As much as any disease, cancer stokes a deep sense of dread, even doom. Physicians see the fear welling in the eyes of their patients, hear it catching in their voices.
"The word cancer still carries with it the specter of death and suffering," said Dr. Donna Greenberg, director of psychiatric oncology at Massachusetts General Hospital. "It's like a monster is coming into your house."
But often, a patient's perception of peril - whether before a screening test or upon a definitive diagnosis - exceeds the genuine risk and can cloud treatment decisions.
The fear is a reflection, in many respects, of what science has wrought in recent decades: More cancers than ever are being diagnosed, and they're being found earlier and earlier. Tumors that would have gone unnoticed and untreated in an earlier era are now identified and addressed, even when the benefits aren't fully clear.
"We've exaggerated the efficacy of our treatment and prevention at the same time we've spread fear of cancer," said Dr. Robert A. Aronowitz of the University of Pennsylvania, who has studied the history of cancer extensively. "And it's led to a lot of individual and policy level mistakes."
A February study from the Dana-Farber Cancer Institute, for example, showed that women diagnosed with a limited form of breast cancer substantially exaggerate prospects that the cancer will spread, potentially killing them. And researchers who conducted another study released last month found that men's concerns about prostate cancer eased - once they received information via a sophisticated Internet program.
Those studies underline a growing recognition among cancer specialists: Information is not only power. It can also forge hope.
That's exactly what happened when parents whose children were gravely ill with cancer received a more detailed description of how the disease might progress. The families getting the most information reported the greatest degree of hope, even in the face of a grim prognosis.
"Hearing news about a cancer diagnosis is alarming," said Holly Prigerson, director of Dana-Farber's Center for Psycho-oncology and Palliative Care Research. "There's a need for mechanisms in place to make sure people aren't freaking out. There's freaking out that's justified, and freaking out that's not justified."
Debi Kimsey got the news nearly a decade ago in her adopted home of Honolulu, not long after her 40th birthday. We've found something on your mammogram, the doctor's office told her. We need to do further testing. They did. Diagnosis: ductal carcinoma in situ, a condition confined to breast ducts and marked by unchecked growth of cells.
She sat on the exam table. The cancer doctor sat on a chair. He leaned in.
"And he said, 'I have to tell you - this is absolutely, 100 percent curable at this state,' " Kimsey, an interior designer, recalled. "It still was scary, but I knew it was going to be OK, although it did take me about a year to really believe it."
When patients receive a diagnosis of cancer, it is that word - cancer - that rebounds across the room, suffocating all attempts at nuance.
"The glass may be 99 percent full," said Dr. Ann Partridge, a breast cancer specialist at Dana-Farber, "but they grab onto the 1 percent risk."
The anxiety ignited by a diagnosis of cancer was palpable in a recent study that Partridge directed. Eastern Massachusetts women diagnosed with ductal carcinoma in situ were asked in a survey to assess the risk posed by the condition.
Of the 487 women who responded, 28 percent said it was moderately likely that the ductal carcinoma in situ would migrate elsewhere in their body. In truth, the risk is less than 1 percent. Similarly, the women overestimated the chances that the condition would return to their breast, even though treatment makes the prospects of a recurrence quite remote.
Communicating the risks of cancer and the benefits of treatment proves to be a complex, time-consuming proposition. In large part, that's because there are so many kinds of cancer with so many kinds of treatment. Some, such as pancreatic cancer and certain brain tumors, are almost always lethal. Others, much less.
"There's not always a right answer for what we do," said Dr. Lois Ramondetta, an oncologist at M.D. Anderson Cancer Center in Houston.
And talking about treatment options can turn into a walk through a thicket of statistics. With ductal carcinoma in situ, for example, patients might be told that if they opt to take a drug called tamoxifen, it will reduce by 50 percent their chances of later developing invasive cancer in the same breast.
That's true, but it's also somewhat misleading. Regardless of whether they take the pills, the overall risk of invasive cancer in the same breast is low. It's about 2 percent for women who take the drug, 4 percent for those who don't.
And, like all medications, there are side effects, including, in a small number of patients, a chance that the drug will cause uterine cancer, said Dr. Karin Hahn, an M.D. Anderson oncologist.
"Some patients look at you like you've grown five heads," Hahn said. "Why if you've just treated them for breast cancer would you offer them a drug that has a small risk of causing uterine cancer?"
So these are the questions Hahn poses to patients: "Are you the kind of person who's not going to be able to sleep at night if you don't take a pill that might reduce your risk of having breast cancer in the future? Or are you the other 50 percent of people who are not going to sleep at night because you're going to worry about the side effects of taking this pill?"
What's important, specialists said, is for doctors to ask those questions, to make sure patients are absorbing what they're being told.
"One of the challenges for physicians is that they don't have much time, and they're not about to get more time in the future," said Dominick L. Frosch, a specialist in health communication at the University of California at Los Angeles.
That's why researchers are increasingly experimenting with alternative ways of providing comprehensive, digestible information about cancer to patients. Frosch, for instance, led development of Internet-based programs designed to help men over the age of 50 decide whether they wanted to be screened for prostate cancer and what treatments they might choose if diagnosed with the disease.
Prostate cancer is often a slow-moving disease that, ultimately, does not cause a man's demise. Conversely, treatments can result in impotence or incontinence.
In a study, men were asked to access different Internet programs. Frosch discovered that men assigned to the more interactive programs reached higher-quality decisions about screening and treatment options than men who reviewed more conventional websites such as the American Cancer Society's.
"What men really need," Frosch said, "is prescription-strength information."
Of course, the same is true for women. So that's exactly what Suzanne Fountain sought when she was diagnosed with ductal carcinoma in situ. She already knew something about the condition even before being told she had it: Her sister is Debi Kimsey.
Kimsey chose to have the small growth removed followed by six weeks of radiation. Fountain, who lives in Boston, opted for minor surgery, too, but followed it with several years of tamoxifen.
In both sisters, the cancer went away and never came back. Information, the women said, guided them to their decisions - and quelled their fears. Still, Fountain acknowledged, she experiences the occasional spasm of anxiety about cancer's return.
"If I do have an ache or pain, is it sort of in the back of my mind? Yeah," said Fountain, director of the Jimmy Fund at Dana-Farber. "But I don't spend my life angsting over it. You just deal with it and move on."
Stephen Smith can be reached at stsmith@globe.com.
