Metastatic duodenopancreatic neuro-endocrine tumors (dpNETs) are the most important disease-related cause of death in patients with multiple endocrine neoplasia type 1 (MEN1). Nonfunctioning pNETs (NF-pNETs) are highly prevalent in MEN1 and clinically heterogeneous. Therefore, management is controversial. Data on prognostic factors for risk stratification are limited. This systematic review aims to establish the current state of evidence regarding prognostic factors in MEN1-related NF-pNETs. We systematically searched four databases for studies assessing prognostic value of any factor on NF-pNET progression, development of distant metastases, and/or overall survival. In- and exclusion, critical appraisal and data-extraction were performed independently by two authors according to pre-defined criteria. Thirteen studies (370 unique patients) were included. Prognostic factors investigated were tumor size, timing of surgical resection, WHO grade, methylation, p27/p18 expression by immunohistochemistry (IHC), ARX/PDX1 IHC and alternative lengthening of telomeres. Results were complemented with evidence from studies in MEN1-related pNET for which data could not be separately extracted for NF-pNET and data from sporadic NF-pNET. We found that the most important prognostic factors used in clinical decision making in MEN1-related NF-pNETs are tumor size and grade. NF-pNETs <2 cm may be managed with watchful waiting, while surgical resection is advised for NF-pNETs ≥2 cm. Grade 2 NF-pNETs should be considered high risk. The most promising and MEN1-relevant avenues of prognostic research are multi-analyte circulating biomarkers, tissue-based molecular factors and imaging-based prognostication. Multi-institutional collaboration between clinical, translation and basic scientists with uniform data and biospecimen collection in prospective cohorts should advance the field.
S M Sadowski, C R C Pieterman, N D Perrier, F Triponez, and G D Valk
Giancarlo Di Giuseppe, Aleksandra M Zuk, Jonathan D Wasserman, and Jason D Pole
Differentiated thyroid carcinoma (DTC) in children, adolescents, and young adults is associated with excellent prognosis. However, little is known about the long-term utilization of healthcare resources among survivors. The objective of this study was to compare the utilization of healthcare resources among DTC survivors to the general population, with a focus on pulmonary-related resource utilization. Population-based linked data were used to retrospectively ascertain DTC patients from the Ontario Cancer Registry, age <30 years at diagnosis between 1992 and 2011. DTC cases were individually matched 1:10 to the general population on age, sex, diagnosis year, and rural status. Billing records for all-cause hospitalizations, emergency department visits, pulmonary subspecialist visits, and chest imaging were compared using incidence rate ratios (IRR). A total of 2456 individuals with DTC were identified, with women representing the majority (82.8%) of cases. Compared to controls, hospitalization and emergency department visit IRRs were 2.56 (95% CI, 2.49–2.63) and 2.22 (95% CI, 2.18–2.26), respectively. An excess of pulmonary diagnostic imaging was observed for chest radiography (IRR, 2.7; 95% CI, 2.6–2.8) and pulmonary CT’s (IRR, 17.5; 95% CI, 15.8–19.3). Patients who underwent radioactive iodine therapy had a higher incidence of pulmonary-related healthcare utilization than those who did not. The highest healthcare utilization for all modalities was observed in the 30 to 90 days after DTC diagnosis with a steady decline further from diagnosis; however, elevated utilization was observed throughout the observation period. Health services utilization is high for primary DTC survivors, irrespective of the time since diagnosis. Radioactive iodine therapy is associated with higher rates of utilization. These findings have ramifications for treatment, surveillance and for policy formulation.
Alfred King-yin Lam
The aim is to review the features of 117 primary squamous cell carcinomas of thyroid which meet the histological criteria of the World Health Organization classification of endocrine tumours. The carcinomas occur in 83 women and 34 men (female to male ratio is 2.4 to 1) and with median age at presentation of 64. Half of these squamous cell carcinomas of thyroid were moderately differentiated. PAX-8 protein is a sensitive marker for confirming the thyroid origin of the carcinoma. The carcinoma is also positive for p63, p40, cytokeratins 5/6, 7,19 and negative for cytokeratins 20 and 10/13. P53 overexpression is common. The most important differential diagnosis is direct infiltration or metastatic involvement by squamous cell carcinoma from other organs. Limited mutation analysis revealed BRAF mutation in some squamous cell carcinomas of the thyroid. The genetic profile appears to be different from anaplastic thyroid carcinomas. Primary squamous cell carcinoma of thyroid had lymph node involvement in 59% and distant metastases in 26%. The median survival of the patients was 8 months. Curative surgery offers the best survival for the patients with the carcinoma. To conclude, primary squamous cell carcinoma of the thyroid gland has distinctive clinical, pathological and molecular profiles. It is important to recognize this unique variant of thyroid carcinoma for possible curative surgical resection and to do more genomic works on the entity to uncover the molecular pathogenesis.
Olimpia Alice Manzardo, Miriam Cellini, Rita Indirli, Alessia Dolci, Paolo Colombo, Flaminia Carrone, Elisabetta Lavezzi, Giovanna Mantovani, Gherardo Mazziotti, Maura Arosio, and Andrea Gerardo Antonio Lania
TNM 8th edition introduces changes in the staging of patients with differentiated thyroid carcinoma (DTC). This study aims at assessing the value of TNM 8th edition in predicting response to therapy and structural recurrence of DTC. Four hundred and eighty DTC patients were retrospectively evaluated by 7th and 8th editions of TNM staging system in relationship with risk stratification, response to therapy and recurrence of disease as defined by 2015 ATA guidelines. As compared to the 7th edition, TNM 8th led to downstage 136 patients (28.3%), with 97.5% of patients falling into lower stages (I–II) and only 2.5% remaining in higher stages (III–IV) (P < 0.001). Patients who were downstaged in stages I–II by TNM 8th were classified more frequently at intermediate-high risk (P < 0.001), had more frequently structural incomplete response to therapy (P = 0.009) and had higher risk of structural recurrence (P = 0.002) as compared to patients who were in the same TNM stages but were not downstaged. Specifically, the risk of structural recurrence was significantly higher in patients in whom the downstaging was induced by changes in tumour classification (hazard ratio (HR) 6.18, 95% CI 2.20–17.40; P = 0.001) but not in those who were downstaged for the increase in age cut-off (HR 2.80, 95% CI 0.86–9.19; P = 0.09). In conclusion, TNM 8th edition did not show reliability in predicting aggressiveness of DTC. In fact, the downstaging of DTC patients especially when performed due to changes in tumour classification may overlook patients predisposed to structural recurrence, potentially causing uncertainty in the therapeutic decision-making at the time of disease’s diagnosis.
James F Powers, Brent Cochran, James D Baleja, Hadley D Sikes, Andrew D Pattison, Xue Zhang, Inna Lomakin, Annette Shepard-Barry, Karel Pacak, Sun Jin Moon, Troy F Langford, Kassi Taylor Stein, Richard W Tothill, Yingbin Ouyang, and Arthur S Tischler
Tumors caused by loss-of-function mutations in genes encoding TCA cycle enzymes have been recently discovered and are now of great interest. Mutations in succinate dehydrogenase (SDH) subunits cause pheochromocytoma/paraganglioma (PCPG) and syndromically associated tumors, which differ phenotypically and clinically from more common SDH-intact tumors of the same types. Consequences of SDH deficiency include rewired metabolism, pseudohypoxic signaling and altered redox balance. PCPG with SDHB mutations are particularly aggressive, and development of treatments has been hampered by lack of valid experimental models. Attempts to develop mouse models have been unsuccessful. Using a new strategy, we developed a xenograft and cell line model of SDH-deficient pheochromocytoma from rats with a heterozygous germline Sdhb mutation. The genome, transcriptome and metabolome of this model, called RS0, closely resemble those of SDHB-mutated human PCPGs, making it the most valid model now available. Strategies employed to develop RS0 may be broadly applicable to other SDH-deficient tumors.
H H Milioli, S Alexandrou, E Lim, and C E Caldon
Cyclin E1 is one the most promising biomarkers in estrogen receptor positive (ER+) breast cancer for response to the new standard of care drug class, CDK4/6 inhibitors. Because of its strong predictive value, cyclin E1 expression may be used in the future to triage patients into potential responders and non-responders. Importantly, cyclin E1 is highly related to cyclin E2, and both cyclin E1 and cyclin E2 are estrogen target genes that can facilitate anti-estrogen resistance and can be highly expressed in breast cancer. However cyclin E1 and E2 are often expressed in different subsets of patients. This raises questions about whether the expression of cyclin E1 and cyclin E2 have different biological drivers, if high expressing subsets represent different clinical subtypes, and how to effectively develop a biomarker for E-cyclin expression. Finally, several pan-CDK inhibitors that target cyclin E-CDK2 activity have reached Phase II clinical trials. In this review, we outline the data identifying that different cohorts of patients have high expression of cyclins E1 and E2 in ER+ cancer and address the implications for biomarker and therapeutic development.
Claudio Ricci, Stefano Partelli, Carlo Ingaldi, Valentina Andreasi, Davide Campana, Francesca Muffatti, Laura Alberici, Cecilia Giorgi, Riccardo Casadei, and Massimo Falconi
Overall survival (OS) is considered as the standard measure of outcome in oncology. However, considering that resectable pancreatic neuroendocrine neoplasms (Pan-NENs) usually have a long OS, the feasibility of prospective studies is questionable due to a long follow-up period needed. The primary endpoint was to validate the use of disease-free survival (DFS) as a surrogate measure of OS. The secondary endpoint was to calculate the gain in sample size using DFS instead of OS in hypothetical prospective studies with two parallel groups. A systematic review of studies reporting both OS and DFS in resected Pan-NENs was carried out. Multivariate linear regression analysis was used to evaluate if DFS predicts the OS in patients undergoing radical resection. Monte Carlo simulation was performed to estimate the gain in sample size, supposing the use of DFS instead of OS, to evaluate a hypothetical adjuvant treatment after surgery in a randomized trial. Six studies reporting data about seven cohorts of resected Pan-NENs were included, for a total of 1088 patients. The median OS and DFS were 144 (27–134) and 122 (50–267) months, respectively. There was a significant correlation between DFS and OS (R 2 = 0.988; P = 0.035). Monte Carlo simulations showed that the number of patients needed to demonstrate a significant reduction of probability of a ‘target event’ in a hypothetical two-arm group exploring the hypothetical role of adjuvant therapy was reduced using DFS instead OS. This finding supports the legitimacy of using DFS as an acceptable surrogate for OS in surgical clinical trials.
Johan O Paulsson, Na Wang, Jiwei Gao, Adam Stenman, Jan Zedenius, Ninni Mu, Weng-Onn Lui, Catharina Larsson, and C Christofer Juhlin
Mutations in the miRNA enzyme gene DICER1 have been reported in several endocrine malignancies and is associated with the rare tumour-predisposing DICER1 syndrome. DICER1 mutations have been reported in subsets of follicular thyroid carcinoma (FTC), but the role of DICER1 in follicular thyroid tumorigenesis has not been extensively studied. In this study, we investigate the role of DICER1 in 168 follicular thyroid tumours and in an FTC cell line. We found rare DICER1 mutations in paediatric FTC cases and a general DICER1 down-regulation in FTCs visualized both on mRNA and protein level, especially pronounced in Hürthle cell carcinoma (HuCC). The down-regulation was also evident in follicular thyroid adenomas (FTAs), suggesting a potential early step in tumorigenesis. The expression of DICER1 was lower in FTCs of older patients in which TERT promoter mutations are more frequent. In FTCs, DICER1 down-regulation was not caused by gene copy number loss but significantly correlated to expression of the transcription factor GABPA in clinical cases. GABPA was found to bind to the DICER1 promoter and regulate DICER1 expression in vitro, as GABPA depletion in FTC cell lines reduced DICER1 expression. This in turn stimulated cell proliferation and affected the miRNA machinery, evident by altered miRNA expression. To conclude, we show that GABPA directly regulates DICER1 in FTC, acting as a tumour suppressor and displaying down-regulation in clinical samples. We also show reduced expression of DICER1 in benign and malignant follicular thyroid tumours, suggesting a potentially early tumorigenic role of this gene aberrancy.
Eyun Song, Dong Eun Song, Jonghwa Ahn, Tae Yong Kim, Won Bae Kim, Young Kee Shong, Min Ji Jeon, and Won Gu Kim
Major clinical challenges exist with differentiated thyroid cancers with distant metastases or rare but aggressive types, such as poorly differentiated thyroid carcinomas and anaplastic thyroid carcinomas. The precise characterization of the mutational profile in these advanced thyroid cancers is crucial. Samples were collected from primary tumors and distant metastases of 64 patients with distant metastases from differentiated thyroid cancer, poorly differentiated thyroid carcinoma, or anaplastic thyroid carcinoma. Targeted next-generation sequencing was performed with 50 known thyroid-cancer-related genes. Of the 82 tissues, 63 were from primary tumors and 19 from distant metastases. The most prevalent mutation observed from the primary tumors was TERT promoter mutation (56%), followed by BRAF (41%) and RAS (24%) mutations. TP3 was altered by 11%. Mutations in histone methyltransferases, SWI/SNF subunit–related genes, and PI3K/AKT/mTOR pathway-related genes were present in 42%, 12%, and 22%, respectively. When the mutational status was analyzed in 15 matched pairs of thyroid tumors and their matched distant metastases and one pair of distant metastases with two distinct sites, the concordance was high. A similar frequency of mutations in TERT promoter (58%) and BRAF (42%) as well as histone methyltransferases (37%), SWI/SNF subunits (10%), and PI3K/AKT/mTOR pathway (26%) were noted. The same main, early and late mutations were practically always present in individual primary tumor–metastasis pairs. Enrichment of TERT promoter, BRAF, and RAS mutations were detected in highly advanced thyroid cancers with distant metastasis. The genetic profiles of primary thyroid tumors and their corresponding distant metastases showed a high concordance.
Camille Buffet, Johanna Wassermann, Fabio Hecht, Laurence Leenhardt, Corinne Dupuy, Lionel Groussin, and Charlotte Lussey-Lepoutre
The management of radioiodine refractory thyroid cancers (RAIR TC) is challenging for the clinician. Tyrosine kinase inhibitors classically prescribed in this setting can fail due to primary or acquired resistance or the necessity of drug withdrawal because of serious or moderate but chronic and deleterious adverse effects. Thus, the concept of redifferentiation strategy, which involves treating patients with one or more drugs capable of restoring radioiodine sensitivity for RAIR TC, has emerged. The area of redifferentiation strategy leads to the creation of new definitions of RAIR TC including persistent non radioiodine-avid patients and ‘true’ RAIR TC patients. The latter group presents a restored or increased radioiodine uptake in metastatic lesions but with no radiological response on conventional imaging, that is, progression of a metastatic disease, thus proving that they are ‘truly’ resistant to the radiation delivered by radioiodine. Unlike these patients, metastatic TC patients with restored radioiodine uptake offer the hope of prolonged remission or even cure of the disease as for radioiodine-avid metastatic TC. Here, we review the different redifferentiation strategies based on the underlying molecular mechanism leading to the sodium iodide symporter (NIS) and radioiodine uptake reinduction, that is, by modulating signaling pathways, NIS transcription, NIS trafficking to the plasma membrane, NIS post-transcriptional regulation, by gene therapy and other potential strategies. We discuss clinical trials and promising preclinical data of potential future targets.