A new treatment for pancreatic cancer developed by clinical researchers of Norris Cotton Cancer Center at Dartmouth-Hitchcock Medical Center substantially reduces the size of tumors and lowers the risk of local recurrence of the disease. Fifty percent of patients in the study responded to therapy–one of the highest response rates ever seen with pancreatic cancer. Results of the study were published in the December 2005 issue of the Annals of Surgical Oncology.
Researchers, led by oncologist and principal investigator J. Marc Pipas, M.D., were able to reduce the size of tumors so significantly that a number of patients who previously had been categorized as borderline or inoperable could have their tumors surgically removed.
Surgery, and the complete removal of the tumor, is the only curative hope for people with pancreatic cancer, the fourth leading cause of cancer death in the U.S., according to the National Cancer Institute. NCI estimates that of the 32,180 new cases of pancreatic cancer in 2005, 31,800 will die.
The overall five-year survival rate for pancreatic cancer is only 4%, but for patients whose tumors can be completely removed, long-term survival jumps to 18-24%. Detecting the tumor in an early stage is crucial, but pancreatic cancer has few symptoms and is often diagnosed only after the cancer has grown into surrounding tissue or metastasized, making surgery impossible.
“The only way to cure these tumors is to remove them completely,” explains Pipas. “You try to do something to make sure there is no microscopic disease left. If you can’t remove it, the prognosis is poor.”
Traditional treatment for pancreatic cancer is surgery followed by chemotherapy and radiation. The treatment Pipas developed reverses the treatment steps. He administers chemotherapy and radiation in combination first, in order to reduce the size of the tumor and increase the possibility of surgery. The reverse treatment regimen results in many tumors previously considered borderline or inoperable shrinking to a size where they could be surgically removed. In the Norris Cotton Cancer Center trial, 24 patients were treated with short course, high dose chemotherapy of docetaxel and gemcitabine, followed by a combination of radiation and twice-weekly low-dose gemcitabine. Chemotherapy doses in this trial were higher than previously attempted.
Results showed that 50% of tumors shrank by at least a third, including complete disappearance of a tumor in a patient who previously had been judged inoperable. No tumors progressed during treatment.
The ability to shrink a pancreatic tumor is important because in order to eradicate the cancer, the tumor must be small enough to be completely removed without damaging major blood vessels surrounding the pancreas. Seventeen patients in the study underwent surgery, including nine previously considered inoperable or borderline operable. Subsequent follow-up showed that no patient whose tumor was surgically removed had a local recurrence of the disease, and no patient whose disease was considered inoperable had local progression.
Because the treatment Pipas and his team developed is allowing more patients the option of surgery, it is now the standard treatment for pancreatic cancer at the Norris Cotton Cancer Center.
In a new study, Pipas is using gemcitabine and radiation in combination with cetuximab (Erbitux®), an antibody treatment. Norris Cotton Cancer Center is the only center testing this treatment for pancreatic cancer.
“Our goal for therapy is more people to complete resection,” explains Pipas. “That’s going to be the first step to curing patients.”
From Dartmouth Medical School