During and after two courses of chemotherapy and four surgeries to treat her melanoma, Donna Piunt suffered side effects including nausea, vertigo, and cognitive issues.

But the Pottstown woman, 54, says her most difficult cancer burden was financial, not medical.

Her illness and treatment left her unable to work, and her husband, Stefan, couldn't make up for the loss of her income, even picking up as much overtime as he could at his job as a machinist. Two years ago, the couple lost their house and eventually filed for bankruptcy.

"Cancer wreaked havoc on our finances," she said. "You feel like you're in quicksand, and you have no one to pull you out. Your mind goes crazy, thinking: What can we sell? How are we going to make the next payment? I remember not being able to sleep the whole time."

The Piunts are not alone. Financial toxicity, defined as the cost burden of cancer care, can create stress and a poorer quality of life for patients already struggling with managing life-threatening disease.

Toxic levels of financial stress can arise from a variety of sources: job loss, drug costs, medical bills not covered by insurance. These costs can reach into the many thousands of dollars, but even comparatively small expenses can affect care. One study, for example, showed that when co-pays reached more than $50 for the cancer drug imatinib (Gleevec), there was a 42 percent increased likelihood that patients would skip taking the drug.

"It's increasingly important for oncologists to talk with their cancer patients about finances," said Yu-Ning Wong, associate professor in medical oncology at Fox Chase Cancer Center, who researches the impact of higher costs on patients. "It's an exciting time. We have new drugs that offer benefits for patients that we didn't have before. But the drugs are expensive, and people are seeing higher out-of-pocket costs."

Yet the topic of money can be sensitive for both doctor and patient. Doctors often don't know how costs vary according to a patient's insurance status. Patients may fear their care will be compromised if they ask about money.

But financial toxicity itself can affect patients' health.

A study by Duke University researchers showed that nearly half of the 1,000 cancer patients surveyed cut food and clothing costs to pay for cancer care. About half were dipping into savings to pay for care, and about 17 percent were selling their possessions. Fallout from financial toxicity included skipping prescribed medications, delaying care, and missing appointments.

"Our patients are exquisitely sensitive to these costs that they face every week or every month while they are receiving cancer treatments," says S. Yousuf Zafar, a medical oncologist at Duke University Medical Center.

But talking about financial toxicity may help. In a soon-to-be-released study, Zafar found that, among the minority of patients who do talk to their doctors about costs, just over half said their out-of-pocket costs were decreased as a result of that conversation. Most of these patients said their care didn't change after they brought up the subject.

"This comes down to patient advocacy. Maybe it's because doctors are advocating for patients with the insurance company," Zafar said, "or maybe these patients are being linked up with patient-assistance programs sooner rather than later."

Zafar noted that doctors should become as versed in sensitive financial discussions as they are in talking about medical care.

"If we can warn a patient about potential physical toxicities that they might face from a treatment we've prescribed to them, there is no reason why we can't warn them that they may expect financial costs as well," he said. "Preparing patients for costs, even if we can't eliminate the costs, can help."

Another reason doctors may hold back from discussing costs of drugs is a lack of price transparency, he said.

"Cancer care is difficult, multidisciplinary care that can span months, if not years, with different treatment modalities being phased in and out during the course of that treatment, so placing a price tag on that care becomes a challenge."

Still, this lack of transparency shouldn't stop the discussion, he said.

"Asking a simple question like, 'Do you have prescription-drug coverage?' can go a long way in saving a patient hundreds if not thousands of dollars, without knowing any details about how much the drug costs, about where the patients are in their insurance cycle, or how much they're going to get billed."

Jonas de Souza, assistant professor of medical oncology at the University of Chicago Medicine, is working on a questionnaire to measure patients' risk for, and ability to tolerate, financial stress.

"We tell patients this drug causes hair loss in 30 percent of patients; why can't we have data on how this particular treatment causes financial distress in 20 percent of patients?" de Souza asked.

He hopes the final version of the questionnaire will give doctors information they need to more easily bring up finances and their impact on quality of life.

"Patients can be embarrassed to talk about costs; doctors don't want patients to think we only care about money. There are multiple barriers to talking about costs, but we need to do it," said de Souza.

"Financial toxicity will eventually reach other diseases," he said, noting costlier new drugs for cholesterol, rheumatology, and MS.

"As co-payments go up, people's compliance with medicine goes down," Wong said. "We need to make sure that insurance plans encourage patients to make the right decisions for health care, that we try to put patients in touch with co-payment assistance foundations and charities. There are some very important support services out there. Not everybody is eligible, but not everybody knows about them.

"Cancer patients are particularly vulnerable," he said. "So much is happening to them in such a short period of time when they're under so much stress."