Search

Background: Duodenal gastric metaplasia (DGM) is considered a precancerous lesion. No data are available regarding its possible role as a risk factor for duodenal neuroendocrine neoplasms (dNENs). Aims: To assess the prevalence of DGM in a cohort of dNENs. Methods: Subgroup analysis of a retrospective study including dNEN patients who underwent surgical resection between 2000 and 2019 and were observed at eight Italian tertiary referral centers. Results: 109 dNEN patients were evaluated. Signs of DGM associated with the presence of dNEN were reported in 14 patients (12.8%). Among these patients, nine (64.4%) had a dNEN of the superior part of the duodenum, one (7.1%) a periampullary lesion, three (21.4%) a dNEN located in the second portion of the duodenum, with a different localization distribution compared to patients without DGM (p = 0.0332). Ten were G1, three G2, and in one patient the Ki67 was not available. In the group with DGM, six patients (35.7%) were classified at stage I, five (28.6%) at stage II, three (21.4%) at stage III, and no one at stage IV. In the group without DGM, 20 patients (31%) were at stage I, 15 (15%) at stage II, 42 (44%) at stage III, and 19 (20%) at stage IV (p = 0.0236). At the end of the study, three patients died because of disease progression. Conclusions: our findings might suggest that DGM could represent a feature associated with the occurrence of dNEN, especially for forms of the superior part of the duodenum, which should be kept in mind in the endoscopic follow up of patients with DGM. Interestingly, dNEN inside DGM showed a more favorable staging, with no patients in stage IV. The actual relationship and the clinical relevance of this possible association require further clarification.

Purpose: To explore the role of fully hybrid 68Ga-DOTATOC PET/MR imaging and radiomic parameters in predicting histopathological prognostic factors in patients with pancreatic neuroendocrine tumours (PanNETs) undergoing surgery. Methods: One hundred eighty-seven consecutive 68Ga-DOTATOC PET/MRI scans (March 2018–June 2020) performed for gastroenteropancreatic neuroendocrine tumour were retrospectively evaluated; 16/187 patients met the eligibility criteria (68Ga-DOTATOC PET/MRI for preoperative staging of PanNET and availability of histological data). PET/MR scans were qualitatively and quantitatively interpreted, and the following imaging parameters were derived: PET-derived SUVmax, SUVmean, somatostatin receptor density (SRD), total lesion somatostatin receptor density (TLSRD), and MRI-derived apparent diffusion coefficient (ADC), arterial and late enhancement, necrosis, cystic degeneration, and maximum diameter. Additionally, first-, second-, and higher-order radiomic parameters were extracted from both PET and MRI scans. Correlations with several PanNETs’ histopathological prognostic factors were evaluated using Spearman’s coefficient, while the area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to evaluate parameters’ predictive performance. Results: Primary tumour was detected in all 16 patients (15/16 by 68Ga-DOTATOC PET and 16/16 by MRI). SUVmax and SUVmean resulted good predictors of lymphnodal (LN) involvement (AUC of 0.850 and 0.783, respectively). Second-order radiomic parameters GrayLevelVariance and HighGrayLevelZoneEmphasis extracted from T2 MRI demonstrated significant correlations with LN involvement (adjusted p = 0.009), also showing good predictive performance (AUC = 0.992). Conclusion: This study demonstrates the role of the fully hybrid PET/MRI tool for the synergic function of imaging parameters extracted by the two modalities and highlights the potentiality of imaging and radiomic parameters in assessing h

Purpose: Pretreatment staging is the milestone for planning either surgical or endoscopic treatment in duodenal neuroendocrine neoplasms (dNENs). Herein, a series of surgically treated dNEN patients was evaluated to assess the concordance between the pre- and postsurgical staging. Methods: Retrospective analysis of patients with a histologically confirmed diagnosis of dNENs, who underwent surgical resection observed at eight Italian tertiary referral centers. The presurgical TNM stage, based on the radiological and functional imaging, was compared with the pathological TNM stage, after surgery. Results: From 2000 to 2019, 109 patients were included. Sixty-six patients had G1, 26 a G2, 7 a G3 dNEN (Ki-67 not available in 10 patients). In 46/109 patients (42%) there was disagreement between the pre- and postsurgical staging, being it understaged in 42 patients (38%), overstaged in 4 (3%). As regards understaging, in 25 patients (22.9%), metastatic loco-regional nodes (N) resulted undetected at both radiological and functional imaging. Understaging due to the presence of distal micrometastases (M) was observed in 2 cases (1.8%). Underestimation of tumor extent (T) was observed in 12 patients (11%); in three cases the tumor was understaged both in T and N extent. Conclusions: Conventional imaging has a poor detection rate for loco-regional nodes and micrometastases in the presurgical setting of the dNENs. These results represent important advice when local conservative approaches, such as endoscopy or local surgical excision are considered and it represents a strong recommendation to include endoscopic ultrasound in the preoperative tools for a more accurate local staging.

Background: Patients with sporadic neuroendocrine neoplasms may exhibit a higher risk of a second primary tumor than the general population. Aim: This study aimed to analyze the occurrence of second primary malignancies. Methods: A retrospective cohort of 2757 patients with sporadic lung and gastro-entero-pancreatic neuroendocrine neoplasms, managed at eight Italian tertiary referral Centers, was included. Results: Between 2000 and 2019, a second primary malignancy was observed in 271 (9.8%) neuroendocrine neoplasms patients with 32 developing a third tumor. There were 135 (49.8%) females and the median age was 64 years. The most frequent locations of the second tumors were breast (18.8%), prostate (12.5%), colon (9.6%), blood tumors (8.5%), and lung (7.7%). The second primary tumor was synchronous in 19.2% of cases, metachronous in 43.2%, and previous in 37.6%. As concerned the neuroendocrine neoplasms, the 5- and 10-year survival rates were 87.8% and 74.4%, respectively. PFS for patients with a second primary malignancy was shorter than for patients without a second primary malignancy. Death was mainly related to neuroendocrine neoplasms. Conclusion: In NEN patients the prevalence of second primary malignancies was not negligible, suggesting a possible neoplastic susceptibility. Overall survival was not affected by the occurrence of a second primary malignancy.

Aim To explore the potentiality of radiomics analysis, performed on 68Ga-DOTATOC and fluorine-18-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) images, in predicting tumour aggressiveness and outcome in patients candidate to surgery for pancreatic neuroendocrine neoplasms (PanNENs). Patients and methods Retrospective study including 61 patients who underwent 68Ga-DOTATOC and 18F-FDG PET/CT before surgery for PanNEN. Semiquantitative variables [SUVmax and somatostatin receptor density (SRD) for 68Ga-DOTATOC PET; SUVmax and MTV for 18F-FDG PET] and texture features [intensity variability, size zone variability (SZV), zone percentage, entropy; homogeneity, dissimilarity and coefficient of variation (Co-V)] have been analysed to evaluate their possible role in predicting tumour characteristics. Principal component analysis (PCA) was firstly performed and then multiple regression analyses were performed by using the extracted principal components. Results Regarding 68Ga-DOTATOC PET, SZV, entropy, intensity variability and SRD were predictive for tumour dimension. Regarding 18F-FDG PET, intensity variability, SZV, homogeneity, SUVmax and MTV were predictive for tumour dimension. Four principal components were extracted from PCA: PC1 correlated with all 18F-FDG variables, while PC2, PC3 and PC4 with 68Ga-DOTATOC variables. PC1 was the only significantly predicting angioinvasion (P = 0.0222); PC4 was the only one significantly predicting lymph nodal involvement (P = 0.0151). All principal components except PC4 significantly predicted tumour dimension (P <0.0001 for PC1, P = 0.0016 for PC2 and P < 0.0001 for PC3). Co-V from 68Ga-DOTATOC PET/CT was predictive of the outcome. Conclusion Specific texture features derived from preoperative 68Ga-DOTATOC and 18F-FDG PET/CT could noninvasively predict specific tumour characteristics and patients' outcome, delineating the potential role of dual tracer technique and texture analysis in the risk assessment of patients

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) with favorable pathological and clinical features may be considered as indolent lesions, and therefore be amenable to conservative management. According to the primary tumor site, different non-aggressive approaches, based on endoscopic resection or simple active surveillance, can be proposed to selected patients fulfilling specific criteria. Tumor size, Ki67 proliferative index and depth of invasion are markers that can be used in order to identify these subjects. Patients with type I gastric NENs <1 cm as well as those with non-ampullary duodenal NENs <1 cm with no associated syndrome can be safely managed by endoscopic resection. On the other hand, an active surveillance approach is preferred over surgery for patients with asymptomatic, non-functioning pancreatic NENs ≤2 cm without dilation of the main pancreatic duct or bile duct. As far as NENs of the appendix are concerned, appendectomy should be considered as curative when a R0 resection has been achieved in the presence of a tumor ≤1.5 cm, graded as G1 and without lymphovascular invasion. Finally, G1 rectal NENs ≤1 cm without invasion of the muscular layer can be safely treated by endoscopic resection. Therefore, surgeons should be aware of the existence of indolent GEP-NENs, in order to avoid unnecessary operations with associated postoperative complications.