Familial papillary thyroid carcinoma: a retrospective analysis

Distant Metastasis as the First Presentation of Thyroid Carcinoma

Introduction

Thyroid carcinoma is the most common endocrine cancer which may manifest with unusual presentations. We addressed distant metastases as the first presentations of thyroid carcinoma in several patients, though previously considered to occur rarely.

Methods

In this case series, 10 patients are introduced with signs and symptoms of distant metastasis. Detailed history, physical examination, laboratory data, and histopathologic final report of thyroid cancer are presented.

Conclusion

Although it seems unusual to discover a distant metastasis without abnormal thyroid examination, several reports of similar findings urge the need to improve screening process. It is prudent to bear in mind these presentations for early detection of thyroid carcinoma.

Clinical characteristics and prognosis of familial nonmedullary thyroid carcinoma

INTRODUCTION

Familial non-medullary thyroid carcinoma (FNMTC) is defined by the presence of 2 or more first-degree family members with differentiated thyroid carcinoma (DTC). The aim of this study is to compare clinicopathological features and prognosis of FNMTC and sporadic carcinoma (SC).

MATERIALS AND METHODS

Retrospective study of DTC included in the hospital database during the period 1990-2018.

RESULTS

A total of 927 patients were analyzed, 61 of them were FNMTC, with a mean follow-up of 9.7 ± 6.5 years. The prevalence of FNMTC was 6.6%, with a lower TNM staging presentation (P = 0.003) consequence of a higher proportion of tumors smaller than 2 cm (P = 0.003), combined with a greater multifocality (P = 0.034) and papillary histologic subtype (P = 0.022) compared to SC. No significant differences in age at diagnosis (P = 0.347), gender (P = 0.406), neither in other aggressiveness markers (bilaterality, extrathyroidal extension, lymph node involvement and metástasis) were detected. Rate of persistence/recurrence (P = 0.656), disease-free survival (P = 0.929) and mortality caused by the tumor itself (P = 0.666) were comparable. Families with ≥3 affected relatives, had smaller tumors (P = 0.005), more multifocality (P = 0.040) and bilaterality (P = 0.002), as well as a higher proportion of males (P = 0.020). Second generation patients present earlier FNMTC compared to those of the first generation (P = 0.001).

CONCLUSION

In our study FNMTC presents a lower TNM staging, higher multifocality and papillary variant, with similar aggressiveness and prognosis compared to SC.

Preoperative Ultrasonography in the Evaluation of Suspected Familial Non-Medullary Thyroid Cancer: Are We Able to Predict Multifocality and Extrathyroidal Extension?

Family history of thyroid cancer increases the risk of harboring thyroid malignancies that end up having extrathyroidal extension (ETE) and multifocality on histology; some authors suggest a more aggressive surgical approach. Their pre-operative identification could allow more conservative surgical procedures if none of these features are suspected. Our aim was to assess if neck ultrasonography could identify or exclude multifocality or ETE in these patients to tailor the extent of surgery. This retrospective study included patients with previous thyroid surgery, ≥1 first-grade relative with thyroid cancer, and who had undergone pre-surgical ultrasound. ETE was suspected in the case of thyroid border interruption or gross invasion of perithyroidal tissues. Multiple suspicious nodules were defined as suspicion of multifocal cancer. The cohort consisted of 45 patients (median age 49 years, 40 with thyroid cancer, 30 females). The positive predictive value of ultrasonography in predicting multifocality and ETE was 57.14% (25.25–84.03) and 41.67% (21.5–65.1%), respectively, while the negative predictive values were 63.2% (56.4–69.4%) and 72.7% (63.3–80.5%). Pre-operative ultrasound examination is unable to reliably identify or exclude multifocal disease or extrathyroidal extension. In patients scheduled for surgery and with a first-degree relative affected by DTC, a “negative” pre-operative US report does not exclude the potential finding of multifocality and ETE at final histopathology.

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.

Clinical characteristics and prognosis of familial nonmedullary thyroid carcinoma

INTRODUCTION

Familial non-medullary thyroid carcinoma (FNMTC) is defined by the presence of 2or more first-degree family members with differentiated thyroid carcinoma (DTC). The aim of this study is to compare clinicopathological features and prognosis of FNMTC and sporadic carcinoma (SC).

MATERIALS AND METHODS

Retrospective study of DTC included in the hospital database during the period 1990-2018.

RESULTS

A total of 927 patients were analyzed, 61 of them were FNMTC, with a mean follow-up of 9.7±6.5 years. The prevalence of FNMTC was 6.6%, with a lower TNM staging presentation (P=.003) consequence of a higher proportion of tumors smaller than 2 centimeters (P=.003), combined with a greater multifocality (P=.034) and papillary histologic subtype (P=.022) compared to SC. No significant differences in age at diagnosis (P=.347), gender (P=.406), neither in other aggressiveness markers (bilaterality, extrathyroidal extension, lymph node involvement and metástasis) were detected. Rate of persistence/recurrence (P=.656), disease-free survival (P=.929) and mortality caused by the tumor itself (P=.666) were comparable. Families with ≥3 affected relatives, had smaller tumors (P=.005), more multifocality (P=.040) and bilaterality (P=.002), as well as a higher proportion of males (P=.020). Second generation patients present earlier FNMTC compared to those of the first generation (P=.001).

CONCLUSION

In our study FNMTC presents a lower TNM staging, higher multifocality and papillary variant, with similar aggressiveness and prognosis compared to SC.

Co-Occurrence of Familial Non-Medullary Thyroid Cancer (FNMTC) and Hereditary Non-Polyposis Colorectal Cancer (HNPCC) Associated Tumors-A Cohort Study

Familial non-medullary thyroid cancer (FNMTC) is a form of endocrine malignancy exhibiting an autosomal dominant mode of inheritance with largely unknown germline molecular mechanism. Hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is another hereditary autosomal dominant cancer syndrome which, if proven to be caused by germline mutations in mismatch repair genes (MMR)-MLHL, MSH2, MSH6, PMS2, and EPCAM-is called Lynch syndrome (LS). LS results in hereditary predisposition to a number of cancers, especially colorectal and endometrial cancers. Tumors in LS are characterized by microsatellite instability (MSI) and/or loss of MMR protein expression in immunohistochemistry (IHC). MSI is a rare event in thyroid cancer (TC), although it is known to occur in up to 2.5% of sporadic follicular TC cases. There are limited data on the role of germline MMR variants FNMTC. The goal of this study was to analyze the potential clinical and molecular association between HNPCC and FNMTC. We performed a cohort study analyzing the demographic, clinical, and pathologic data of 43 kindreds encompassing 383 participants (104 affected, 279 unaffected), aged 43.5 [7-99] years with FNMTC, and performed high-throughput whole-exome sequencing (WES) of peripheral blood DNA samples of selected 168 participants (54 affected by FNMTC and 114 unaffected). Total affected by thyroid cancer members per family ranged between 2 and 9 patients. FNMTC was more prevalent in women (68.3%) and characterized by a median tumor size of 1.0 [0.2-5.0] cm, multifocal growth in 44%, and gross extrathyroidal extension in 11.3%. Central neck lymph node metastases were found in 40.3% of patients at presentation, 12.9% presented with lateral neck lymph node metastases, and none had distant metastases. Family history screening revealed one Caucasian family meeting the clinical criteria for FNMTC and HNPCC, with five members affected by FNMTC and at least eight individuals reportedly unaffected by HNPCC-associated tumors. In addition, two family members were affected by melanoma. Genome Analysis Tool Kit (GATK) pipeline was used in variant analysis. Among 168 sequenced participants, a heterozygous missense variant in the MSH2 gene (rs373226409; c.2120G>A; p.Cys707Tyr) was detected exclusively in FNMTC- HNPCC- kindred. In this family, the sequencing was performed in one member affected by FNMTC, HPNCC-associated tumors and melanoma, one member affected solely by HNPCC-associated tumor, and one member with FNMTC only, as well as seven unaffected family members. The variant was present in all three affected adults, and in two unaffected children of the affected member, under the age of 18 years, and was absent in non-affected adults. This variant is predicted to be damaging/pathogenic in 17/20 in-silico models. However, immunostaining performed on the thyroid tumor tissue of two affected by FNMTC family members revealed intact nuclear expression of MSH2, and microsatellite stable status in both tumors that were tested. Although the MSH2 p.Cys707Tyr variant is rare with a minor allele frequency (MAF) of 0.00006 in Caucasians; it is more common in the South Asian population at 0.003 MAF. Therefore, the MSH2 variant observed in this family is unlikely to be an etiologic factor of thyroid cancer and a common genetic association between FNMTC and HNPCC has not yet been identified. This is the first report known to us on the co-occurrence of FNMTC and HNPCC. The co-occurrence of FNMTC and HNPCC-associated tumors is a rare event and although presented in a single family in our large FNMTC cohort, a common genetic background between the two comorbidities could not be established.

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.

Longer Time to Reach Excellent Response to Treatment in Familial Versus Sporadic Non-medullary Thyroid Cancer (NMTC): A Matched Case-Control Study

BACKGROUND

Familial non-medullary thyroid cancer (NMTC) are supposed to be more aggressive and require more frequent treatment compared to non-familial thyroid cancer.

OBJECTIVES

This matched case-control study aimed to compare the response to treatment between the matched case-control groups of familial and sporadic NMTC.

METHODS

This is a retrospective study in patients with familial NMTC (at least one other first-degree relative involved) who were treated with surgery, followed by radio-iodine therapy (RIT) without consideration of its familial origin. Response to treatment was compared between familial NMTC and age, sex, and TNM stage-matched non-familial NMTC (control group). Response to treatment was assessed one and two years after RIT, and time to excellent response was identified.

RESULTS

Out of 2,944 NMTC patients, 81 (2.75%) patients had familial NMTC. We compared 66 patients with familial NMTC and 66 sporadic NMTC patients. There was no significant difference in first thyroglobulin, initial and accumulative iodine dose, and additional treatments (additional surgery and radiotherapy) between patients and controls. Although no significant difference was noted in one and two years' responses to treatment between the case and control groups, familial NMTC patients required more time to achieve excellent response (26.7 ± 24.9 versus 15.9 ± 9.0 months, P = 0.01). No significant difference was noted between familial NMTC patients with two or more than two involved relatives.

CONCLUSIONS

Our study showed that if patients with familial NMTCs were treated in the same way as non-familial patients, the time to excellent response would be significantly longer, even when they have only one other involved relative.

Inherited Follicular Epithelial-Derived Thyroid Carcinomas: From Molecular Biology to Histological Correlates

Cancer derived from thyroid follicular epithelial cells is common; it represents the most common endocrine malignancy. The molecular features of sporadic tumors have been clarified in the past decade. However the incidence of familial disease has not been emphasized and is often overlooked in routine practice. A careful clinical documentation of family history or familial syndromes that can be associated with thyroid disease can help identify germline susceptibility-driven thyroid neoplasia. In this review, we summarize a large body of information about both syndromic and non-syndromic familial thyroid carcinomas. A significant number of patients with inherited non-medullary thyroid carcinomas manifest disease that appears to be sporadic disease even in some syndromic cases. The cytomorphology of the tumor(s), molecular immunohistochemistry, the findings in the non-tumorous thyroid parenchyma and other associated lesions may provide insight into the underlying syndromic disorder. However, the increasing evidence of familial predisposition to non-syndromic thyroid cancers is raising questions about the importance of genetics and epigenetics. What appears to be "sporadic" is becoming less often truly so and more often an opportunity to identify and understand novel genetic variants that underlie tumorigenesis. Pathologists must be aware of the unusual morphologic features that should prompt germline screening. Therefore, recognition of harbingers of specific germline susceptibility syndromes can assist in providing information to facilitate early detection to prevent aggressive disease.

Should Total Thyroidectomy Be Recommended for Patients with Familial Non-medullary Thyroid Cancer?

BACKGROUND

It is unknown whether familial non-medullary thyroid cancer (FNMTC) has more aggressive clinical features and a worse prognosis than sporadic non-medullary thyroid cancer (SNMTC).

METHODS

We retrospectively reviewed 2894 patients with differentiated thyroid cancer who underwent primary thyroidectomy, identified 391 FNMTC cases, and compared the prevalence, surgical extension, and clinicopathologic features of FNMTC and SNMTC.

RESULTS

A family history of thyroid cancer was noted in 391 patients (13.5%), with 85% having two affected relatives and 15% with ≥3 affected relatives. A sibling was affected in 52.9% of cases, and in 47.1%, both parent and child were affected. There were no significant between-group differences in sex, age, tumor size, extrathyroidal extension, or central lymph node metastases. Significantly more patients with FNMTC exhibited multifocal disease (p = 0.020) or benign nodules (p = 0.015). Lateral neck lymph node metastases were noted in 6.6% (SNMTC) and 9.7% (FNMTC, p = 0.021) of patients. Multifocality and combined benign masses were more frequently observed in patients with FNMTC in multivariate analysis. In the FNMTC group, seven experienced disease recurrence, with no mortality noted during follow-up.

CONCLUSIONS

FNMTC is not more aggressive than SNMTC; however, FNMTC should be treated with total thyroidectomy because of the increased disease multifocality and the presence of benign nodules. Lateral neck lymph node metastases were more likely in patients with FNMTC, although we could not estimate prognosis. All patients with thyroid cancer should be checked for family disease history and undergo preoperative ultrasonography to determine the extent of node dissection and the need for total thyroidectomy.

Is Familial Nonmedullary Thyroid Cancer A More Aggressive Type of Thyroid Cancer?

OBJECTIVES

Familial non-medullary thyroid cancer (FNMTC) is a distinct entity, increasingly diagnosed. By lacking an accurate genetic diagnostic test, its diagnosis is currently clinically based, with an ongoing debate over whether it has a more aggressive clinical behavior than sporadic non-medullary thyroid cancer (SNMTC). We seek to compare in this study, the clinicopathological variables, and the outcome of FNMTC versus SNMTC patients.

METHODS

We retrospectively searched a database of 465 patients that underwent thyroidectomy at Assaf Harofeh Medical Center (91.4% between 1990 and 2019) for demographics, risk factors, medical history, diagnostic workup, primary treatment, follow-up, and disease outcome data. We compared 47 FNMTC versus 321 SNMTC patients, and FNMTC patients with ≥2 (n = 34) versus ≥3 (n = 13) first-relative affected members.

RESULTS

There were no significant differences in demographics, histopathology, TNM stage, treatment, and disease outcome between the FNMTC and SNMTC groups. The T2 and T4 tumor stage in the ≥3-member group were 25% and 8.3% compared to 0% and 0% in the two-member group (P = .02 and P = ns, respectively). Also, LN involvement was significantly higher in the ≥3-member group (61.6% vs. 24.2%, respectively; P = .036).

CONCLUSION

FNMTC is not a more aggressive disease than SNMTC, but this may not apply for the ≥3-affected-relatives group. A large multicenter study including only families with three or more affected relatives is needed. Until then, a family history of NMTC should not be overlooked.

LEVEL OF EVIDENCE

3/5 Laryngoscope, 131:E677-E681, 2021.

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.

Risk Factors for Thyroid Cancer: What Do We Know So Far?

Thyroid cancer (TC) is the most common endocrine cancer today. The rising incidence of the differentiated papillary type cannot be entirely explained by early and meticulous diagnosis, since a proportion of large tumors has also been reported. In this review, we present the results of numerous investigations focused on possible factors causing increased TC incidence, such as chromosomal and genetic alterations, iodine intake, TSH level, autoimmune thyroid disease, gender, estrogen, obesity, lifestyle changes, and environmental pollutants. Up to now, only childhood exposure to ionizing radiation has been fully recognized as a risk factor. There is also a possibility that yet undiscovered carcinogens, especially during intrauterine life or early childhood, might be responsible for increased TC incidence as well as epigenetic changes. Therefore, more studies are necessary in order to further investigate the potential risk factors for TC and their mechanisms of action.

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.

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 methods

A 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.

Identification of Rare Variants Predisposing to Thyroid Cancer

Background: Familial non-medullary thyroid cancer (NMTC) accounts for a relatively small proportion of thyroid cancer cases, but it displays strong genetic predisposition. So far, only a few NMTC susceptible genes and low-penetrance variants contributing to NMTC have been described. This study aimed to identify rare germline variants that may predispose individuals to NMTC by sequencing a cohort of 17 NMTC families. Methods: Whole-genome sequencing and genome-wide linkage analysis were performed in 17 NMTC families. MendelScan and BasePlayer were applied to screen germline variants followed by customized filtering. The remaining candidate variants were subsequently validated by Sanger sequencing. A panel of 277 known cancer predisposition genes was also screened in these families. Results: A total of 41 rare coding candidate variants in 40 genes identified by whole-genome sequencing are reported, including 24 missense, five frameshift, five splice change, and seven nonsense variants. Sanger sequencing confirmed all 41 rare variants and proved their co-segregation with NMTC in the extended pedigrees. In silico functional analysis of the candidate genes using Ingenuity Pathway Analysis showed that cancer was the top category of "Diseases and Disorders." Additionally, a targeted search displayed six variants in known cancer predisposition genes, including one frameshift variant and five missense variants. Conclusions: The data identify rare germline variants that may play important roles in NMTC predisposition. It is proposed that in future research including functional characterization, these variants and genes be considered primary candidates for thyroid cancer predisposition.

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.

Familial Nonmedullary Thyroid Carcinoma: A Retrospective Analysis of 117 Families

Background:

The first and most important step in characterizing familial nonmedullary thyroid carcinoma (NMTC) is to distinguish the true familial patients, which is the prerequisite for all accurate analyses. This study aimed to investigate whether patients from families with ≥3 first-degree relatives affected with NMTC have different characteristics than patients from families with only two affected members, and to compare these patients with those with sporadic disease.

Methods:

We analyzed the clinicopathological features and prognosis of 209 familial and 1120 sporadic cases of NMTC. Familial patients were further divided into two subgroups: families with two affected members and families with ≥3 affected members.

Results:

The familial group had a significantly higher risk of bilateral growth, multifocality, extrathyroidal extension, and lateral lymph node metastasis than the sporadic group (P < 0.05). These main features were also different between the group with ≥3 affected members and the sporadic group. The only difference between the two affected members' group and the sporadic group was incidence of multifocality (P < 0.05). The probability of disease recurrence in patients from families with ≥3 affected members was significantly higher than that in sporadic cases (14.46% vs. 5.27%; P = 0.001), while the probability in patients from families with two affected members was similar to that in sporadic patients (6.35% vs. 5.27%; P = 0.610). The Kaplan–Meier survival analysis showed a statistically significant difference in disease-free survival between the two subgroups (85.54% vs. 93.65%; P = 0.045).

Conclusions:

Patients from families with ≥3 members affected by NMTC have more aggressive features and a worse prognosis than those from families with only two affected members. Patients from families with ≥3 affected first-degree relatives may be considered to have true familial NMTC.

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.

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 10 years, 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.

Clinical Analysis of Familial Nonmedullary Thyroid Carcinoma

OBJECTIVE

To analyze the clinical characteristics of familial nonmedullary thyroid carcinoma (FNMTC), in order to provide evidence for early diagnosis and treatment.

METHODS

We retrospectively investigated the inpatients between September 2006 and September 2013 in the First Bethune Hospital of Jilin University, in which 78 patients with FNMTC from 31 families were analyzed by a comparison with 3445 control cases from the patients with sporadic nonmedullary thyroid carcinoma (SNMTC).

RESULTS

There was no significant difference in gender, age, and tumor size between FNMTC and SNMTC patients. However, the characteristics of disease in multifoci, neck lymph node metastasis, invasion to the surrounding tissues, and coexistence with Hashimoto disease in two types of cancer patients show significant difference. They are: multifoci: 71.8% (56/78) in FNMTC versus 46.3% (1595/3445) in SNMTC; neck lymph node metastasis: 52.6% (41/78) in FNMTC versus 33.3% (1148/3445) in SNMTC; surrounding tissue invasion: 64.1% (50/78) in FNMTC versus 48.5% (1670/3445) in SNMTC; coexistence with Hashimoto disease: 30.8% (24/78) in FNMTC versus 20.0% (689/3445) in SNMTC.

CONCLUSION

Lymph node metastasis, multifoci, invasion to the surrounding tissues, and combination with chronic lymphocytic thyroiditis are the main features of FNMTC, which suggests the extent of the operation for FNMTC patients should be amplified properly.

HABP2 germline variants are uncommon in familial nonmedullary thyroid cancer

Background

The genetic basis of nonsyndromic familial nonmedullary thyroid cancer (FNMTC) is poorly understood. A recent study identified HABP2 as a tumor suppressor gene and identified a germline variant (G534E) in an extended FNMTC kindred. The relevance of this to other FNMTC kindreds is uncertain.

Methods

Sanger sequencing was performed on peripheral blood DNA from probands from 37 Australian FNMTC kindreds to detect the G534E variant. Whole exome data from 59 participants from 20 kindreds were examined for mutations in HABP2 and the thyroid cancer susceptibility genes SRGAP1, NKX2-1, SRRM2 and FOXE1. The population prevalence of the G534E variant in HABP2 was examined in two independent cohorts.

Results

Heterozygosity for the G534E variant in HABP2 was found in 1 of 37 probands (2.7 %), but did not cosegregate with disease in this kindred, being absent in the proband’s affected sister. From whole exome data, pathogenic mutations were not identified in HABP2, SRGAP1, NKX2-1, SRRM2 or FOXE1. Heterozygosity for the G534E variant in HABP2 was present in 7.6 % of Busselton Health Study participants (N = 4634, unknown disease status) and 9.3 % of TwinsUK participants (N = 1195, no history of thyroid cancer).

Conclusions

The G534E variant in HABP2 does not account for the familial nature of NMTC in Australian kindreds, and is common in the general population. Further research is required to elucidate the genetic basis of nonsyndromic FNMTC.

The impact of family history on non-medullary thyroid cancer

INTRODUCTION

Around 10% of patients with non-medullary thyroid cancer (NMTC) will have a positive family history for the disease. Although many will be sporadic, families where 3 first-degree relatives are affected can be considered to represent true familial non-medullary thyroid cancer (FNMTC). The genetic basis, impact on clinical and pathological features, and overall effect on prognosis are poorly understood.

METHODS

A literature review identified articles which report on genetic, clinical, therapeutic and screening aspects of FNMTC. The results are presented to allow an understanding of the genetic basis and the impact on clinical-pathological features and prognosis in order to inform clinical decision making.

RESULTS

The genetic basis of FNMTC is unknown. Despite this, significant progress has been made in identifying potential susceptibility genes. The lack of a test for FNMTC has led to a clinical definition requiring a minimum of 3 first-degree relatives to be diagnosed with NMTC. Although some have shown an association with multi-centric disease, younger age and increased rates of extra-thyroidal extension and nodal metastases, these findings are not supported by all. The impact of FNMTC is unclear with all groups reporting good outcome, and some finding an association with more aggressive disease. The role of screening remains controversial.

CONCLUSION

FNMTC is rare but can be diagnosed clinically. Its impact on prognostic factors and the subsequent role in influencing management is debated. For those patients who present with otherwise low-risk differentiated thyroid cancer, FNMTC should be included in risk assessment when discussing therapeutic options.

Three siblings with familial non-medullary thyroid carcinoma: a case series

Background

In 2015, thyroid carcinoma affected approximately 63,000 people in the USA, yet it remains one of the most treatable cancers. It is mainly classified into medullary and non-medullary types. Conventionally, medullary carcinoma was associated with heritability but increasing reports have now begun to associate non-medullary thyroid carcinoma with a genetic predisposition as well. It is important to identify a possible familial association in patients diagnosed with non-medullary thyroid carcinoma because these cancers behave more destructively than would otherwise be expected. Therefore, it is important to aggressively manage such patients and screening of close relatives might be justified. Our case series presents a diagnosis of familial, non-syndromic, non-medullary carcinoma of the thyroid gland in three brothers diagnosed over a span of 6 years.

Case presentations

We report the history, signs and symptoms, laboratory results, imaging, and histopathology of the thyroid gland of three Pakistani brothers of 58 years, 55 years, and 52 years from Sindh with non-medullary thyroid carcinoma. Only Patients 1 and 3 had active complaints of swelling and pruritus, respectively, whereas Patient 2 was asymptomatic. Patients 2 and 3 had advanced disease at presentation with lymph node metastasis. All patients underwent a total thyroidectomy with Patients 2 and 3 requiring a neck dissection as well. No previous exposure to radiation was present in any of the patients. Their mother had died from adrenal carcinoma but also had a swelling in the front of her neck which was never investigated. All patients remained stable at follow-up.

Conclusions

Non-medullary thyroid carcinoma is classically considered a sporadic condition. Our case report emphasizes a high index of suspicion, a detailed family history, and screening of first degree relatives when evaluating patients with non-medullary thyroid carcinoma to rule out familial cases which might behave more aggressively.

Risk of Thyroid Cancer in Euthyroid Asymptomatic Patients with Thyroid Nodules with an Emphasis on Family History of Thyroid Cancer

Objective

To determine the factors associated with thyroid cancer, focusing on first-degree family history and ultrasonography (US) features, in euthyroid asymptomatic patients with thyroid nodules.

Materials and Methods

This retrospective study included 1310 thyroid nodules of 1254 euthyroid asymptomatic patients who underwent US-guided fine-needle aspiration biopsy between November 2012 and August 2013. Nodule size and clinical risk factors–such as patient age, gender, first-degree family history of thyroid cancer, multiplicity on US and serum thyroid stimulating hormone (TSH) levels–were considered together with US features to compare benign and malignant nodules. Multiple logistic regression analysis was performed to assess the risk of thyroid malignancy according to clinical and US characteristics.

Results

Although all of the clinical factors and US findings were significantly different between patients with benign and malignant nodules, a solitary lesion on US (p = 0.041–0.043), US features and male gender (p < 0.001) were significant independent risk factors for thyroid malignancy in a multivariate analysis. Patient age, a first-degree family history of thyroid cancer and high normal serum TSH levels did not independently significantly increase the risk of thyroid cancer. However, multicollinearity existed between US assessment and patient age, first-degree family history of thyroid cancer and serum TSH values.

Conclusion

Ultrasonography findings should be the primary criterion used to decide the management of euthyroid asymptomatic patients with thyroid nodules. The concept of first-degree family history as a risk factor for thyroid malignancy should be further studied in asymptomatic patients.

Treatment Outcomes and Risk Factors for Recurrence After Definitive Surgery of Locally Invasive Well-Differentiated Papillary Thyroid Carcinoma

BACKGROUND

Papillary thyroid carcinoma (PTC) is generally an indolent tumor that has a favorable prognosis. However, locally invasive PTC can recur after treatment, and its optimal treatment is still controversial. This study aimed to evaluate treatment outcomes and identify risk factors for recurrence and survival in patients with locally invasive PTC.

MATERIALS AND METHODS

All consecutive patients who underwent definitive surgery and radioactive iodine therapy for non-distant metastatic invasive PTC were included. Clinical factors, operative and pathological findings, surgical morbidity, and recurrences were recorded. Univariate and multivariate Cox proportional hazard models served to identify factors associated with recurrence-free survival (RFS) and overall survival.

RESULTS

Of the 96 patients, 74 (77%), 52 (55%), 4 (4%), and 14 (15%) had invasion to the recurrent laryngeal nerve (RLN), trachea, larynx, and esophagus, respectively; 39 (41%) had preoperative vocal cord paresis or paralysis; and 24 (25%) developed recurrence during follow-up (median 77 months). The patients with single and multiple organ invasion did not differ significantly in terms of recurrence-free or overall survival (p > 0.05). The patients with and without recurrences did not differ in terms of surgical extent and involving nerve preservation. Multivariate analysis showed that high (≥1 ng/mL) post-ablation stimulated serum thyroglobulin concentration was an independent predictor of poor RFS (p = 0.013).

CONCLUSION

Disease extent, surgical extent, and involving nerve preservation did not associate with recurrence or overall survival outcomes. The post-ablation stimulated thyroglobulin level may be an independent predictor for recurrence. Careful follow-up of patients with this risk factor is recommended.

Comparison of Clinical and Ultrasonographic Features of Poorly Differentiated Thyroid Carcinoma and Papillary Thyroid Carcinoma

Background:

The clinical behavior and management of poorly differentiated thyroid carcinoma (PDTC) are very different from papillary thyroid carcinoma (PTC). By comparing the clinical and ultrasonographic features between the two tumors, we proposed to provide more possibilities for recognizing PDTC before treatment.

Methods:

The data of 13 PDTCs and 39 age- and gender-matched PTCs in Peking Union Medical College Hospital between December 2003 and September 2013 were retrospectively reviewed. The clinical and ultrasonic features between the two groups were compared.

Results:

The frequencies of family history of carcinoma, complication with other thyroid lesions, lymph node metastases, recurrent laryngeal nerve injuries, and distant metastases were higher in PDTCs (30.8%, 61.6%, 69.2%, 23.1%, and 46.2%, respectively) than those in PTCs (2.6%, 23.1%, 25.6%, 2.6%, and 2.6%, respectively) (P < 0.05). The mortality rate of PDTCs was greatly higher than PTCs (P < 0.01). Conventional ultrasound showed that the size of PDTCs was larger than that of PTCs (3.1 ± 1.9 cm vs. 1.7 ± 1.0 cm). Clear margins and rich and/or irregular blood flow were found in 92.3% of PDTCs, which differed substantially from PTCs (51.7% and 53.8%, respectively) (P < 0.05).

Conclusions:

PDTC is more aggressive and its mortality rate is higher than PTCs. Accordingly, more attention should be given to suspicious thyroid cancer nodules that show large size, regular shape, and rich blood flow signals on ultrasound to exclude the possibility of PDTCs.

RAS/BRAF mutational status in familial non-medullary thyroid carcinomas: A retrospective study

There are contrasting views on whether familial non-medullary thyroid carcinomas (FNMTCs) are characterized by aggressive behavior, and limited evidence exists on the prognostic value of BRAF and RAS mutations in these tumors. Thus, in the present study, clinicopathological features were analyzed in 386 non-medullary thyroid carcinomas (NMTCs), subdivided in 82 familial and 304 sporadic cases. Furthermore, the RAS and BRAF mutational statuses were investigated in a subgroup of 34 FNMTCs to address their clinical and biological significance. The results demonstrated that, compared with sporadic NMTCs, FNMTCs are characterized by significantly higher rates of multicentricity and bilaterality and are more frequently associated with chronic autoimmune thyroiditis. Notably, a statistically significant difference in the rates of multicentricity was observed by subgrouping familial tumors according to the number of relatives involved; those with ≥3 affected relatives were more likely to be multicentric. Furthermore, the FNMTC cohort exhibited higher rates of tumors >4 cm in size with extrathyroidal or lymph node involvement. However, no significant difference was observed. Similarly, no differences were observed with respect to the age of onset or the patient outcome. The mutational profiling exhibited a rate of 58.8% for BRAF V600E mutations in familial tumors, which is at the upper limit of the mutational frequency observed in historical series of sporadic thyroid cancer. A high rate of NRAS mutations (17.6%) was also observed, mostly in the follicular variant histotype. Notably, compared with BRAF/RAS-wild type FNMTCs, the familial carcinomas bearing BRAF or NRAS mutations exhibited slightly higher rates of bilaterality and multicentricity, in addition to increased frequency of locally advanced stage or lymph node involvement. The present data support the theory that FNMTCs are characterized by clinicopathological features that resemble a more aggressive phenotype and suggest that RAS/BRAF mutational analysis deserves to be further evaluated as a tool for the identification of FNMTCs with a potentially unfavorable prognosis.

Clinicopathologic features of familial nonmedullary thyroid carcinoma

BACKGROUND

Familial nonmedullary thyroid carcinoma (FNMTC) is a variant of nonmedullary thyroid carcinoma(NMTC) with particular clinicopathologic features. In recent years, a number of studies have shown that FNMTC is more invasive than sporadic NMTC(SNMTC). The purpose of this study was to explore the differences in clinicopathologic features of FNMTC between different types of families and to determine in which of these families more invasive FNMTC occurred.

METHODS

We retrospectively reviewed all patients with thyroid carcinoma admitted to Peking Union Medical College Hospital from January 2009 to July 2013 in the database. Of all 2000 cases, 55 met the inclusive criteria for FNMTC and were studied. There are two different grouping methods. The first is that all samples were allocated to families with three or more first-degree relatives affected (FNMTC-3 group) and families with only two affected first-degree relatives (FNMTC-2 group). The second is that all patients were divided into families with three or more affected first-degree relatives over two generations (FNMTC-3-2 group) and the other families. We compared the clinicopathologic features such as sex, age, tumor size, multifocality, location, complications by thyroiditis, complications by benign thyroid nodules, surgical procedure, capsule invasion, histological type, lymph node metastases, tumor node metastasis stage, and BRAF mutation between FNMTC-2 group and FNMTC-3 group. We also made the same comparison between FNMTC-3-2 group and other families.

RESULTS

No pronounced differences in clinicopathological features were present between FNMTC-2 group and FNMTC-3 group. The proportion of FNMTC-3-2 group aged <45 years was significantly higher than that in the other families (58.8% vs. 26.3%, P = 0.021). A similar difference was found in the proportion of lymph node metastasis (64.7% vs. 34.2%, P = 0.035).

CONCLUSIONS

FNMTC-3-2 is more invasive than the other families. Early screening and positive treatment for members of these families are recommended.

Single-center study of familial papillary thyroid cancer in China: surgical considerations

Background

Whether familial papillary thyroid cancer (FPTC) is more aggressive than sporadic counterpart remains elusive, and the optimal clinical approach for FPTC is yet to be established. In this study, we investigated familial occurrence of PTC in China and reviewed our experience of its surgical treatment.

Methods

The clinical records of 248 consecutive patients with an established diagnosis of PTC who were admitted to Nanfang Hospital for thyroidectomy between January 2011 and June 2013 were analyzed in this study. Patients included 66 males and 182 females, aged 11 to 76 years.

Results

Twenty-two patients (8.9%) with a positive family history were confirmed. Patients with FPTC had a predilection for female subjects and tended to be younger than other patients, but the difference was not significant (P = 0.0514 and P = 0.168). They were more likely to present large tumors (P = 0.0024), multifocality (familial vs. sporadic: 54.50% vs. 26.50%; P < 0.006), local invasion (81.8% vs. 23.9%; P < 0.001), and malignant lymph nodes (63.6% vs. 33.6%; P = 0.005). Univariate and multivariate analyses identified that a positive family history was an independent risk factor for local invasion (OR: 5.683; 95% CI: 2.056 to 15.707; P = 0.001), malignant lymph nodes (OR: 3.005; 95% CI: 1.046 to 8.630; P = 0.041) in FPTC patients. Kaplan-Meier survival curves revealed that an aggressive surgical strategy was associated with a better relapse-free survival than conventional one (P = 0.032).

Conclusions

FPTC is more likely to possess aggressive features than sporadic counterparts. Thus, screening of at-risk families is essential to aid in earlier recognition. An aggressive surgical strategy appeared to be the more effective therapy. However, sufficient detailed interrogation and long-term follow-up of the patients and their family are necessary for providing individualized recommendations for clinical management.

Familial Non-Medullary Thyroid Cancer Represents an Independent Risk Factor for Increased Cancer Aggressiveness: A Retrospective Analysis of 74 Families

OBJECTIVES

To assess whether familial non-medullary thyroid cancer (FNMTC) represents an independent risk factor for increased aggressiveness of the tumor, as concern as the clinical presentation and the long-term follow-up in respect of sporadic differentiated thyroid cancer (SDTC).

DESIGN

Retrospective study; 1976-2014.

PATIENTS AND METHODS

Seventy-four FNMTC families (151 affected individuals): family relationship and number of affected family members were evaluated. Clinical and histopathological features and outcome were compared to that of 643 SDTC patients followed in the same period according to the same institutional protocols. Median follow-up was 57.7 months (range 12-136) in FNMTC and 59.7 (range 15-94.6) in SDTC patients.

RESULTS

Three cases occurred in 3 families and 2 cases in the other 71. F:M was 3.7:1 in FNMTC and 4.3:1 in SDTC (NS). The family relationship was siblings in 62.2%. Mean age at diagnosis was lower in FNMTC than in SDTC (p < 0.005). Papillary/follicular histotype distribution was similar (86%). Papillary tumors were more frequently multifocal in FNMTC (p = 0.004) and with lymph-node metastases (p = 0.016). Disease-free survival (DFS) was shorter in FNMTC vs. SDTC (p < 0.0001) with 74.8 vs. 90.8% patients free of disease at the last control (p < 0.005). Three patients died in FNMTC group vs. 1 in SDTC (p = 0.02).

CONCLUSION

Familial non-medullary thyroid cancer displays distinct characteristics as earlier age of onset and increased aggressiveness at diagnosis and a higher rate of persistent/recurrent disease and mortality with a shorter DFS in respect with SDTC. FNMTC patients, therefore, should be followed accurately. As the specific gene (or genes) responsible for susceptibility for FNMTC has not yet been identified, a low frequency periodic screening of relatives DTC patients may be useful to identify FNMTC patients at early stage of disease.

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).

Thyroid cancer complicating familial adenomatous polyposis: mutation spectrum of at-risk individuals

Background

Lifetime risk of thyroid cancer associated with FAP has been reported as 1-2%. The mean age at diagnosis of thyroid carcinoma in FAP has been reported at 28 years. The aims of this paper are to better understand gene mutations associated with thyroid cancer and refine surveillance recommendations for patients with FAP.

Methods

We performed a search in Pubmed, Ovid Medline and Embase with the terms ("Thyroid Gland"[Mesh] OR "Thyroid Neoplasms"[Mesh]) AND "Adenomatous Polyposis Coli"[Meshdenomatous Polyposis Coli"[Mesh] to identify subjects with thyroid cancer and FAP. As a reference group for APC mutations in the unselected FAP population, we used the UMD-APC database referenced in the Orphanet portal, which includes APC mutation data on 2040 individuals with FAP.

Results

There were 115 reported cases of thyroid cancer in patients with FAP (95 female: 11 male) with an average age of 29.2 years. Gene mutation testing results were reported in 48 patients. On comparing the prevalence of APC mutation in the population of FAP patients with thyroid cancer and the prevalence of the same mutation in the reference population an increased odds ratio was evident in individuals harboring an APC mutation at codon 1061 (OR: CI 4.1: 1.7-8.9). Analysis of the prevalence of thyroid cancer in individuals with FAP segregated by the region of the gene affected shows an increased risk of thyroid cancer in individuals harboring mutations proximal to codon 512 (OR 2.6, p 0.0099).

Conclusions

There is increased risk for thyroid cancer in individuals with APC mutations at the 5' end (proximal to codon 528) along with the established high risk group harboring mutation at codon 1061. It is suggested that these patients might benefit from directed surveillance by annual ultrasound from age 18 years onwards.

A differential diagnosis of inherited endocrine tumors and their tumor counterparts

Inherited endocrine tumors have been increasingly recognized in clinical practice, although some difficulties still exist in differentiating these conditions from their sporadic endocrine tumor counterparts. Here, we list the 12 main topics that could add helpful information and clues for performing an early differential diagnosis to distinguish between these conditions. The early diagnosis of patients with inherited endocrine tumors may be performed either clinically or by mutation analysis in at-risk individuals. Early detection usually has a large impact in tumor management, allowing preventive clinical or surgical therapy in most cases. Advice for the clinical and surgical management of inherited endocrine tumors is also discussed. In addition, recent clinical and genetic advances for 17 different forms of inherited endocrine tumors are briefly reviewed.