Familial Papillary Thyroid Carcinoma Research Articles

Nonmedullary thyroid carcinoma in kindreds: A case series and review of familial papillary thyroid carcinoma

Nonmedullary thyroid carcinoma in kindreds: A case series and review of familial papillary thyroid carcinoma

Familial papillary thyroid carcinoma as a new clinical entity

Familial papillary thyroid carcinoma as a new clinical entity

RETROSPECTIVE COHORT STUDY: DIFFERENCES AND SIMILARITIES BETWEEN SPORADIC AND FAMILIAL PAPILLARY THYROID CARCINOMA

Abstract INTRODUCTION There is a lot of controversy around the study of the familial papillary thyroid carcinoma (CPFT), which has a different behaviour than sporadic. The aim of this investigation is to establish the differences and similarities between sporadic papillary thyroid carcinoma and the familial one in order to determine if the familial type is a more aggressive clinical entity than sporadic. MATERIAL AND METHODS A retrospective cohort study in 231 patients with papillary thyroid carcinoma (CPT) from 2006 to 2018. One group was established according to the presence of two or more relatives as CPFT (n = 46) and the other group were the sporadic cases (n = 185). Throughout this study the clinical-pathological characteristics of both groups were compared based on the analysis of twenty-one variables. RESULTS After having carried out this investigation, statistically significant differences have only been found in the vascular invasion (p < 0.001), presenting 3.8% in the sporadic group compared to the 21.7% found in the CPFT with an Odds Ratio of 7.6. CONCLUSIONS Based on our experience, patients with CPFT present a higher frequency of multifocal neoplasia, capsular invasion, vascular invasion, lymph node invasion and recurrence than sporadic CPT. However, these differences were only significant while analyzing the vascular invasion variable. Although the results of our study have been unable to prove that the CPFT is more aggressive than sporadic CPT, we recommend performing periodic ultrasounds such as the screening of the members of the families with CPFT. Finally, we conclude that more studies are needed.

Is familial papillary thyroid carcinoma different from sporadic form in terms of clinicopathological features and outcome?

Is familial papillary thyroid carcinoma different from sporadic form in terms of clinicopathological features and outcome?

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.

The clinicopathologic characteristics of familial and sporadic papillary thyroid carcinoma in Turkish patients

Background/aim The aim of this study is to investigate clinicopathologic features of familial papillary thyroid carcinoma (fPTC) and compare them with sporadic papillary thyroid carcinoma (sPTC) in Turkish patients. A retrospective analysis of the papillary thyroid carcinoma (PTC) cases, with or without family history with a follow-up around 10 years was performed. Materials and methodsA series of patients with fPTC (82 fPTC families with 146 affected individuals) were compared with patients with sPTC (n = 112). The clinicopathologic features [(age, gender, histologic subtype, tumour size, bilaterality, multifocality, extrathyroidal extension (ETE), lymph node metastasis (LNM)] and treatment procedures (lymph node dissection, radioactive iodine ablation), and the outcomes like recurrences in the neck region, distant metastasis, and the need for reoperation were compared between the groups.Results When the groups were compared, there was no significant difference in age (P = 0.449), and tumour size (P = 0.898) between familial and sporadic PTC patients. fPTC group had a significantly higher risk of male gender (P=0.001), bilaterality (P = 0.004), multifocality (P = 0.011), LNM (P = 0.013), ETE (P = 0.040), and distant metastasis (P ≤ 0.0001) than the sPTC group. However, recurrence rate was similar between the 2 groups (P = 0.436).Conclusion The results of this study confirms a more aggressive nature in fPTC patients, in terms of bilaterality, multifocality, ETE, LNM, and distant metastasis, compared to sPTC patients in Turkish population.

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

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

Hereditary and familial thyroid tumours.

The worldwide incidence of thyroid malignancies has been increasing rapidly. Sensitive imaging modalities and early detection of thyroid lesions have made thyroid cancers the most rapidly increasing cancers in the USA in 2017 (SEER Cancer Facts, 2017). Clinical awareness of potential risk factors, such as inherited thyroid cancers, has allowed earlier recognition of more vulnerable population clusters. Hereditary thyroid neoplasms arising from calcitonin-producing C cells are known as familial medullary thyroid carcinomas (FMTCs), and include well-documented syndromes such as multiple endocrine neoplasia IIA or IIB, and pure familial medullary thyroid carcinoma syndrome. Familial thyroid cancers arising from follicular cells are referred to as familial non-medullary thyroid carcinoma (FNMTC), or familial follicular cell-derived carcinoma. Clinicopathological correlations have resulted in the further subclassification of FNMTCs into two groups. Among the first group are found syndromes characterised by a predominance of non-thyroidal tumours, including familial adenomatous polyposis, Cowden syndrome, Werner syndrome, Carney complex, and Pendred syndrome. The second group encompasses a spectrum of familial syndromes characterised by a predominance of non-medullary thyroid tumours, such as pure familial papillary thyroid carcinoma with or without oxyphilia, familial papillary thyroid carcinoma with papillary renal cell carcinoma, and familial papillary carcinoma with multinodular goitre. Most familial thyroid cancers have been described as being more aggressive than sporadic thyroid cancers, with a predisposition for lymph node metastasis, extrathyroidal invasion, and a younger age of onset. The distinct thyroid pathology in some of these syndromes should alert the pathologist to a possible familial cancer syndrome.

Abstract 4287: HABP2 p.G534E variant in patients with family history of thyroid and breast cancer

Abstract Background. Familial Papillary Thyroid Carcinoma (PTC) has been recently associated with the HABP2 p.G534E mutation. In this study we evaluated the putative association of the HABP2 p.G534E mutation and familial history of PTC and Breast Carcinoma (BC) in the Brazilian population. Methods. Germline mutations of twenty unrelated individuals with personal and/or family history of PTC and/or BC were identified by whole exome sequencing (WES), using Nextera Exome Enrichment kit and HiSeq200 platform (Illumina). Two cases were positive for p.G534E. Family members from both positive cases (seven from Family 1 and three from Family 2) were recruited for segregation analysis. An additional patient and three relatives (Family 3) with history of PTC and BC were included for validation. Fifty frozen PTC tumor samples and 170 healthy Brazilian individuals were also screened for the HABP2 variant. Confirmation and validation were performed by Sanger sequencing. Results. Interestingly, Family 1 reported a consanguineous history, reflected in two homozygous cases: the proband (PTC) and his unaffected sister. Also, only one (BC) out of eight tested members was negative for p.G534E. In the Family 2, the only patient diagnosed with PTC was negative for the mutation, while three relatives were positive for the same loci. The index case (PTC) from Family 3, was wild type for HABP2 and three relatives tested were positive carriers. In PTC tumor samples the Allele Frequency (AF) was 0.04: two heterozygous and one homozygous for p.G534E. Among 170 healthy individuals, five were heterozygous for the variant, representing an AF of 0.0147. The two index patients evaluated by WES also presented interesting pathogenic variants in genes potentially associated with deregulation of the extracellular matrix organization pathway (CTSB, TNXB, COL4A3, COL16A1, COL24A1, COL5A2, NID1, LOXL2, MMP11, TRIM24 and MUSK) and DNA repair function (NBN and MSH2). Conclusion. Our findings suggest that HABP2 is not a predisposition gene involved in familial PTC and BC. Financial Support: FAPESP (2013/01867-8 and 2014/03983-8) and CNPq (481132/2012-0) Note: This abstract was not presented at the meeting. Citation Format: Maisa Pinheiro, Sandra A. Drigo, Fabio A. Marchi, Renata Tonhosolo, Sonia C. Andrade, Igor Jurisica, Luiz P. Kowalski, Maria Isabel W. Achatz, Silvia R. Rogatto. HABP2 p.G534E variant in patients with family history of thyroid and breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4287. doi:10.1158/1538-7445.AM2017-4287

FAMILIAL PAPILLARY THYROID CARCINOMA: A CASE SERIES

The natural history and inheritance of familial papillary thyroid carcinoma (FPTC) remain unclear. A specific genetic defect responsible for this condition and its inheritance is yet to be established. The penetrance, mode of inheritance and treatment of this familial thyroid condition are different from other familial thyroid conditions (familial medullary thyroid cancer). Presented here is a family of four sisters in which three developed multifocal PTC. A 47-year-old lady presented with incidental finding of multinodular goitre and normal thyroid function. She had three other sisters who were diagnosed with PTC at age 46, 48 and 49 years. Detailed clinical history of her sisters was gathered from them over telephone as they all moved to different parts of world in their twenties. Literature review was carried out to find similar patients reported in literature. Environmental factors were less important in the development of PTC in this family. It was also interesting that all three were diagnosed with the condition at a very similar age. FPTC behaviour was not more aggressive than sporadic form of disease. There is not enough evidence in literature to suggest prophylactic thyroidectomy in relatives of patients with PTC. Since the exact inheritance pattern of this condition is not known, detailed family history is important in patients with thyroid disorders to identify high-risk patients. Genetic factors are much more important than environmental factors in the development of this condition. The first-degree relatives should be assessed clinically for further investigations if two individuals in the same family develop the condition at similar age.Key words: Familial follicular thyroid cancer, familial papillary thyroid cancer, papillary thyroid cancer

HABP2 p.G534E variant in patients with family history of thyroid and breast cancer.

Familial Papillary Thyroid Carcinoma (PTC) has been described as a hereditary predisposition cancer syndrome associated with mutations in candidate genes including HABP2. Two of 20 probands from families with history of PTC and breast carcinoma (BC) were evaluated by whole exome sequencing (WES) revealing HABP2 p.G534E. Sanger sequencing was used to confirm the involvement of this variant in three families (F1: 7 relatives; F2: 3 and F3: 3). The proband and his sister (with no malignant tumor so far) from F1 were homozygous for the variant whereas one relative with PTC from F2 was negative for the variant. Although the proband of the F3 with PTC was HABP2 wild type, three relatives presented the variant. Five of 170 healthy Brazilian individuals with no family history of BC or PTC and three of 50 sporadic PTC presented the p.G534E. These findings suggested no association of this variant with our familial PTC cases. Genes potentially associated with deregulation of the extracellular matrix organization pathway (CTSB, TNXB, COL4A3, COL16A1, COL24A1, COL5A2, NID1, LOXL2, MMP11, TRIM24 and MUSK) and DNA repair function (NBN and MSH2) were detected by WES, suggesting that other cancer-associated genes have pathogenic effects in the risk of familial PTC development.

Multiple HABP2 variants in familial papillary thyroid carcinoma: Contribution of a group of “thyroid-checked” controls

A heterozygous germline variant in the HABP2 gene c.1601G > A (p.Gly534Glu), which negatively impacts its tumor suppressive activity in vitro, has been described in 4–14% of kindreds of European-American ancestry with familial papillary thyroid carcinoma (fPTC). But it is also found in ≈4% of Europeans and European/Americans from public databases that, however, did not provide information on the thyroid function of the controls. To get unbiased results, we decided to compare HABP2 genotypes of patients with fPTC with those of “thyroid-checked” controls. A control group consisting of 136 European patients who were thyroidectomised for medullary thyroid carcinoma and devoid of any histologically detectable PTC or follicular-deriving carcinoma was built. In parallel we recruited 20 patients with fPTC from eleven independent European kindreds. The entire coding region of HABP2 was analyzed by Sanger sequencing the germline DNAs of patients. Nucleotide variants were searched for by Snap Shot analysis in the controls. Two variants, c.1601G > A (p.Gly534Glu) and c.364C > T (p.Arg122Trp), were found in 2 and 3 patients at the heterozygous level respectively (minor allele frequency (MAF): 5.0% and 7.5%, respectively). In controls, the MAF was either similar for the c.1601G > A HABP2 variant (2.94%, ns) or significantly lower for the c.364C > T variant (0.73%, p = 0.016). The Arg122 residue lies in the EGF-3 domain of HABP2 which is important for its activation but, however, superposition of the predicted 3D structures of the wild type and mutated proteins suggests that this variant is tolerated at the protein level. In conclusion, our data do not support the pathogenicity of the HABP2 c.1601G > A variant but highlight the existence of a new one that should be more extensively searched for in fPTC patients and its pathogenicity more carefully evaluated.

Variants in microRNA genes in familial papillary thyroid carcinoma.

Papillary Thyroid Carcinoma (PTC) displays one of the highest familiality scores of all cancers as measured by case-control studies, yet only a handful of genes have been implicated until now. Variants in microRNAs have been associated with the risk of several cancers including PTC but the magnitude of this involvement is unclear. This study was designed to test to what extent genomic variants in microRNAs contribute to PTC risk. We used SOLiD technology to sequence 321 genomic regions encoding 427 miRNAs in one affected individual from each of 80 PTC families. After excluding variants with frequency ≥ 1% in 1000 Genomes Phase 1 (n = 1092) we detected 1978 variants. After further functional filtering steps 25 variants in pre-miRs remained. Co-segregation was observed for six out of 16 tested miRNA variants with PTC in the families, namely let-7e, miR-181b, miR-135a, miR-15b, miR-320, and miR-484. Expression of miR-135a and miR-181b was tested in normal thyroid and tumor tissue from patients that carry the variants and a decrease in expression was observed. In vitro assays were applied to measure the effect of the variants on microRNAs’ maturation. Four out of six variants were tested. Only the let-7e and miR-181b variants showed an effect on processing leading to lower levels of mature miRNA. These two variants were not detected in 1170 sporadic PTC cases nor in 1404 controls. Taken together, our data show that high penetrance germline sequence variants of miRNAs potentially predispose to a fraction of all PTC but are not common.

Familial Papillary Thyroid Carcinoma (FPTC): a Retrospective Analysis in a Sample of the Bulgarian Population for a 10-Year Period.

In recent years, there are numerous reports indicating the presence of familial papillary carcinoma. Unfortunately, no genetic defect can be linked directly to the disease. In this study, we set the goal to make a retrospective analysis of the cases with papillary carcinoma in the Department of Endocrine Surgery for the past 10years, to compare the characteristics of sporadic and familial forms of the disease and to find families with hereditary papillary carcinoma. The study included 810 patients treated for thyroid cancer in the Department of Endocrine Surgery, USBALE "Acad. Iv. Penchev" Hospital, between January 1, 2006 and December 31, 2015. We used chi square test to determine statistical significant difference. The data analysis and interpretation was performed on SPSS 20.0. Both groups had similar demographic distribution. We found that 587 patients have sporadic papillary carcinoma, while 147 have a relative with thyroid pathology in the first degree of kinship. In 8 patients, there was a blood relative with thyroid cancer. When we compared the two groups, we found statistically significant difference only in tumor size. There was no significant difference in aggressiveness of the thyroid cancer (multifocality and lymph node metastasis). When analyzing the results, we identified 147 patients with a family history of thyroid disease (20%). In 8 patients (5.44%), we found at least one relative with papillary thyroid carcinoma. However, our study does not demonstrate any difference in the aggressiveness of familial and sporadic papillary thyroid carcinoma.

Genetic Heterogeneity of HER2 Amplification and Telomere Shortening in Papillary Thyroid Carcinoma.

Extensive research is dedicated to understanding if sporadic and familial papillary thyroid carcinoma are distinct biological entities. We have previously demonstrated that familial papillary thyroid cancer (fPTC) cells exhibit short relative telomere length (RTL) in both blood and tissues and that these features may be associated with chromosome instability. Here, we investigated the frequency of HER2 (Human Epidermal Growth Factor Receptor 2) amplification, and other recently reported genetic alterations in sporadic PTC (sPTC) and fPTC, and assessed correlations with RTL and BRAF mutational status. We analyzed HER2 gene amplification and the integrity of ALK, ETV6, RET, and BRAF genes by fluorescence in situ hybridization in isolated nuclei and paraffin-embedded formalin-fixed sections of 13 fPTC and 18 sPTC patients. We analyzed BRAFV600E mutation and RTL by qRT-PCR. Significant HER2 amplification (p = 0.0076), which was restricted to scattered groups of cells, was found in fPTC samples. HER2 amplification in fPTCs was invariably associated with BRAFV600E mutation. RTL was shorter in fPTCs than sPTCs (p < 0.001). No rearrangements of other tested genes were observed. These findings suggest that the association of HER2 amplification with BRAFV600E mutation and telomere shortening may represent a marker of tumor aggressiveness, and, in refractory thyroid cancer, may warrant exploration as a site for targeted therapy.

Multiple HABP2 variants in familial papillary thyroid carcinoma: A case-control study

Objective A heterozygous germline variant in the HABP2 gene (p.G534E), that negatively impacts its tumor suppressive activity in vitro, has been described in 4 to 14% of kindreds of European ancestry with familial papillary thyroid carcinoma (fPTC). But it is also found in ≈4% of Europeans and European Americans from public databases that, however, did not provide information on the thyroid function of the controls. To get unbiased results, we decided to compare genotypes of patients with fPTC with those of “thyroid-checked” controls. Materials and methods We built a control group consisting of 95 European patients who underwent a thyroidectomy for medullary thyroid carcinoma and were devoid of any histologically detectable PTC or follicular-deriving carcinoma. In parallel we recruited 17 patients with fPTC from nine independent European kindreds. The entire coding region of HABP2 was analyzed by Sanger sequencing the germline DNAs of patients. Results Two variants (p.G534E and p.R122 W) were found in 2 and 3 patients at the heterozygous level (minor allele frequency (MAF): 5.55% and 8.33%, respectively). The R122 residue lies in the EGF-3 domain of HABP2 which is important for its activation. In controls, the MAF was either lower for the p.R122 W (1.05%, P Discussion In conclusion, our data do not support the pathogenicity of the HABP2 p.G534E variant but highlight the existence of another variant that should be more extensively searched for in fPTC patients.

Family Screening in Familial Papillary Carcinoma: The Early Detection of Thyroid Disease.

Blood relatives of patients with familial papillary thyroid carcinoma (FPTC) have a higher rate of thyroid disease. This study analyzed the utility of a screening protocol for thyroid disease on blood relatives of patients with FPTC. Members of families diagnosed with FPTC. (1) first- and second-degree relatives; and (2) older than age 11years. Screening: This includes the subject's clinical history, a physical examination, blood tests, and an ultrasound examination. A nonrelated healthy population paired by age and sex with the study group. Sixty-eight percent of blood relatives (128/189) accepted having the screening. The results showed 44.5% (n=57) of the relatives did not have disease, 44% (n=56) had benign thyroid disease, and 11.5% (n=15) had a disease suggestive of malignancy. After the screening, surgery was indicated in 26 patients, and the final results of the study were: (1) 44.5% (n=57) were healthy subjects; (2) 50% (n=64) had benign thyroid disease (26 cases with a functional disease, and/or 56 with an organic disease); and (3) 5.5% (n=7) had malignant thyroid disease. The first-degree relatives had a higher tendency to have the disease than second degree ones (64 vs. 46%; p=0.0482). In the control group, the incidence of thyroid cancer was 1.3% compared with 5.5% in the study group (p=0.0182). Screening allows for the early detection of papillary carcinoma and benign thyroid disease and for this reason we recommend that it is performed periodically. However, more studies, with larger sample sizes, are needed to determine the benefit of screening.

HABP2 G534E Variant in Papillary Thyroid Carcinoma.

The main nonmedullary form of thyroid cancer is papillary thyroid carcinoma (PTC) that accounts for 80–90% of all thyroid malignancies. Only 3–10% of PTC patients have a positive family history of PTC yet the familiality is one of the highest of all cancers as measured by case control studies. A handful of genes have been implicated accounting for a small fraction of this genetic predisposition. It was therefore of considerable interest that a mutation in the HABP2 gene was recently implicated in familial PTC. The present work was undertaken to examine the extent of HABP2 variant involvement in PTC. The HABP2 G534E variant (rs7080536) was genotyped in blood DNA from 179 PTC families (one affected individual per family), 1160 sporadic PTC cases and 1395 controls. RNA expression of HABP2 was tested by qPCR in RNA extracted from tumor and normal thyroid tissue from individuals that are homozygous wild-type or heterozygous for the variant. The variant was found to be present in 6.1% familial cases, 8.0% sporadic cases (2 individuals were homozygous for the variant) and 8.7% controls. The variant did not segregate with PTC in one large and 6 smaller families in which it occurred. In keeping with data from the literature and databases the expression of HABP2 was highest in the liver, much lower in 3 other tested tissues (breast, kidney, brain) but not found in thyroid. Given these results showing lack of any involvement we suggest that the putative role of variant HABP2 in PTC should be carefully scrutinized.

Chronic lymphocytic thyroiditis is associated with invasive characteristics of differentiated thyroid carcinoma in children and adolescents.

The association between chronic lymphocytic thyroiditis (CLT) and thyroid cancer is an interesting topic. The aim of the present study was to evaluate if demographic and histological characteristics as well as the long-term outcome of thyroid cancer was different in children and adolescents with and without CLT. The medical records of children and adolescents (≤21 years old) were reviewed. The following data were recorded: gender, year and age at diagnosis, family history of thyroid cancer, history of external radiation therapy, histological type (papillary and variants, follicular and variants), tumour size, multifocality, infiltration of thyroid parenchyma or surrounding soft tissues, vascular invasion, presence of lymph node and distant metastases. Information about the presence of TgAb and TPOAb was also collected. One hundred eight children and adolescents (median age 19.0, interquartile range 4.0 years) were diagnosed with differentiated thyroid carcinoma (DTC); 31 patients (28.7%) presented histological characteristics compatible with CLT. Infiltration of thyroid parenchyma was more frequent in patients with CLT compared to patients without (74.2% vs 48.1% respectively, P=0.024). Familial papillary thyroid carcinoma (PTC) was more frequent in patients with CLT compared to those without CLT (20.7% vs 2.8% respectively, P=0.009). There was no better outcome with respect to the presence of CLT or not. Children and adolescents with CLT present more frequently familial PTC as well as thyroid cancer with invasive characteristics.

Clinicopathological features and prognosis of familial papillary thyroid carcinoma--a large-scale, matched, case-control study.

It remains controversial whether or not the aggressiveness of familial nonmedullary thyroid cancer (FNMTC) differs from sporadic carcinoma. The aim of this study was to determine the clinicopathological features and prognosis of FNMTC. A matched-case comparative study. Three hundred and seventy-two patients with familial papillary thyroid carcinoma (FPTC) were enrolled as the study group, and another 372 patients with sporadic PTC were enrolled as controls and matched for gender, age, tumour/node/metastasis (TNM) staging and approximate duration of follow-up. We compared the differences in the clinicopathological features and prognosis between the subgroups. Compared with sporadic PTC, patients with FPTC were more likely to present tumour multicentricity, bilateral growth and a concomitant nodular goitre (P < 0·05). In papillary thyroid microcarcinoma (PTMC), a higher recurrence rate was noted in patients with a family history of PTC, and this remained independently predictive on multivariate analysis. The patients with FPTC in the second generation showed an earlier age of onset, more frequent Hashimoto's thyroiditis and a higher recurrence rate than the first generation, while the first-generation offspring of patients had a higher incidence of nodular goitre than the second generation. The presence of familial history in PTC indicates an increase in biological aggressiveness, and patients in the second generation may exhibit the 'genetic anticipation' phenomenon. At present, the available data are not sufficient to support a more aggressive approach for FPTC. However, a family history of PTC is an independent risk factor for recurrence in patients with PTMC.