Long-Term Outcomes and Causes of Death among Medullary Thyroid Carcinoma Patients with Distant Metastases

Spontaneous and Treatment-Related Changes of Serum Calcitonin in Medullary Thyroid Cancer: Long-Term Experience in a Patient With Multiple Endocrine Neoplasia Type 2B

PURPOSE

Medullary thyroid carcinoma (MTC) in MEN2B syndrome is associated with germline RET mutation. Patients harboring de novo mutations are usually diagnosed at more advanced disease stages. We present a young woman with Met918Th mutation diagnosed with stage IV MTC at age 10 years.

METHODS

The disease progressed despite total thyroidectomy and multiple surgical interventions for cervical lymph node recurrences, leading to distant metastases in the fifth year after the initial diagnosis. Subsequently, she underwent five different types of tyrosine kinase inhibitor (TKI) treatments. The 17-year disease course was divided into periods defined by four surgical interventions and sequential treatment intervals with four multikinase (sunitinib, vandetanib, cabozantinib, and lenvatinib) and one RET-selective TKI (selpercatinib). Tumor growth for different phases of spontaneous development and drug treatment intervals was characterized by changes in serial log-transformed calcitonin measurements (n = 114).

RESULTS

Three operations (one for calcitonin-producing adrenal pheochromocytoma) were associated with drops in calcitonin levels. All of the nonselective TKIs were stopped due to adverse effects. As reflected by the negative calcitonin doubling rate, the best treatment response was observed with selpercatinib, which was associated with an initial large drop followed by a decreasing calcitonin trajectory over 514 days without any major side effects.

CONCLUSION

This case of MEN2B medullary thyroid cancer with long-term survival presents how the effectiveness of different treatment modalities can be estimated using log-transformed calcitonin levels. Furthermore, our experience supports the view that serial calcitonin measurements may be more sensitive than radiological follow-up in advanced MTC. Our patient also represents a new case of rarely reported calcitonin-producing pheochromocytomas.

Metastatic Neuroendocrine Neoplasms to the Pancreas: Two Unusual Cases and a Review of the Literature

Neuroendocrine tumor metastases to the pancreas are rare, and they share substantial overlap with the significantly more common primary pancreatic neuroendocrine neoplasms, representing a potential diagnostic pitfall. Elucidating whether a neuroendocrine tumor within the pancreas is a primary neoplasm versus a metastasis has significant prognostic and treatment implications. Correlation with clinical history and imaging as well as incorporating an appropriate immunohistochemical panel are essential to establish the correct diagnosis. Herein, we present 2 rare neuroendocrine tumors that metastasized to the pancreas: a medullary thyroid carcinoma and an atypical carcinoid tumor of lung origin. We also provide a brief review of the literature.

Risk factor analysis of distant metastases in patients with primary medullary thyroid cancer: a population-based study

OBJECTIVE

Medullary thyroid carcinoma has a high rate of recurrence and distant metastasis. The aim of this study was to investigate the risk factors for distant metastasis in patients with primary medullary thyroid carcinoma.

METHODS

Patients diagnosed with primary medullary thyroid cancer between 2010 and 2015 were enrolled using the Surveillance, Epidemiology, and End Results (SEER) database. Patient demographics and tumor clinicopathological features were evaluated to identify potential risk factors for distant metastasis in patients with primary medullary thyroid cancer. Univariate and multivariate logistic regression analyses were used to determine independent risk factors for distant metastasis in patients with primary medullary thyroid carcinoma. All statistical analyses were performed using SPSS statistical software (version 27.0). A two-tailed P < 0.05 was considered statistically significant.

RESULTS

We collected 685 patients with primary medullary thyroid carcinoma, 40 of whom (5.84%) developed distant metastases. Univariate logistic regression analysis showed that except marital status, age, sex, race, pT stage, N stage, multifocal and capsular infiltration were significantly correlated with distant metastasis of medullary thyroid carcinoma. Multivariate logistic regression analysis showed that patients aged ≤ 18 years or > 55 years, Black race, higher pT stage and N stage were independent risk factors for distant metastasis of medullary thyroid carcinoma.

CONCLUSIONS

This study found that ≤ 18 years or > 55 years, black race, higher pT stage and N stage were significantly associated with distant metastasis of medullary thyroid cancer. This is important for clinicians to identify patients at high risk of distant metastasis in a timely manner.

Early postoperative prediction of the risk of distant metastases in medullary thyroid cancer

Purpose

The purpose of this study was to develop and validate a nomogram for estimating the risk of distant metastases (DM) in the early postoperative phase of medullary thyroid cancer (MTC).

Patients and methods

We retrospectively reviewed cases of patients diagnosed with MTC from the Surveillance, Epidemiology, and End Results (SEER) database from 2007 to 2017. In addition, we gathered data on patients who diagnosed as MTC at Department of Thyroid Surgery in the First Hospital of Jilin University between 2009 and 2021. Four machine learning algorithms were used for modeling, including random forest classifier (RFC), gradient boosting decision tree (GBDT), logistic regression (LR), and support vector machine (SVM). The optimal model was selected based on accuracy, recall, specificity, receiver operating characteristic curve (ROC), and area under curve (AUC). After that, the Hosmer-Lemeshow goodness-of-fit test, the brier score (BS) and calibration curve were used for validation of the best model, which allowed us to measure the discrepancy between the projected value and the actual value.

Results

Through feature selection, we finally clarified that the following four features are associated with distant metastases of MTC, which are age, surgery, primary tumor (T) and nodes (N). The AUC values of the four models in the internal test set were as follows: random forest: 0.8786 (95% CI, 0.8070-0.9503), GBDT: 0.8402 (95% CI, 0.7606-0.9199), logistic regression: 0.8670(95%CI,0.7927-0.9413), and SVM: 0.8673 (95% CI, 0.7931-0.9415). As can be shown, there was no statistically significant difference in their AUC values. The highest AUC value of the four models were chosen as the best model since. The model was evaluated on the internal test set, and the accuracy was 0.84, recall was 0.76, and specificity was 0.87. The ROC curve was drawn, and the AUC was 0.8786 (95% CI, 0.8070-0.9503), which was higher than the other three models. The model was visualized using the nomogram and its net benefit was shown in both the Decision Curve Analysis (DCA) and Clinical Impact Curve (CIC).

Conclusion

Proposed model had good discrimination ability and could preliminarily screen high-risk patients for DM in the early postoperative period.

Diagnostic dilemma in a patient with history of medullary thyroid carcinoma and abnormal serum liver enzymes; a case report with six years follow up

BACKGROUND

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor that originates from parafollicular C-cells. Calcitonin (Ctn) and carcinoembryonic antigen (CEA) are useful biomarkers for monitoring MTC cases.

CASE PRESENTATION

Here, we describe a 48-year-old woman, who presented in 2014 with bilateral thyroid nodules. Report of fine needle aspiration was suspicious for MTC; initial laboratory evaluation showed serum Ctn level of 1567 pg/mL. After excluding type 2 multiple endocrine neoplasia syndrome clinically, total thyroidectomy and neck lymph node dissection were performed. The final histopathological diagnosis was right lobe MTC with neither vascular invasion nor lymph node involvement. On regular follow-up visits, Ctn and CEA levels have been undetectable, and repeated cervical ultrasonographic exams were unremarkable from 2014 to 2021. As liver enzymes became elevated in 2016, the patient was further evaluated by a gastroenterologist. Abdominopelvic ultrasonography revealed a coarse echo pattern of the liver parenchyma with normal bile ducts. A liver fibroscan showed a low fibrosis score (7kPa). The patient was recommended to use ursodeoxycholic acid. According to the progressive rise of liver enzymes with a cholestatic pattern in October 2020, a liver biopsy was performed that showed tiny nests of neuroendocrine-like cells with a background of primary biliary cholangitis (PBC). Immunohistochemical stainings were positive for chromogranin A (CgA), and synaptophysin and negative for Ctn, CEA, and thyroglobulin. Further imaging investigations did not reveal any site of a neuroendocrine tumor in the body. Considering normal physical exam, imaging findings, as well as normal serum levels of Ctn, CEA, CgA, and procalcitonin, the patient was managed as a PBC.

CONCLUSION

In follow-up of a patient with MTC, we reported progressively increased liver enzymes with a cholestatic pattern. Liver biopsy revealed nests of neuroendocrine-like cells with a background of PBC, the findings that might suggest acquiring neuroendocrine phenotype by proliferating cholangiocytes.

Establishment and validation of a nomogram model for predicting distant metastasis in medullary thyroid carcinoma: An analysis of the SEER database based on the AJCC 8th TNM staging system

OBJECTIVE

Medullary thyroid carcinoma (MTC) patients with distant metastases frequently present a relatively poor survival prognosis. Our main purpose was developing a nomogram model to predict distant metastases in MTC patients.

METHODS

This was a retrospective study based on the Surveillance, Epidemiology, and End Results (SEER) database. Data of 807 MTC patients diagnosed from 2004 to 2015 who undergone total thyroidectomy and neck lymph nodes dissection was included in our study. Independent risk factors were screened by univariate and multivariate logistic regression analysis successively, which were used to develop a nomogram model predicting for distant metastasis risk. Further, the log-rank test was used to compare the differences of Kaplan-Meier curves of cancer-specific survival (CSS) in different M stage and each independent risk factor groups.

RESULTS

Four clinical parameters including age > 55 years, higher T stage (T3/T4), higher N stage (N1b) and lymph node ratio (LNR) > 0.4 were significant for distant metastases at the time of diagnosis in MTC patients, and were selected to develop a nomogram model. This model had satisfied discrimination with the AUC and C-index of 0.894, and C-index was confirmed to be 0.878 through bootstrapping validation. A decision curve analysis (DCA) was subsequently made to evaluate the feasibility of this nomogram for predicting distant metastasis. In addition, CSS differed by different M stage, T stage, N stage, age and LNR groups.

CONCLUSIONS

Age, T stage, N stage and LNR were extracted to develop a nomogram model for predicting the risk of distant metastases in MTC patients. The model is of great significance for clinicians to timely identify patients with high risk of distant metastases and make further clinical decisions.