Gender-related differences in patients with carcinoid syndrome: new insights from an Italian multicenter cohort study.

BACKGROUND: The incidence of neuroendocrine neoplasm (NEN) and related carcinoid syndrome (CaS) has increased markedly in recent decades, and women appear to be more at risk than men. As per other tumors, gender may be relevant in influencing the clinical and prognostic characteristics of NEN-associated CS. However, specific data on carcinoid syndrome (CaS) are still lacking. PURPOSE: To evaluate gender differences in clinical presentation and outcome of CaS. METHODS: Retrospective analysis of 144 CaS patients from 20 Italian high-volume centers was conducted. Clinical presentation, tumor characteristics, therapies, and outcomes (progression-free survival, PFS, overall survival, OS) were correlated to gender. RESULTS: Ninety (62.5%) CaS patients were male. There was no gender difference in the site of primary tumor, tumor grade and clinical stage, as well as in treatments. Men were more frequently smokers (37.2%) and alcohol drinkers (17.8%) than women (9.5%, p = 0.002, and 3.7%, p = 0.004, respectively). Concerning clinical presentation, women showed higher median number of symptoms (p = 0.0007), more frequent abdominal pain, tachycardia, and psychiatric disorders than men (53.3% vs 70.4%, p = 0.044; 6.7% vs 31.5%, p = 0.001; 50.9% vs. 26.7%, p = 0.003, respectively). Lymph node metastases at diagnosis were more frequent in men than in women (80% vs 64.8%; p = 0.04), but no differences in terms of PFS (p = 0.51) and OS (p = 0.64) were found between gender. CONCLUSIONS: In this Italian cohort, CaS was slightly more frequent in males than females. Gender-related differences emerged in the clinical presentation of CaS, as well as gender-specific risk factors for CaS development. A gender-driven clinical management of these patients should be advisable.

Pancreatic neuroendocrine tumor progression and resistance to everolimus: the crucial role of NF-kB and STAT3 interplay.

PURPOSE: The finding of mTOR overactivation in patients affected by pancreatic neuroendocrine tumors (Pa-NETs) led to their treatment with the mTOR inhibitor everolimus. Unfortunately, the efficacy of everolimus is restricted by the occurrence of resistance. The mechanisms leading to Pa-NETs' progression and resistance are not well understood. Notably, chronic inflammation is implicated in NET development. NF-kB is involved in inflammation and drug resistance mechanisms through the activation of several mediators, including STAT3. In this respect, NF-κB and STAT3 interaction is implicated in the crosstalk between inflammatory and tumor cells. METHODS: We investigated the expression of NF-kB in different Pa-NETs by RT-qPCR and immunohistochemistry. Then, we studied the role of NF-κB and STAT3 interplay in QGP-1 cells. Subsequently, we assessed the impact of NF-κB and STAT3 inhibitors in QGP-1 cell proliferation and spheroids growth. Finally, we evaluated the implication of the NF-kB pathway in everolimus-resistant Pa-NET cells. RESULTS: We found that the increased NF-kB expression correlates  with a higher grade in Pa-NETs. The activation of the STAT3 pathway induced by TNFα is mediated by NF-kB p65. NF-kB p65 and STAT3 inhibitors decrease QGP-1 viability, spheroids growth, and Pa-NETs cell proliferation. These effects are maintained in everolimus-resistant QGP-1R cells. Interestingly, we found that NF-kB, STAT3, IL-8, and SOCS3 are overexpressed in QGP-1R compared to QGP-1. CONCLUSION: Since the NF-kB pathway is implicated in Pa-NETs' progression and resistance to everolimus, these data could explain the potential use of NF-kB as a novel therapeutic target in Pa-NET patients.

Gastroenteropancreatic grade 3 neuroendocrine tumors: a single entity or a heterogeneous group? A retrospective analysis.

PURPOSE: Grade 3 neuroendocrine tumor (NET G3) is a novel pathologic category within gastro-entero-pancreatic (GEP) neuroendocrine neoplasms (NENs) but its clinical behavior and therapeutic management still remain challenging. Prognostic and predictive factors aiding NET G3 management are needed. PATIENTS AND METHODS: We performed a retrospective analysis from 2015 to 2020 of all patients with > 20% Ki-67, well-differentiated NETs evaluated within our NEN-dedicated multidisciplinary team. We divided the sample according the timing of NET G3 diagnosis, the radiotracers distribution and Ki-67. We analyzed the correlation between these NET G3 features and clinical outcomes. RESULTS: Among 3238 multidisciplinary discussion reports, we selected 55 patients, 48 from GEP and 7 from an occult GEP origin. In 45 patients, NET G3 diagnosis occurred at the beginning of clinical history (upfront-NET G3), whereas in 10, during the NET G1-G2 clinical history (late-NET G3). Patients with ≤ 30% (34/55) vs. > 30% Ki-67 (21/55) had a better overall survival (OS) (p = 0.042); patients with a homogeneous vs. inhomogeneous/negative 68Gallium(68Ga)-DOTA-Peptide Positron Emission Tomography (PET)/computed tomography (CT) showed a trend to a better OS, and a significant better progression-free survival (PFS) (p = 0.033). A better OS was observed for negative/inhomogeneous vs. homogeneous 18-fluorodeoxyglucose (18FDG)-PET/CT (p = 0.027). A trend to a better OS was reported in late- vs. upfront-NET G3, while the latter showed a significantly better response rate (RR) (p = 0.048). CONCLUSION: Our findings suggested that Ki-67 cutoff, functional imaging and the timing to NET G3 diagnosis may help clinicians in more accurate selection of NET G3 management. Prospective studies are needed.

Ten years-experience of sunitinib in the treatment of advanced pan-NETs: an update on safety profile.

INTRODUCTION: Sunitinib still represents a milestone in the treatment for progressive, well-differentiated, advanced panNETs. AREAS COVERED: We performed an evidence reappraisal to critically discuss its safety profile. We included nine studies, five clinical trials and four real-world (RW) studies. Within non-real-world (NRW) studies, diarrhea was the most frequent clinical AE. With regard to G3-4 AEs, fatigue and hypertension were the two most frequent, while neutropenia was the most recurrent hematological one. Considering four real-world trials, hand-foot-syndrome (HFS) was the most frequent clinical any-grade AE of any grade and neutropenia was the most common G3-4. Alongside to the AEs rate, the discontinuation rate of sunitinib due to TRAEs was variable among all the nine selected studies, ranging from 10% to 35% in the NRW setting and from 7% to 31% in the RW setting. Conversely, temporary interruption is an accepted strategy to reduce toxicity, even though not specifically tested in pan-NET. EXPERT OPINION: Till now, sunitinib continues to be one of the main therapeutic options for patients with well differentiated advanced panNETs, potentially covering any line of treatment. Therefore, tolerability plays a crucial role to increase adherence to therapy and maximize QoL.

Should temozolomide be used on the basis of O6-methylguanine DNA methyltransferase status in patients with advanced neuroendocrine tumors? A systematic review and meta-analysis.

BACKGROUND: Temozolomide (TEM) is an active treatment in metastatic neuroendocrine tumors (NETs). Patients affected by glioblastoma multiforme or advanced melanoma treated with TEM who have deficiency of O6-methylguanine DNA methyltransferase (MGMT) have a better responses and survival. However, the predictive role of MGMT in patients with NETs treated with TEM is still debated. METHODS: We conducted a systematic review of the literature and meta-analysis, based on PRISMA methodology, searching in the main databases (PubMed, Embase, Scopus, Web of Science, Cochrane Library and clinical trial.gov) and the proceedings of the main international congresses, until April 26, 2021. RESULTS: Twelve out of 616 articles were selected for our analysis, regarding a total of 858 NET patients treated with TEM-based chemotherapy. The status of MGMT had been tested in 513 (60%) patients, using various methods. The pooled overall response rate (ORR) was higher in MGMT-deficient compared with MGMT-proficient NETs, with a risk difference of 0.31 (95% confidence interval, CI: 0.13-0.50; p < 0.001; I2: 73%) and risk ratio of 2.29 (95% CI: 1.34-3.91; p < 0.001; I2: 55%). The pooled progression free survival (PFS) (hazard ratio, HR = 0.56; 95% CI: 0.43-0.74; p < 0.001) and overall survival (OS) (HR = 0.41; 95% CI: 0.20-0.62; p = 0.011) were longer in MGMT-deficient versus MGMT-proficient NETs. CONCLUSIONS: Our meta-analysis suggested that MGMT status may be predictive of TEM efficacy. However, due to the high heterogeneity of the evaluated studies the risk of biases should be considered. On this hypothesis future homogeneous prospective studies are warranted.

SARS-CoV-2-related pneumonia can be successfully managed in patients with metastatic neuroendocrine tumors: a critical point of view.

Primary neuroendocrine tumors of the thymus are extremely rare. In patients with advanced disease, tumor growth control, and sometimes also syndrome control are the main goals of systemic therapy. Unfortunately, no standard therapies are available in clinical practice; therefore, clinical studies are strongly recommended. Axitinib (AXI) is a tyrosine kinase inhibitor, currently under investigation in an international phase II/III trial including thymic neuroendocrine tumors. Over the past 5 months, the entire world has been facing a devastating medical emergency brought about by a pandemic due to a novel coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in Wuhan, China, in late 2019. Since then, health professionals have been expending all their efforts on trying to provide the best available treatments for patients involved. Patients with cancer, especially those with thoracic involvement, are at higher risk of coronavirus disease 19 (COVID-19) and its complications because of their immunosuppressive status caused by the cancer and the anticancer therapies. As it remains unclear how to optimally manage such patients, we wished to report our experience with a patient with a metastatic neuroendocrine tumor of the thymus infected with SARS-CoV-2 in the hope that it may provide some insights and reflections on the management of cancer patients during this challenging time in our history.