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.

Struma ovarii with synchronous ascites and elevated CA125 level: a retrospective cohort study.

BACKGROUND: Benign struma ovarii (SO) with synchronous ascites and elevated CA125 level is extremely rare that the incidence, clinical characteristics, and risk factors remain unclear. METHODS: We conducted a retrospective study of patients with SO treated in our hospital between 1980 and 2022. Logistic regression was used to identify potential risk factors for SO patients presenting with ascites and elevated CA125 levels. The receiver operating characteristic (ROC) curve was used to evaluate the predictive performance of the identified risk factors. RESULTS: A total of 21 patients with synchronous ascites and elevated CA125 levels were identified in 229 patients with SO, the crude incidence rate was 9.17%, and four patients (1.75%) had pseudo-Meigs' syndrome. Ascites were completely involuted within 1 month postoperatively and the serum CA125 level decreased to normal between 3 d and 6 weeks after surgery. Multivariate logistic regression showed that age ≥49 years (OR 3.71, 95% CI 1.29 - 10.64, p = 0.015), tumor size ≥10.0 cm (OR 8.79, 95% CI 3.05 - 25.35, p < 0.001), and proliferative SO (OR 11.16, 95% CI 3.01 - 41.47, p < 0.001) were the independent risk factors for patients presenting ascites and elevated CA 125 level. The ROC curve revealed that the predictive performance for age and tumor size was unsatisfactory with an area under the curve (AUC) was 0.646 and 0.682, respectively. Linear regression demonstrated that the serum CA125 level has a moderate positive correlation with the volume of ascites (log2CA125 = 0.6272*log2ascites + 2.099, p = 0.0001, R2 = 0.5576). CONCLUSIONS: Less than one-tenth of patients with SO would present ascites and elevated CA125 levels, while age ≥49 years, tumor sizes ≥10 cm, and the presence of proliferative SO were the risk factors.

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.

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.

Struma ovarii with massive ascites mimicking ovarian carcinoma treated with conservative laparoscopic surgery: a case report.

Struma ovarii is a rare taratoma that accounts for 0.5-1% of all ovarian tumors. It is sometimes difficult to differentiate struma ovarii from ovarian carcinoma. We encountered a case of struma ovarii that was suspected to be malignant due to the accumulation of massive ascites and an elevated CA125 level. It was successfully treated with laparoscopic surgery.A 37-year-old nulliparous woman consulted a local physician with a chief complaint of abdominal distention. Computed tomography (CT) of the abdomen revealed a pelvic tumor with a large amount of ascites. She was referred to our department. Contrast-enhanced magnetic resonance imaging (MRI) and CT showed bilateral ovarian tumors with multicystic and solid components. CA125 level was markedly elevated. Two cytological examinations of ascites showed no malignant cells. Preoperatively, malignancy was strongly suspected, but considering the possibility of a benign ovarian tumor, laparoscopic surgery was scheduled. During laparoscopic surgery, 4,850 mL of ascites were aspirated, and the left adnexa was removed. Intraoperative rapid pathology suggested struma ovarii with no evidence of malignancy. Postoperative pathology showed mature teratoma and struma ovarii.Although struma ovarii is benign in 90-95% of cases, there have been scattered case reports in which suspected malignancy led to unnecessary or excessive surgery. We propose that appropriate preoperative imaging and accurate intraoperative rapid pathology can prevent excessive surgery, conservative or laparoscopic excisions should be considered.

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.

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.

Proposed Risk Stratification and Patterns of Radioactive Iodine Therapy in Malignant Struma Ovarii.

Introduction: Malignant struma ovarii (MSO) is a rare thyroid cancer arising within an ovarian teratoma. While surgical excision of the primary tumor is widely accepted as standard of care, recommendations for adjuvant treatment of MSO-whether or not to administer radioactive iodine (RAI)-are based largely on case reports and remain debated. In this study, we aimed to propose a risk stratification and analyze RAI utilization patterns in MSO cases. Methods: The National Cancer Database (NCDB) was queried for patients with MSO between 2004 and 2016. Demographic, oncological, and clinicopathologic data were compared between groups using Fisher's exact test. Kaplan-Meier curves were used to estimate overall survival (OS), and variables associated with OS were assessed via univariate Cox regression. We adapted the 2015 American Thyroid Association risk guidelines for MSO patients. We stratified patients into low-, intermediate-, and high-risk groups using metastasis, extraovarian extension, lymphovascular invasion, lymph node status, surgical margins, tumor size, and grade. Risk stratification, demographic, oncological, and clinicopathologic data were compared between the groups receiving and not receiving RAI therapy. We then queried the Surveillance, Epidemiology, and End Results (SEER) 18 registry for patients with MSO between 2000 and 2018 to confirm our risk stratification analysis. Results: In the NCDB analysis, a total of 158 patients were identified, and 19 received RAI. RAI therapy was associated with distant metastasis (p = 0.005) and lymph node status (p = 0.012). Twenty-one NCDB patients were stratified as high risk, and 30% of high-risk patients received RAI. High-risk stratification was associated with decreased OS via univariate Cox regression (hazard ratio = 4.0 [95% confidence interval 1.11-14.26], p = 0.034). In our subsequent analysis using the SEER registry, there were 95 MSO patients, and 18 received RAI. Again, the majority of high-risk patients did not receive RAI, with only 41% of high-risk patients receiving RAI. Conclusions: MSO is a rare malignancy with apparently variable and inconsistent patterns of postoperative RAI administration. The risk stratification described here provides a framework to identify patients potentially at risk for mortality, and utilization of RAI in this group should be studied further.

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.

Metastatic follicular carcinoma arising from struma ovarii.

Struma ovarii (SO) is an uncommon monodermal teratoma predominantly composed of mature thyroid tissue. Approximately 5% of SO are malignant; however, metastases are rare. A single female in her 40s, with a medical history of Graves' disease and bilateral cystectomy 10 years prior for right endometriotic cyst and left SO, presented with an enlarging abdominal mass for 4 months. Ultrasound pelvis showed a 13.8 cm left adnexal heterogeneous solid-cystic mass with internal septations and vascularity. She underwent open left salpingo-oophorectomy and resection of fibrous nodules from the right infundibulo-pelvic ligament and fallopian tube. Histology showed highly differentiated metastatic follicular carcinoma. She subsequently underwent total thyroidectomy, total hysterectomy, right salpingo-oophorectomy, tumour debulking and omentectomy followed by radioactive iodine treatment. Four-year follow-up did not show tumour recurrence or metastases. Due to its rarity, there are no well-established guidelines for the management and follow-up of metastatic follicular carcinoma arising from SO.

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.

Boba sign with a twist - A variant presentation of a mature cystic teratoma complicated by torsion and rupture.

While mature cystic teratomas are relatively common ovarian neoplasms typically comprising of multiple embryologic cell types, a specific monodermal subtype involving thyroid tissue, struma ovarii, can rarely be seen. This case reviews typical imaging characteristics with MRI and ultrasound of struma ovarii and details possible complications from these masses with intraoperative and histologic correlation.

Malignant struma ovarii: From case to analysis.

AIM: To evaluate the clinico-pathologic features, treatment options, prognostic factors, and survival outcomes of malignant struma ovarii based on a systematic literature review in association with our case study. METHODS: A systematic review of the medical literature was performed to identify articles about malignant struma ovarii from January 1983 until July 2020. We evaluated 178 cases. RESULTS: The 5-year progression-free survival (PFS) and overall survival (OS) of the entire cohort was 72.5% and 91%, respectively. In univariate analysis, younger age (<43 years), whole strumal cyst diameter >95 mm, presence of a histologic type other than papillary classic-type thyroid carcinoma within the tumor and lymphovascular space invasion were related to poor PFS. Patients who received radioactive iodine ablation (RIA) before the treatment failure had significantly higher PFS than those who did not receive RIA (94.9% vs. 64.8%, p = 0.041, respectively). In univariate analysis, PFS was significantly higher in patients who underwent gynecologic surgery followed by thyroidectomy and RIA compared with those who had surgical treatment only (94.5% vs. 64.3%, p = 0.05, respectively). However, this result could not be identified as an independent prognostic factor in multivariate analysis (p = 0.207). Younger age and absence of capsular involvement were related to significantly increased OS. Histologic type was the only independent prognostic factor for PFS (hazard ratio: 3.30, 95% confidence interval: 1.122-9.748; p = 0.030) CONCLUSION: The most common histologic subtype was the papillary classic type. The presence of a histologic type other than the classic papillary thyroid carcinoma within the tumor was an independent adverse prognostic factor.

Struma ovarii and peritoneal strumosis during pregnancy.

BACKGROUND: Struma ovarii is a special type of ovarian dermoid cyst and accounts for approximately 2-3 % of all dermoid tumours. Benign struma ovarii may manifest as distant metastasis, called peritoneal strumosis, which makes it biologically similar to malignancy, and has been reported in limited cases but never discovered during pregnancy. CASE PRESENTATION: We report a patient with a history of right struma ovarii cystectomy. During pregnancy, pelvic masses with non-specific clinical presentation were found again. During the caesarean section, contralateral struma ovarii with dissemination of nodules in the peritoneal cavity was found, and pathology revealed that the masses were thyroid follicle ovarian goitres. DISCUSSION AND CONCLUSIONS: Recurrent benign struma ovarii with extraovarian dissemination is a rare aggressive clinical manifestation different from malignancy. It is emphasized that adequate assessment and complete resection of suspicious masses are of great importance.