Treatment and survival of patients with insular thyroid carcinoma: 508 cases from the National Cancer Data Base

Insular thyroid carcinoma: epidemiological pattern, factors contributing to recurrence and distant metastasis

BACKGROUND

Insular thyroid carcinoma is a rare subtype of thyroid cancer that constitutes an intermediate entity between differentiated (papillary & follicular) and undifferentiated (anaplastic) thyroid cancer.

METHODS

This is a retrospective study that included all the patients with insular carcinoma of the thyroid gland who underwent surgical treatment in our department from January 2009 to December 2023. The epidemiological, clinical, and oncological data of the included patients were analyzed.

RESULTS

A total of 1690 patients with thyroid cancer were screened. Twenty-four patients were included in the final analysis. The median time to recurrence (95% CI) was 24 months while the Restricted Mean Survival Time (RMST) at time point 24 months (95% CI) was 16.95. The median time to distant metastasis is 60 months while RMST at time point 24 months was 17.1. The median time to death was 55 months. There was a statistically significant difference in the RMST at 24 months for overall survival (OS) as regards older age, presence of comorbidity, multifocality, and lack of adjuvant RAI, but not sex. Male sex and lack of adjuvant RAI therapy were statistically significant independent predictors of the time to locoregional recurrence. There was no statistically significant difference in the time to distant metastasis as regards all the variables.

CONCLUSIONS

From our results, we can conclude that male sex, multifocality, and lack of RAI affect survival in patients with insular thyroid carcinoma. Adequate surgical resection of the thyroid gland and draining lymph nodes in addition to radioactive iodine remains the mainstay of treatment.

Targeted Variant Assessments of Human Endogenous Retroviral Regions in Whole Genome Sequencing Data Reveal Retroviral Variants Associated with Papillary Thyroid Cancer

Papillary thyroid cancer (PTC) is one of the fastest-growing cancers worldwide, lacking established causal factors or validated early diagnostics. Human endogenous retroviruses (HERVs), comprising 8% of human genomes, have potential as PTC biomarkers due to their comparably high baseline expression in healthy thyroid tissues, indicating homeostatic roles. However, HERV regions are often overlooked in genome-wide association studies because of their highly repetitive nature, low sequence coverage, and decreased sequencing quality. Using targeted whole-genome sequence analysis in conjunction with high sequencing depth to overcome methodological limitations, we identified associations of specific HERV variants with PTC. Analyzing WGS data from 138 patients with PTC generated through The Cancer Genome Atlas project and 2015 control samples from the 1000 Genomes Project, we examined the mutational variation in HERVs within a 20 kb radius of known cancer predisposition genes (CPGs) differentially expressed in PTC. We discovered 15 common and 13 rare germline HERV variants near or within 20 CPGs that distinguish patients with PTC from healthy controls. We identified intragenic-intronic HERV variants within RYR2, LRP1B, FN1, MET, TCRVB, UNC5D, TRPM3, CNTN5, CD70, RYR1, RUNX1, CRLF2, and PCDH1X, and three variants downstream of SERPINA1 and RUNX1T1. Sanger sequencing analyses of 20 thyroid and 5 non-thyroid cancer cell lines confirmed associations with PTC, particularly for MSTA HERV-L variant rs200077102 within the FN1 gene and HERV-L MLT1A LTR variant rs78588384 within the CNTN5 gene. Variant rs78588384, in particular, was shown in our analyses to be located within a POL2 binding site regulating an alternative transcript of CNTN5. In addition, we identified 16 variants that modified the poly(A) region in Alu elements, potentially altering the potential to retrotranspose. In conclusion, this study serves as a proof-of-concept for targeted variant analysis of HERV regions and establishes a basis for further exploration of HERVs in thyroid cancer development.

Clinical characteristics and prognostic nomogram for patients with insular thyroid carcinoma: a population-based analysis

BACKGROUND

Insular thyroid carcinoma (ITC) is an uncommon poorly differentiated thyroid malignancy. Due to its rarity, its demographic and clinicopathological features and survival remains unclear. The present study aimed to describe the features and survival of ITC, determine its prognostic factors, and establish a prognostic nomogram.

METHODS

Patients with ITC were identified in the Surveillance, Epidemiology, and End Results database from 2004 to 2019. The features and survival of patients with ITC and other thyroid carcinomas were compared after balancing the baseline characteristics using propensity score matching (PSM). Univariate and multivariate Cox analyses were used to identify the prognostic factors for ITC. Moreover, overall survival (OS)- or cancer-specific survival (CSS)-specific nomograms were established to predict ITC prognosis.

RESULTS

A total of 206 patients with ITCs were identified. The 1-, 2-, 5-, and 10-year OS rates of 206 patients with ITC were 90.3%, 82.0%, 62.2%, and 42.5%, respectively. The median OS was 93 months (95% CI, 73.0-140.0), while the median CSS was 141 months (95% CI, 93.0-173.0). After PSM analysis, the survival analysis of the matched cohort revealed that ITC had a worse clinical outcome than papillary thyroid cancer and follicular thyroid cancer, and better survival than anaplastic thyroid carcinoma. Multivariate Cox regression analysis demonstrated that age, N stage, M stage, and surgery were independent prognostic factors for both OS and CSS in ITC patients. The C-indices for the OS- and CSS-specific nomograms were 0.778 (95% CI, 0.724-0.832) and 0.808 (95% CI, 0.754-0.862), respectively. The calibration curve and ROC analysis indicated that the nomogram models exhibited a good discriminative ability. Decision curve analysis suggested that the nomogram models had a significant positive net benefit and were better than the traditional TNM staging system at predicting survival.

CONCLUSION

ITC has distinct clinicopathological characteristics and survival compared to other thyroid carcinomas, and the established nomogram could predict the survival probability of patients with ITC accurately with a higher net benefit.

Insular thyroid carcinoma in a young Moroccan man: Case report and review of the literature

Introduction

Insular thyroid carcinoma (ITC) was defined as a rare malignant thyroid cancer standing in an intermediate position between the well-differentiated (papillary and follicular) and the anaplastic thyroid carcinomas. The incidence was estimated around <1% and 10% worldwide. Despite its rarity, it remains the main cause of death from non-anaplastic follicular cell-derived thyroid cancers.

Case presentation

A 27-year-old single male admitted for a history of a thyroid nodule and intrathoracic extension; with local mass effect, deviating the brachiocephalic trunk to the right. He underwent a total thyroidectomy. Histopathological examination showed a poorly differentiated insular thyroid carcinoma. Radioactive iodine-131 therapy was administred at a dose of 100 mCi, and the patient was maintained on TSH-suppressive therapy. Ultrasensitive Thyroglobulin measurement after thyroxine withdrawal, taken 2 years after radioactive iodine treatment was undetectable as well as thyroid antithyroglobulin antibodies.

Conclusion

Our clinical case would enrich the global registry of insular thyroid carcinomas’ cases. The main challenge is early detection, aggressive intervention, and close follow-up of affected patients. The advancement in ultra-deep sequencing technologies, will contribute in the development of novel targeted therapies aiming to reduce morbidity and mortality and improve the outcomes in PDTC patients as well.

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Poorly differentiated thyroid carcinomas are defined according to insular growth features, increased mitotic rate, and aggressive clinical behavior.

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Insular thyroid carcinoma is the main cause of death from non-anaplastic follicular cell-derived thyroid cancers.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Treating Clinically Node-Negative Insular Thyroid Carcinoma without Prophylactic Central Compartment Neck Dissection Is Associated with Decreased Survival Regardless of T Staging and Administration of Radioactive Iodine Therapy: The First Evidence

For the rare but aggressive insular thyroid carcinoma (ITC), there's no clear evidence to determine whether prophylactic central compartment neck dissection (CCND) is necessary for cN0 disease. This study provides the first evidence that treating cN0 ITC without prophylactic CCND is associated with decreased survival regardless of T staging and administration of RAI therapy. Background. Regarding the rare but aggressive insular thyroid carcinoma (ITC), the value of prophylactic central compartment neck dissection (CCND) for clinically node-negative (cN0) disease is unclear. We aimed to provide the first evidence. Methods. N0 and pN1a ITC patients were identified from the Surveillance, Epidemiology, and End Results database. These patients were divided into thyroid-surgery + CCND group (pN0/pN1a patients confirmed by CCND) and thyroid-surgery group (cN0 patients without CCND). Differences in overall survival (OS) and disease-specific survival (DSS) between the two groups were evaluated. Subgroup analyses were also conducted. Results. Of the overall 112 patients, 44 (39.3%) received CCND. On multivariate analyses, the lobectomy ± isthmusectomy/total-thyroidectomy (Lob/TT) group demonstrated poorer OS and DSS than the Lob/TT + CCND group (P < 0.05). When we separately analyzed patients treated by TT, multivariate analyses showed the TT group still revealed compromised OS and DSS than the TT + CCND group (P < 0.05). Furthermore, absence of CCND independently predicted decreased OS no matter whether radioactive iodine (RAI) was administered. Similar results were obtained for T3/T4 patients. Moreover, for T1/T2 patients receiving CCND, 0/12 died during the study period, while for T1/T2 patients without CCND, 8/23 (34.8%) died, 5/23 (21.7%) due to ITC. Conclusion. Regardless of T staging and RAI treatment, cN0-ITC patients without CCND had decreased survival compared with pN0/pN1a patients receiving CCND. Therefore, if a cN0 patient is diagnosed with ITC, prophylactic CCND may be considered as a secondary procedure (postoperatively diagnosed) or a primary procedure (preoperatively/intraoperatively diagnosed). Prospective studies are expected to validate the conclusion.

Propensity score matching analysis of the prognosis for the rare insular subtype of thyroid cancer based on SEER database

Insular thyroid carcinoma (ITC) is an uncommon thyroid malignancy with an unclear prognosis. The aim of this study was to determine the prognoses of patients with ITC. We investigated a large cohort of patients with differentiated thyroid cancer from the Surveillance, Epidemiology, and End Results (SEER) database who were registered between 2004 and 2013, and compared the prognosis of patients with ITC to those with classic papillary thyroid cancer (CPTC) and follicular thyroid cancer (FTC). Patient mortality was determined using Kaplan-Meier analyses with log-rank tests, as well as Cox proportional hazards regression analyses. The study cohort comprised of 165 patients with ITC, 5419 patients with FTC, and 60739 patients with CPTC. The rate of cancer-specific mortality per 1000 person-years for ITC was higher than that for CPTC or FTC. According to multivariate Cox regression analysis, however, the cancer-specific and all-cause mortality rates of ITC were similar to those of CPTC and FTC. The cancer-specific survival rate in patients with ITC was higher than that in patients with CPTC, but similar to that in patients with FTC, after adjusting for potentially influencing factors using propensity score matching analysis. These findings, which contrast with previously published data, provide new implications for the treatment of patients with ITC.

Invasive Insular Thyroid Carcinoma Presenting as Nonparalytic Dysphonia

BACKGROUND

Patients with suspected thyroid malignancy often undergo preoperative laryngeal examination with a focus on vocal fold mobility. We present the unique case of a patient with invasive thyroid carcinoma who presented with dysphonia despite intact vocal fold motion.

CASE REPORT

A 73-year-old female with a remote thyroid lobectomy presented with dysphonia. Thyroid ultrasound and fine-needle aspiration revealed a 1.1-cm nodule consistent with a colloid cyst. Videostroboscopy demonstrated mild laryngeal stenosis at the glottis and infraglottis with no evidence of paralysis. After failed medical therapy, the patient underwent microlaryngoscopy with biopsy of her infraglottic fullness, with histopathology reporting squamous epithelium without nucelar atypia. After several weeks of worsening dysphonia and persistent infraglottic fullness, she underwent repeat microlaryngoscopy with biopsy. On postoperative day 1, she developed dyspnea and stridor refractory to maximal medical management. To secure the airway, she underwent an awake tracheostomy, during which the thyroid isthmus was found to be densely adherent to the larynx. Histopathology identified insular thyroid carcinoma. Subsequent imaging confirmed a large, invasive thyroid tumor. Further workup revealed metastases to the bone and liver. The patient underwent a successful palliative resection of the thyroid followed by neck radiation and received palliative spinal surgery with adjuvant radiation. A clinical trial of vandetanib was initiated but withdrawn because of myelosuppression. She deferred any further treatment and was alive with few symptoms despite persistent disease 1.5 years after initial diagnosis.

CONCLUSION

Physicians should consider the diagnosis of invasive thyroid carcinoma in a dysphonic patient with an infiltrative endolaryngeal process despite intact vocal fold mobility.

Radiation therapy dose is associated with improved survival for unresected anaplastic thyroid carcinoma: Outcomes from the National Cancer Data Base

BACKGROUND

The outcomes of patients with unresected anaplastic thyroid carcinoma (ATC) from the National Cancer Data Base (NCDB) were assessed, and potential correlations were explored between radiation therapy (RT) dose and overall survival (OS).

METHODS

The study cohort was comprised of patients who underwent either no surgery or grossly incomplete resection. Correlates of OS were explored using univariate analysis and multivariable analysis (MVA).

RESULTS

In total, 1288 patients were analyzed. The mean patient age was 70.2 years, 59.7% of patients were women, and 47.6% received neck RT. The median OS was 2.27 months, and 11% of patients remained alive at 1 year. A positive RT dose-survival correlation was observed for the entire study cohort, for those who received systemic therapy, and for those with stage IVA/IVB and IVC disease. On MVA, older age (hazard ratio [HR], 1.317; 95% confidence interval [CI], 1.137-1.526), ≥ 1 comorbidity (HR, 1.587; 95% CI, 1.379-1.827), distant metastasis (HR, 1.385; 95% CI, 1.216-1.578), receipt of systemic therapy (HR, 0.637; 95% CI, 0.547-0.742), and receipt of RT compared with no RT (<45 grays [Gy]:HR, 0.843; 95% CI, 0.718-0.988; 45-59.9 Gy: HR, 0.596; 95% CI, 0.479-0.743; 60-75 Gy: HR, 0.419; 95% CI, 0.339-0.517) correlated with OS. The RT dose-survival correlation for patients who received higher (60-75 Gy) versus lower (45-59.9 Gy) therapeutic doses was confirmed by propensity-score matching.

CONCLUSIONS

Survival was poor in this cohort of patients with unresected ATC, and more effective therapies are needed. However, the association of RT dose with OS highlights the importance of identifying patients with unresected ATC who may still yet benefit from multimodal locoregional treatment that incorporates higher dose RT. Cancer 2017;123:1653-1661. © 2017 American Cancer Society.

Malignant struma ovarii with insular carcinoma: A case report and literature review

Image 1 CT image demonstrating the large pelvic mass. Note the sigmoid colon sandwiched between the sacrum and the pelvic mass.Image 1.