A Q&A with Rama Gullapalli, MD, PhD; a a physician-scientist in the departments of Pathology, Chemical and Biological Engineering at the University of New Mexico. His research lab focuses on the role of the environment in hepatobiliary cancers. He is also a practicing molecular pathologist with an interest in emerging molecular diagnostics, next generation sequencing and bioinformatics. Email: email@example.com
Q: A recent New York Times op-ed piece from an NYU Langone Health professor urged an aggressive approach to screening for early-stage pancreatic cancer. Despite optimism, the history of cancer screening is rife with trouble, the harms often exceeding the benefits. What do you think is the best way to proceed?
A: Imagine a scenario.
A new cancer test hits the market with some impressive characteristics: a detection sensitivity of 95% and a specificity of an equally impressive 95%. If you were asked the question, “Given a positive test result, what are your chances of actually having cancer?” and you guessed a number of 80 or 90%, you would not be alone. But you’d be wrong.
The key missing information necessary to answer this question is the disease probability among the general population. The number of new cases of cancer detected every year in the U.S. is about 462 cases per 100,000 people. This means that the probability of a new cancer being detected in a member of the U.S. population annually is roughly 0.00462%. Incorporating this information leads to only an 8.1% chance of having cancer for a test that is positive! This is what is called an inverse probability problem. Continue reading…
Treatment for metastatic pancreatic cancer has seen progress in recent years, but outcomes remain poor and treatment advances that can prolong patients’ lives, even for a few months, are eagerly awaited. Two papers published today in the scientific journal Nature Medicine report that a new combination of two drugs that are FDA-approved for other conditions may significantly delay progression of pancreatic cancer in cells and in mice. Furthermore, the first patient treated with this combination experienced a prolonged response that lasted almost 6 months.
In light of these promising results, Cancer Commons is partnering with xCures to track the experiences of patients who choose to try this new combination therapy. Continue reading…
“The federal government is threatening to limit treatment options for doctors fighting cancer. A regulatory decision due Wednesday from the Centers for Medicare and Medicaid Services could undermine the care delivered to the more than 1.6 million Americans who are diagnosed with cancer each year.”
“You’ve probably heard about powerful new cancer medicines like Keytruda and Opdivo. As advertisedon TV, these drugs release brakes on the immune system to make tumors disappear and extend survival in deadly diseases like lung cancer and melanoma. But these agents, called checkpoint inhibitors, work in only a fraction of patients. Scientists are searching for diagnostic tests to predict who will be helped, and who won’t.
“A promising solution comes from Foundation Medicine, a molecular diagnostics company headquartered in Cambridge, Mass. Foundation offers a cancer genome profiling test that evaluates mutations in DNA. With results from its standard FoundationOne panel, Foundation calculates a Tumor Mutation Burden (TMB) score. This quantitative readout―based on the number and type of DNA changes per megabase, a length of DNA―may prove helpful to patients considering immune treatment for many advanced forms of cancer.”
“A couple years ago, Sibel Blau, an oncologist outside of Seattle, was working with the company Guardant Health to test their novel ‘liquid biopsies’ in patients. The idea behind liquid biopsies is both elegant and promising. A doctor takes a blood sample from a patient, and then Guardant looks for tumor DNA floating in the blood, allowing doctors to identify the tumor’s unique mutations and offer a personalized drug regimen—all without an invasive tissue biopsy. Blau was excited to be on board.
“When that study wrapped up, Blau still had Guardant test kits left over, so she offered some to her patients at no cost to them. At this point, Blau was routinely ordering DNA sequencing of traditional tissue biopsies, so some patients got both tests. The tissue DNA test from Foundation Medicine was “routine” in her practice, but even that test had only become available in 2012. The field of cancer DNA has been changing fast.”
“Shortly after his mother died of cancer two years ago, Jeff Ettinger, then-chief executive of Hormel Foods, asked the company’s specialty division to explore how to help people undergoing treatment or recovering from it.
“The timing was right. The Cancer Nutrition Consortium, a group of U.S. cancer researchers, was looking for a food manufacturer to produce nutritional products based on what they saw was a gaping need. Patients undergoing chemotherapy tend to experience extreme fatigue, unintentional weight loss and suppressed appetite and energy.
” ‘You feel like you finished the New York marathon and have no energy to cook,’ said Dr. Bruce Moskowitz, a Florida physician and consortium board member. ‘Many people end up going to a fast-food restaurant to take home a meal, which is not the nutrition they need.’ ”
“After decades of frustration, efforts to develop antibodies that can ferry drugs into cancer cells — and minimize damage to healthy tissue — are gathering steam. The next generation of these ‘weaponized antibody’ therapies, called antibody–drug conjugates (ADCs), is working its way through clinical trials.
“Researchers will gather to discuss this renaissance on 30 November at the Symposium on Molecular Targets and Cancer Therapeutics in Munich, Germany. The improvements come after the first wave of experimental ADCs failed to deliver on its promise.
” ‘Initially there was a lot of excitement, and then slowly many of them did not work,’ says Raffit Hassan, a cancer researcher at the US National Cancer Institute in Bethesda, Maryland. Now, he says, there are two new ADCs in phase III clinical trials, and many more in earlier-stage testing.”
“The promise of personalized cancer medicine is still a long way off, and it’s questionable whether any personalized approach will ever benefit patients to any significant degree, say two researchers writing in a “sounding board” article published online September 29 in the New England Journal of Medicine.
” ‘Patients love the idea that they have a specific mutation in their tumour and that if they have their cancer gene sequenced, there will be a specific and effective drug that targets their mutation,’ coauthor Ian Tannock, MD, PhD, Princess Margaret Cancer Center and the University of Toronto, Ontario, Canada, toldMedscape Medical News in an email.”
“There’s been a lot of excitement about immunotherapy as a tool to treat cancer. But as leading experts gathered here on Sunday, several struck an unexpected note of caution.
“ ‘Be critical,’ said Dr. Philip Greenberg of the University of Washington, who’s also scientific cofounder of Juno Therapeutics, one of the companies leading the search for immune-based treatments for cancer. ‘Don’t believe everything you hear.’ “