Beata Jurecka-Lubieniecka

Differences in Gene-Gene Interactions in Graves’ Disease Patients Stratified by Age of Onset

Background Graves’ disease (GD) is a complex disease in which genetic predisposition is modified by environmental factors. Each gene exerts limited effects on the development of autoimmune disease (OR = 1.2–1.5). An epidemiological study revealed that nearly 70% of the risk of developing inherited autoimmunological thyroid diseases (AITD) is the result of gene interactions. In the present study, we analyzed the effects of the interactions of multiple loci on the genetic predisposition to GD. The aim of our analyses was to identify pairs of genes that exhibit a multiplicative interaction effect. Material and Methods A total of 709 patients with GD were included in the study. The patients were stratified into more homogeneous groups depending on the age at time of GD onset: younger patients less than 30 years of age and older patients greater than 30 years of age. Association analyses were performed for genes that influence the development of GD: HLADRB1, PTPN22, CTLA4 and TSHR. The interactions among polymorphisms were analyzed using the multiple logistic regression and multifactor dimensionality reduction (MDR) methods. Results GD patients stratified by the age of onset differed in the allele frequencies of the HLADRB1*03 and 1858T polymorphisms of the PTPN22 gene (OR = 1.7, p = 0.003; OR = 1.49, p = 0.01, respectively). We evaluated the genetic interactions of four SNPs in a pairwise fashion with regard to disease risk. The coexistence of HLADRB1 with CTLA4 or HLADRB1 with PTPN22 exhibited interactions on more than additive levels (OR = 3.64, p = 0.002; OR = 4.20, p < 0.001, respectively). These results suggest that interactions between these pairs of genes contribute to the development of GD. MDR analysis confirmed these interactions. Conclusion In contrast to a single gene effect, we observed that interactions between the HLADRB1/PTPN22 and HLADRB1/CTLA4 genes more closely predicted the risk of GD onset in young patients.

Presentation of points of general discussion and voting among the speakers of the European Thyroid Association-Cancer Research Network (ETA-CRN) meeting in Lisbon, 2009, entitled ”European comments to ATA medullary thyroid cancer guidelines”

The main subjects of discussion, held online within the ETA-CRN board invited 16 expert-panelists are shown. The ad hoc emerged ETA-CRN panel of experts (EPE) first congratulated Professor Kloos and the ATA Taskforce for the extensive work on medullary thyroid cancer, and appreciated discussing the ATA guidelines during the ETA-CRN meeting. As it was not possible for all experts to visit the meeting, they enclosed their comments in the online ETA forum. The overall intention was to evaluate certain discrepancies between the ATA guidelines and were biased European clinical practice.All discussants were aware that the ATA guidelines had followed evidence based medicine rules; however, it was intended to reach an European consensus in this matter. The results of online voting among the EPE are shown.We received answers from nine experts. The particular ATA guidelines devoted to the management of MTC ranged in agreement in 0/9 to 4/9. This did not reflect the general, good assessment of the guidelines, as of votes a set of questions.The strongest discrepancies were found in assessment of the usefulness of pentagastrin (Peptavlon®) stimulated calcitonin secretion. The majority of the EPE (5/9) chose an option: “the increase of the basal Ct >100 ng/L means the substantial risk of MTC. However, there should also have been a recommendation for the grey zone 10-100 ng/L, where stimulation with pentagastrin is useful. The cut-off to perform stimulation test at ≤ 15-20 ng/L and values >100 ng/L means a significant suspicion of MTC”.Similarly, attention from the EPE was raised towards the surgical procedures in MTC, particularly the extent and indications for lymph node surgical intervention. Four questions were related to the indications to lymphadenectomy and extent of surgery. The equal number (4/8) of EPE agreed with the ATA R61 and half of the ETA-CRN panel of experts disagreed because the indications to lymphadenectomy (Lx) depended in their opinion on the tumors detected by the Ct screening, in which prophylactic Lx might not be necessary.“Notwithstanding the evidence based guidelines, their final acceptation requires unrestricted discussion and consideration of differences in clinical practice and experience between countries”.

Occurrence of phaeochromocytoma tumours in RET mutation carriers - a single-centre study.

INTRODUCTION Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant genetic syndrome caused by germline mutation in RET proto-oncogene. The most common mutations are in a cysteine rich domain. Phaeochromocytoma will develop in approximately 50% of RET proto-oncogene carriers. MATERIAL AND METHODS The studied population consisted of 228 RET proto-oncogene mutation carriers. Monitoring for the diagnosis of phaeochromocytoma was carried out in all patients with established genetic status. Mean time of follow up was 138 months. Surveillance consisted of periodically performed clinical evaluation, 24-hour urinary determinations of total metanephrines complementary with imaging (CT, MR, MIBG scintigraphy). RESULTS Phaeochromocytoma developed in 41 patients (18% of all RET proto-oncogene mutations carriers). The mean age of diagnosis for the whole cohort was 43 years. In eight cases phaeochromocytoma was the first manifestation of the MEN 2 syndrome. Only eight (20%) patients were symptomatic at diagnosis of phaeochromocytoma. The mean size of the tumour was 4.3 cm. There was no extra-adrenal localisation. We observed one case of malignant phaeochromocytoma. CONCLUSIONS In patients with MEN 2 syndrome phaeochromocytomas are usually benign adrenal tumours with high risk of bilateral development. Taking to account the latter risk and non-specific clinical manifestation of the neoplasm it is mandatory to screen all RET proto-oncogene mutations carriers for phaeochromocytoma.

Ongoing risk stratification for differentiated thyroid cancer (DTC) - stimulated serum thyroglobulin (Tg) before radioiodine (RAI) ablation, the most potent risk factor of cancer recurrence in M0 patients.

INTRODUCTION Adequate postoperative risk assessment currently constitutes the principle of DTC treatment and further management. The aim of the study - a retrospective assessment of risk factors influencing DTC relapse. MATERIAL AND METHODS The study group consisted of 510 DTC staged pT1b-T4N0-N1M0, in whom total thyroidectomy and complementary radioiodine (RAI) treatment were carried out. In 71% papillary thyroid cancer was diagnosed, whereas in the remaining 29% - follicular thyroid carcinoma. Based on TNM classification from 1997, T1 feature was diagnosed in 11.6%, T2 in 35.1%, T3 in 8.4%, T4 in 9,4%, while in 35.5% - Tx. Lymph node metastases were present in 24.7% of cases. Median follow-up was 12.1 years (1.5-15.2). RESULTS Age at DTC diagnosis, tumour diameter (T), lymph node metastases (N1), stimulated thyroglobulin, and RAI uptake in thyroid bed at qualification for RAI ablation significantly influenced freedom from progression time (FFP) in a multivariate analysis. When postoperative stimulated Tg was > 30 ng/mL the risk of relapse increased nearly six-fold, whereas the presence of N1 feature - four-fold. The total risk of relapse in the whole group was 12.55% while median FFP was 154.8 months. Five-year and 10-year FFP was 90.1% and 87.5%, respectively. CONCLUSIONS Postoperative stimulated thyroglobulin level was the most potent, independent risk factor influencing FFP in DTC patients. Age above 60 years, an initial DTC stage (T and N features), and low RAI uptake in thyroid bed ( < 1%) were related to a higher risk of DTC relapse, whereas the investigated histopathological features were insignificant.

Gender-dependent and age-of-onset-specific association of the rs11675434 single-nucleotide polymorphism near TPO with susceptibility to Graves’ ophthalmopathy

The role of TPO gene polymorphism in the susceptibility to Graves’ disease (GD) remains unclear. However, single-nucleotide polymorphisms (SNPs) near TPO have been recently associated with serum levels of thyroid peroxidase (TPO) antibody in two independent genome-wide association studies. Moreover, we have observed a strong association between the rs11675434 SNP located near TPO and the presence of clinically evident Graves’ ophthalmopathy (GO). The aim of the current study was to reevaluate and dissect this association in an extended group of 1231 well-characterized patients with GD (1043 adults and 188 children) and 1130 healthy controls from the Polish Caucasian population, considering possible gender-dependent and age-of-onset-specific effects of the studied SNP. We found that the T allele of rs11675434 was significantly more frequent in GD patients with than without GO (odds ratio (OR)=1.26, 95% confidence interval (CI)=1.05–1.51, P=0.012), which was consistent with our previous findings. Further analyses performed in subgroups of patients showed that the association with GO was significant in adult patients with age of GD onset ⩾45 years (OR=1.34, 95% CI=1.03–1.75, P=0.031), but not in children and adolescents or adult patients with earlier onset of the disease (OR=1.72, 95% CI=0.77–3.84, P=0.18 and OR=1.05, 95% CI=0.79–1.40, P=0.75, respectively). Moreover, a strong association with GO was present in males (OR=2.06, 95% CI=1.40–3.02, P=0.0002), whereas it was absent in females (OR=1.10, 95% CI=0.90–1.35, P=0.35). The results of our study further suggest that rs11675434 SNP located near TPO is associated with the development of GO, especially in males and patients with later age of GD onset.

Coexistence of TERT Promoter Mutations and the BRAF V600E Alteration and Its Impact on Histopathological Features of Papillary Thyroid Carcinoma in a Selected Series of Polish Patients

TERT promoter (TERTp) mutations are important factors in papillary thyroid carcinomas (PTCs). They are associated with tumor aggressiveness, recurrence, and disease-specific mortality and their use in risk stratification of PTC patients has been proposed. In this study we investigated the prevalence of TERTp mutations in a cohort of Polish patients with PTCs and the association of these mutations with histopathological factors, particularly in coexistence with the BRAF V600E mutation. A total of 189 consecutive PTC specimens with known BRAF mutational status were evaluated. TERTp mutations were detected in 8.5% of cases (16/189) with the C228T mutation being the most frequent. In six of the PTC specimens (3.2%), four additional TERTp alterations were found, which included one known polymorphism (rs2735943) and three previously unreported alterations. The association analysis revealed that the TERTp hotspot mutations were highly correlated with the presence of the BRAF V600E mutation and their coexistence was significantly associated with gender, advanced patient age, advanced disease stage, presence of lymph node metastases, larger tumor size, and tumor-capsule infiltration. While correlations were identified, the possibility of TERTp mutations being key molecular modulators responsible for PTC aggressiveness requires further studies.

131-I MIBG therapy of malignant pheochromocytoma and paraganglioma tumours — a single-centre study

INTRODUCTION Pheochromocytomas and paragangliomas are rare tumors deriving from chromaffin cells of adrenal medulla or paraganglia. They are usually benign but 10-35% of them present malignant behavior. The aim of the study was to evaluate the efficacy and safety of 131-I MIBG therapy in malignant pheochromocytoma /paraganglioma patients (MPPGL). MATERIAL AND METHODS 18 patients (7 women and 11 men) were included in this study. Between 2002 and 2016 they underwent 131-I MIBG therapy because of MPPGL and their medical data were analyzed retrospectively. Clinical indications for the treatment included progressive disease or massive tissue involvement independently from disease progression. Tumor response for the first time was assessed 3 months after the last treatment according to Response Evaluation Criteria in Solid Tumors criteria and by 131-I MIBG scans. RESULTS The mean single dose used was 7.25 GBq (196 mCi) and mean cumulative dose 33.08 GBq ( 894 mCi). In 2 (11%) patients complete tumor response was achieved. In 1 (6%) patient partial response was obtained. In 13 (72%) patients stable disease was observed. In 2 (11%) patients progression was diagnosed three months after treatment discontinuation. In the whole studied group the progression free survival time was 85 months and overall 5-year survival was 87%. CONCLUSIONS Radionuclide treatment with use of 131-I MIBG may be effective form of palliative treatment for patients with inoperative neoplasm spread, progressive disease or patients requiring alleviation of symptoms. < p > < /p >.

Comparison of clinical examination with orbital MRI evaluation in patients with thyroid orbitopathy - do we need imaging and when?

The frequency of Graves’ orbitopathy (GO) in patients with Graves’ disease (GD) depends on the method of assessment. Diagnosis based on clinical symptoms is made in about 30-50% patients, more often (70%) after ophtalmological examination with evaluation of intraocular pressure, whereas MRI reveals GO in up to 90%. Proper identification of active phase of the disease is crucial.