RCCC chief operations officer Damien Williams has called on the NSW government and the Murrumbidgee Local Health District to increase financial support for the service and make it more affordable for patients.

Mr Williams claims other cancer centres in regional NSW can afford to bulk-bill patients for radiotherapy because "those facilities are heavily supported by the state government" while the RCCC is not.

"This is where we need to have discussions, both at federal and state level: How do we put Wagga on the same financial footing as every other regional area?," he said.

"And credit to the MLHD, they've been very receptive to those discussions. So we hope there's going to be a positive outcome. But certainly now is the time to resolve this."

Patients in Wagga can be left up to $480 out-of-pocket for a course of radiotherapy, which uses targeted X-rays to destroy or shrink cancer cells.

Mr Williams has committed to bulk-bill all patients in Griffith when the RCCC opens its new radiation oncology service there in 2022.

Bulk-billing means a health professional or medical provider charges the federal government instead of the patient and accepts a Medicare benefit as the full payment for the service.

But patients in Wagga have to pay a "gap" fee because here the RCCC charges more than the Medicare Benefits Schedule covers.

Mr Williams said 30 to 40 per cent of the RCCC's patients come from Griffith, who will stop being a source of revenue for the business when their local bulk-billing centre opens next year.

The RCCC, which is located on the grounds of the private Calvary Hospital, is the only place in Wagga that provides radiotherapy and chemotherapy.

Wagga-based medical oncologist David Palmieri said he had worked in other regional centres including Orange and Dubbo where there was "a big difference" in the amount of NSW government support.

"We all would love patients that have no out-of-pocket costs, but to run a cancer centre ... unless we have an adequate amount of state government support, then it's just not viable to be a solely bulk billing service," he said.

Griffith cancer advocate Grant Hearn said the RCCC expansion was an "absolute gamechanger" but he would like to see the service bulk-bill all of its patients.

"It would be good for us but really sad for people in the Wagga area. It would be really good if we could get people treated close to home and not everyone's got the money for this lifesaving treatment," he said.

Mr Hearn suggested the state government could cover the out-of-pocket expenses for patients in Wagga with the money they will save without Griffith radiotherapy patients claiming reimbursement through the Isolated Patients Travel and Accommodation Assistance Scheme.

IPTAAS is a NSW government-funded subsidy program that helps people pay for travel and accommodation costs if they need to travel for specialist treatment.

On Wednesday, The Daily Advertiser requested an interview with an MLHD representative to talk about the RCCC and bulk-billing, and requested a comment from NSW Health. Both requests were declined.

On Thursday, The Daily Advertiser asked NSW Health why it supported radiation oncology services in other regional centres in NSW, but received no response.

Also on Thursday, the MLHD responded to follow up questions from The Daily Advertiser with a statement from chief executive Jill Ludford.

Ms Ludford said all patients admitted to Murrumbidgee public hospitals who required cancer treatment at the RCCC were fully covered by the local health district.

"MLHD has an agreement in place with RCCC to minimise out-of-pocket expenses for non-admitted patients referred to RCCC for treatment, including radiation oncology," she said.

"This includes a financial contribution from MLHD to reduce out-of-pocket expenses. Under the terms of the agreement, patients experiencing financial hardship are offered options including bulk-billing."

Dr Palmieri and Mr Williams said they bulk-billed patients in financial hardship for radiation oncology on a case-by-case basis.

Ms Ludford said the federal government was responsible for funding bulk-billed services and that the RCCC had not approached the MLHD for any contribution towards its new facility in Griffith.

Federal member for Riverina Michael McCormack said doctors and specialists were under no obligation to charge the fee listed in the MBS for the services they provided.

"I understand the RCCC has been working hard towards providing its services with no out-of-pocket expenses, however, the facility cannot run at a loss," he said.

"I support the RCCC to continue to explore avenues in which it can provide its services at the lowest-possible cost to local patients."

Prominent local businessman Daniel Donebus, who chairs the RCCC Community Trust behind the cancer centre, said he would "absolutely" like to see bulk-billing for radiation oncology in Wagga.

"We run a charity that is designed to make this sort of a facility possible here. We just want the community around us to have the best possible services at the best possible value," he said.

"If a no-gap service is available in Griffith, certainly we would be looking at encouraging any possibility of being able to match that here in keeping with our charitable approach to getting cancer sufferers the best possible care."