“Treatment with cabozantinib was tied to objective tumor responses and promising progression-free survival (PFS) in patients with advanced carcinoid and pancreatic neuroendocrine tumors (pNET), researchers reported here.
“With a daily cabozantinib (Cabometyx, Cometriq) treatment, 15% of 20 patients with pNET achieved partial response (95% CI 5-36%) and 75% achieved stable disease (95% CI 53-89%), which was the the trial’s primary endpoint, according to Jennifer Chan, MD, MPH, of the Dana-Farber Cancer Institute in Boston, and colleagues.”
“In a phase II study reported at the 2017 Gastrointestinal Cancers Symposium, the tyrosine kinase inhibitor cabozantinib (Cometriq) was evaluated in advanced carcinoid and pancreatic neuroendocrine tumors. Radiographic responses to therapy were observed in both tumor subtypes, and compared to other drugs historically used in this setting, progression-free survival data were encouraging, according to Jennifer A. Chan, MD, of Dana-Farber Cancer Institute, Boston.
“Vascular endothelial growth factor (VEGF) pathway inhibitors have shown activity in advanced neuroendocrine tumors. Recent studies have suggested that activation of the MET signaling pathway may also play a role in the growth of neuroendocrine tumors. Increased expression of MET correlates with decreased overall survival in pancreatic neuroendocrine tumors, Dr. Chan noted.”
“In a single-arm phase II study, cabozantinib demonstrated clinical activity in patients with advanced carcinoid and pancreatic neuroendocrine tumors (pNETs). Partial responses (PRs) were observed in 15% of each cohort treated with cabozantinib and stable disease was the best response in about two-thirds of patients.
“Median progression-free survival (PFS) exceeded 20 months in the pNET cohort and was >30 months in the carcinoid tumor cohort, said Jennifer A. Chan, MD, at the 2017 Gastrointestinal (GI) Cancers Symposium.”
Neuroendocrine tumors of the digestive system (GI-NETs) can arise in different parts of the digestive tract. GI-NETs originating in the ileum, duodenum, and appendix are known as midgut NETs, and tumors of the stomach, colon, and rectum are non-midgut NETs. Many of these tumors are functional; that is, they produce a variety of hormonal substances that cause serious, debilitating symptoms. Continue reading…
“Several recent studies have shown promise for the treatment of pancreatic NETs (pNETs). In the phase II CALGB-80701, which investigated the addition of bevacizumab (Avastin) to a treatment paradigm of everolimus and octreotide (Sandostatin) LAR in patients with locally advanced or metastatic pNETs, bevacizumab extended progression-free survival (PFS) by more than 3 months compared with everolimus and octreotide LAR alone.
“Response rate was also higher in the bevacizumab arm, with a 31% response to everolimus plus bevacizumab versus a 12% response in the control arm. Toxicity, however, was significantly higher in the bevacizumab arm.”
“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.”
“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.”
“One form of pancreatic cancer has a new enemy: a two-drug combination discovered by UF Health researchers that inhibits tumors and kills cancer cells in mouse models.
“For the first time, researchers have shown that a certain protein becomes overabundant in pancreatic neuroendocrine tumors, allowing them to thrive. They also found that pairing a synthetic compound with an existing drug provides a more effective anticancer punch than a single drug. The findings were published recently in the Journal of the National Cancer Institute by a group that includes Rony A. François, an M.D./Ph.D. student working with Maria Zajac-Kaye, Ph.D., an associate professor in the UF College of Medicine’s department of anatomy and cell biology.
“Finding new treatments is critical because less than 5 percent of patients with pancreatic neuroendocrine tumors respond to everolimus, the most commonly used pharmaceutical, François said. Neuroendocrine tumors, which form in the hormone-making islet cells, account for 3 percent to 5 percent of pancreatic malignancies and have a five-year survival rate of about 42 percent, according to the National Cancer Institute. Pancreatic neuroendocrine tumors are increasingly common, which medical experts and researches have attributed to better diagnostic imaging, an aging population and heightened awareness of the disease stemming from the 2011 death of Apple Inc. co-founder Steve Jobs.”
Neuroendocrine tumors (NETs) can arise wherever neuroendocrine (hormone-producing) cells are found—which is in most organs. Most NETs (65%-70%) are gastroenteropancreatic, or GEP, arising in different gastrointestinal organs. GEP-NETs are most commonly found in the small bowel (including the appendix), stomach, and rectum. Still, NETs in general are rare, which complicates the development of new treatments and identification of the genetic drivers of these cancers. Treatment of GEP-NETs is clearly an unmet medical need, and is now even more urgent because their incidence has been on the rise in the last 20 years. Continue reading…