We conducted a retrospective/prospective worldwide study on patients with neuroendocrine neoplasms (NENs) and a molecularly proven SARS-CoV-2 positivity. Preliminary results regarding 85 patients of the INTENSIVE study have been published in 2021. Now we are reporting the 2-year analysis.Here, we are reporting data from consecutive patients enrolled between 1 June 2020, and 31 May 2022. Among the 118 contacted centers, 25 were active to enroll and 19 actively recruiting at the time of data cut-off for a total of 280 patients enrolled. SARS-CoV-2 positivity occurred in 47.5% of patients in 2020, 35.1% in 2021, and 17.4% in 2022. The median age for COVID-19 diagnosis was 60 years. Well-differentiated tumors, non-functioning, metastatic stage, and gastroenteropancreatic (GEP) primary sites represented most of the NENs. COVID-19-related pneumonia occurred in 22.8% of the total, with 61.3% of them requiring hospitalization; 11 patients (3.9%) needed sub-intensive or intensive care unit therapies and 14 patients died (5%), in 11 cases (3.9%) directly related to COVID-19. Diabetes mellitus and age at COVID-19 diagnosis > 70 years were significantly associated with COVID-19 mortality, whereas thoracic primary site with COVID-19 morbidity. A significant decrease in both hospitalization and pneumonia occurred in 2022 vs 2020. In our largest series of NEN patients with COVID-19, the NEN population is similar to the general population of patients with NEN regardless of COVID-19. However, older age, non-GEP primary sites and diabetes mellitus should be carefully considered for increased COVID-19 morbidity and mortality. Relevant information could be derived by integrating our results with NENs patients included in other cancer patients with COVID-19 registries.

No validated prognostic tool is available for predicting overall survival (OS) of patients with well-differentiated neuroendocrine tumors (WDNETs). This study, conducted in three independent cohorts of patients from five different European countries, aimed to develop and validate a classification prognostic score for OS in patients with stage IV WDNETs. We retrospectively collected data on 1387 patients: (i) patients treated at the Istituto Nazionale Tumori (Milan, Italy; n = 515); (ii) European cohort of rare NET patients included in the European RARECAREnet database (n = 457); (iii) Italian multicentric cohort of pancreatic NET (pNETs) patients treated at 24 Italian institutions (n = 415). The score was developed using data from patients included in cohort (i) (training set); external validation was performed by applying the score to the data of the two independent cohorts (ii) and (iii) evaluating both calibration and discriminative ability (Harrell C statistic). We used data on age, primary tumor site, metastasis (synchronous vs metachronous), Ki-67, functional status and primary surgery to build the score, which was developed for classifying patients into three groups with differential 10-year OS: (I) favorable risk group: 10-year OS ≥70%; (II) intermediate risk group: 30% ≤ 10-year OS < 70%; (III) poor risk group: 10-year OS <30%. The Harrell C statistic was 0.661 in the training set, and 0.626 and 0.601 in the RARECAREnet and Italian multicentric validation sets, respectively. In conclusion, based on the analysis of three ‘field-practice’ cohorts collected in different settings, we defined and validated a prognostic score to classify patients into three groups with different long-term prognoses.