Eads, Jennifer R.

High-grade neuroendocrine neoplasms are a rare disease entity and account for approximately 10% of all neuroendocrine neoplasms. Because of their rarity, there is an overall lack of prospectively collected data available to advise practitioners as to how best to manage these patients. As a result, best practices are largely based on expert opinion. Recently, a distinction was made between well-differentiated high-grade (G3) neuroendocrine tumors and poorly differentiated neuroendocrine carcinomas, and with this, pathologic details, appropriate imaging practices and treatment have become more complex. In an effort to provide practitioners with the best guidance for the management of patients with high-grade neuroendocrine neoplasms of the gastrointestinal tract, pancreas, and gynecologic system, the North American Neuroendocrine Tumor Society convened a panel of experts to develop a set of recommendations and a treatment algorithm that may be used by practitioners for the care of these patients. Here, we provide consensus recommendations from the panel on pathology, imaging practices, management of localized disease, management of metastatic disease and surveillance and draw key distinctions as to the approach that should be utilized in patients with well-differentiated G3 neuroendocrine tumors vs poorly differentiated neuroendocrine carcinomas.

Colorectal cancer (CRC) is the third most common malignancy worldwide. It is projected to increase by 3.2 million new cases and account for 1.6 million deaths by 2040. Mortality is largely due to limited treatment options for patients who present with advanced disease. Thus, the development of effective and tolerable therapies is crucial. Chemotherapy has been the backbone of systemic treatment of advanced CRC, but utility has been limited because of invariable resistance to therapy, narrow mechanisms of action, and unfavorable toxicity profile. Tumors that are mismatch repair-deficient have demonstrated remarkable response to immune checkpoint inhibitor therapy. However, most CRC tumors are mismatch repair-proficient and represent an unmet medical need. Although ERBB2 amplification occurs only in a few cases, it is associated with left-sided tumors and a higher incidence of brain metastasis. Numerous combinations of HER2 inhibitors have demonstrated efficacy, and antibody-drug conjugates against HER2 represent innovative strategies in this area. The KRAS protein has been classically considered undruggable. Fortunately, new agents targeting KRAS G12C mutation represent a paradigm shift in the management of affected patients and could lead the advancement in drug development for the more common KRAS mutations. Furthermore, aberrant DNA damage response is present in 15%-20% of CRCs, and emerging innovative combinations with poly (ADP-ribose) polymerase (PARP) inhibitors could improve the current therapeutic landscape. Multiple novel biomarker-driven approaches in the management of patients with advanced CRC tumors are reviewed in this article.

4020 Background: High grade (G3) GEPNENs are a rare and heterogeneous disease entity for which there is little prospective treatment data. EP chemotherapy is the treatment standard but this may not be appropriate for all G3 GEPNEN pts. CAPTEM has demonstrated activity in G3 GEPNENs and may be a promising alternative. EA2142 aimed to determine if CAPTEM was superior to EP in pts with G3 GEPNENs. Methods: This was a multicenter, randomized (1:1) phase II trial for pts with a locally advanced and unresectable or metastatic well differentiated G3 neuroendocrine tumor (NET) or a poorly differentiated, non-small cell G3 neuroendocrine carcinoma (NEC) of suspected gastrointestinal origin and an ECOG PS of 0-2. Pathology must have demonstrated a Ki-67 of 20-100% or at least 10 mitoses/10 high powered field. Pts were randomized to receive capecitabine 750 mg/m2 orally every 12 hours on days 1-14 and temozolomide 200 mg/m2 orally once daily on days 10-14 of a 28-day treatment cycle (Arm A) or etoposide 100 mg/m2 daily on days 1-3 with either cisplatin 25 mg/m2 daily on days 1-3 or carboplatin AUC 5 on day 1 of a 21-day treatment cycle (Arm B). Restaging scans were performed every 8 weeks and toxicity monitored per CTCAEv4. Final statistical plan was to accrue 80 pts to detect a 67% improvement in progression free survival (PFS) (primary endpoint) with CAPTEM as compared to EP, 80% power and one-sided significance level of 0.10. A planned interim analysis for efficacy and futility was conducted. Results: A total of 67 pts were enrolled (Arm A, n=32; Arm B, n=35). Male 58%, African American 4%, Asian 3%. Mean age 61. Among 63 eligible pts, primary tumor site pancreatic 56%, non-pancreatic 43%. Poorly differentiated 57%, well differentiated 33%, unknown 10%. Mean Ki-67 48% (Arm A), 60% (Arm B). The study was closed prior to full accrual due to futility at 57.7% information time. In the interim analysis, among 62 eligible pts, PFS, overall survival and response rate with CAPTEM were 2.43 months (mos) (95% CI 2.04, 7.72), 12.6 mos, 9% respectively vs 5.36 mos (95% CI 2.14, 7.23), 13.6 mos and 10% with EP. Toxicity was evaluable in 57 pts with Grade (G) 3/4 events occurring in 29% of pts on Arm A, 66% of pts on Arm B. G3/4 events occurring in more than 5% of pts on Arm A—febrile neutropenia (n=2); abdominal pain (n=2); diarrhea (n=2); nausea (n=2); neutropenia (n=2); dehydration (n=2) and on Arm B—anemia (n=8); febrile neutropenia (n=2); fatigue (n=2); lymphopenia (n=2); neutropenia (n=12); thrombocytopenia (n=4); leukopenia (n=6). There was one G5 event on Arm A due to sepsis. Conclusions: CAPTEM does not appear to be superior to EP chemotherapy as front-line treatment for pts with G3 NENs but does demonstrate a more favorable toxicity profile. Studies assessing G3 NET independently of G3 NEC are needed. Clinical trial information: NCT02595424.

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.