Citations

Abstract Importance Mitotane (Lysodren, o,p'-DDD [1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2-dichloroethane)] is currently the only United States Food and Drug Administration and European Medicines Agency-approved product for the treatment of adrenocortical carcinoma. Observations Mitotane is challenging to administer; however, its toxicities (specifically adrenal insufficiency) are well known, and the management of adverse consequences has established approaches. While often viewed through the prism of a cytotoxic agent, it can also interfere with hormone production making it a valuable asset in managing functional ACC. A recently completed prospective trial has shed some light on its use in the adjuvant setting, but further clarity is needed. Many think mitotane has a role in the advanced or metastatic setting, although prospective data are lacking and retrospective analyses are often difficult to interpret. Conclusions and relevance When used carefully and thoughtfully, especially in patients with hormonal excess, mitotane is an important component of the treatment armamentarium for ACC.

We assessed the efficacy and safety of combining bevacizumab with temsirolimus in patients with advanced extra-pancreatic neuroendocrine tumors. This NCI-sponsored multicenter, open-label, phase II study (NCT01010126) enrolled patients with advanced, recurrent, or metastatic extra-pancreatic neuroendocrine tumors. All patients were treated with temsirolimus and bevacizumab until disease progression or unacceptable toxicity. Temsirolimus 25 mg was administered i.v. on days 1, 8, 15, and 22 and bevacizumab 10 mg/kg i.v. on days 1 and 15 of a 4-week cycle. Discontinuation of temsirolimus or bevacizumab did not require discontinuation of the other agent. The primary endpoints were objective response rate and 6-month progression-free survival rate. Fifty-nine patients were enrolled in this study, and 54 were evaluated for efficacy and adverse events. While median progression-free survival was 7.1 months, the median duration of treatment with temsirolimus was 3.9 months and that with bevacizumab was 3.5 months. The objective response rate of combination therapy was 2%, and 6-month progression-free survival was 48%. The most frequently reported grade 3–4 adverse events included fatigue (13%), hypertension (13%), and bleeding (13%). Close to 54% of the patients discontinued treatment due to adverse events, refusal of further treatment, or treatment delays. Three deaths occurred in the study, of which two were due to treatment-related bowel perforations. Given the minimal efficacy and increased toxicity seen with the combination of bevacizumab and temsirolimus, we do not recommend the use of this regimen in patients with advanced extra-pancreatic neuroendocrine tumors.

TPS660 Background: Deeper comprehension of gastroenteropancreatic neuroendocrine tumor (GEP-NET) characteristics has led to development of therapeutic interventions such as targeted radionuclide therapies (TRT). In the prospective, randomized, controlled, open-label, multi-center, Phase III COMPOSE trial, the radiolabeled somatostatin analogue 177Lu-edotreotide will be compared to approved standard of care with everolimus, CAPTEM or FOLFOX in patients with well-differentiated aggressive grade 2 and 3 (Ki-67 index 15−55%), somatostatin receptor positive GEP-NETS. While TRT is advantageous, a key unmet need is to identify additional markers intended to guide patient selection for TRT. This is highly relevant as TRT is a therapy of growing interest likely to be broadly available for patients with variable phenotypes. Profiling analysis as part of COMPOSE plans to analyze the genetic signature of GEP-NETS through full exome sequencing and gene expression analysis of tumor histology and longitudinal blood samples. This analysis may guide detection of pathogenic mutations in NET patients, to potentially inform treatment and surveillance strategies. Methods: Whole exome analysis of tumor-suppressor- and proto-oncogenes included in several pan-cancer panels, upstream and downstream regulators, and novel candidate genes, will be studied. Following patient consent, historical tumor biopsy and blood samples will undergo genetic analysis. Genetic profiling analysis inclusion will not impact trial involvement or disease management. DNA will be assessed to determine the impact of different types of mutations; mRNA will be assessed to confirm and quantify these assumptions and compare gene expression at different treatment phases. Samples will be analyzed in a central pathology laboratory. The aim of this analysis is to develop software that would integrate genetic data with structural and functional imaging, histopathology and phenotype information for implementation into clinical practice. Clinical trial information: NCT04919226 .

TPS514 Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs), which represent approximately 70% of NETs, frequently develop metastatic disease with limited treatment options. Current standard therapies for well-differentiated high grade 2 and grade 3 GEP-NETs include cytoreductive procedures, somatostatin analogues, molecular targeted therapies (everolimus or sunitinib), chemotherapy and peptide receptor radionuclide therapy (PRRT), with no specified sequence of use. PRRT may stabilize disease and induce objective tumor responses. This treatment uses radiolabeled somatostatin analogues to selectively target somatostatin receptor expressing (SSTR+) tumor cells. 177 Lu-edotreotide is an innovative radiolabeled somatostatin analogue with a favorable safety profile and promising efficacy. Retrospective data in metastatic GEP-NETs treated with two or more 177 Lu-edotreotide cycles demonstrated a progression free survival (PFS) of at least 30 months. The currently recruiting Phase III COMPETE trial compares the efficacy and safety of 177 Lu-edotreotide, versus everolimus, in grade 1 and grade 2 GEP-NETs. Methods: COMPOSE (NCT04919226) is a prospective, randomized, controlled, open-label, multi-center Phase III study, in patients with well-differentiated high grade 2 and grade 3 (Ki-67 index 15−55%), SSTR+, GEP-NETs. This trial is to evaluate the efficacy, safety and patient-reported outcomes of first- or second-line treatment with 177 Lu-edotreotide PRRT compared to best standard of care. It aims to randomize 202 patients 1:1 to a defined number of cycles of 177 Lu-edotreotide or an active comparator (either chemotherapy [CAPTEM or FOLFOX] or everolimus, according to investigator´s choice). The primary endpoint is PFS, assessed every 12 weeks until disease progression (RECIST v1.1), or death, whichever occurs earlier. Secondary outcomes include overall survival, assessed up to 2 years after disease progression. Study recruitment for COMPOSE commenced in September 2021. It is expected that COMPOSE will inform optimal treatment options for patients with well-differentiated high grade 2 and grade 3 SSTR+ GEP-NETs, including for first-line therapy. Clinical trial information: NCT04919226.

Abstract Background Grade 3 gastroenteropancreatic neuroendocrine neoplasms (G3 GEPNENs) are often aggressive, and the optimal treatment is unclear for this subgroup of neuroendocrine neoplasms (NENs). Temozolomide (TEM)-based regimens have been increasingly used to treat grade 1–2 NENs, but their efficacy in G3 NENs remains undetermined. We aimed to assess the clinical efficacy of TEM-containing regimens in advanced grade 3 GEPNENs. Materials and Methods A multicenter retrospective review (2008–2018) of patients with metastatic/unresectable G3 GEPNENs who received a TEM-containing regimen was undertaken within a North American partnership to pool data. The primary endpoint was time to treatment failure (TTF). Radiologic response was extracted from local reports. Results One hundred and thirty patients in six high-volume NEN centers were included (median age 55, 64% male, 18% functional, 67% pancreatic NEN). Forty-nine percent were well-differentiated, 35% poorly differentiated, and 15% unknown based on local pathology reports. The regimen used was capecitabine and temozolomide (CAPTEM) in 92% and TEM alone in 8%. Radiological response by local assessment was seen in 36% of patients. Median TTF was 3.6 months and median overall survival (OS) 19.2 months. Six percent of patients required discontinuation of therapy due to adverse events. TTF was longer in first-line treatment (7.8 months vs. 2.9 months; hazard ratio, 1.62; 95% confidence interval, 1.11–2.36; p = .015) and in patients with pancreatic NENs (panNENs) compared with gastrointestinal NENs (5.8 months vs 1.8 months; p = .04). The overall response rate was higher in the first-line setting (51% vs 29%; p = .02) and in panNEN (41% vs 23%; p = .04). Conclusion This is the largest TEM treatment series in G3 NEN, involving collaboration of several major North American NEN centers as a partnership. Thirty-six percent of patients showed some degree of radiographic response, and treatment was generally well tolerated, although the median duration of response was short. Response rates and time to treatment failure were superior in the first-line setting. CAPTEM should be considered a viable treatment option in this setting. Further randomized trials are warranted. Implications for Practice Neuroendocrine neoplasms (NENs) are heterogeneous, and optimal treatment for aggressive grade 3 (G3) NENs remains undetermined. The capecitabine and temozolomide (CAPTEM) regimen has been used in low-grade pancreas NENs but there are few data for its safety and efficacy in the G3 setting. This article reports on the efficacy of temozolomide-containing regimens, particularly CAPTEM, in management of G3 NENs. The good tolerance and response rate show that CAPTEM should be considered a viable regimen in treatment of G3 NENs pending confirmatory prospective studies.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Neuroendocrine and Adrenal Gland Tumors focus on the diagnosis, treatment, and management of patients with neuroendocrine tumors (NETs), adrenal tumors, pheochromocytomas, paragangliomas, and multiple endocrine neoplasia. NETs are generally subclassified by site of origin, stage, and histologic characteristics. Appropriate diagnosis and treatment of NETs often involves collaboration between specialists in multiple disciplines, using specific biochemical, radiologic, and surgical methods. Specialists include pathologists, endocrinologists, radiologists (including nuclear medicine specialists), and medical, radiation, and surgical oncologists. These guidelines discuss the diagnosis and management of both sporadic and hereditary neuroendocrine and adrenal tumors and are intended to assist with clinical decision-making. This article is focused on the 2021 NCCN Guidelines principles of genetic risk assessment and counseling and recommendations for well-differentiated grade 3 NETs, poorly differentiated neuroendocrine carcinomas, adrenal tumors, pheochromocytomas, and paragangliomas.

Abstract Patients with neuroendocrine tumors (NETs) and carcinoid syndrome experience diarrhea that can have a debilitating effect on quality of life. Diarrhea also may develop in response to other hormonal syndromes associated with NETs, surgical complications, medical comorbidities, medications, or food sensitivities. Limited guidance on the practical approach to the differential diagnosis of diarrhea in these patients can lead to delays in appropriate treatment. This clinical review and commentary underscore the complexity in identifying the etiology of diarrhea in patients with NETs. Based on our collective experience and expertise, we offer a practical algorithm to guide medical oncologists and other care providers to expedite effective management of diarrhea and related symptoms in patients with NETs.

AbstractThis article is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The guidelines panel consisted of medical oncologists, pathologists, gastroenterologists, endocrinologists, and radiologists. The panel reviewed a series of questions regarding the medical management of patients with pancreatic neuroendocrine tumors as well as questions regarding surveillance after resection. The available literature was reviewed for each of the question and panel members voted on controversial topics, and the recommendations were included in a document circulated to all panel members for a final approval.

4032 Background: PNET has long had few effective therapies other than chemotherapy. Placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co primary endpoints were RR and 6-month PFS. Planned enrollment was 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: 55 pts were eligible for response assessment. Confirmed PR was documented in 20 of 55 patients (37%). 44 of 55 (80%) patients were progression-free at 6 months. Of 49 pts evaluable for this endpoint, 12 month PFS is 49%. 15 patients remain on therapy. For evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (18%), hyperglycemia (13%), fatigue (11%). leukopenia (9%), headache (9%), proteinuria (7%), and hypokalemia (7%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 37%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 80% in a population of patients with RECIST criteria progression within 7 months of study entry. Phase III trials of combined VEGF/mTOR inhibition in PNET should be pursued. Clinical trial information: NCT01010126.

4047 Background: PNET has long had few effective therapies other than chemotherapy. Recent placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/ PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co-primary endpoints were RR and 6-month PFS. Planned enrollment is 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: Confirmed PR was documented in 13 of the first 25 (52%) evaluable patients. 21 of 25 (84%) patients were progression-free at 6 months. Both endpoints exceeded the protocol-defined criteria to continue enrollment. For 36 evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (14%), leukopenia (11%), lymphopenia (11%), hyperglycemia (11%), mucositis (8%), hypokalemia (8%), and fatigue (8%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 52%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 84% in a population of patients with RECIST criteria progression within 7 months of study entry. Accrual is ongoing.