What does cancer remission mean?

A diagnosis of cancer carries with it understandable fear and distress. But powerful new therapies that harness our immune defenses—along with new insights into how cancer cells grow and thrive—have improved survival for people with many types of cancer.

Not only can some cancers be successfully treated and potentially “cured,” but other cancers—many of them long considered beyond hope—are manageable as chronic diseases, sometimes for many years.

Understanding the variables of a prognosis

More than 16.9 million Americans who had been diagnosed with invasive cancer (cancer that has spread to surrounding healthy tissue) were still alive as of January 1, 2019, according to the American Cancer Society (ACS). Most of these individuals had been diagnosed with cancer many years ago and were still living without signs of cancer.

If you’ve been diagnosed with cancer, your healthcare provider (HCP) may consider several factors when thinking about your prognosis. (Your prognosis is a way of describing how you might respond to treatment and your chances for recovery.) These include:

• What type of cancer you have and where in your body it first occurred
• The size of the cancer and whether it has spread to other areas of your body
• The biology of the cancer cells themselves. For example, are they aggressive or slow-growing? Do they have certain genes that make them easier to treat?
• Being over the age of 60 with competing health issues, such as heart disease or diabetes, that also may affect your response to treatment

“Prognosis is really a medical term for guessing,” says Erev Tubb, MD, a medical oncologist and medical director at the Mullica Hill Cancer Center in Mullica Hill, New Jersey.

“We’re trying to move away from false hope or false fear,” Dr. Tubb says, referring to oncologists’ efforts to find the balance between promising too little and promising too much. “I try to establish at the outset a realistic expectation as to long-term life expectancy based on the best available data and the patient's overall condition.”

That limited predictability reflects the complexity of many types of cancer.

Learning the terminology of successful treatment

Some cancers respond better to therapy than others. For patients, it can be helpful to understand the terminology HCPs use to describe how well treatments are working against a particular cancer. Cancers can be stabilized, they may go into partial remission or complete remission, or they may progress to worsening disease.

Some of the key terms to understand include the following:

• If a cancer neither grows nor spreads during treatments, that’s defined as stable disease, requiring careful monitoring for any change.
• If tumors shrink by at least 50 percent or more in size, patients are considered to be in partial remission. A partial remission can allow you to take a break from the rigors of chemotherapy or other treatments until a cancer begins growing again.
• Relapse, or cancer’s return, is usually used to describe a cancer that comes back within the first five years of beginning treatment.
• Complete remission describes an absence of all measurable tumors and signs of cancer on imaging tests.

Although some HCPs consider patients “cured” if they remain in complete remission after treatment—that is, free of all signs and symptoms of cancer for five years or more—others avoid the term "cure."

Tubb says he prefers the phrase “continued long-term remission,” even when there’s a high likelihood a cancer won’t come back after treatment. That more guarded assessment allows for the remote possibility of a recurring malignancy many years out. This could happen if treatments leave behind microscopic cancer cells that later grow and divide into new disease.

Ramping up the immune system

As a clearer picture of cancer at the molecular level has emerged over the past several decades, so too have new approaches to treating cancer. These include more precise and targeted therapies that take aim at specific genes inside cancer cells that help cancer grow and spin out of control. HCPs now combine many of these newer therapies with the mainstays of cancer therapy—surgery, radiation, and chemotherapy—to achieve better overall results.

One of the newer types of therapy is immunotherapy, which uses your immune system to “recognize cancer as it should,” Tubb says, thereby rendering cancer cells more vulnerable to attack. Several types of immunotherapy are already in use in clinics. In many cases, these therapies have provided long-term remissions in cancers once considered uniformly deadly, such as advanced lung cancers and kidney cancers, head and neck, liver and kidney cancers, as well as some forms of melanoma, the most lethal form of skin cancer.

One class of drugs called checkpoint inhibitors have been particularly effective. These drugs block a mechanism—known as the “checkpoint”—that cancer cells use to escape detection. The result is that your immune system is better able to find and remove cancer cells. Another treatment strategy involves removing a patient’s own immune cells from the body, altering them genetically so that they can attach to and kill specific types of cancer cells, then re-infusing them into the bloodstream.

These interventions mean treatments may be tailored to each patient. Researchers already have discovered genetic similarities shared across many cancers, Tubb says, which may broaden treatment options for many cancer patients in the future.

“We’ve already seen dramatic changes in treating some cancers,” Tubb says. These advances have made him cautiously optimistic about the progress ahead.

While immunotherapy can lead to long-term remission for certain types of cancers, not every patient responds to it. Researchers, meanwhile, are using knowledge about cancer genetics to find better ways of predicting who is most likely to respond to immunotherapy. HCPs can use these types of methods to better decide which immunotherapy—or combination of therapies—may provide the best treatment option for individual patients.

Though progress is still relatively recent, some HCPs are starting to think that cure rates for some types of cancers have become easier to predict. It’s important to recognize that cancer recurrence may happen, but many experts believe that people with cancer should be able to hear about the good news, too.