Patients with familial non-medullary thyroid cancer have an outcome similar to that of patients with sporadic papillary thyroid tumors

Comparison of Progression-Free Survival in Familial Non-Medullary Thyroid Cancer and Sporadic Differentiated Thyroid Cancer Patients

Background: Familial non-medullary thyroid carcinoma (FNMTC) accounts for approximately 9% of differentiated thyroid cancer (DTC). There is conflicting data on the FNMTC aggressiveness compared with sporadic DTC (sDTC), leading to usually more extensive therapy applied for FNMTC, given its autosomal dominant genetic background. This study aimed to compare the progression-free survival (PFS) in patients with FNMTC and sDTC treated with standard therapy. Methods: This longitudinal retrospective cohort study included patients with FNMTC, defined as at least two first-degree relatives affected by DTC. FNMTC patients were matched with sDTC in a 1:3 ratio based on age, sex, American Thyroid Association recurrence risk stratification (ATA-R), extent of initial surgery, and diagnosis date. The primary outcome was PFS. Kaplan-Meier curves were used to compare PFS between the groups, and the Cox proportional hazards model was used to assess confounders. Results: From 95 affected FNMTC patients, 30 were excluded due to lack of follow-up data. The study population consisted of 65 FNMTC and 170 sDTC patients, with a median follow-up of 4.73 (2.87-10.27) years for FNMTC and 5.83 (2.33-10.79) years for sDTC (p = 0.76). There was 100% matching for ATA-R, sex, surgery type, and year of surgery and a satisfactory matching for age (43.12 ± 15.11 vs. 42.76 ± 12.46 years, p = 0.85). FNMTC exhibited a smaller tumor size (1.20 ± 0.96 vs. 1.89 ± 1.51 cm, p < 0.01) and fewer positive lymph nodes (range 0-13 vs. 0-38, p = 0.009) at presentation. The rate of repeated neck surgeries for persistent/recurrent disease was comparable between the groups: 13.8% (9/65) for FNMTC vs. 17.7% (30/170) for sDTC (p = 0.48). There was no difference in radioactive iodine (RAI) therapy dosage between the groups (104 [100-149] vs. 106 [76-160] mCi, p = 0.82). During follow-up, 15.4% of FNMTC and 18.2% of sDTC patients experienced disease progression (p = 0.61). PFS was non-different between groups (p = 0.56) and was associated with ATA-R (high vs. low hazard ratio [HR]: 9.2, confidence interval [CI]: 2.67-31.85, p < 0.001) and sex (male vs. female, HR: 2.5, CI: 1.11-5.6, p = 0.026). Conclusions: No difference in PFS between FNMTC and sDTC patients suggests comparable responsiveness to standard therapy. Therefore, the management of FNMTC should align with the standard of care for DTC to avoid overtreatment of FNMTC.

Family history of malignant or benign thyroid tumors: implications for surgical procedure management and disease-free survival

Background

Current guidelines lack a standardized management for patients with family history of thyroid carcinoma (fTC),particularly benign thyroid neoplasm (fBTN). Our objective was to investigate the influence of various family histories on the selection of surgical approaches and disease-free survival (DFS).

Methods

A cohort study was conducted involving 2261 patients diagnosed with differentiated thyroid carcinoma including those with fTC (n=224), fBTN (n=122), and individuals without a family history of thyroid carcinoma (nfTC; n=1915). Clinicopathological characteristics were collected. DFS was estimated using Kaplan-Meier analysis and factors affecting DFS were identified using Cox proportional hazard model.

Results

Compared to nfTC, small tumor size, clinically lymph node-positive, extrathyroidal extension, vascular invasion, Hashimoto's disease and nodular goiter were more common in fTC and fBTN groups. They had lower T stage and a lower rate of good response to TSH suppression therapy but received more radioiodine therapy. It is worth noting that fTC is associated with male, bilateral and multifocal tumors, as well as central lymph node metastasis and distant metastasis. Both fTC (aHR = 2.45, 95% CI=1.11-5.38; P = 0.03) and fBTN (aHR = 3.43, 95% CI=1.27-9.29; P = 0.02) were independent predictors of DFS in patients who underwent lobectomy, but not total thyroidectomy. For 1-4 cm thyroid carcinomas with clinically node-negative, fTC was identified as an independent predictor, whereas fBTN was not.

Conclusion

Our findings indicate that a family history, particularly of malignancy, is associated with a more aggressive disease. Family history does not affect the prognosis of patients who undergo total thyroidectomy, but it may increase the risk of postoperative malignant events in those who have a lobectomy. Additionally, it may be necessary to monitor individuals with a family history of benign thyroid neoplasms.

Genetic susceptibility to hereditary non-medullary thyroid cancer

Non-medullary thyroid cancer (NMTC) is the most common type of thyroid cancer. With the increasing incidence of NMTC in recent years, the familial form of the disease has also become more common than previously reported, accounting for 5-15% of NMTC cases. Familial NMTC is further classified as non-syndromic and the less common syndromic FNMTC. Although syndromic NMTC has well-known genetic risk factors, the gene(s) responsible for the vast majority of non-syndromic FNMTC cases are yet to be identified. To date, several candidate genes have been identified as susceptibility genes in hereditary NMTC. This review summarizes genetic predisposition to non-medullary thyroid cancer and expands on the role of genetic variants in thyroid cancer tumorigenesis and the level of penetrance of NMTC-susceptibility genes.

Papillary Thyroid Cancer Affecting Multiple Family Members: A Case Report and Literature Review of Familial Nonmedullary Thyroid Cancer

Familial nonmedullary thyroid cancer (FNMTC) represents 5–10% of NMTC cases. Many controversies are associated with the FNMTC, namely, the minimum required number of affected family members to define the condition, aggressiveness, prognosis, and treatment and screening recommendations. Moreover, the genetic basis of the FNMTC has not yet been identified. We report a family diagnosed with FNMTC and present a comprehensive literature review of the condition. The index case was a 26-year-old male who was diagnosed with locally advanced papillary thyroid cancer (PTC). Then, his family members became worried and asked for a neck ultrasound. Four of his six siblings, in addition to his father, were diagnosed with PTC. In addition, two of his cousins were diagnosed. The patient underwent total thyroidectomy with bilateral neck dissection, and he received 2 doses of radioactive iodine (100 mCi each). Furthermore, one of his siblings required a second surgery with repeated radioactive iodine therapy. The index case genetic screening and whole-exome sequencing did not show any abnormalities. Future genetic and clinical research should focus on kindred with 3 or more affected individuals for better identification of the FNMTC susceptibility genes and to better guide management and screening recommendations.

Familial non-medullary thyroid cancer: a critical review

BACKGROUND

Familial non-medullary thyroid carcinoma (FNMTC), mainly of papillary histotype (FPTC), is defined by the presence of the disease in two or more first-degree relatives in the absence of other known familial syndromes. With the increasing incidence of PTC in the recent years, the familial form of the disease has also become more common than previously reported and constitutes nearly 10% of all thyroid cancers. Many aspects of FNMTC are debated, concerning both clinical and genetic aspects. Several studies reported that, in comparison with sporadic PTCs, FPTCs are more aggressive at disease presentation, while other authors reported no differences in the clinical behavior of sporadic and familial PTCs. For this reason, recent guidelines do not recommend screening of family members of patients with diagnosis of differentiated thyroid cancer (DTC). FNMTC is described as a polygenic disorder associated with multiple low- to moderate-penetrance susceptibility genes and incomplete penetrance. At the moment, the genetic factors contributing to the development of FNMTC remain poorly understood, though many putative genes have been proposed in the recent years.

PURPOSE

Based on current literature and our experience with FNMTC, in this review, we critically discussed the most relevant controversies, including its definition, the genetic background and some clinical aspects as screening and treatment.

Long-Term Clinical Outcome in Familial and Sporadic Papillary Thyroid Carcinoma

BACKGROUND

The definition and the behaviour of familial papillary thyroid cancer (FPTC) compared to the sporadic form (SPTC) are still debated. Some authors believe that only families with 3 or more affected members represent an actual example of familial diseases.

OBJECTIVES

The objective of the study was to analyse the clinicopathological features and the outcome of sporadic and familial PTC patients also according to the number of affected members.

METHODS

Among 731 patients, we identified 101 (13.8%) with familial diseases, 79 with 2 affected members (FPTC-2) and 22 with 3 or more affected members (FPTC-3) followed for a mean period of 10 years.

RESULTS

FPTC patients had more frequently bilateral tumour (p = 0.007). No difference was found between the 2 groups for the other evaluated variables. At the time of the first follow-up (1-2 years after initial therapy), FPTC patients had a higher rate of persistent disease. However, at the last follow-up, the clinical outcome was not different between sporadic and familial patients. When the comparison between SPTC and FPTC was performed, according to the number of affected members, a significant trend between the 3 groups was observed for tumour diameter (p = 0.002) and bilaterality (p = 0.003), while we did not observe a significant trend for both response to initial therapy (p = 0.15) and last clinical outcome (p = 0.22).

CONCLUSIONS

Our results suggest that, although the clinicopathological features of FPTC may be more aggressive, the long-term outcome is similar between FPTC and SPTC. A possible explanation is that PTC has a favourable prognosis, even when clinical presentation is more aggressive.

An update on familial nonmedullary thyroid cancer

Familial nonmedullary thyroid cancer (FNMTC) constitutes 3-9% of all thyroid cancer cases. FNMTC is divided into two groups: syndromic and nonsyndromic. Nonsyndromic FNMTC is more common as compared with syndromic FNMTC. In syndromic FNMTC, patients are at risk of nonmedullary thyroid cancer (NMTC) and other tumors, and the susceptibility genes are known. In nonsyndromic FNMTC, NMTC is the major feature of the disease and occurs in isolation with an autosomal dominant pattern of inheritance and variable penetrance. New data have emerged on the genetics, clinical characteristics, and outcomes of patients with FNMTC that may have clinical relevance in the management of patients. In this review, we focus on newly characterized syndromic FNMTC entities, criteria for screening and surveillance of nonsyndromic FNMTC, and the classification of nonsyndromic FNMTC as well as the genetic background and heterogeneity of nonsyndromic FNMTC.

Should familial disease be considered as a negative prognostic factor in micropapillary thyroid carcinoma?

PURPOSE

An increased aggressiveness of familial papillary thyroid carcinoma (FPTC) compared with sporadic form has been reported. On the contrary, the biological behavior of familial microPTC (FmPTC) is still debated. To assess if familial diseases should be considered as a negative prognostic factor in mPTC, the clinical presentation and outcome of FmPTC and sporadic mPTC (SmPTC) were compared.

METHODS

We retrospectively analyzed 291 mPTC (SmPTC n = 248, FmPTC n = 43) patients followed for a median follow-up of 8.3 years. FmPTC was defined as the presence of PTC in two or more first-degree relatives, after excluding hereditary syndromes associated with PTC.

RESULTS

FmPTC patients had more frequently bilateral tumor (32.6% versus 16.5%, p = 0.01) and lymph node metastases at diagnosis (30.2% versus 14.9%, p = 0.02). At the first follow-up, FmPTC patients had a higher rate of structural disease and a lower rate of remission compared to SmPTC (p = 0.01). Also in a multivariate model, using a "CHAID tree-building algorithm", familial disease correlated with a worse clinical presentation and outcome of mPTC patients. Familial disease was associated with a higher rate of intermediate risk patients in non incidental mPTC and with a higher rate of structural incomplete response in mPTC without lymph node metastases (p = 0.01).

CONCLUSIONS

Like in macroPTC, the familial form of the diseases has been shown to be a negative prognostic factor also in mPTC, therefore, it should be highly regarded in the management of mPTC patients.

Current Knowledge of Germline Genetic Risk Factors for the Development of Non-Medullary Thyroid Cancer

The thyroid is the most common site of endocrine cancer. One type of thyroid cancer, non-medullary thyroid cancer (NMTC), develops from follicular cells and represents approximately 90% of all thyroid cancers. Approximately 5%–15% of NMTC cases are thought to be of familial origin (FNMTC), which is defined as the occurrence of the disease in three or more first-degree relatives of the patient. It is often divided into two groups: Syndrome-associated and non-syndromic. The associated syndromes include Cowden syndrome, familial adenomatous polyposis, Gardner syndrome, Carney complex and Werner syndrome. The hereditary factors contributing to the unfavorable course of FNMTC remain poorly understood; therefore, considerable effort is being expended to identify contributing loci. Research carried out to date identifies fourteen genes (DICER1, FOXE1, PTCSC2, MYH9, SRGAP1, HABP2, BRCA1, CHEK2, ATM, RASAL1, SRRM2, XRCC1, TITF-1/NKX2.1, PTCSC3) associated with vulnerability to FNMTC that are not related to hereditary syndromes. In this review, we summarize FNMTC studies to date, and provide information on genes involved in the development of non-syndromic familial non-medullary thyroid cancers, and the significance of mutations in these genes as risk factors. Moreover, we discuss whether the genetic polymorphism rs966423 in DIRC3 has any potential as a prognostic factor of papillary thyroid cancer.

Do patients with familial nonmedullary thyroid cancer present with more aggressive disease? Implications for initial surgical treatment

BACKGROUND

There are conflicting reports on whether familial nonmedullary thyroid cancer is more aggressive than sporadic nonmedullary thyroid cancer. Our aim was to determine if the clinical and pathologic characteristics of familial nonmedullary thyroid cancer are different than nonmedullary thyroid cancer.

METHODS

We compared patients with familial nonmedullary thyroid cancer to a cohort of 53,571 nonmedullary thyroid cancer patients from the Surveillance, Epidemiology, and End Results database.

RESULTS

A total of 78 patients with familial nonmedullary thyroid cancer from 31 kindreds presented at a younger age (P = .04) and had a greater rate of T1 disease (P = .019), lymph node metastasis (P = .002), and the classic variant of papillary thyroid cancer on histology (P < .001) compared with the Surveillance, Epidemiology, and End Results cohort. Patients with ≥3 affected family members presented at a younger age (P = .04), had a lesser female-to-male ratio (P = .04), and had a greater rate of lymph node metastasis (P = .009). Compared with the Surveillance, Epidemiology, and End Results cohort, we found a higher prevalence of lymph node metastasis in familial nonmedullary thyroid cancer index cases (P = .003) but not in those diagnosed by screening ultrasonography (P = .58).

CONCLUSION

Patients with familial nonmedullary thyroid cancer present at a younger age and have a greater rate of lymph node metastasis. The treatment for familial nonmedullary thyroid cancer should be more aggressive in patients who present clinically and in those who have ≥3 first-degree relatives affected.

Results of Screening in Familial Non-Medullary Thyroid Cancer

BACKGROUND

Although a family history of thyroid cancer is one of the main risk factors for thyroid cancer, the benefit of screening individuals with a family history of thyroid cancer is not known.

METHODS

A prospective cohort study was performed with yearly screening using neck ultrasound and fine-needle aspiration biopsy of thyroid nodule(s) >0.5 cm in at-risk individuals whose relatives were diagnosed with familial non-medullary thyroid cancer (FNMTC). The eligibility criteria were the presence of thyroid cancer in two or more first-degree relatives and being older than seven years of age. Twenty-five kindred were enrolled in the study (12 families with two members affected, and 13 with three or more members affected at enrollment).

RESULTS

Thyroid cancer was detected by screening in 4.6% (2/43) of at-risk individuals from families with two members affected, and in 22.7% (15/66) of at-risk members from families with three or more patients affected (p = 0.01). FNMTC detected by screening was characterized by a smaller tumor size (0.7 ± 0.5 cm vs. 1.5 ± 1.1 cm; p = 0.006), a lower rate of central neck lymph node metastases (17.6% vs. 51.1%; p = 0.02), less extensive surgery (hemithyroidectomy 23.5% vs. 0%; p = 0.002), and a lower rate of radioactive iodine therapy (23.5% vs. 79%; p < 0.001) compared to those affected at enrollment.

CONCLUSIONS

Screening of at-risk family members resulted in earlier detection of low-risk FNMTC and was associated with a less aggressive initial treatment. Screening with thyroid ultrasound should be considered in kindred with three or more family members affected by FNMTC. Since active screening might be associated with the risk of overtreatment, it should be implemented with caution, specifically in elderly individuals.

Should a family history of papillary thyroid carcinoma indicate more aggressive therapy in patients with this tumor?

OBJECTIVE

To determine whether the currently recommended therapy for papillary thyroid carcinoma (PTC) that show no classical factors indicating a poor prognosis is also effective in cases with a family history of this tumor.

SUBJECTS AND METHODS

Forty-two patients were studied; 10 were submitted to lobectomy and 32 to total thyroidectomy, including 23 without lymph node dissection and 9 with lymph node dissection. None of the patients received radioiodine or was maintained under TSH suppression.

RESULTS

No case of recurrence was detected by imaging methods and there was no increase in thyroglobulin or antithyroglobulin antibodies during follow-up (24 to 72 months).

CONCLUSION

The treatment usually recommended for patients with PTC does not need to be modified in the presence of a family history of this tumor if no factors indicating a poor prognosis are present (tumor ≤2 cm, non-aggressive histology, no extensive extrathyroid invasion or important lymph node involvement, complete tumor resection, no evidence of persistent disease after surgery).