Washington, Nov 21 People with rare pancreatic cancer, called pancreatic neuroendocrine tumours (PNTs), might live longer if treated with radiation therapy, says a study.

The researchers found that this method is effective in achieving local control and palliation in PNTs, despite such tumours being commonly considered resistant to radiation therapy.

PNT is a very rare form of pancreatic cancer that can stay confined to the liver and often cause death from liver damage.

As it is usually unable to be removed by surgery, external beam radiation therapy (EBRT) is an attractive option for managing the disease.

However, the role of EBRT is largely unknown because of the low incidence of this tumour type and, as a result, very few related studies.

Researchers at the departments of radiation oncology and internal medicine, division of hematology/oncology and comprehensive cancer center biostatistics unit at the University of Michigan in Ann Arbor, Mich., wanted to determine if PNTs are not as resistant to radiation therapy as was previously thought.

Thus, they reviewed records from 36 patients with PNTs who were treated between 1986 and 2006 with radiation therapy to 49 sites.

And the researchers found that in 39 percent of patients the tumour shrunk to less than half its pretreatment size after being treated with EBRT.

Also, radiation therapy treatments achieved high rates of local control and 90 percent of patients experienced palliation of symptoms such as pain, nausea, vomiting or obstructive jaundice.

"While this particular type of cancer can have potentially devastating effects on a patient, this study proves that using external beam radiation therapy may permit these patients to live longer, which is a very positive breakthrough for a disease that can have very negative outcomes," said Dr. Theodore S. Lawrence, an author on the study.

The study is published in the latest issue of the International Journal of Radiation Oncology. (ANI)