Targeting neuroendocrine tumors with octreotide and lanreotide: Key points for clinical practice from NET specialists

Octreotide and lanreotide are the two somatostatin analogs (SSA) currently available in clinical practice. They have been approved first to control the clinical syndrome (mainly carcinoid syndrome) associated with functioning neuroendocrine tumors (NET) and later for tumor growth control in advanced low/intermediate grade NET. Although evidence regarding their role, especially as antiproliferative therapy, has been increasing over the years some clinical indications remain controversial. Solicited by AIOM (Italian Association of Medical Oncology) a group of clinicians from various specialties, including medical oncology, endocrinology, and gastroenterology, deeply involved in NET for their clinical and research activity, addressed eight open questions, critically reviewing evidence and guidelines and sharing clinical take-home messages. The questions regarded the use of long-acting octreotide and lanreotide in the following settings: functioning and non-functioning NET refractory to label dose, first-line metastatic pulmonary NET, combination with other therapy with an antiproliferative intent, maintenance in NET responding to other therapies, adjuvant treatment, Ki-67-related cut-off, somatostatin receptor imaging, safety, and feasibility. The level of evidence is not absolute for the majority of these clinical contexts, so it is recommended to distinguish routine versus sporadic utilization in very selected cases. Mention of such specific issues by the main European guidelines (ENETS, European Neuroendocrine Tumor Society, and ESMO, European Society for Medical Oncology) was explored and their position reported. However, different clinical decisions on single patients could be made if the case is carefully discussed within a NET-dedicated multidisciplinary team.

Risk of preoperative understaging of duodenal neuroendocrine neoplasms: a plea for caution in the treatment strategy

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.

Impact of the SARS-CoV2 pandemic dissemination on the management of neuroendocrine neoplasia in Italy: a report from the Italian Association for Neuroendocrine Tumors (Itanet)

INTRODUCTION

The organization of the healthcare system has significantly changed after the recent COVID-19 outbreak, with a negative impact on the management of oncological patients. The present survey reports data collected by the Italian Association for Neuroendocrine Tumors on the management of patients with neuroendocrine neoplasia (NEN) during the pandemic dissemination.

METHODS

A survey with 57 questions was sent to NEN-dedicated Italian centers regarding the management of patients in the period March 9, 2020, to May 9, 2020 RESULTS: The main modification in the centers' activity consisted of decreases in newly diagnosed NEN patients (- 76.8%), decreases in performed surgical procedures (- 58%), delays to starting peptide receptor radionuclide therapy (45.5%), postponed/canceled follow-up examinations (26%), and canceled multidisciplinary teams' activity (20.8%). A low proportion of centers (< 10%) reported having to withdraw systemic anti-tumor medical treatment due to concerns about the pandemic situation, whereas PRRT was withdrawn from no patients.

CONCLUSION

Although the COVID-19 outbreak induced the centers to reduce some important activities in the management of NEN patients, the Italian network was able to provide continuity in care without withdrawing anti-tumor treatment for the majority of patients.

[18F]FDG-PET/CT and long-term responses to everolimus in advanced neuroendocrine neoplasia

PURPOSE

This study aims to identify in patients with neuroendocrine neoplasia (NEN) the potential correlation between FDG-PET findings and responses to everolimus therapy to identify predictors of long-term efficacy.

METHODS

Retrospective analysis of patients with sporadic, advanced, progressive NEN treated with everolimus was performed based on the available data on FDG-PET patients obtained before commencing therapy. Data are expressed as the median (25-75th IQR). Risk factor analysis and survival analysis were performed by logistic regression and Cox proportional hazard regression and the determination of Kaplan-Meier curves, as appropriate.

RESULTS

Sixty-six patients were evaluated (NET G1 19.7%, NET G2 75.7%, and NET G3 4.6%), including 45.4% with positive FDG-PET findings. Overall, disease stabilization and a partial response were achieved for 71.2% and 6% of patients, respectively. A long-term response (> 24 months) was observed in 33% of patients. Ki67 was the only predictor of tumor progression (p = 0.03). No significant difference in clinical outcomes was observed between patients with positive or negative FDG-PET findings (median PFS was 24 months and 18 months, respectively, p = 0.337; the disease control rate was 83.3% and 70%, respectively, p = 0.245).

CONCLUSIONS

Everolimus is a valid therapeutic option for advanced, progressive, well-differentiated NEN, even in patients with positive FDG-PET findings.

Sporadic non-functioning pancreatic neuroendocrine tumours: multicentre analysis

BACKGROUND

Outcomes after surgery for sporadic pancreatic neuroendocrine neoplasms (Pan-NENs) were evaluated.

METHODS

This multicentre study included patients who underwent radical pancreatic resection for sporadic non-functioning Pan-NENs. In survival analysis, the risk of mortality in this cohort was analysed in relation to that of the matched healthy Italian population. Relative survival (RS) was calculated as the rate between observed and expected survival. Factors related to RS were investigated using multivariable modelling.

RESULTS

Among 964 patients who had pancreatic resection for sporadic non-functioning Pan-NENs, the overall RS rate was 91.8 (95 per cent c.i. 81.5 to 96.5) per cent. 2019 WHO grade (hazard ratio (HR) 5.75 (s.e. 4.63); P = 0.030) and European Neuroendocrine Tumour Society (ENETS) TNM stage (6.73 (3.61); P < 0.001) were independent predictors of RS. The probability of a normal lifespan for patients with G1, G2, G3 Pan-NENS, and pancreatic neuroendocrine carcinomas (Pan-NECs) was 96.7, 54.8, 0, and 0 per cent respectively. The probability of a normal lifespan was 99.8, 99.3, 79.8, and 46.8 per cent for those with stage I, II, III, and IV disease respectively. The overall disease-free RS rate was 73.6 (65.2 to 79.5) per cent. 2019 WHO grade (HR 2.10 (0.19); P < 0.001) and ENETS TNM stage (HR 2.50 (0.24); P < 0.001) significantly influenced disease-free RS. The probability of disease-free survival was 93.2, 84.9, 45.2, and 6.8 per cent for patients with stage I, II, III, and IV disease, and 91.9, 45.2, 9.4, and 0.7 per cent for those with G1, G2, G3 Pan-NENS, and Pan-NECs, respectively.

CONCLUSION

A surgical approach seems without benefit for Pan-NECs, and unnecessary for small G1 sporadic Pan-NENs. Surgery alone may be insufficient for stage III-IV and G3 Pan-NENs.

Second primary neoplasms in patients with lung and gastroenteropancreatic neuroendocrine neoplasms: Data from a retrospective multi-centric study

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.

Systematic review of resection of primary midgut carcinoid tumour in patients with unresectable liver metastases

BACKGROUND

Surgery for small intestinal neuroendocrine tumours (SI-NETs) is limited by metastatic disease in most patients. However, resection of the primary lesion alone has been advocated in patients with unresectable liver metastases. The present systematic review investigated the value of surgical resection of the primary lesion in patients with unresectable metastatic disease.

METHODS

MEDLINE was searched for studies reporting the outcome of patients with SI-NETs and unresectable liver metastases where there was an explicit comparison between resection of the primary lesion alone and no resection. The primary outcome was overall survival. Secondary outcomes were progression-free survival, treatment-related mortality and relief of symptoms.

RESULTS

Meta-analysis was not possible, but six studies were analysed qualitatively to highlight useful information. Possible confounders in these studies were the inclusion of patients with other primary tumour sites, unknown primary tumour or non-metastatic disease. Bearing in mind these limitations, there was a clear trend towards longer survival in patients who underwent surgical resection in all studies; their median overall survival ranged from 75 to 139 months compared with 50-88 months in patients who did not have resection. The difference between the two groups was statistically significant in three studies. Data on symptomatic improvement were scarce and did not suggest a clear benefit of surgery. Surgery-related mortality seemed low.

CONCLUSION

Available data suggest a possible benefit of resection of the primary lesion in patients with unresectable liver metastases, but the studies have several limitations and the results should therefore be considered with caution.