Former Senate Majority Leader Harry Reid underwent surgery May 14 to excise a tumor from his pancreas, which was discovered during a routine screening. The veteran lawmaker’s surgeons are positive about his prognosis, and he will soon receive chemotherapy treatment according to a statement from his family.
The American Cancer Society approximates the five-year survival rate for pancreatic cancer is about seven percent. Of the 55,440 people in the United States who will likely be diagnosed with the disease this year, an estimated 80 percent are expected to die from it. Pancreatic cancer has touched public figures in the world of business (Steve Jobs, who died in 2011), actors in Hollywood (Patrick Swayze, who died in 2009), and scientists (astronaut Sally Ride, who died in 2012).
Senator Reid also finds company in some well-known survivors–including Supreme Court Justice Ruth Bader Ginsburg, who underwent surgery in 2009 to remove her pancreatic tumor. The 85-year-old Justice has since received public recognition and admiration for her continued good health and workout regimen.
Beyond surgery and chemotherapy, is there an effective treatment in the works for the disease that, in the United States, accounts for the fourth-highest number of cancer-related deaths?
The advent of transgenic mice, which have been genetically altered to mimic the progression of pancreatic cancer in humans, as led to tremendous progress on this front.
Before researchers can find new treatments, however, they first had to better understand the molecular mechanisms through which pancreatic cancer develops.
Neoplasia, or the growth of abnormal tissue (tumors) involves DNA signaling–which, before the recent discovery of relevant mouse models, was poorly-understood. This knowledge about how pancreatic cancer begins led to studies with mice in which researchers discovered distinct subtypes of pancreatic cancer. Improved understanding of how and why the disease progresses differently according to its molecular classification is important in both diagnosis and the administration of targeted therapies.
Pancreatic cancer is particularly lethal for two reasons: It’s usually diagnosed late, and it responds poorly to treatment. Reid’s surgeons were positive about his prognosis and recovery in large part because his cancer was detected early. Other patients are often less fortunate because pancreatic cancer doesn’t usually cause specific symptoms until it progresses into the late stages. But in Feb. 2018, researchers identified a means of testing mice for pancreatic lesions, which appear before pancreatic cancer develops. This may lead to a diagnostic tool that would allow clinicians to find, diagnose, and treat the disease earlier than is now possible.
In a study published in December 2017, oncology researchers wrote: “Our understanding of the pathogenesis of pancreatic cancer (the manner in which the disease develops) has advanced so greatly in recent years that it would hardly be an exaggeration to refer to the present time as the Pancreatic Renaissance” (emphasis in original.) Unfortunately, they added, gains in the search for new treatments have been less significant.
In just a year’s time, though, scientists’ outlook concerning the search for new therapies seems more positive.
In May 2018, researchers demonstrated how the improved understanding of a disease paves the way for the discovery of new and more effective therapies. It was in mice that researchers first found different subtypes of pancreatic cancer. And then, a potential breakthrough — a study found that altering the genes of mice such that they developed the less aggressive form of pancreatic cancer allowed them to treat it with more success. “Targeting histone modifications and altered gene-regulatory networks to cause a ‘class switch’ to a more differentiated, less aggressive subtype of cancer might provide a promising therapeutic strategy”, the authors wrote.
Pancreatic cancer is stubborn. It’s difficult to find, and even harder to treat. The disease has claimed the lives of well-known people from Joan Crawford to Alan Rickman, and many more people who are not public figures. But progress in the discovery of new medical knowledge about pancreatic cancer, as well as the identification of new treatments which have increased survival rates, has been made possible thanks to animal research.
*Photos above L-R: Alan Rickman, Joan Crawford, Patrick Swayze