Blue Shield member Tom DiCioccio

Tom DiCioccio of Oceanside owes nearly $20,000 for his cancer surgery this year after Blue Shield switched him into a policy with fewer providers. The insurer agreed to pay his bills after The Times asked about the case. (Don Bartletti / Los Angeles Times / June 27, 2014)

Frustration and legal challenges over the network of doctors and hospitals for Obamacare patients have marred an otherwise successful rollout of the federal healthcare law in California.

Limiting the number of medical providers was part of an effort by insurers to hold down premiums. But confusion over the new plans has led to unforeseen medical bills for some patients and prompted a state investigation.

More complaints are surfacing as patients start to use their new coverage bought through Covered California, the state's health insurance exchange.

"I thought I had done everything right, and it's been awful," said Jean Buchanan, 56. The Fullerton resident found herself stuck with an $8,000 bill for cancer treatment after receiving conflicting information on whether it was covered.

"How am I going to come up with that much money?"

Insurers insist that pruning the network of doctors is a crucial cost-cutting measure and a major reason that so many Californians could find affordable coverage in the health law's first year.

"These narrow networks are making a huge difference in terms of affordability," said Mark Morgan, president of Anthem Blue Cross, a unit of industry giant WellPoint Inc. "We found in convincing numbers that people value price above all else."

But regulators, lawmakers and consumer advocates are pushing back to ensure patients know what they're giving up in return for lower rates — and don't run into unnecessary roadblocks to care.

This month, the California Department of Managed Health Care began investigating whether two major insurers, Anthem Blue Cross and Blue Shield of California, are violating state law related to inaccurate provider lists and offering timely access to treatment.

Regulators say customers of those two companies, which account for nearly 60% of Covered California's enrollment of 1.4 million people, have complained the most about provider-related issues.

Consider Buchanan, who lost her previous coverage when her insurer dropped out of the individual market last year. She was diagnosed with breast cancer in July, so she opted last fall for a Platinum plan, the highest level of benefits on the state exchange, from Blue Shield.

Buchanan started treatment at UC Irvine Medical Center in the fall, and her oncologist there took her new Blue Shield insurance in January and February. Then the day before her lumpectomy, UC Irvine called to say her insurance wasn't accepted after all. She initially canceled the surgery, but her family and friends told her she shouldn't risk waiting.

Buchanan is paying $200 a month on her $8,000 surgery bill. UC Irvine said there's been considerable confusion among Blue Shield customers with exchange plans.

Tom DiCioccio, 64, of Oceanside faced a similar predicament after getting diagnosed with cancer in his lymph nodes. The retired shoe designer owes nearly $20,000 for his cancer surgery this year after Blue Shield switched him into a policy with fewer providers.

The insurer covered his care at Cedars-Sinai Medical Center on his prior plan, and he said Blue Shield never advised him of any major changes. Like many consumers, he said it was nearly impossible to get information from the company's call center or website.

After being contacted by The Times, Blue Shield reversed itself and told DiCioccio it would take care of his bills. The San Francisco insurer said DiCioccio shouldn't be penalized for going out of network because he was already undergoing treatment before his policy changed.

DiCioccio was unimpressed. "What about everyone else? There are so many other people like me," he said.

Blue Shield stood by its handling of Buchanan's case because it said she was advised UC Irvine was out of network.

"People need to be very diligent in deciding where to go," company spokesman Steve Shivinsky said. "We are trying to do our part to educate people, but it's a big task when the market has been totally turned upside down."

In all, customers of Blue Shield in Covered California have filed 590 complaints with the state this year through early June, and 97 of those gripes are about the insurer's networks.