FORTUNE – Not long ago, the word “cancer” was off-limits, among friends, at home, and certainly at the office. Whether it was out of superstition, fear, confusion, or respect, most talk about the disease was done in hushed tones.
Today, as the survival rate climbs, the decisions people make after diagnosis — both personal and professional — have evolved significantly. Suddenly, for many (but not all), the question is not, “How do I leave work for good?” Instead, it’s “How long do I take off?” or “Do I have to take off at all?”
Working after a cancer diagnosis has become fairly common, according to a new survey conducted by the nonprofit group Cancer and Careers. One in four people with cancer who were surveyed said they continued working to keep their health insurance. Twice as many said they worked to keep things “as normal as possible.” And two-thirds who were surveyed claimed they felt well enough to stay on the job. The Harris Interactive survey queried 400 adults diagnosed with cancer who were working.
“Work provides them a respite from cancer-land,” said Kate Sweeney, executive director of Cancer and Careers, a nonprofit that offers resources to workers.
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Some 45% of workers said they took no time off after their diagnosis and kept working, while 31% said they took anywhere between a few weeks to five months off, according to Cancer and Careers’ survey.
As more employees choose to continue working, more employers must grapple with relatively new territory. HR consultant Margaret Spence says she has seen all manner of responses from companies with workers diagnosed with cancer. Spence says it’s easy for workers and firms to feel trapped. “Employers are caught between a rock and a hard place,” especially since they don’t always have a complete picture of the worker’s health, she said.
A year ago, Spence’s husband was diagnosed with a rare form of cancer — and she got to experience the cancer-career conundrum up close. The couple considered relocating temporarily to New York or Texas to be closer to high-quality treatment but ruled that out because of the associated costs.
“He needed to keep working,” Spence said. “It was the one thing that kept him connected” to the world amid rounds of radiation.
An estimated 13.7 million people have had cancer and were living in the U.S. in 2012, and that’s expected to grow to 17.8 million by 2022, according to the American Cancer Society. About one-third of female cancer survivors and one-quarter of male survivors are under 60 years old, while another 25% are 60 to 69.
Cancer does take a toll on people’s careers. Survivors are 4-5% less likely to hold jobs and work up to four hours less than similarly aged adults without a history of cancer, according to research from Penn State. And, perhaps without surprise, those who suffer from recurrences of cancer work less and take longer breaks from work.
Workers today are more willing to share the details of their disease with coworkers and bosses than they were 10 years ago, Sweeney said. A decade ago, many people kept their cancer a secret at work, she claims.
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Still, not everyone is comfortable discussing illness at the office. Spence told of a client of hers who was a hard-working senior manager at an agricultural company. One day, she left packages for Spence and a few others before leaving for what her colleagues thought was a week’s vacation. She checked into hospice and died three days later. “I was in shock when I found out. I had no idea she was sick,” Spence said.
Spence thinks employers fall into two main categories: those that follow sick leave or disability policy and laws rigidly and those that treat workers like individuals and work with them during their treatment. Many of the decisions are made one-by-one based on the employee’s experience, value, and prognosis.
“It’s very personal. If an employer really likes the employee, that’s when they tend to be more flexible or more sympathetic,” said Kate Brown, director of support and advocacy at Lungevity, a lung cancer support nonprofit.
Lungevity’s Brown says that some workplaces organize “meal trains” where different people deliver a meal each week to a colleague with cancer. Another, she says, bought a special telephone with speakers so a worker whose voice was hoarse and dim could continue to field calls.
Most corporate policies are based on federal laws and requirements, including accommodations mandated by the Americans with Disabilities Act. Cancer was added to the list of illnesses covered by the ADA on Jan. 1, 2009, and the EEOC issued guidelines for it a couple of years later.
Businesses with more than 50 workers are required to give Family and Medical Leave to employees who have cancer. Under the FMLA, workers are entitled to 12 weeks of unpaid time off to care for a child, spouse, or themselves. The employer is expected to continue health insurance and hold a comparable job open for these employees.
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At Cancer and Careers, the staff is starting to hear more from employers looking to help workers through their cancer diagnosis and treatment. Sweeney urges firms to be flexible and to allow staff to work at home during chemotherapy or radiation. Some companies are creating “shared vacation pools” so that workers with extra days can donate them to colleagues battling cancer or other serious illnesses.
Employers want to hang onto experienced staff, so the percentage of U.S. firms that offer cancer insurance policies has inched up to 34% (from 28% in 2008), according to the Society of Human Resource Management.
“These employees are valuable,” and employers often want to find ways to bring them back to work, said Tom Parry, president of the Integrated Benefits Institute, an independent research organization. Other workers are watching carefully how the employer treats them. “When employers do the right thing with someone with cancer, that is a very important message” that resonates with many workers, he said.