The Long Journey towards Personalized Targeted Therapy in Poorly Differentiated Thyroid Carcinoma (PDTC): A Case Report and Systematic Review.

BACKGROUND: Poorly differentiated thyroid carcinoma (PDTC) has an intermediate prognosis between indolent well-differentiated thyroid carcinoma (TC) and anaplastic carcinoma. Herein, we present a case report with a PDTC component, along with a systematic review of the literature. CASE REPORT: We report a case of a 45-year-old man diagnosed with a PDTC component, along with hobnail and tall-cell variant features positive for BRAFV600E mutation, after a total thyroidectomy and neck dissection. Radioactive iodine (RAI)-131 therapy was applied, but an early recurrence led to complementary surgeries. The anti-Tg rise, the presence of new lymph nodes, and the negative whole-bodyradioiodine scan were suggestive of a radioiodine-resistant tumor. Lenvatinib, sorafenib, dabrafenib/trametinib, cabozantinib and radiotherapy were all administered, controlling the tumor for a period of time before the patient ultimately died post-COVID infection. Systematic Review: We searched PubMed, Scopus, and WebofScience to identify studies reporting clinicopathological characteristics, molecular marker expression, and management of non-anaplastic TC with any proportion of PDTC in adult patients. Of the 2007 records retrieved, 82were included in our review (PROSPERO-ID545847). CONCLUSIONS: Our case, together with the systematic review, imply that a combination of molecular-targetedtreatments may be safe and effective in patients with RAI-resistantBRAF-mutated advanced PDTC when surgery has failed to control tumor progression.

Genomic and immune landscape Of metastatic pheochromocytoma and paraganglioma.

The mechanisms triggering metastasis in pheochromocytoma/paraganglioma are unknown, hindering therapeutic options for patients with metastatic tumors (mPPGL). Herein we show by genomic profiling of a large cohort of mPPGLs that high mutational load, microsatellite instability and somatic copy-number alteration burden are associated with ATRX/TERT alterations and are suitable prognostic markers. Transcriptomic analysis defines the signaling networks involved in the acquisition of metastatic competence and establishes a gene signature related to mPPGLs, highlighting CDK1 as an additional mPPGL marker. Immunogenomics accompanied by immunohistochemistry identifies a heterogeneous ecosystem at the tumor microenvironment level, linked to the genomic subtype and tumor behavior. Specifically, we define a general immunosuppressive microenvironment in mPPGLs, the exception being PD-L1 expressing MAML3-related tumors. Our study reveals canonical markers for risk of metastasis, and suggests the usefulness of including immune parameters in clinical management for PPGL prognostication and identification of patients who might benefit from immunotherapy.

Initial clinical and treatment patterns of advanced differentiated thyroid cancer: ERUDIT study.

Background: Up to 30% of differentiated thyroid cancer (DTC) will develop advanced-stage disease (aDTC) with reduced overall survival (OS). Objective: The aim of this study is to characterize initial diagnosis of aDTC, its therapeutic management, and prognosis in Spain and Portugal. Methods: A multicentre, longitudinal, retrospective study of adult patients diagnosed with aDTC in the Iberian Peninsula was conducted between January 2007 and December 2012. Analyses of baseline characteristics and results of initial treatments, relapse- or progression-free survival ((RP)FS) from first DTC diagnosis, OS, and prognostic factors impacting the evolution of advanced disease were evaluated. Results: Two hundred and thirteen patients (median age: 63 years; 57% female) were eligible from 23 hospitals. Advanced disease presented at first diagnosis (de novo aDTC) included 54% of patients, while 46% had relapsed from early disease (recurrent/progressive eDTC). At initial stage, most patients received surgery (98%) and/or radioiodine (RAI) (89%), with no differences seen between median OS (95% CI) (10.4 (7.3-15.3) years) and median disease-specific-survival (95% CI) (11.1 (8.7-16.2) years; log-rank test P = 0.4737). Age at diagnosis being <55 years was associated with a lower risk of death (Wald chi-square (Wc-s) P < 0.0001), while a poor response to RAI to a higher risk of death ((Wc-s) P < 0.05). In the eDTC cohort, median (RP)FS (95% CI) was of 1.7 (1.0-2.0) years after RAI, with R0/R1 surgeries being the only common significant favourable factor for longer (RP)FS and time to aDTC ((Wc-s) P < 0.05). Conclusion: Identification of early treatment-dependent prognostic factors for an unfavourable course of advanced disease is possible. An intensified therapeutic attitude may reverse this trend and should be considered in poor-performing patients. Prospective studies are required to confirm these findings.

Pasireotide in the Personalized Treatment of Acromegaly.

The delay in controlling the disease in patients who do not respond to first-line treatment with first generation somatostatin receptor ligands (first-generation SRLs) can be quantified in years, as every modification in the medical therapy requires some months to be fully evaluated. Considering this, acromegaly treatment should benefit from personalized medicine therapeutic approach by using biomarkers identifying drug response. Pasireotide has been positioned mostly as a compound to be used in first-generation SRLs resistant patients and after surgical failure, but sufficient data are now available to indicate it is a first line therapy for patients with certain characteristics. Pasireotide has been proved to be useful in patients in which hyperintensity T2 MRI signal is shown and in those depicting low SST2 and high expression of SST5, low or mutated AIP condition and sparsely granulated immunohistochemical pattern. This combination of clinical and pathological characteristics is unique for certain patients and seems to cluster in the same cases, strongly suggesting an etiopathogenic link. Thus, in this paper we propose to include this clinico-pathologic phenotype in the therapeutic algorithm, which would allow us to use as first line medical treatment those compounds with the highest potential for achieving the fastest control of GH hypersecretion as well as a positive effect upon tumor shrinkage, therefore accelerating the implementation of precision medicine for acromegaly. Moreover, we suggest the development, validation and clinical use of a pasireotide acute test, able to identify patients responsive to pasireotide LAR as the acute octreotide test is able to do for SRLs.

CD133 Expression in Medullary Thyroid Cancer Cells Identifies Patients with Poor Prognosis.

CONTEXT: The identification of markers able to determine medullary thyroid cancer (MTC) patients at high-risk of disease progression is critical to improve their clinical management and outcome. Previous studies have suggested that expression of the stem cell marker CD133 is associated with MTC aggressiveness. OBJECTIVE: To evaluate CD133 impact on disease progression in MTC and explore the regulatory mechanisms leading to the upregulation of this protein in aggressive tumors. PATIENTS: We compiled a series of 74 MTCs with associated clinical data and characterized them for mutations in RET and RAS proto-oncogenes, presumed to be related with disease clinical behavior. RESULTS: We found that CD133 immunohistochemical expression was associated with adverse clinicopathological features and predicted a reduction in time to disease progression even when only RET-mutated cases were considered in the analysis (log-rank test P < 0.003). Univariate analysis for progression-free survival revealed CD133 expression and presence of tumor emboli in peritumoral blood vessels as the most significant prognostic covariates among others such as age, gender, and prognostic stage. Multivariate analysis identified both variables as independent factors of poor prognosis (hazard ratio = 16.6 and 2; P = 0.001 and 0.010, respectively). Finally, we defined hsa-miR-30a-5p, a miRNA downregulated in aggressive MTCs, as a CD133 expression regulator. Ectopic expression of hsa-miR-30a-5p in MZ-CRC-1 (RETM918T) cells significantly reduced CD133 mRNA expression. CONCLUSIONS: Our results suggest that CD133 expression may be a useful tool to identify MTC patients with poor prognosis, who may benefit from a more extensive primary surgical management and follow-up.

Germline mutations in the new E1' cryptic exon of the VHL gene in patients with tumours of von Hippel-Lindau disease spectrum or with paraganglioma.

BACKGROUNDS: The incidence of germline mutations in the newly discovered cryptic exon (E1') of VHL gene in patients with von Hippel-Lindau (VHL) disease and in patients with paraganglioma or pheochromocytoma (PPGL) is not currently known. METHODS: We studied a large international multicentre cohort of 1167 patients with a previous negative genetic testing. Germline DNA from 75 patients with a single tumour of the VHL spectrum ('Single VHL tumour' cohort), 70 patients with multiple tumours of the VHL spectrum ('Multiple VHL tumours' cohort), 76 patients with a VHL disease as described in the literature ('VHL-like' cohort) and 946 patients with a PPGL were screened for E1' genetic variants. RESULTS: Six different genetic variants in E1' were detected in 12 patients. Two were classified as pathogenic, 3 as variants of unknown significance and 1 as benign. The rs139622356 was found in seven unrelated patients but described in only 16 patients out of the 31 390 of the Genome Aggregation Database (p<0.0001) suggesting that this variant might be either a recurrent mutation or a modifier mutation conferring a risk for the development of tumours and cancers of the VHL spectrum. CONCLUSIONS: VHL E1' cryptic exon mutations contribute to 1.32% (1/76) of 'VHL-like' cohort and to 0.11% (1/946) of PPGL cohort and should be screened in patients with clinical suspicion of VHL, and added to panels for Next Generation Sequencing (NGS) diagnostic testing of hereditary PPGL. Our data highlight the importance of studying variants identified in deep intronic sequences, which would have been missed by examining only coding sequences of genes/exomes. These variants will likely be more frequently detected and studied with the upcoming implementation of whole-genome sequencing into clinical practice.

Integrative multi-omics analysis identifies a prognostic miRNA signature and a targetable miR-21-3p/TSC2/mTOR axis in metastatic pheochromocytoma/paraganglioma.

Rationale: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors that present variable outcomes. To date, no effective therapies or reliable prognostic markers are available for patients who develop metastatic PPGL (mPPGL). Our aim was to discover robust prognostic markers validated through in vitro models, and define specific therapeutic options according to tumor genomic features. Methods: We analyzed three PPGL miRNome datasets (n=443), validated candidate markers and assessed them in serum samples (n=36) to find a metastatic miRNA signature. An integrative study of miRNome, transcriptome and proteome was performed to find miRNA targets, which were further characterized in vitro. Results: A signature of six miRNAs (miR-21-3p, miR-183-5p, miR-182-5p, miR-96-5p, miR-551b-3p, and miR-202-5p) was associated with metastatic risk and time to progression. A higher expression of five of these miRNAs was also detected in PPGL patients' liquid biopsies compared with controls. The combined expression of miR-21-3p/miR-183-5p showed the best power to predict metastasis (AUC=0.804, P=4.67·10-18), and was found associated in vitro with pro-metastatic features, such as neuroendocrine-mesenchymal transition phenotype, and increased cell migration rate. A pan-cancer multi-omic integrative study correlated miR-21-3p levels with TSC2 expression, mTOR pathway activation, and a predictive signature for mTOR inhibitor-sensitivity in PPGLs and other cancers. Likewise, we demonstrated in vitro a TSC2 repression and an enhanced rapamycin sensitivity upon miR-21-3p expression. Conclusions: Our findings support the assessment of miR-21-3p/miR-183-5p, in tumors and liquid biopsies, as biomarkers for risk stratification to improve the PPGL patients' management. We propose miR-21-3p to select mPPGL patients who may benefit from mTOR inhibitors.

Recurrent Germline DLST Mutations in Individuals with Multiple Pheochromocytomas and Paragangliomas.

Pheochromocytomas and paragangliomas (PPGLs) provide some of the clearest genetic evidence for the critical role of metabolism in the tumorigenesis process. Approximately 40% of PPGLs are caused by driver germline mutations in 16 known susceptibility genes, and approximately half of these genes encode members of the tricarboxylic acid (TCA) cycle. Taking as a starting point the involvement of the TCA cycle in PPGL development, we aimed to identify unreported mutations that occurred in genes involved in this key metabolic pathway and that could explain the phenotypes of additional individuals who lack mutations in known susceptibility genes. To accomplish this, we applied a targeted sequencing of 37 TCA-cycle-related genes to DNA from 104 PPGL-affected individuals with no mutations in the major known predisposing genes. We also performed omics-based analyses, TCA-related metabolite determination, and 13C5-glutamate labeling assays. We identified five germline variants affecting DLST in eight unrelated individuals (∼7%); all except one were diagnosed with multiple PPGLs. A recurrent variant, c.1121G>A (p.Gly374Glu), found in four of the eight individuals triggered accumulation of 2-hydroxyglutarate, both in tumors and in a heterologous cell-based assay designed to functionally evaluate DLST variants. p.Gly374Glu-DLST tumors exhibited loss of heterozygosity, and their methylation and expression profiles are similar to those of EPAS1-mutated PPGLs; this similarity suggests a link between DLST disruption and pseudohypoxia. Moreover, we found positive DLST immunostaining exclusively in tumors carrying TCA-cycle or EPAS1 mutations. In summary, this study reveals DLST as a PPGL-susceptibility gene and further strengthens the relevance of the TCA cycle in PPGL development.

Economics of gastroenteropancreatic neuroendocrine tumors: a systematic review.

BACKGROUND: Despite current interest, enthusiasm and progress in the development of therapies for gastroenteropancreatic (GEP) neuroendocrine tumors (NETs), there are substantial gaps in the published literature regarding cost-of-illness analyses, economic evaluation and budget impact analyses. Compounding the issue is that data on resource utilization and cost-effectiveness of different diagnostic and therapeutic modalities for GEP-NETs are scarce. METHODS: A systematic review on the economic impact of GEP-NETs was carried out using four databases: EMBASE, PubMed, the National Health Service Economic Evaluation Database and Cochrane review. Fully published articles from January 2000 to May 2017, in English and Spanish, were included. All articles that satisfied the inclusion criteria were included in the systematic review; summary descriptive statistics were used to describe the methodological characteristics. RESULTS: The 14 studies selected included cost-of-illness analyses (n = 4), economic evaluations (n = 7) and budget impact analyses (n = 3). Almost all studies were performed in the United States. Healthcare costs for patients with NETs included medication, outpatient visits, hospitalizations, and check-ups/tests. Reducing adverse events is an area where cost savings could be achieved; however, there was not enough evidence on the cost impact of adverse events. CONCLUSION: There is a lack of data related to resource utilization in the field of GEP-NETs. Therefore, cost-effectiveness and budget impact studies of existing and emerging treatments are urgently needed to help the decision-making process for patients with NETs.

Prognostic and predictive biomarkers for somatostatin analogs, peptide receptor radionuclide therapy and serotonin pathway targets in neuroendocrine tumours.

Neuroendocrine tumours (NETs) are a heterogeneous group of neoplasms regarding their molecular biology, clinical behaviour, prognosis and response to therapy. Several attempts to establish robust predictive biomarkers have failed. Neither tissue markers nor blood borne ones have proven to be successful yet. Circulating tumour cells (CTCs) as "liquid biopsies" could provide prognostic information at the time a therapeutic decision needs to be made and could be an attractive tool for tumour monitoring throughout the treatment period. However, "liquid biopsies" are far from becoming the standard biomarker in NETs. Promising results have been presented over the last few years using a novel biomarker candidate, a multianalyte algorithm analysis PCR-based test (NETest). New technologies will open the field to different ways of approaching the biomarker conundrum in NETs. However, the complications derived from being a heterogeneous group of malignancies will remain with us forever. In summary, there is an unmet need to incorporate new biomarker candidates into clinical research trials to obtain a robust prospective validation under the most demanding scenario.

Optimisation of treatment with lenvatinib in radioactive iodine-refractory differentiated thyroid cancer.

Lenvatinib has been approved for the treatment of advanced differentiated thyroid cancer (DTC) refractory to radioactive iodine (RAI) following the results of the SELECT trial which demonstrated a significant increase in progression-free survival and a high response rates. The data reported for lenvatinib in RAI-refractory DTC (RAI-R DTC) are the most significant to date in this patient population, with a RECIST objective response rate above 60% and almost 80% reduction in the risk of disease progression. Because the first indication in oncology for lenvatinib is specifically in RAI-R DTC, a period of familiarisation with its safety and efficacy profile is required. This review includes a series of specific recommendations for optimising the management of RAI-R DTC with lenvatinib, as well as specific guidelines for minimising the incidence and severity of adverse events (AEs), which enable dose intensity to be increased and this way maximise the benefits of the drug in the patient population treated. These recommendations were defined at a meeting of experts of different specialities, reviewing available scientific evidence on the drug, as well as their own direct personal experience in daily clinical practice. For toxicity to be properly managed, a multidisciplinary approach is required in which the different medical services, nursing staff and the patient and their careers are all involved. It is essential to assess the suitability of patients who are candidates for lenvatinib, as well as their clinical and physiological status prior to treatment. They must then be closely monitored to prevent and detect possible AEs. The main objective should be to maintain the dose that obtains the maximum therapeutic effect, discontinuing the treatment only if the toxicity becomes unmanageable or there is no clinical benefit.

Criteria for diagnosis and postoperative control of acromegaly, and screening and management of its comorbidities: Expert consensus. / Criterios para el diagnóstico y el control poscirugía de la acromegalia, y el cribado y el manejo de sus comorbilidades: recomendaciones de expertos.

Acromegaly is a rare disease with many comorbidities that impair quality of life and limit survival. There are discrepancies in various clinical guidelines regarding diagnosis and postoperative control criteria, as well as screening and optimal management of comorbidities. This expert consensus was aimed at establishing specific recommendations for the Spanish healthcare system. The existing recommendations, the scientific evidence on which they are based, and the main controversies are reviewed. Unfortunately, the low prevalence and high clinical variability of acromegaly do not provide strong scientific evidences. To mitigate this disadvantage, a modified Delphi questionnaire, combining the best available scientific evidence with the collective judgment of experts, was used. The questionnaire, generated after a face-to-face debate, was completed by 17 Spanish endocrinologists expert in acromegaly. A high degree of consensus was reached (79.3%), as 65 of the total 82 statements raised were accepted. Some criteria for diagnosis and postoperative control were identified by this procedure. Regarding comorbidities, recommendations have been established or suggested for screening and management of oncological, cardiovascular, respiratory (sleep apnea), metabolic (dyslipidemia and diabetes), musculoskeletal, and hypopituitarism-related disorders. Consensus recommendations may facilitate and homogenize clinical care to patients with acromegaly in the Spanish health system.

Axitinib treatment in advanced RAI-resistant differentiated thyroid cancer (DTC) and refractory medullary thyroid cancer (MTC).

BACKGROUND: Axitinib, an antiangiogenic multikinase inhibitor (MKI), was evaluated in the compassionate use programme (CUP) in Spain (October 2012-November 2014). SUBJECTS AND METHODS: 47 patients with advanced radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC, n = 34) or medullary thyroid cancer (MTC, n = 13) with documented disease progression were treated with axitinib 5 mg b.i.d. The primary efficacy endpoint was objective response rate (ORR) by Response Evaluation Criteria In Solid Tumors (RECIST) v1.1. Progression-free survival (PFS) and adverse events (AEs) were secondary objectives. Regulatory authorities validated the CUP, and all patients signed informed consent form. RESULTS: Axitinib was administered as first-line therapy in 17 patients (36.2%), as second-line in 18 patients (38.3%) and as third/fourth-line in 12 patients (25.5%). With a median follow-up of 11.5 months (0-24.3), ORR was 27.7% (DTC: 29.4% and MTC: 23.1%) and median PFS was 8.1 months (95% CI: 4.1-12.2) (DTC: 7.4 months (95% CI: 3.1-11.8) and MTC: 9.4 months (95% CI: 4.8-13.9)). Better outcomes were reported with first-line axitinib, with an ORR of 53% and a median PFS of 13.6 months compared with 16.7% and 10.6 months as second-line treatment. Twelve (25.5%) patients required dose reduction to 3 mg b.i.d. All-grade AEs included asthenia (53.2%), diarrhoea (36.2%), hypertension (31.9%) and mucositis (29.8%); grade 3/4 AEs included anorexia (6.4%), diarrhoea (4.3%) and cardiac toxicity (4.3%). CONCLUSION: Axitinib had a tolerable safety profile and clinically meaningful activity in refractory and progressive thyroid cancer regardless of histology as first-line therapy. To our knowledge, this is the first time that cross-resistance between MKIs is suggested in thyroid cancer, highlighting the importance of prospective sequential clinical studies.

PheoSeq: A Targeted Next-Generation Sequencing Assay for Pheochromocytoma and Paraganglioma Diagnostics.

Genetic diagnosis is recommended for all pheochromocytoma and paraganglioma (PPGL) cases, as driver mutations are identified in approximately 80% of the cases. As the list of related genes expands, genetic diagnosis becomes more time-consuming, and targeted next-generation sequencing (NGS) has emerged as a cost-effective tool. This study aimed to optimize targeted NGS in PPGL genetic diagnostics. A workflow based on two customized targeted NGS assays was validated to study the 18 main PPGL genes in germline and frozen tumor DNA, with one of them specifically directed toward formalin-fixed paraffin-embedded tissue. The series involved 453 unrelated PPGL patients, of whom 30 had known mutations and were used as controls. Partial screening using Sanger had been performed in 275 patients. NGS results were complemented with the study of gross deletions. NGS assay showed a sensitivity ≥99.4%, regardless of DNA source. We identified 45 variants of unknown significance and 89 pathogenic mutations, the latter being germline in 29 (7.2%) and somatic in 58 (31.7%) of the 183 tumors studied. In 37 patients previously studied by Sanger sequencing, the causal mutation could be identified. We demonstrated that both assays are an efficient and accurate alternative to conventional sequencing. Their application facilitates the study of minor PPGL genes, and enables genetic diagnoses in patients with incongruent or missing clinical data, who would otherwise be missed.

Capecitabine and temozolomide in grade 1/2 neuroendocrine tumors: a Spanish multicenter experience.

BACKGROUND & METHODS: Capecitabine and temozolomide chemotherapy was used in 65 patients with grade 1/2 neuroendocrine tumors (NETs). 46 patients (70.8%) had pancreatic NETs (pNETs). RESULTS: Response rate was 47.7%, with two complete responses (3.1%), 29 partial responses (44.6%) and 27 patients (41.5%) achieved stable disease. Median progression-free survival was 16.1 months (95% CI: 10.7-21.6) and overall survival was 38.3 months (95% CI: 24.6-51.9). Differences in progression-free survival and overall survival between pNETs and non-pNETs were not found. Nine (13.8%) patients experienced grade 3/4 toxicities, mainly thrombocytopenia (10.8%) and neutropenia (7.7%). CONCLUSION: This is the largest reported series of NETs treated with capecitabine and temozolomide in daily practice and shows that this combination is a promising treatment option for both grade 1/2 pNETs and non-pNETs.

Temozolomide for aggressive ACTH pituitary tumors: failure of a second course of treatment.

INTRODUCTION: Temozolomide (TMZ) is an oral alkylating agent that has been used over the past 8 years to treat aggressive pituitary tumors resistant to conventional therapy. To date, only 25 patients treated with TMZ for ACTH producing pituitary tumors (14 adenomas and 11 carcinomas) have been reported. MATERIALS AND METHODS: We present a retrospective review of the medical records of three patients with aggressive ACTH producing adenomas treated with TMZ. In the three cases there was evidence of progression to conventional therapy before starting TMZ. We used the conventional scheme for the treatment of gliomas until completing 7, 12 and 6 cycles respectively. Reduction in tumor size was evident after the 3rd, 5th and 4th cycle of TMZ and progression free survival was 25, 19 and more than 12 months in the three patients respectively. Improvement of the ocular and visual symptoms was evident after the 4th cycle of treatment in all cases. Normalization of urinary free cortisol levels was achieved after the 3rd and 9th cycle in the two cases with hypercortisolism. Two of the three patients received a second course of treatment when the disease progressed but it did not stop tumor progression. The principal side effects were G3 neutropenia, G1 and G2 thrombocytopenia, G1 lymphopenia, asthenia and nausea. CONCLUSION: The treatment with TMZ is effective and safe in patients with aggressive corticotrophin tumors resistant to conventional therapy. Nevertheless once the disease progresses, a second course of treatment does not seem to be effective.

Long-term treatment with pegvisomant for acromegaly: a 10-year experience.

BACKGROUND: Efficacy of the GH-receptor antagonist pegvisomant (PEG) has differed between preclinical and observational studies mainly due to dose adjustment and IGF-I normalization criteria. An escape phenomenon has also been described, but its definition and underlying causes have not been fully established. OBJECTIVE: To re-evaluate the outcomes of long-term PEG in a series of previously published patients and analyse the escape phenomenon. METHODS: We reviewed all patients with acromegaly resistant to SSA in whom PEG was started as monotherapy, who had been included in a previous publication. We prospectively evaluated 64 (56·3% women) from six tertiary care referral hospitals in Spain, for whom data as of June 2014 were available. Escape to PEG was defined as confirmed loss of biochemical control (IGF-I >1·2xULN), after at least 6 months of previous control with a stable dose of PEG. RESULTS: Patients were followed up for 13·0 (5·9-34·8) years since diagnosis, and 9·0 (4·1-10·4) years since the first administration of PEG. Fifty-one (89·5%) patients had an adequate IGF-I control at the last follow-up visit, 9 of them without treatment. Tumour growth was reported in 6 of 64 cases (9·4%), none of whom had received prior radiotherapy (P = 0·011). Seven patients died during follow-up. We found 16 escapes in 10 patients (15·6%). We identified potential underlying causes in 9 cases (tumour regrowth, previous treatment modifications, concomitant menopause and change in testosterone administration). The reason was unknown in 7 escapes, which occurred in 6 patients (9·4%). All patients, except one, achieved subsequent biochemical control after treatment adjustment. CONCLUSIONS: We reassure the efficacy and safety of long-term PEG. An escape phenomenon may occur, but it can be overcome by adjusting therapy.

Imaging approaches to assess the therapeutic response of gastroenteropancreatic neuroendocrine tumors (GEP-NETs): current perspectives and future trends of an exciting field in development.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a family of neoplasms with a complex spectrum of clinical behavior. Although generally more indolent than carcinomas, once they progress beyond surgical resectability, they are essentially incurable. Systemic treatment options have substantially expanded in recent years for the management of advanced disease. Imaging plays a major role in new drug development, as it is the main tool used to objectively evaluate response to novel agents. However, current standard response criteria have proven suboptimal for the assessment of the antiproliferative effect of many targeted agents, particularly in the context of slow-growing tumors such as well-differentiated NETs. The aims of this article are to discuss the advantages and limitations of conventional radiological techniques and standard response assessment criteria and to review novel imaging modalities in development as well as alternative cancer- and therapy-specific criteria to assess drug efficacy in the field of GEP-NETs.

Recommendations for somatic and germline genetic testing of single pheochromocytoma and paraganglioma based on findings from a series of 329 patients.

BACKGROUND: Nowadays, 65-80% of pheochromocytoma and paraganglioma (PPGL) cases are explained by germline or somatic mutations in one of 22 genes. Several genetic testing algorithms have been proposed, but they usually exclude sporadic-PPGLs (S-PPGLs) and none include somatic testing. We aimed to genetically characterise S-PPGL cases and propose an evidence-based algorithm for genetic testing, prioritising DNA source. METHODS: The study included 329 probands fitting three criteria: single PPGL, no syndromic and no PPGL family history. Germline DNA was tested for point mutations in RET and for both point mutation and gross deletions in VHL, the SDH genes, TMEM127, MAX and FH. 99 tumours from patients negative for germline screening were available and tested for RET, VHL, HRAS, EPAS1, MAX and SDHB. RESULTS: Germline mutations were found in 46 (14.0%) patients, being more prevalent in paragangliomas (PGLs) (28.7%) than in pheochromocytomas (PCCs) (4.5%) (p=6.62×10(-10)). Somatic mutations were found in 43% of those tested, being more prevalent in PCCs (48.5%) than in PGLs (32.3%) (p=0.13). A quarter of S-PPGLs had a somatic mutation, regardless of age at presentation. Head and neck PGLs (HN-PGLs) and thoracic-PGLs (T-PGLs) more commonly had germline mutations (p=2.0×10(-4) and p=0.027, respectively). Five of the 29 metastatic cases harboured a somatic mutation, one in HRAS. CONCLUSIONS: We recommend prioritising testing for germline mutations in patients with HN-PGLs and T-PGLs, and for somatic mutations in those with PCC. Biochemical secretion and SDHB-immunohistochemistry should guide genetic screening in abdominal-PGLs. Paediatric and metastatic cases should not be excluded from somatic screening.