Line between cancer treatment, overtreatment isn’t always clear

August 12, 2013 | by

Some cancer screenings have been criticized for leading to overdiagnosis and overtreatment, with a recent report casting particular doubts about the treatment of ductal carcinoma in situ, or DCIS. But, as one City of Hope expert points out, determining which condition is threatening, and which is safe, is rarely clear-cut.

In cancer, determining which cases might become dangerous isn't easy. In ductal carcinoma in situ, for example, doctors must assess whether breast cancer currently confined to the milk ducts is likely to spread. Shown here: breast cancer cells.

In cancer, determining which cases might become dangerous isn't easy. In ductal carcinoma in situ, for example, doctors must assess whether breast cancer currently confined to the milk ducts is likely to spread. Shown here: breast cancer cells.

“For each patient, we only have one chance to get it right,” said Steven Chen, M.D., associate clinical professor of breast and endocrine surgery. “If there’s only a 20 percent chance that DCIS will develop into an invasive cancer, it may seem low in abstract, but it’s 100 percent for some person.”

DCIS is a noninvasive condition in which the abnormal cells are limited to the lining of the breast’s milk ducts. There, they’re not considered dangerous unless they break through the breast tissue and spread to the lymph nodes and other organs. In fact, the condition is often referred to as Stage 0 breast cancer because of its limited risk of spread.

And yet, the condition is often treated with surgery and radiation.

As a recent NPR story described the condition: “DCIS is a touch point of the overdiagnosis debate. Nearly 70,000 women are diagnosed with it each year. Before mammography screening, only about 3 percent of breast cancers were DCIS. Now the condition accounts for a third of all "breast cancers."

Sometimes, the word “cancer” frightens patients so much that they decide to undergo surgery. Between 1998 and 2005, the mastectomy rate for women diagnosed with DCIS rose 188 percent among women given a new diagnosis of DCIS in one breast, according to the Journal of Clinical Oncology.

The National Cancer Institute (NCI) recently assembled a group of researchers and scientists to review potential overdiagnosis and overtreatment of some cancers such as DCIS. Overdiagnosis occurs when tumors are detected that, if left untreated, would not cause harm or death. Sometimes, people “overdiagnosed” get treatment they don’t actually need. The findings from NCI’s group of researchers were published recently in JAMA, a journal of the American Medical Association.

The panel suggested changing the language used to describe lesions to help patients understand that not all malignancies are deadly. In the case of DCIS, the group recommended that the term “cancer” not be associated with the condition; instead, it said, the condition should be renamed to exclude the word “carcinoma” completely.

Chen knows that a large number DCIS cases will never develop into an invasive cancer and that many patients ultimately might never have needed treatment. The problem, he said, is that physicians don’t yet have the technology to determine which abnormalities will become invasive. So, he said, for their patients, they often must assume that they will.

The medical community is working to find better ways to predict the aggression of individual cases, Chen said. But doctors currently don't have the comfort level needed to let people go untreated, even if statistics show there’s only a slim chance the condition will form into an invasive cancer.

“For right now, the standard recommendation remains that these diagnoses should be treated, at least until we have better ways of classifying those that do not need treatment in a reliable way,” Chen concluded.

Further, Chen said, instead of changing medical terminology to ease patients, perhaps having better communication between doctors and patients would be more valuable.

“What’s more important is how doctors interact with patients on an individual basis,” said Chen. “We should counsel our patients more carefully to give them a better understanding of DCIS.”