglobulin and thyroid transcription factor-1 positivity on immunohistochemistry. BRAF mutation analysis was negative. An ultrasound of the thyroid gland showed two low-risk nodules. An iodine-123 whole-body scan showed normal uptake in the thyroid gland. Thyroid-stimulating hormone (TSH) was 1.070 mcIU/mL (0.450-4.500), and thyroglobulin was 6.8 ng/mL (1.5-38.5). We risk-stratified this patient as low risk for recurrence. Risk stratification of malignant struma ovarii is essential to determine suitable thyroid targeting adjuvant therapy and reduce the risk of recurrence.

Malignant struma ovarii with thyroid-type papillary and poorly differentiated carcinoma: a case report.

BACKGROUND: Malignant struma ovarii is a very rare type of gynecologic cancer. Although its most common histological subtype is a pure type of papillary thyroid carcinoma containing two components, papillary carcinoma and poorly differentiated carcinoma, malignant struma ovarii is still extremely rare. As a result, the optimal treatment for this type of tumor remains uncertain due to its rarity. CASE PRESENTATION: A 62-year-old Japanese female presented with a pelvic tumor and clinical diagnosis of malignant tumor of the ovary. She underwent complete debulking surgery, total abdominal hysterectomy, bilateral salpingo-oophorectomy, and omentectomy. The histology of the ovarian tumor revealed malignant struma ovarii with thyroid-type papillary projections and poorly differentiated carcinoma. Because of the complete resection and the absence of distant metastasis, the patient did not receive any adjuvant therapy. At 24 months after surgery, she was free of disease. CONCLUSION: This is a rare case report of malignant struma ovarii, without recurrence, in which the component was papillary thyroid carcinoma mixed with poorly differentiated carcinoma. Foregoing adjuvant therapy might be one option for malignant struma ovarii in cases with complete resection and no distant metastasis. In addition, we should consider that long-term follow-up is needed for malignant struma ovarii.

Ovarian Strumal Carcinoid: Case Report, Systematic Literature Review and Pooled Analysis.

Background: Ovarian strumal carcinoid is a rare tumor in which thyroid (struma) and carcinoid components coexist. The disease is generally considered to be a borderline malignancy, however, cases with metastatic disease have been described. No data in the literature are available to guide diagnosis and therapy. Methods: We performed a pooled analysis and a systematic review of histopathological-confirmed strumal carcinoid cases published in the literature using the following keywords: "strumal carcinoid of the ovary", "strumal carcinoid case report". A case of strumal carcinoid tumor diagnosed and followed-up at the Medical Oncology Unit of Spedali Civili (Brescia, Italy) was also described and included. Results: Sixty-six eligible publications were identified, providing data from one hundred and seventeen patients, plus a case diagnosed at our institution. At presentation, among the eighty-eight patients with symptomatic disease, 37% of patients suffered from abdominal distention and 49% from pain due to a growing abdominal tumor mass, 37% from constipation (peptide YY was analyzed in only nine of them, resulting above the physiologic range). Surgery was the primary therapy in 99% of the patients. Three patients had metastatic disease at diagnosis and five patients underwent recurrence after radical surgery. Histology at disease recurrence concerned the thyroid component in two patients, the carcinoid component in two patients, both histologies in one patient. Median disease-free survival and overall survival in this series were not attained. Conclusion: Strumal carcinoid of the ovary generally presents a benign behavior and surgery is curative in most cases. However, a small group of patients with this disease can undergo disease recurrence due to both the thyroid and the neuroendocrine (carcinoid) components. A follow-up in radically operated patients is therefore needed, particularly in those with a voluminous disease at diagnosis.

Case Report: Recurrent Malignant Struma Ovarii With Hyperthyroidism and Metastases, A Rare Case Report and Review of the Literature.

Background: SO (Struma ovarii) is a rare form of ovarian teratoma which originates from ovarian dermoid cysts. Due to the rarity of this disease, relevant studies might not be sufficiently documented, especially cases with hyperthyroidism and multiple metastases. Case Presentation: A 40-year-old female patient was admitted to our hospital due to management of early pregnancy along with a recurrent abdominal and pelvic mass. Contrast-enhanced CT images showed an irregular mass (10.7 × 8.6 × 12.8 cm) located in the right side from the hypogastrium to the pelvic cavity and another mass (3.8 × 3.7 cm) in the liver. Laboratory examination showed that CA125 (Carbohydrate Antigen-125) was 118.10 U/mL, Tg (thyroglobulin) was >300 ng/ml, FT4 (free thyroxine) was 22.11 pmol/L, and TSH (thyroid-stimulating hormone) was <0.004 mIU/L. She subsequently underwent liver mass dissection, omentectomy, tumor dissection, peritoneal nodule resection, as well as rectal anterior wall nodule resection. The patient was diagnosed with malignant SO (papillary type) along with multiple metastases. Also, we conducted a literature review based on 290 SO cases from 257 articles. Conclusion: This study showed that malignant SO might be prone to relapse and metastasize (a metastatic rate of 52.94%) and therefore aggressive management might need to be recommended for malignant SO. Also, laparotomy might need to be recommended for large tumors that cannot be resected by laparoscopic surgery since these tumors might be prone to rupture and thus produce peritoneal implants. Furthermore, Graves' disease might need to be considered in the differential diagnosis.

Tyrosine kinase inhibitor treatment and long-term follow-up for metastatic malignant struma ovarii.

Metastatic malignant struma ovarii (MMSO) is a very rare disease (in the United States, less than one case in 10 million females annually). However, this incidence rate is due to a paucity of data regarding diagnosis, treatment, and follow-up. Herein, we describe the case of a 14-year-old female who presented with MMSO, which later metastasized and was followed up on for over 10 years. The patient underwent right oophorectomy surgery and was then treated with a combination of radioactive iodine followed by iodine scans to detect the absorption of radioiodine in the metastatic sites, and radiation therapy to treat skeletal lesions. She subsequently received treatment with the tyrosine kinase inhibitors (TKIs), sorafenib and then lenvatinib, as treatments for advanced disease, thereby achieving long-term disease stability. This case report, which adds to the limited data available on MMSO treatment, suggests that patients treated with a combination of radioactive iodine, radiation therapy, and TKIs can result in good responses and long-term overall survival.

Clinicopathological observation of mature teratoma with malignant transformation, a single center retrospective study.

Purpose: To investigate the clinicopathological features of mature teratoma with malignant transformation. Methods: Retrospectively analysis of 1179 cases mature teratoma was done from August 1999 to December 2019 in Institution. 14 cases of mature teratoma with malignant transformation were discussed mainly for the pathological characteristics and clinical manifestations. Results: 4 of them were less than 40 years old. All but one occurred in the ovaries, and the one was in the left anterior mediastinum which was the only male. The clinical manifestations of the patients were atypical. Imaging showed cystic solid mass. Surgery was performed. Polypoid mass, solid nodule and thickened area of cyst wall can be seen on the section of tumor. Pathological results show that there were 5 cases of squamous cell carcinoma, 3 cases of carcinoid, 2 cases of serous carcinoma and 2 cases of thyroid papillary carcinoma, 1 case of carcinosarcoma and 1 case of strumal carcinoid. Two cases of squamous cell carcinoma had pelvic and abdominal metastasis. Immunohistochemistry of case 14 showed that AE1/AE3, CD56, SYN, NSE, PSAP, CDX2 were positive in carcinoid. EMA and CK20 were positive in mucinous glands around carcinoid. Calretinin and inhibin were positive in the mesenchyme adjacent to intestinal mucinous gland. Conclusions: Teratoma with malignant transformation is a rare malignancy, although teratoma is a common germ cell tumor. And it's more common in patients over 40 years, especially those patients who were in menopause. Squamous cell carcinoma is the most common type and prone to metastasis. Strumal carcinoid was well-defined, but as an endocrine tumor, it may cause a series of digestive, respiratory or hormonal disorders. Therefore, the mature teratomas should be removed in time after detection.

Metastatic malignant struma ovarii: a case report and review of the literature on the management of malignant struma ovarii.

OBJECTIVES: To present a case of metastatic struma ovarii, to review the literature on malignant struma ovarii and to discuss the management in locoregional and metastatic disease. METHODS: We present a case of an 82-year-old patient with a malignant struma ovarii and liver metastasis. The patient was treated with pelvic surgery, total thyroidectomy, radioactive iodine therapy and TSH suppression therapy with levothyroxine. We performed a PubMed search for case reports of metastatic struma ovarii. RESULTS: 43 cases of metastatic struma ovarii were identified. 53.5% of patients presented with metastatic disease at diagnosis. Mean time to development of metastasis was 6.9 years in the group with initial locoregional disease. First-line treatment was pelvic surgery in all patients. Thyroidectomy was performed in 83.7% of patients, subsequent radioactive iodine therapy in 79.1%, followed by TSH suppression therapy in 46.5% of patients. Mean time of follow-up after diagnosis of metastases was 3.6 years, ranging from 0.5 to 24 years. At the end of the follow-up, 51.1% of patients were free of disease, 34.9% were alive with disease, 7.0% died of disease and 7.0% were lost to follow-up. CONCLUSION: The majority of patients with metastatic struma ovarii were treated with pelvic surgery, total thyroidectomy and radioactive iodine therapy. Suppression of TSH with levothyroxine was given in less than half of the patients. In non-metastatic setting, the same approach could be considered depending on the patient profile.

Malignant Struma Ovarii Τreated With Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC).

BACKGROUND/AIM: Malignant struma ovarii is an extremely rare tumor entity among ovarian tumors. In the presence of ascites and peritoneal metastases, the preoperative appearance may resemble the most common epithelial ovarian carcinoma (EOC) and accordingly, the surgical therapy may be identical if a preoperative histology diagnosis is not possible. The objective of this case report is to present a patient with histopathologically confirmed malignant struma ovarii who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) with the aim of complete tumor resection. CASE REPORT: This study reports on a patient with preoperatively proven peritoneal metastasis of an 18 cm ovarian tumor with large struma ovarii and papillary thyroid carcinoma within the struma, who was treated with CRS and HIPEC after neoadjuvant chemotherapy. CONCLUSION: This disease has a significantly better prognosis than EOC, however, HIPEC could provide an additional effect in examining the presence of peritoneal metastasis.