Activating mutations of the RET proto-oncogene are associated with inherited syndromes, multiple endocrine neoplasia (MEN2A/2B) and with familial and sporadic medullary thyroid cancer (MTC). Single base pair missense mutations in the extracellular Cys-rich domain are responsible for most MEN2A and familial MTC (FMTC) cases. Rarely, somatic deletions and germline duplications have been described in sporadic MTC and in FMTC. We report the detection and functional studies of a deletion/insertion in exon 11 (c.2646delGinsTTCT) associated with FMTC. This in-frame complex rearrangement leads to an Asn to Lys change (Lys666Asn) and to a Ser insertion. The mutation was found in the proband, who was diagnosed with metastatic MTC at 41 years, and in her son, who presented diffuse C-cells hyperplasia at 4 years of age. The mutation displayed a transforming activity stronger than Ret wild type (Ret-WT) at the focus formation assay and functional analyses after transient and stable transfection revealed an increased autophosphorylation, indicating the constitutive activation of the receptor. The transforming activity may be favoured by an increased stabilization of the fully mature form of the mutant receptor. Dimerization assay demonstrated that the activation mechanism of the complex mutation is not mediated by stable dimer formation. Computational analysis predicted nonconservative alterations in the mutant protein consistent with a possible modification of the conformation of the receptor. In conclusion, the first molecular studies on a complex germline RET mutation lying in the juxtamembrane region of the receptor are reported. Functional analyses showed that alterations at this level too can lead to a ligand independent Ret activation.
Daniela Cordella, Marina Muzza, Luisella Alberti, Paolo Colombo, Pietro Travaglini, Paolo Beck-Peccoz, Laura Fugazzola, and Luca Persani
Uberta Verga, Stefano Ferrero, Leonardo Vicentini, Tatiana Brambilla, Valentina Cirello, Marina Muzza, Paolo Beck-Peccoz, and Laura Fugazzola
The cut-off values able to differentiate between reactive or neoplastic C-cell hyperplasia (CCH) or to predict sporadic medullary thyroid cancer (MTC) are still debated both for basal and stimulated calcitonin (bCT and sCT). In the present study, the prevalence and the histological patterns of CCH in 15 patients with multinodular goiter (MNG), bCT>10 pg/ml and sCT levels >50 pg/ml were studied. As controls, 16 patients with MNG and bCT levels <10 pg/ml and 4 patients with familial (FMTC) were included. For each case, calcitonin (CT) immunoreactive cells were counted in 60 consecutive high-power fields (400×) and CCH classified as focal, diffuse, nodular, or neoplastic. RET genetic analyses were performed at the germline and tissue levels in MTC and CCH cases. In patients with MNG, sCT levels >50 pg/ml were associated with CCH or MTC, being the total number of C-cells/60 fields significantly higher than that found in MNG with normal bCT (P = 0.0008) and comparable with that detected in FMTCs. In the group with sCT>50 pg/ml, the C-cells displayed a neoplastic phenotype. Neither germline nor somatic RET mutations were found. In conclusion, sCT levels >50 pg/ml were always associated with CCH, without correlation between CT levels and the number of C-cells or the final diagnosis. The C-cells had a morphology and distribution pattern similar to those observed in FMTC. Thus, sCT levels >50 pg/ml indicate the presence of CCH with a possible preneoplastic potential, suggesting the opportunity to perform a prophylactic surgical treatment.
Simone De Leo, Michela Perrino, Sara Badiali, Stefania Rossi, Valentina Cirello, Carla Colombo, Delfina Tosi, Gianmaria Cantoni, Luca Poggi, Gaetano Bulfamante, Paolo Beck-Peccoz, Leonardo Vicentini, and Laura Fugazzola
Michela Perrino, Guia Vannucchi, Leonardo Vicentini, Gianmaria Cantoni, Davide Dazzi, Carla Colombo, Marcello Rodari, Arturo Chiti, Paolo Beck-Peccoz, and Laura Fugazzola
The incidence of papillary thyroid cancer (PTC) is rapidly growing, the recorded increase being mainly related to tumors ≤2 cm. The re-classification of tumors >1 and ≤2 cm limited to the thyroid from the T2 to the T1 category triggered some concerns about their best management. In order to identify possible predictors of disease outcome, several clinico-pathological features were analyzed by uni- and multivariate analyses in a retrospective consecutive series of 251 PTCs ≤2 cm. Moreover, since 37% of cases were submitted to prophylactic central compartment node dissection (CLND, VI–VII levels) and radioiodine ablation was performed only when the tumor had an extrathyroidal extension, the impact of these therapeutic tools on the final outcome was evaluated. Among all outcome predictors analyzed, only lymph node metastases and extracapsular invasion were strongly associated with persistence/recurrence. It is worth noting that neither age nor tumor size was a significant indicator of the outcome. Interestingly, as far as the therapeutic interventions are concerned, CLND was strongly associated with remission, whereas radioiodine ablation did not influence the outcome. In conclusion, present results confirm the prognostic influence of node metastases and extra-thyroidal invasion, indicating the need for aggressive treatment in tumors extending beyond the capsule. On the contrary, all pT1N0 tumors, regardless of the diameter, the number of intrathyroidal foci, and the age can be effectively treated only by surgery. The major impact of prophylactic CLND on prognosis suggests to routinely associate it to total thyroidectomy in cases with a preoperative diagnosis of malignancy.
Carla Colombo, Marina Muzza, Gabriele Pogliaghi, Sonia Palazzo, Guia Vannucchi, Leonardo Vicentini, Luca Persani, Giacomo Gazzano, and Laura Fugazzola
Cytology is the gold standard method for the differential diagnosis of thyroid nodules, though 25–30% of them are classified as indeterminate. We aimed to set up a ‘thyroid risk score’ (TRS) to increase the diagnostic accuracy in these cases. We prospectively tested 135 indeterminate thyroid nodules. The pre-surgical TRS derived from the sum of the scores assigned at cytology, EU-TIRADS classification, nodule measurement, and molecular characterization, which was done by our PTC-MA assay, a customized array able to cost-effectively evaluate 24 different genetic alterations including point mutations and gene fusions. The risk of malignancy (ROM) increased paralleling the score: in the category >4 and ≤ 6 (low suspicion), >6 ≤ 8 (intermediate suspicion), and >8 (high suspicion); ROM was 10, 47 and 100%, respectively. ROC curves selected the score >6.5 as the best threshold to differentiate between malignant and benign nodules (P < 0.001). The TRS > 6.5 had a better performance than the single parameters evaluated separately, with an accuracy of 77 and 82% upon inclusion of noninvasive follicular thyroid neoplasm with papillary-like nuclear features among malignant or benign cases, respectively. In conclusion, for the first time, we generated a score combining a cost-effective molecular assay with already validated tools, harboring different specificities and sensitivities, for the differential diagnosis of indeterminate nodules. The combination of different parameters reduced the number of false negatives inherent to each classification system. The TRS > 6.5 was highly suggestive for malignancy and retained a high accuracy in the identification of patients to be submitted to surgery.
Francis Worden, Martin Fassnacht, Yuankai Shi, Tatiana Hadjieva, Françoise Bonichon, Ming Gao, Laura Fugazzola, Yuichi Ando, Yasuhisa Hasegawa, Do Joon Park, Young Kee Shong, Johannes W A Smit, John Chung, Christian Kappeler, Gerold Meinhardt, Martin Schlumberger, and Marcia S Brose
Effective adverse event (AE) management is critical to maintaining patients on anticancer therapies. The DECISION trial was a multicenter, randomized, double-blind, placebo-controlled, Phase 3 trial which investigated sorafenib for treatment of progressive, advanced, or metastatic radioactive iodine-refractory, differentiated thyroid carcinoma. Four hundred and seventeen adult patients were randomized (1:1) to receive oral sorafenib (400 mg, twice daily) or placebo, until progression, unacceptable toxicity, noncompliance, or withdrawal. Progression-free survival, the primary endpoint of DECISION, was reported previously. To elucidate the patterns and management of AEs in sorafenib-treated patients in the DECISION trial, this report describes detailed, by-treatment-cycle analyses of the incidence, prevalence, and severity of hand–foot skin reaction (HFSR), rash/desquamation, hypertension, diarrhea, fatigue, weight loss, increased serum thyroid stimulating hormone, and hypocalcemia, as well as the interventions used to manage these AEs. By-cycle incidence of the above-selected AEs with sorafenib was generally highest in cycle 1 or 2 then decreased. AE prevalence generally increased over cycles 2–6 then stabilized or declined. Among these AEs, only weight loss tended to increase in severity (from grade 1 to 2) over time; severity of HFSR and rash/desquamation declined over time. AEs were mostly grade 1 or 2, and were generally managed with dose interruptions/reductions, and concomitant medications (e.g. antidiarrheals, antihypertensives, dermatologic preparations). Most dose interruptions/reductions occurred in early cycles. In conclusion, AEs with sorafenib in DECISION were typically grade 1 or 2, occurred early during the treatment course, and were manageable over time.
Paola Romeo, Carla Colombo, Roberta Granata, Giuseppina Calareso, Ambra Vittoria Gualeni, Matteo Dugo, Loris De Cecco, Maria Grazia Rizzetti, Angela Zanframundo, Antonella Aiello, Maria Luisa Carcangiu, Annunziata Gloghini, Stefano Ferrero, Lisa Licitra, Angela Greco, Laura Fugazzola, Laura Deborah Locati, and Maria Grazia Borrello
This study aimed to identify circulating miRNAs as novel non-invasive biomarkers for prognosis and vandetanib response in advanced medullary thyroid cancer (MTC) patients. We prospectively recruited two independent cohorts of locally advanced/metastatic MTC patients including a subgroup of vandetanib-treated subjects: a discovery cohort (n = 20), including matched plasma/tissue samples (n = 17/20), and a validation cohort, yielding only plasma samples (n = 17). Plasma samples from healthy subjects (n = 36) and MTC patients in remission (n = 9) were used as controls. MTC (n = 17 from 8 patients included in discovery cohort) and non-neoplastic thyroid specimens (n = 3) were assessed by microarray profiling to identify candidate circulating miRNAs. qRT-PCR and in situ hybridization were carried out to validate the expression and localization of a selected miRNA within tissues, and qRT-PCR was also performed to measure miRNA levels in plasma samples. By microarray analysis, we identified 51 miRNAs differentially expressed in MTC. The most overexpressed miR, miR-375, was highly expressed by C cells compared to other thyroid cells, and more expressed in MTC than in reactive C-cell hyperplasia. MTC patients had significantly higher miR-375 plasma levels than healthy controls (P < 0.0001) and subjects in remission (P = 0.0004) as demonstrated by qRT-PCR analysis. miR-375 plasma levels were not predictive of vandetanib response, but, notably, high levels were associated with significantly reduced overall survival (HR 10.61, P < 0.0001) and were a strong prognostic factor of poor prognosis (HR 6.24, P = 0.00025) in MTC patients. Overall, our results unveil plasma miR-375 as a promising prognostic marker for advanced MTC patients, to be validated in larger cohorts.