MRI SCREENING FOR PANCREATIC CANCER

MRI could be used to screen for pancreatic cancer in individuals at high risk for the disease, according to early results from a Swedish study, published online on April 8 in JAMA Surgery.

The study addresses a "formidable question" in medical oncology, Mark S. Talamonti, MD, from the Northshore University Health System in Evanston, Illinois, writes in an accompanying commentary.

This noninvasive method of screening for pancreatic cancer "is the state of the art as we have it right now," Dr Talamonti told Medscape Medical News. However, this is "a screening program that you can do in Sweden but probably couldn't do in America."

"In Sweden, with socialized medicine, you can screen patients with MRI because it's a collective cost system," he explained. "In America, that's an awfully expensive screening study."

Screening High-Risk Individuals

About 10% of patients with pancreatic cancer have a related genetic syndrome or a family history of the disease. Several consortia and international societies recommend surveillance of these high-risk individuals. There is no consensus, however, on the best and most cost-effective way to monitor these patients, according to Marco Del Chiaro, MD, PhD, and colleagues from the Karolinska Institute in Stockholm.

The team used MRI to monitor individuals at high risk for pancreatic cancer.

The 24 women and 16 men (mean age, 49.9 years) were referred to the Karolinska Hospital from January 2010 to January 2013 and met the International Cancer of the Pancreas Screening Consortium criteria for high risk.

Of the 40 study participants, 38 (95.0%) had a family member with pancreatic cancer, four (10.0%) had a p16 gene mutation, three (5.0%) had a BRCA2 mutation, and one (2.5%) had a BRCA1 mutation. The BRCA mutations are among the most common genetic mutations associated with familial pancreatic cancer.

For patients with positive MRI results who did not undergo surgery, screening was repeated at 6-month intervals. For patients with negative results on the initial MRI, screening was repeated 12 months later.

During a median follow-up of 12.9 months, MRI revealed pancreatic lesions in 16 patients (40.0%). Of these, 14 were intraductal papillary mucinous neoplasias, which can develop into invasive cancer, and two were pancreatic ductal adenocarcinomas.

Patients with positive MRI results were older than those with negative results (58.6 vs 44.2 years; P < .001).

Five patients (12.5%) underwent surgery — three for pancreatic ductal adenocarcinoma and two for intraductal papillary mucinous neoplasia. The remaining 35 high-risk patients continued to be monitored with surveillance.

"An MRI-based protocol for the surveillance of individuals at risk for developing pancreatic cancer seems to detect cancer or premalignant lesions with good accuracy," Dr Del Chiaro and colleagues conclude.

"The exclusive use of MRI can reduce costs, increase availability, and guarantee the safety of the individuals under surveillance compared with protocols that are based on more aggressive methods," they add.

Lack of Biomarkers Is "Real Problem"

This study confirms that a high-risk group of individuals can be identified and go through an MRI screening program for pancreatic cancer, Dr Talamonti told Medscape Medical News.

However, he suggested that such a program would not work in the United States, because MRI screening is too expensive.

In addition, he pointed out that 90% of Americans who develop pancreatic cancer have no genetic predisposition, so they don't fit the high-risk criteria used in this study.

So far, no biomarkers exist that can be used to screen the general population for pancreatic cancer, which is a "real problem," according to Dr Talamonti. A simple test is needed to screen the general population, "like you do for other cancers," he explained.

"A screening strategy for pancreatic cancer is absolutely imperative because this is one of the most malignant cancers we deal with," he said. In the next 15 years, the incidence of pancreatic cancer will increase by 55%, he pointed out.

"Pancreatic cancer is going to be a major issue in American healthcare in the next 25 years as people live longer and the incidence of pancreatic cancer continues to increase," Dr Talamonti said. "If we don't do better in terms of finding patients at earlier stages of disease, the absolute number of people who die from this disease will increase remarkably."

But, "in the absence of any biomarkers in the foreseeable future, MRI could be a good way to screen high-risk individuals for pancreatic cancer," he added.

The study authors and Dr Talamonti have disclosed no relevant financial relationships.

JAMA Surg. Published online April 8, 2015. Abstract, Commentary