FIGO Stage IV and Age Over 55 Years as Prognostic Predicators in Patients With Metastatic Malignant Struma Ovarii

Personalized approach to malignant struma ovarii: Insights from a web-based machine learning tool

OBJECTIVES

Malignant struma ovarii (MSO) is a rare ovarian tumor characterized by mature thyroid tissue. The diverse symptoms and uncommon nature of MSO can create difficulties in its diagnosis and treatment. This study aimed to analyze data and use machine learning methods to understand the prognostic factors and potential management strategies for MSO.

METHODS

In this retrospective cohort, the Surveillance, Epidemiology, and End Results (SEER) database provided the data used for this study's analysis. To identify the prognostic variables, we conducted Cox regression analysis and constructed prognostic models using five machine learning algorithms to predict the 5-year survival. A validation method incorporating the area under the curve of the receiver operating characteristic curve was used to validate the accuracy and reliability of the machine learning models. We also investigated the role of multiple therapeutic options using the Kaplan-Meier survival analysis.

RESULTS

The study population comprised 329 patients. Multivariate Cox regression analysis revealed that older age, unmarried status, chemotherapy, and the total number of tumors in patients were poor prognostic factors. Machine learning models revealed that the multilayer perceptron accurately predicted outcomes, followed by the random forest classifier, gradient boosting classifier, K-nearest neighbors, and logistic regression models. The factors that contributed the most were age, marital status, and the total number of tumors in the patients.

CONCLUSION

The present study offers a comprehensive approach for the treatment and prognosis assessment of patients with MSO. The machine learning models we have developed serve as a practical, personalized tool to aid in clinical decision-making processes.

Malignant struma ovarii with synchronous primary papillary thyroid cancer in the neck: A case report and literature review

Malignant struma ovarii (MSO) with synchronous primary thyroid cancer in the neck is extremely rare and lacks a treatment consensus. A 44-year-old woman presenting with a left ovarian cyst was admitted to Peking Union Medical College Hospital (Beijing, China) Ultrasonography showed a 6 cm solid-cystic left ovarian mass with plentiful blood signals. Other notable findings were an elevated CA125 level and a suspected malignant thyroid nodule. A unilateral salpingo-oophorectomy (USO) was conducted, and the surgical pathology was papillary thyroid cancer (PTC) arising in a struma ovarii. The patient underwent a total thyroidectomy and cervical lymph node dissection, and the pathology of the right lobe nodule was follicular-variant PTC without capsule invasion or lymph node metastasis (5 mm; pT1aN0M0). No further adjuvant therapy was administered. The serum thyroglobulin value was normal before surgery and was undetectable after thyroidectomy. During regular follow-up examinations over 4 years, the patient remained well with no evidence of disease (NED). In a literature review, another 13 cases of MSO coexisting with cervical thyroid cancer that had reported outcomes were found. The MSO was confined to the ovary in all cases. A total of nine patients received radioiodine therapy (RAI) treatment after total thyroidectomy. Two patients relapsed and were successfully cured with RAI after the initial surgery Only one patient died due to another disease, while 11 patients showed NED and the remaining patient was alive with the disease after a median follow-up time of 2 years. This data suggests that USO with personalized RAI may be a preferred option for MSO confined to the ovary plus synchronous primary thyroid cancer due to the conferred satisfactory prognosis.

Incidence, clinical characteristics, and survival outcomes of ovarian strumal diseases: a retrospective cohort study

BACKGROUND

Struma ovarii (SO) is a rare tumor and may transform into ovarian strumal carcinoid (OSC) and/or malignant struma ovarii (MSO), but the incidence, clinical characteristics, and survival outcomes have not been well defined.

METHODS

We conducted a retrospective study of patients with ovarian strumal diseases treated in the our hospital between 1980 and 2022. Subgroup analyses of SO, OSC, and MSO were subsequently performed.

RESULTS

A total of 275 cases (2.14%) were identified in a cohort of 12,864 patients with ovarian teratomas, where SO, OSC, and MSO accounted for 83.3%, 12.0%, and 4.7% of cases, respectively. There were no significant differences in age, tumor sizes, elevated tumor markers, and ascites among the three subgroups. At initial treatment, all patients with SO or OSC had FIGO stage I disease except one SO patient presenting metastatic disease, ten patients had MSO confined to the ovary, whereas other three patients had metastatic diseases. Two patients with SO respectively relapsed at peritoneum and anterior mesorectum, while none of the OSC patients presented tumor recurrence or death despite different surgical procedures employed. The 5-year recurrence-free survival rate was 88.9%, and only one death occurred at 9.5 years after diagnosis in patients with MSO. Radioiodine therapy showed satisfactory therapeutic efficacy, but these patients showed poor responses to the chemotherapy.

CONCLUSION

2.14% of ovarian teratoma could be classified as SO, of which 12.0% and 4.7% of SO may transform into OSC and MSO, repsectively. The survival outcomes were excellent even after SO transformed into OSC or MSO.

SYNOPSIS

SO occupied 2.14% of ovarian teratoma, where 12.0% and 4.7% of SO may transform into OSC and MSO, respectively, and had excellent survival outcomes.

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.

Clinical Characteristics, Treatment, and Outcomes of Peritoneal Strumosis: A Report of Three Cases and Systematic Review

Benign struma ovarii (SO) has a probability of metastasis named "peritoneal strumosis", which is extremely rare, such that the specific clinical characteristics, treatment options, and survival outcomes remain unclear. We screened three cases of peritoneal strumosis among 229 cases of SO treated in our hospital. Case 1 was a 36-year-old woman with extensive peritoneal seedings at initial presentation. The second one was a 49-year-old with trocar site implant 11 years after laparoscopic adnexectomy. Case 3 was a 45-year-old woman who had an isolated lesion at the anterior surface of the rectum after laparoscopic ovarian cystectomy for SO 14 years ago. These three patients underwent surgery without any adjuvant treatment and remained disease-free after 30 to 68 months. A systematic review was then conducted and another 16 cases were identified. More than half (10/19, 52.6%) of the patients had previous SO-related ovarian surgery. The median interval between prior SO-related surgery and the initial presentation of peritoneal strumosis was 10.0 years; both regional and distant metastasis, even in the liver, lung, and heart, could also be affected. Surgery was the mainstay therapy (18/19, 94.7%), in which six patients (6/19, 31.7%) were treated with total thyroidectomy (TT) followed by radioiodine (RAI) therapy. Postoperative chemotherapy was only applied in one patient, and the last one only received a diagnostic biopsy without further treatment. Recurrence was noted in two patients with a median recurrence-free survival of 12 years, where surgical excision and RAI were then performed. No death occurred after a mean follow-up of 53 months, where 12 patients achieved no evidence of disease and five were alive with the disease. Peritoneal strumosis has unpredictable biological behaviors and the crude incidence is approximately 1.3% in SO. Patients with peritoneal strumosis have excellent survival outcomes, irrespective of different treatment strategies employed. Surgery with personalized RAI should be preferred and long-term close monitoring is recommended.

Clinical characteristics and survival outcomes in patients with ovarian strumal carcinoid

BACKGROUND

Ovarian strumal carcinoid is an extremely rare ovarian malignant tumor with limited data on clinical characteristics and survival outcomes.

METHODS

A retrospective study of 119 patients was conducted, including 98 cases identified from literature review, and their clinical characteristics were investigated. The overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and potential prognostic factors of these patients were also evaluated.

RESULTS

Lesions of 115 cases were confined to the ovarian while four patients presented with extra-ovarian disease upon initial diagnosis. Surgical treatment options performed in this cohort varied, 5.0% received ovarian cystectomy, 36.1% received unilateral salpingo-oophorectomy (USO), 7.6% received bilateral salpingo-oophorectomy (BSO), 42.0% received hysterectomy with BSO, and 8.4% underwent debulking surgery. Moreover, one patient did not undergo any surgery. No postoperative adjuvant therapy was administered in 89.9% patients, while 7.6% and 2.5% received adjuvant radiotherapy and chemotherapy, of which two patients received combined radiation and chemotherapy. At the final follow-up, 89.1% patients showed no evidence of the disease, and 5.0% were alive with the disease. Only seven deaths occurred, with two attributed to the tumor. The 5-year, 10-year, and 20-year OS rates were 96.0%, 85.0%, and 85.0%, respectively, with a 15-year recurrence rate of 4.4%. The 5-year and 20-year DSS rate were 98.5% and 95.9%. Multivariate Cox regression showed age ≥ 55 years was the only risk factor associated with the OS (P = 0.014, OR 7.988; 95% CI 1.519 - 42.004). However, the univariate and multivariate Cox regression showed no potential risk factor for RFS and DSS.

CONCLUSION

Patients with ovarian strumal carcinoid have an excellent prognosis irrespective of the surgical option. Conservative surgery especially USO with individualized adjuvant therapy is recommended.

Survival Outcomes and Prognostic Predictors in Patients With Malignant Struma Ovarii

Background: Malignant struma ovarii (MSO) is an extremely rare ovarian malignant tumor and there is limited data on the survival outcomes and prognostic predictors of MSO. The objectives of this study were to investigate the disease-free survival (DFS), overall survival (OS), and disease-specific survival (DSS) rates of patients with MSO, and also evaluate the prognostic factors in this population.

Methods: A retrospective study was conducted and 194 cases of MSO were selected. DFS was assessed by the logistic regression, OS by the Kaplan–Meier method, and DSS was evaluated by the Cox regression.

Results: The median age of these patients was 46.0 years; 142 cases (73.2%) were confined to the ovary and 52 cases (26.8%) had extraovarian metastasis at the initial diagnosis of MSO. During the follow-up, 75.3% of these patients showed no evidence of disease and 18.0% were alive with disease. Only 13 deaths occurred, with 10 attributed to MSO. The 5, 10, and 15-year OS rates were 91.4, 87.7, and 83.5%, respectively. The 5, 10, and 15-year DSS rates were 93.8, 90.0, and 85.7%, respectively. Logistic regression revealed that International Federation of Gynecology and Obstetrics (FIGO) stage IV was the only risk factor for DFS [p < 0.001; odds ratio (OR) 7.328; 95% CI 3.103–16.885, FIGO stage IV vs. stage I; p = 0.021; OR 4.750, 95% CI 1.264–17.856, FIGO stage IV vs. stage II-III]. The multivariate Cox regression analysis showed that poor differentiation was the only risk factor for both OS (p = 0.005, OR 6.406; 95% CI 1.730–23.717) and DSS (p = 0.001, OR 9.664; 95% CI 2.409–38.760), while age ≥45 years was the prognostic predictor for OS (p = 0.038, OR 4.959; 95% CI 1.093–22.508).

Conclusion: Survival outcomes were excellent in patients with MSO, irrespective of the treatment strategy, FIGO stage IV, age ≥45 years, and poor differentiation of tumors were the independent risk factors.

Malignant Struma Ovarii with Concurrent Thyroid Cancer: Outcomes during and after Pregnancy

INTRODUCTION

Struma ovarii (SO) is a rare ovarian teratoma characterized by the presence of thyroid tissue in more than 50% of the tumor. Malignant transformation is rare and the most common associated malignancy is papillary thyroid carcinoma (PTC). Pregnancy may represent a stimulus to differentiated thyroid cancer (DTC) growth in patients with known structural or biochemical evidence of disease, but data about malignant SO evolution during pregnancy are rare. We present the first reported case of a pregnant patient with malignant SO and biochemical evidence of disease.

CASE PRESENTATION

A previously healthy 35-year-old female diagnosed with a suspicious left pelvic mass on routine ultrasound was submitted to laparoscopic oophorectomy which revealed a malignant SO with areas of PTC. A 15-mm thyroid nodule (Bethesda V in the fine-needle aspiration cytology) was detected by palpation and total thyroidectomy was performed. Histology revealed a 15 mm follicular variant of PTC (T1bNxMx). Subsequently, she received 100 mCi of radioactive iodine therapy (RAIT) with the whole-body scan showing only moderate neck uptake. Her suppressed thyroglobulin (Tg) before RAI was 1.1 ng/mL. She maintained biochemical evidence of disease, with serum Tg levels of 7.6 ng/mL. She got pregnant 14 months after RAIT, and during pregnancy, Tg increased to 21.5 ng/mL. After delivery, Tg decreased to 14 ng/mL but, 6 months later, rose again and reached 31.9 ng/mL on the last follow-up visit. TSH was always suppressed during follow-up. At the time of SO diagnosis, a chest computed tomography scan showed 4 bilateral lung micronodules in the upper lobes which were nonspecific, and 9 months after diagnosis, a pelvic MRI revealed a suspicious cystic nodule located on the oophorectomy bed. These lung and pelvic nodules remained stable during follow-up. Neck ultrasonography, abdominal MRI, and fluorodeoxyglucose-positron emission tomography showed no suspicious lesions.

DISCUSSION/CONCLUSION

As for DTC, pregnancy seems to represent a stimulus to malignant SO growth. This can be caused by the high levels of estrogen during pregnancy that may bind to receptors in malignant cells and/or by the high levels of hCG which is known to stimulate TSH receptors.

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.

Clinical characteristics and survival outcomes of malignant struma ovarii confined to the ovary

Background

Malignant struma ovarii (MSO) is a unique type of ovarian malignancy that data on the survival outcome is limited and management strategy remains controversial due to its extreme rarity.

Methods

To investigate the clinical characteristics and treatment options in patients with MSO confined to the ovary, while also evaluating the recurrent-free survival (RFS) and overall survival (OS) rate in this population, a retrospective study was conducted. One hundred twenty-five cases of MSO confined to the ovary were enrolled and their clinical characteristics, treatment strategies, and results of follow-up were analyzed. OS and RFS were assessed by Kaplan-Meier analyses and Cox regression models.

Results

The most common pathological subtype in this cohort was papillary carcinoma (44.8%). Other reported subtypes, in order of prevalence, were follicular variant of papillary carcinoma, follicular carcinoma, and mixed follicular-papillary carcinoma. Surgical treatment options varied in this cohort that 8.0% of the patients received ovarian cystectomy, 33.6% underwent unilateral salpingo-oophorectomy (USO), 5.6% received bilateral salpingo-oophorectomy (BSO), 21.6% received total abdominal hysterectomy with BSO (TAH/BSO), and 17.6% were treated with debulking surgery; 20.0% of them received radioiodine therapy (RAI). Twenty-seven patients experienced recurrence with a median RFS of 14.0 years (95% confidence interval [CI], 9.5–18.5). The 5-year and 10-year recurrent rate were 27.1, 35.2%, respectively. Eight patients died during follow-up, with five attributed to MSO; the 5-year, 10-year, and 20-year OS rate was 95.3, 88.7 and 88.7%, respectively. However, the univariate and multivariate Cox regression showed no potential risk factor for RFS and OS.

Conclusion

Patients with MSO confined to the ovary had an excellent survival outcome, despite varied treatment strategies, and the recurrent rate was relatively high. We recommend USO as the preferred surgical option in this population since more aggressive surgery does not improve outcomes and the benefits of RAI are uncertain.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08118-7.

Metastatic Malignant Struma Ovarii and Graves' Disease: A Rare Occurrence

Objective

Malignant struma ovarii (SO) is a rare condition. Although there have been a few reported cases of malignant SO with coexisting Graves’ disease (GD), the exact incidence of metastasis in these cases is not known. We report a rare case of metastatic malignant SO coexisting with GD.

Methods

Clinical examination, pelvic ultrasound, and histopathology of the resected tumor were performed, followed by iodine-131 (I-131) and whole body scan. Antithyroglobulin titers were postoperatively followed.

Results

A 43-year-old woman with a history of left ovarian cystic teratoma with SO resected 8 years ago and recently diagnosed GD presented with lower abdominal fullness. Pelvis ultrasound showed a 13.8-cm left adnexal mass, and she underwent left salpingo- oophorectomy. Histology confirmed an intraovarian thyroid tissue housing a highly differentiated follicular thyroid carcinoma, with metastatic peritoneal deposits. She underwent completion surgery and total thyroidectomy. Histology showed no evidence of intrathyroidal malignancy. I-131 therapy was administered, and posttherapeutic I-131 whole body scan revealed a remnant disease. She was started on suppressive levothyroxine therapy and remained clinically well at her 1-year follow-up with downtrending antithyroglobulin titers.

Conclusion

The coexistence of malignant SO and GD is very rare, and even rarer is the coexistence of metastasis malignant SO and GD. To the best of our knowledge, this is the first reported case of metastatic malignant SO in the setting of GD.