A state agency is recommending approval of two proposed mobile advanced cancer imaging systems for Maine, while giving a thumbs down to one proposed for permanent installation by Eastern Maine Medical Center.

The recommendations, barring any challenges in the next few weeks, will go directly to Department of Human Services Commissioner Kevin Concannon for a decision. If approved, the units, called positron emission tomography (PET) scanners, would be the first in Maine.

More than 14 hospitals, including some out of state, have indicated interest in using one of the two mobile PET scanners. Among them are St. Joseph Hospital in Bangor, Maine Medical Center in Portland, Waldo County General Hospital in Belfast, Mid-Coast Memorial in Brunswick and York Hospital.

Bradley B. Ronco, an analyst with the state’s Certificate of Need Unit, which reviews hospital applications for major investments in new technology, wrote in a report issued Wednesday that current use projections support approval of two units, but not three.

The mobile unit applications, submitted by New England Molecular Imaging of Maine in Portland and New England Molecular Imaging in Portsmouth, N.H., each projected serving more patients than EMMC.

Ronco said the ground could shift in support of EMMC’s application in the next few years as PET technology gains acceptance for more uses. Right now, for instance, PET is seen as having a role in detecting breast cancer, but Medicare doesn’t reimburse for its use with that disease, Ronco said in an interview Thursday.

“These applications made projections as much on current reimbursement as it was on the utility of PET,” he said.

Until those issues align, however, EMMC’s application won’t muster his support because “given our lack of experience with PET it seems reasonable to accept these projections for the near term,” Ronco wrote.

EMMC officials said they weren’t aware of the state’s decision and therefore would not comment on it Thursday.

In another application before the Certificate of Need Unit, EMMC is locked in a battle with St. Joseph Hospital over whether both will offer cardiac catheterization services. Despite that long-running debate, St. Joseph CEO Sister Mary Norberta said in November that EMMC, with its cancer center, probably merited PET as well. She endorsed one of the mobile applications, however, because it could be moved to rural hospitals as needed.

Also supporting EMMC’s application was the town of Orono. Leaders sent a letter to Ronco because of the University of Maine’s interest in using a cyclotron that was expected to be part of EMMC’s PET application. The support became moot, however, after EMMC decided against asking for that piece of equipment, Ronco said.

Ronco’s unit, which is part of the Department of Human Services, is charged with determining if medical proposals will be adequately used to justify the expense of building them. PET is such a new technology that insurance reimbursement hasn’t kept up, he said. However, PET might save money in the future by reducing invasive surgery to look for certain abnormalities, he said. The proposed scanners cost $2 million to build and $2 million annually to run.

“I’m just impressed with the potential [PET] has in improving the efficacy of cancer treatment,” Ronco said. “It’s just phenomenal technology.”

Unlike a magnetic resonance imaging (MRI) system, which just looks at structures in a body, a PET scanner can look at the metabolism of a structure. A cancerous tumor, which inefficiently processes glucose, can be diagnosed when the scan detects glucose flagged by a radioactive marker being pulled toward the structure.