Amid growing controversy over procedures that exposed 10,000 veterans to the AIDS and hepatitis viruses, the Department of Veterans Affairs is now bracing against news that one of its facilities in Pennsylvania gave botched radiation treatments to nearly 100 cancer patients.

Veterans groups and lawmakers say VA hospitals have permitted these violations because federal regulations allow doctors to work with little outside scrutiny. They say the VA health system, with its under-funded hospitals and overworked doctors, is showing signs of an "institutional breakdown," in the words of one congressman.

An official with the American Legion who visits and inspects VA health centers said complacency, poor funding and little oversight led to the violations that failed the cancer patients in Philadelphia and possibly infected 53 veterans with hepatitis and HIV from unsterilized equipment at three VA health centers in Florida, Tennessee and Georgia.

"Lack of inspections, lack of transparency" were likely to blame, said Joe Wilson, deputy director of the Veterans Affairs and Rehabilitation Commission for the American Legion, who testified before Congress this month on transparency problems in a budgeting arm of the VA.

Wilson said the American Legion is investigating the case of the VA Medical Center in Philadelphia, where doctors gave 92 veterans incorrect radiation doses for treatment of prostate cancer during a six-year span when no peer review or proper oversight measures were in place, the New York Times reported.

Those doctors, whose continuous errors were finally detected last year, were immediately fired from their work at the VA center, but not before putting the lives of the 92 veterans at risk. That news came on the heels of months of investigations into medical lapses that permitted endoscopic procedures like colonoscopies to be performed improperly for years.

Wilson told FOXNews.com that poor funding has aggravated problems, and that money is often misspent on repairs for old facilities and equipment to help manage a construction backlog that has put the VA years behind. He said the aging facilities are incapable of handling or properly operating new technology and equipment.

"The average age of VA facilities is about 49 years," he said. "That's too old. In the private sector the average age of facilities is about 12 years."

The VA Medical Center in Philadelphia is 57 years old. Doctors there were performing a procedure called brachytherapy, in which radioactive seeds the size of rice grains are implanted into organs to kill cancer cells.

But doctors there were sometimes implanting the seeds into the wrong organs, and in many cases gave significantly less radiation than was prescribed -- including during an entire year when their monitoring equipment was broken and they were essentially flying blind, the New York Times reported.

And when one physician, Dr. Gary Kao, was found to have botched a brachytherapy in 2003, he simply changed his surgery plan to make the error appear to be intentional, the Times reported.

Despite the violations that cost Kao his job, some veterans' groups said the general care provided by VA is among the best in the world, and they applauded the department for taking steps to address its problems.

"Our feeling is that the quality of the care is excellent," said Jay Agg, a national spokesman for AMVETS, the American Veterans organization. "However, the fact that it occurred in the first place really points to a lack of oversight, and corrective measures need to be taken."

Both AMVETS and the American Legion welcomed advanced funding that was granted to VA this week, reversing a trend of late funding that has kept the department on tenterhooks for nearly 20 years.

But investigations conducted by the VA last month show that systemic problems remain. Under half of VA centers given surprise inspections had proper training and guidelines in place for common endoscopic procedures.

VA Secretary Gen. Eric Shinseki and senior leadership "are conducting a top to bottom review of the Department," a VA representative told FOXNews.com. "They are implementing aggressive actions to make sure the right policies and procedures are in place to protect our veterans and provide them with the quality health care they have earned."

The representative said that all brachytherapy treatments have been ended at the Philadelphia hospital, and the VA has hired a national director of radiation oncology and developed standard procedures for calculating the accuracy of seed placement.

But veterans advocates say that won't be enough, and they say they haven't seen any evidence of changes that could fix what they call a broken healthcare system.

"How many patients can you see in a day and still give proper care?" asked Jim Strickland, a veterans' advocate and former health care technician who contributes to VAWatchdog.org. "There aren't enough physicians to handle the crisis that the VA faces."

Richard Dodd, a litigator who has represented veterans in lawsuits against the government, said that poor funding has lowered the quality of care and interest from some physicians.

"They're generally under-funded ... and I think the interest of the doctors suffers to some degree," he told FOXNews.com. "Generally speaking, the physicians that work at the VA work there because they have no interest in private health care, and in some situations are unable to find jobs in private industry."

Strickland said care and oversight would not improve until funding is increased and the leadership makes sweeping changes.

In the meantime, he said, "we are doing such a disservice to our veterans."

Lawmakers, who are bristling at that "disservice,"  led congressional inquiries into the endoscopy debacle during hearings last week.

"[T]here is no question that shoddy standards -- systemic across the VA -- put veterans at risk and dealt a blow to their trust in the VA," said Rep. Harry Mitchell, the Arizona Democrat who chairs the House Veterans' Affairs Subcommittee on Oversight and Investigations.

Sen. Arlen Specter, D-Pa., is now gearing up for action over the Philadelphia facility. He wrote to Shinseki Tuesday asking "what allowed such chronic failures to occur" and demanding to know what steps the VA has taken "to ensure that such problems do not occur at other VA hospitals."

Specter called for a field hearing of the Senate Veterans Affairs Committee on Monday, June 29, calling the alleged abuses at VA hospitals "very serious" and promising that they would get a "full and prompt review." A lawyer for Gary Kao said the doctor would appear at the Philadelphia hearing and answer any questions from Specter "fully and completely."