Full Surgical Resection Should Be Performed Whenever Possible for Gastroenteropancreatic NETs

“Full surgical resection (R0) of gastroenteropancreatic neuroendocrine tumors (NETs) is associated with a greater than 90% survival rate at five years, according to findings presented at the 2015 North American Neuroendocrine Tumor Society (NANETS) symposium. The rate of recurrence varied by tumor location and stage, but the majority of patients with all types of NETs who underwent full resection were still free of recurrence in the five-year time frame.

“ ‘The presence of metastatic disease does not seem as though it should deter attempts at R0 resection when it’s feasible,’ according to lead author Katherine Van Loon, MD, MPH, a gastrointestinal cancer specialist at the University of California, San Francisco, Medical Center. She noted that there were differences in disease-free survival in patients who had NETs in the pancreas and small bowel depending on their stage at diagnosis, but a significant difference in overall survival was not detected.

“Current NCCN guidelines recommend that patients with gastrointestinal NETs undergo complete resection of the primary tumor and metastases whenever possible, but until now, large multicenter studies looking at recurrence rates in patients who undergo this procedure have not be conducted.”


Biomarker Needed for CAPTEM Regimen in Metastatic Pancreatic NETs

“Treatment with capecitabine and temozolomide (CAPTEM) is an effective therapy for patients with metastatic pancreatic neuroendocrine tumors (pNETs), but the efficacy of several predictive markers previously thought to determine which patients might respond to the regimen could not be validated, according to a presentation at the 2015 NANETS Symposium.

“ ‘In our study we tried to assess the role of potential predictors of response to temozolomide-based regimens in metastatic pNETs,’ according to lead author Mauro Cives, MD, who presented the findings at the 2015 North American Neuroendocrine Tumor Society symposium. The markers the investigators evaluated were expression of MGMT, proliferative activity, and ALT activation.

“Investigators looked at 143 patients with metastatic pNETs treated at Moffitt who had undergone therapy with CAPTEM and retrospectively evaluated them for radiographic response. ‘This is the largest reported cohort of pNET patients treated with temozolomide-based chemotherapy,’ said Cives, a research associate in the Department of GI Oncology at the Moffitt Cancer Center and Research Institute in Tampa, Florida.”


Video: Dr. Kunz on Potential of Immunotherapy in Neuroendocrine Tumors

“Pamela L. Kunz, MD, assistant professor of Medicine (Oncology), Stanford University School of Medicine, discusses the potential of immunotherapy in the treatment of patients with neuroendocrine tumors (NETs).

“There are currently some clinical trials under development looking at immunotherapy in NETs both at Stanford University School of Medicine and University of Pennsylvania, Kunz explains. One phase I/II trial will examine the safety and efficacy of intratumoral injection of ipilimumab combined with an anti—PD-L1 agent in these patients.”

“It is possible that immunotherapy agents could be agnostic to disease sites, Kunz says. Though it was originally believed that PD-1/PD-L1 expression is a requirement to be a predictive biomarker, additional research could show that it may not be necessary.”

Click through to watch the video.


Lu-Dotatate Shows Unprecedented PFS in Midgut NETs

“The radiopharmaceutical Lu-Dotatate (177Lutetium DOTATATE; Lutathera) demonstrated an unprecedented 79% reduction in the risk of progression or death compared with high-dose octreotide LAR (60 mg) in patients with progressive, metastatic midgut neuroendocrine tumors (NETs), according to results from NETTER-1 trial presented by Jonathan Strosberg, MD, at the 2015 NANETS Symposium.”

” ‘The findings were, in my opinion, extraordinarily impressive, the median progression-free survival improved by nearly 80%, which is fairly unprecedented in oncologic studies,’ said Strosberg, a medical oncologist and researcher at the Moffitt Cancer Center. ‘The finding is important because limited therapeutic options exist for such patients, who comprise 20% to 45% of neuroendocrine tumor cases.’ ”

“The NETTER-1 trial is the first prospective, randomized, phase III study for patients with midgut NETs, specifically those in the ileum and cecum. Patients in the trial had progressed on prior therapy with octreotide at 30 mg and had inoperable, somatostatin receptor positive tumors.”


Gene Mutation Signals Poor Prognosis for Pancreatic Tumors

“For patients with pancreatic neuroendocrine tumors, the presence of recently identified mutations in two key genes is a prognostic factor for poor outcome, researchers report.

” ‘We found loss of nuclear expression in about 23% of the tumors that we studied, and this loss of expression was associated with worse tumors from the outset,’ lead investigator Michelle Heayn, MD, a second-year pathology resident at the University of Pittsburgh Medical Center, told Medscape Medical News.

“Pancreatic tumors with neuroendocrine histology frequently respond to chemotherapy and have a more favorable prognosis than the more common pancreatic adenocarcinomas. However, the mutations are associated with worse disease-free and disease-specific survival.”


Results of International Trial Show Promise in Rare, Difficult to Treat Cancer

“Neuroendocrine tumours (NETs) develop in the neuroendocrine system, responsible for producing the hormones that regulate the working of different organs in the body. They are rare, incurable, and treatments for them are limited, especially once they have become advanced. Now an international team of researchers has shown that the use of the mTOR inhibitor, everolimus, can delay tumour growth among both gastrointestinal and lung NETs. This is particularly important for patients with the lung tumours, the researchers say, because there is currently no approved treatment for such cases.

“Reporting on the results of the RADIANT-4 trial, a placebo-controlled, double-blind, phase III study carried out in centres in 13 European countries, Korea, Japan, Canada, and the US, Professor James Yao, MD, Chair of the Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA, will tell the 2015 European Cancer Congress today (Sunday) that the treatment had a significant effect in non-functional NETs. Non-functional NETs either do not secret a hormone, or secrete one that does not cause symptoms, and are therefore often diagnosed later when the cancer has become advanced. ‘About 80% of all NETs are thought to be non-functional, so, unfortunately, late diagnosis is common and poses a major problem for these patients,’ he will say.”


Pancreatic Neuroendocrine Tumors: A Lesser Threat than Adenocarcinomas, but Still Hard to Treat


Pancreatic neuroendocrine tumors (PNETs) constitute only about 3% to 5% of all pancreatic cancers. Compared to the most common pancreatic cancer—adenocarcinoma (aka exocrine tumors), PNETs have a longer disease course and better prognosis; the 5-year survival rate is 42% for PNETs, but only about 5% to 6% for adenocarcinomas. When PNETs are localized, they can usually be removed by surgery. However, PNETs tend to metastasize, most often to the liver, and present a formidable treatment challenge at this stage. Continue reading…


Lexicon Pharmaceuticals Reports Positive Top-Line Results for Pivotal Phase 3 Telotristat Etiprate Study in Cancer Patients with Carcinoid Syndrome

“Lexicon Pharmaceuticals, Inc. (Nasdaq: LXRX) today announced that the pivotal TELESTAR Phase 3 clinical trial met its primary endpoint, showing the benefit of oral telotristat etiprate in treating cancer patients with carcinoid syndrome that is not adequately controlled by the current standard of care. Telotristat etiprate was discovered using Lexicon’s gene science, based on Nobel Prize-winning technology, and is the company’s first discovery to complete a pivotal Phase 3 clinical trial. If approved, telotristat etiprate would be the first oral treatment successfully developed for carcinoid syndrome and the first addition to the standard of care in more than 16 years.

“Top-line results from the Phase 3 study show that patients who added telotristat etiprate to the standard of care at both the 250 mg and 500 mg doses experienced a statistically significant reduction from baseline compared to placebo in the average number of daily bowel movements over the 12-week study period (p<0.001), meeting the study’s primary endpoint.

“ ‘We are extremely pleased with these top-line results,’ said Lexicon President and Chief Executive Officer Lonnel Coats. ‘Carcinoid syndrome is severely debilitating, preventing many patients from leading active and predictable lives, and unfortunately, a majority of patients will not be adequately controlled over time with the current standard of care. We are committed to working closely with the FDA to file our first new drug application (NDA) and to bring this innovative new treatment to patients whose lives are already impacted by the challenges of cancer.’ “


Lung NETs and Their Treatment


Cancers that arise in the lung are mostly of the type known as NSCLC (non-small cell lung carcinoma). A much smaller proportion of lung tumors arise from neuroendocrine cells in the lungs. These cells (which are also found in most other organs) secrete a variety of hormones that are necessary for normal organ function, as well as for healing after injury or infection. Like other lung cells, neuroendocrine cells may transform to become cancers. Lung cancers that arise from neuroendocrine cells are called pulmonary neuroendocrine tumors (NETs), or lung NETs. Continue reading…