Follicular and Hürthle cell carcinoma of the thyroid gland

Radioactive iodine therapy improves overall survival outcome in oncocytic carcinoma of the thyroid by reducing death risks from noncancer causes: A competing risk analysis of 4641 patients

BACKGROUND

Oncocytic carcinoma of the thyroid (OCA) is an independent type of thyroid cancer. Radioactive iodine (RAI) therapy was frequently administered to OCA patients, but its contribution to improving survival is indefinite.

METHODS

4641 OCA patients from 2000 to 2018 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazard regression and competing risk analysis were applied.

RESULTS

Tumor size, SEER stage, primary surgery, and neck dissection were prognostic factors for cancer-specific survival. The results of competing risk analysis demonstrated that age over 55 years dramatically increased non-OCA death risks. Treatments that improve non-OCA survival (including total thyroidectomy, RAI therapy, and systemic therapy) should be recommended in OCA patients older than 55 years of age. Neck lymphadenectomy should not be recommended for OCA, since the metastatic lymph node ratio was low (about 3%).

CONCLUSIONS

RAI therapy can improve survival in OCA by reducing noncancer death risks.

Thyroid Carcinoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Differentiated thyroid carcinomas is associated with an excellent prognosis. The treatment of choice for differentiated thyroid carcinoma is surgery, followed by radioactive iodine ablation (iodine-131) in select patients and thyroxine therapy in most patients. Surgery is also the main treatment for medullary thyroid carcinoma, and kinase inhibitors may be appropriate for select patients with recurrent or persistent disease that is not resectable. Anaplastic thyroid carcinoma is almost uniformly lethal, and iodine-131 imaging and radioactive iodine cannot be used. When systemic therapy is indicated, targeted therapy options are preferred. This article describes NCCN recommendations regarding management of medullary thyroid carcinoma and anaplastic thyroid carcinoma, and surgical management of differentiated thyroid carcinoma (papillary, follicular, Hürthle cell carcinoma).

Hürthle Cell Carcinoma: Single Center Analysis and Considerations for Surgical Management Based on the Recent Literature

BACKGROUND

Hürthle cell carcinoma (HCC) of the thyroid is rare. There are contrasting data on its clinical behavior. The aim of this study was to describe clinic-pathological features and outcomes of HCC patients at our institution, in order to adapt our surgical management.

METHODS

We retrospectively studied 51 cases of HCC treated at the interdisciplinary endocrine center of the University Hospital of Cologne, Germany between 2005 and 2020.

RESULTS

Patients median age was 63 years (range 29-78) with 64.7% of cases being female. Primary treatment included surgery and postoperative radioiodine therapy with 3.7 GBq in all patients. Surgery consisted of total thyroidectomy in all cases and additional central lymphadenectomy in 90.2% of cases. The median number of harvested lymph nodes was 11 (range 2-31). Lymph node involvement was found in two (4.3%) pT4a tumors. In all other cases (95.7%), central lymphadenectomy was prophylactic and lymph nodes were free of metastasis in final histopathology. Twelve (23.5%) patients with incomplete biochemical response to primary treatment were diagnosed with structural relapse during the course of disease, for which seven (58.4%) underwent resection of isolated cervical metastasis. Histopathology revealed soft tissue implants in all cases and cervical surgery led to biochemical and radiologic cure in only two (28.5%) cases. Five (41.6%) patients developed metastatic disease, followed by systemic therapy in two patients. Vascular invasion of the primary tumor was significantly associated with relapse (p<0.01).

CONCLUSIONS

Recurrence of HCC was common in this study. Given the low rate of lymph node metastases both in this study and in recent literature and the nature of relapse (soft tissue instead of nodal metastasis), the benefit of routine prophylactic central lymph node dissection for HCC remains unclear, especially in the absence of vascular invasion from the primary tumor.

Clinicopathological Characteristics and Disease-Free Survival in Patients with Hürthle Cell Carcinoma: A Multicenter Cohort Study in South Korea

BACKGROUND

Hürthle cell carcinoma (HCC), a type of thyroid carcinoma, is rare in South Korea, and few studies have investigated its prognosis.

METHODS

This long-term multicenter retrospective cohort study evaluated the clinicopathological features and clinical outcomes in patients with HCC who underwent thyroid surgery between 1996 and 2009.

RESULTS

The mean age of the 97 patients included in the study was 50.3 years, and 26.8% were male. The mean size of the primary tumor was 3.2±1.8 cm, and three (3.1%) patients had distant metastasis at initial diagnosis. Ultrasonographic findings were available for 73 patients; the number of nodules with low-, intermediate-, and high suspicion was 28 (38.4%), 27 (37.0%), and 18 (24.7%), respectively, based on the Korean-Thyroid Imaging Reporting and Data System. Preoperatively, follicular neoplasm (FN) or suspicion for FN accounted for 65.2% of the cases according to the Bethesda category, and 13% had malignancy or suspicious for malignancy. During a median follow-up of 8.5 years, eight (8.2%) patients had persistent/recurrent disease, and none died of HCC. Older age, gross extrathyroidal extension (ETE), and widely invasive types of tumors were significantly associated with distant metastasis (all P<0.01). Gross ETE (hazard ratio [HR], 27.7; 95% confidence interval [CI], 2.2 to 346.4; P=0.01) and widely invasive classification (HR, 6.5; 95% CI, 1.1 to 39.4; P=0.04) were independent risk factors for poor disease-free survival (DFS).

CONCLUSION

The long-term prognosis of HCC is relatively favorable in South Korea from this study, although this is not a nation-wide data, and gross ETE and widely invasive cancer are significant prognostic factors for DFS. The diagnosis of HCC by ultrasonography and cytopathology remains challenging.

Development and Validation of a Diagnostic Nomogram for the Preoperative Differentiation Between Follicular Thyroid Carcinoma and Follicular Thyroid Adenomas

OBJECTIVE

The aim of the study was to construct and validate a nomogram for differentiating follicular thyroid carcinoma (FTC) from follicular thyroid adenoma (FTA).

METHODS

Two hundred patients with pathologically confirmed thyroid follicular neoplasms were retrospectively analyzed. The patients were randomly divided into a training set (n = 140) and validation set (n = 60). Baseline data including demographics, CT (computed tomography) signs, and radiomic features were analyzed. Predictive models were developed and compared to build a nomogram. The predictive effectiveness of it was evaluated by the area under receiver operating characteristic curve (AUC).

RESULTS

The CT model, radiomic model and combination model showed excellent discrimination (AUCs [95% confidence interval] = 0.847 [0.766-0.928], 0.863 [0.746-0.932], 0.913 [0.850-0.975]). The nomogram based on the combination model showed remarkable discrimination in the training and validation sets. The calibration curves suggested good consistency between actual observation and prediction.

CONCLUSIONS

This study proposed a nomogram that can accurately and intuitively predict the malignancy potential of follicular thyroid neoplasms.

Effect of adjuvant radioactive iodine therapy on survival in rare oxyphilic subtype of thyroid cancer (Hürthle cell carcinoma)

Purpose

Radioactive iodine (RAI) is widely used for adjuvant therapy after thyroidectomy, while its value for thyroid cancer has been controversial recently. The primary objectives of this study were to clarify the influence of Radioactive iodine (RAI) on the survival in rare oxyphilic subtype of thyroid cancer (Hürthle cell carcinoma, HCC).

Methods

Patients diagnosed with oxyphilic thyroid carcinoma from 2004 to 2015 were extracted from the Surveillance, Epidemiology, and End Results Program database. The Kaplan-Meier method was used to compare overall survival (OS) and cancer-specific survival (CSS) among patients who had adjuvant RAI use or not. Univariate and multivariate Cox proportional hazard models were performed for survival analysis, and subsequently visualized by nomogram.

Results

In all, 2,799 patients were identified, of which 1529 patients had adjuvant RAI use while 1,270 patients had not. Based on multivariate Cox analysis, the RAI therapy confers an improved OS for HCC patients (HR = 0.57, 95% CI [0.44–0.72], P < 0.001), whereas it has no significant benefit in the survival analysis regarding CSS (HR = 0.79, 95% CI [[0.47–1.34], P = 0.382). In a subgroup analysis, the same survival benefit of RAI treatment on OS, but not CSS was observed among patients stratified by AJCC stage and tumor extension. Nevertheless, patients with regional lymph node metastasis benefited from RAI therapy both in OS and CSS (P < 0.001, respectively). Furthermore, nomograms used for predicting long term survival of HCC patients exhibited a better prediction power for OS compared with traditional tumor, nodal and metastatic (TNM) stage made by American Joint Committee on Cancer (AJCC) (C-index = 0.833 of the nomogram model vs. 0.696 of the AJCC system).

Conclusions

This study suggests that RAI therapy is significantly associated with improved OS in patients with Hürthle cell carcinoma. However, there was no association between treatment with radioiodine and CSS, possibly due to small number of deaths that were related to HCC.

Is Frozen-Section Analysis During Thyroid Operation Useful in the Era of Molecular Testing?

BACKGROUND

With the increased use of molecular testing of thyroid fine-needle biopsies, the frequency and extent of thyroid resection for thyroid nodules has changed. Although the role of frozen-section analysis of the thyroid has been reduced markedly in recent years, many surgeons still routinely use it intraoperatively. We sought to determine the utility of frozen section during thyroidectomy in the era of molecular testing.

STUDY DESIGN

We reviewed 236 consecutive patients who had thyroidectomy with intraoperative frozen-section analysis at our institution between November 2015 and October 2017. We re-reviewed the preoperative diagnosis, frozen-section diagnosis, final pathology, and whether operative management changed from the initial plan based on frozen section.

RESULTS

Mean age of the patients was 55.6 ± 14.1 years, and 83% were female. Of the 236 patients, frozen section did not change the intraoperative management in 225 (95%). Of the 11 patients whose thyroid operation was modified, the operation was either too much or not enough in 6 patients. In only 5 (2.1%) patients, frozen-section analysis correctly changed the extent of thyroidectomy.

CONCLUSIONS

Thyroid frozen-section analysis adds cost and time to thyroid operations without notable benefit. In our cohort, only 2.1% of frozen sections accurately changed intraoperative management. We recommend against its routine use.

Neck Ultrasound in Patients with Follicular Thyroid Carcinoma

There are limited data on the role of neck ultrasound (US) in the surveillance of patients with follicular thyroid cancer (FTC). Here, we analyze the likelihood of US to find structural disease in patients with FTC and evaluate if initial American Thyroid Association (ATA) risk stratification and the response to therapy categories [the latter based on thyroglobulin (Tg) levels] modify that likelihood. We conducted a retrospective cohort study of 32 patients with FTC in our institution. We included all patients with well-differentiated FTC who underwent total thyroidectomy and radioactive iodine (RAI) treatment without neck structural disease at the time of RAI and with Tg and US at least 6 months after RAI. After a median follow-up of 4.3 years, two patients (6.3%) had structural disease by US. None of the 18 patients with initial ATA low-risk disease had structural disease by US in contrast to higher, but not significant, frequency of 18.2% (2/11) in patients with initial ATA high-risk disease (p = 0.14). Based on Tg levels, 24/32 patients had excellent response to therapy and 8/32 had biochemical incomplete/indeterminate response. None of the patients with excellent response had structural disease by US versus 2/8 (25%) patients with biochemical incomplete/indeterminate response all of whom had other sites of structural disease (p = 0.054). Our findings suggest that neck US in FTC is unlikely to find structural disease with initial low-risk ATA or excellent response to therapy but can detect structural disease in some patients with initial ATA high-risk or incomplete/indeterminate responses to therapy.

Radioactive Iodine Treatment Is Associated with Improved Survival for Patients with Hürthle Cell Carcinoma

BACKGROUND

Hürthle cell carcinoma (HCC) is not typically iodine avid, raising questions regarding postoperative use of radioactive iodine (RAI). The aims of this study were to describe current practice patterns regarding the use of RAI for HCC and to assess its association with survival.

METHODS

The National Cancer Data Base 1998-2006 was queried for all patients with HCC who underwent total thyroidectomy. Inclusion was limited to T1 tumors with N1/M1 disease, and T2-4 tumors with any N/M disease. Patients were divided into two treatment groups based on receipt of RAI. Baseline patient characteristics were compared between the two groups. Survival was examined using Kaplan-Meier and Cox regression analyses.

RESULTS

A total of 1909 patients were included. Of these, 1162 (60.9%) received RAI, and 747 (39.1%) did not. Patients treated with RAI were younger (57 vs. 61 years for no RAI, p < 0.001), more often had private insurance (61.7% vs. 53.5% for no RAI, p < 0.003), and were more likely to be treated at an academic center (40.0% vs. 33.1% for no RAI, p < 0.001). Five- and 10-year survival rates were improved for patients who received RAI compared with those who did not (88.9 vs. 83.1% and 74.4 vs. 65.0%, respectively, p < 0.001). RAI administration was associated with a 30% reduction in mortality (hazard ratio = 0.703, p = 0.001).

CONCLUSION

Present guidelines are inconsistent with regard to indications for using RAI for HCC. This could explain why nearly 40% of HCC patients did not receive RAI. RAI is associated with improved survival, suggesting that it should be advocated for HCC patients with tumors >2 cm and those with nodal and distant metastatic disease.

Follicular and Hurthle cell carcinoma of the thyroid in iodine-sufficient area: retrospective analysis of Korean multicenter data

BACKGROUND/AIMS

Follicular thyroid carcinoma (FTC) and Hurthle cell carcinoma (HCC) of the thyroid are relatively uncommon thyroid malignancies in iodine-sufficient areas. In this study we evaluated the clinical behavior, prognostic factors and treatment outcomes of FTC and HCC in Korea.

METHODS

This multicenter study included 483 patients with FTC and 80 patients with HCC who underwent an initial surgery between 1995 and 2006 in one of the four tertiary referral hospitals in Korea. We evaluated clinicopathological factors associated with distant metastases and recurrence during a median of 6 years of follow-up.

RESULTS

HCC patients were significantly older (49 years vs. 43 years; p < 0.001) and had more lymphovascular invasions (22% vs. 14%; p = 0.03) compared with FTC patients. Distant metastases were confirmed in 40 patients (8%) in the FTC group and in two patients (3%) in the HCC group (p = 0.07). Distant metastases were significantly associated with older age, widely invasive cancer and extrathyroidal invasion. Only 14 patients (3%) had recurrent disease and there was no significant difference between FTC and HCC groups (p = 0.38). Recurrence was associated with larger tumor size and cervical lymph node metastasis.

CONCLUSIONS

HCC patients were older and had more lymphovascular invasions than FTC patients. However, FTC and HCC patients had similar initial clinicopathological features. Older age, wide invasiveness and extrathyroidal invasion were independent risk factors for predicting distant metastases in FTC and HCC patients.

The surgical management of thyroid cancer

Thyroid cancer has been increasing in incidence, with the number of reported cases in the US rising by 25% over the last 3 years. With growing technological advances in the field and improved contributions of diagnostics, surgical decision-making and operative planning have taken on new challenges. Herein, we review the current clinical practice recommendations and active areas of surgical controversy, reflective of the most recently published professional consensus guidelines and a systematic review of the literature.

Clinicopathological and prognostic analysis of follicular thyroid carcinoma in a single institute over a 15-year period

BACKGROUND

This study was to evaluate the clinicopathological and prognostic features of follicular thyroid carcinoma (FTC) in our institute over a 15-year period.

METHODS

The clinical features, management and outcome of 134 consecutive patients were analyzed according to the time of diagnosis: Group I (1997-2001), Group II (2002-2006), and Group III (2007-2011).

RESULTS

As time advanced, the ratio of FTC to papillary thyroid carcinoma decreased from 8.7% in group I to 4.3% in group III (p = 0.000). The percentage of patients undergoing total thyroidectomy seemed to be more commonly used in the later periods - from 10.5% in group I to 21.8% in group II and 18.9% in group III. The median diameter of tumors in group I was 4.2 cm and it showed a sharp decrease to 2.8 cm in group II and 2.9 cm in group III respectively. There was a trend towards a higher stage in patients from Group I vs. patients from Groups II and III (stage IV, 15.8% vs. 2.2% and 4.3%, p = 0.072). The outcome was improved in terms of disease-free survival (DFS). The 3-year DFS rate improved from 77.8% in group I to 93.7% in group II and 100% in group III (p = 0.008).

CONCLUSIONS

The clinical features, management and outcome of FTC patients changed over 15-year period. Patients diagnosed after 2001 had a better prognosis. This improvement was probably related to earlier diagnosis with smaller tumor size and presentation at earlier tumor stage.

New developments in the diagnosis and treatment of thyroid cancer

Thyroid cancer exists in several forms. Differentiated thyroid cancers include those with papillary and follicular histologies. These tumors exist along a spectrum of differentiation, and their incidence continues to climb. A number of advances in the diagnosis and treatment of differentiated thyroid cancers now exist. These include molecular diagnostics and more advanced strategies for risk stratification. Medullary cancer arises from the parafollicular cells and not the follicular cells. Therefore, diagnosis and treatment differs from those of differentiated thyroid tumors. Genetic testing and newer adjuvant therapies have changed the diagnosis and treatment of medullary thyroid cancer. This review will focus on the epidemiology, diagnosis, workup, and treatment of both differentiated and medullary thyroid cancers, focusing specifically on newer developments in the field.

Hurthle cell carcinoma: a population-level analysis of 3311 patients

BACKGROUND

Hurthle cell carcinoma (HCC) is an uncommon and more aggressive thyroid cancer. To date, there is a paucity of data at a population level. In this study, demographic, clinical, and pathologic characteristics of HCC were investigated and compared with other types of differentiated thyroid cancers (ODTCs). The authors also evaluated disease-specific survival and compliance with American Thyroid Association (ATA) management guidelines from 2009.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database from 1988 to 2009 was used to obtain data on patients with thyroid cancer. Data analyses were performed using chi-square tests, analysis of variance, Kaplan-Meier analysis, binary logistic regression, and Cox proportional hazards regression.

RESULTS

In total, 3311 patients with HCC and 59,585 patients with ODTC were identified. Compared with ODTC, HCC was more common among men (31.1% vs 23.0% for ODTC; P < .001) and among older patients (mean age, 57.6 years vs 48.9 years for ODTC; P < .001). Patients with HCC presented with higher SEER disease stage (P < .001), and their tumors were larger (36.1 mm vs 20.2 mm for ODTC; P < .001). Fewer patients underwent total thyroidectomy (P = .028). Both overall and disease-specific survival were lower for patients with HCC (P < .001), and neither improved over the last 2 decades (P = .689). After adjustment, age ≥45 years, not undergoing surgery, and metastatic disease were strongly associated with a worse prognosis (hazard ratio >3.0). Compliance with recommended surgical treatment according to ATA guidelines was lower among patients with HCC aged ≥65 years (odds ratio [OR], 1.43; P = .002) and among unmarried patients (OR, 1.29; P = .004). Predictors of noncompliance with ATA guidelines for treatment with radioactive implants or radioisotopes were age ≥65 years (OR, 1.31; P = .017), diagnosis between 1988 and 1997, no surgery, and partial thyroidectomy (OR, 1.81, 19.48, and 4.02, respectively; P < .001).

CONCLUSIONS

HCC has more aggressive behavior and compromised survival compared with ODTC. The current results indicated that it may be important to consider a different staging system or separate practice guidelines.

Thyroid cancer in older men

This article reviews most common types of thyroid cancer focusing on older males worldwide. Thyroid carcinoma is the most common endocrine malignancy. It includes tumour types that range from localised papillary carcinomas to lethal anaplastic disease. Among elderly population, male gender seems to be highly correlated with the risk and aggressiveness of thyroid cancer. Early diagnosis and urgent aggressive treatment are important for aging patients. This article includes numerous studies which evaluate prevalence, morbidity and mortality of thyroid cancer in older males.

Follicular adenoma and carcinoma of the thyroid gland

Follicular neoplasms of the thyroid gland include benign follicular adenoma and follicular carcinoma. Currently, a follicular carcinoma cannot be distinguished from a follicular adenoma based on cytologic, sonographic, or clinical features alone. The pathogenesis of follicular carcinoma may be related to iodine deficiency and various oncogene and/or microRNA activation. Advances in molecular testing for genetic mutations may soon allow for preoperative differentiation of follicular carcinoma from follicular adenoma. Until then, a patient with a follicular neoplasm should undergo a diagnostic thyroid lobectomy and isthmusectomy, which is definitive treatment for a benign follicular adenoma or a minimally invasive follicular cancer. Additional therapy is necessary for invasive follicular carcinoma including completion thyroidectomy, postoperative radioactive iodine ablation, whole body scanning, and thyrotropin suppressive doses of thyroid hormone. Less than 10% of patients with follicular carcinoma will have lymph node metastases, and a compartment-oriented neck dissection is reserved for patients with macroscopic disease. Regular follow-up includes history and physical examination, cervical ultrasound and serum TSH, and thyroglobulin and antithyroglobulin antibody levels. Other imaging studies are reserved for patients with an elevated serum thyroglobulin level and a negative cervical ultrasound. Systemic metastases most commonly involve the lung and bone and less commonly the brain, liver, and skin. Microscopic metastases are treated with high doses of radioactive iodine. Isolated macroscopic metastases can be resected with an improvement in survival. The overall ten-year survival for patients with minimally invasive follicular carcinoma is 98% compared with 80% in patients with invasive follicular carcinoma.

Delayed intrathyroidal hematoma causing respiratory distress after a seemingly benign fall: a case report

A rare event of a fall causing delayed intrathyroidal hematoma and respiratory distress is reported here. A 75-year-old woman with symptoms of vertigo causing syncope and fall 24 h earlier was seen and discharged from our emergency department after an unremarkable physical exam and 6-h observation period. Within 3 h of discharge, the patient was transported back by Emergency Medical Services with an enlarging neck mass and subjective respiratory distress. CT scan demonstrated a large, expanding hematoma, and the patient underwent an emergency hemithyroidectomy. Hürtle cell adenoma was found on pathologic specimen examination. A review of the literature of similar cases is presented, emphasizing the notion that concurrent thyroid pathology is a risk factor for airway compromise after seemingly benign trauma and that airway compromise can present in a delayed fashion.

The impact of lymph node involvement on survival in patients with papillary and follicular thyroid carcinoma

BACKGROUND

The prognostic role of lymph node metastases in well-differentiated thyroid carcinoma remains controversial. We investigated impact of lymph node involvement on survival in patients with well-differentiated thyroid cancer.

METHODS

We queried the Surveillance, Epidemiology, and End Results registry for patients diagnosed with well-differentiated thyroid carcinoma between 1988 and 2003. Cases were stratified by age (<45 vs >/=45 years) and pathology (papillary/follicular). Four separate Cox regression models were developed to test the effects of demographic and clinical covariates on survival.

RESULTS

We identified 33,088 patients. 30,504 patients (49% >/=45 years) had papillary carcinoma and 2,584 patients (55% >/=45 years) had follicular carcinoma. Age affected survival in all models (P < .001). In patients with papillary carcinoma <45 years, lymph node disease did not influence survival (P = .535), whereas in patients >/=45 years, lymph node involvement was associated with 46% increased risk of death (P < .001). In patients with follicular carcinoma, lymph node involvement conferred increased risk of death in both age groups (P </= .002). Effects of other covariates varied between models.

CONCLUSION

Cervical lymph node metastases conferred independent risk in all patients with follicular carcinoma and in those patients with papillary carcinoma aged >/=45 years, but did not affect survival in patients with papillary carcinoma <45 years.