Can Cancer Undergo Spontaneous Regression?
Dr. Richard Frank—
For most people, the word "cancer" conjures up fears of a life-threatening disease. Common definitions found on internet sites describe cancer cells as "growing out of control" and relentlessly spreading throughout the body causing harm. The reality, however, is much more complicated. Because I have found in my oncology practice that each patient is unique and each cancer is unique, I was compelled to write my book Fighting Cancer with Knowledge and Hope. I wanted to impart many important types of cancer knowledge, one type being that although some cancers are aggressive and can lead to death, others may not grow very much at all. Still others may actually undergo spontaneous regression! This latter possibility has been of recent interest in the press.
In the New York Times (Oct 27, 2009), Gina Kolata wrote an article entitled, "Cancers Can Vanish Without Treatment, but How?" The impetus for her article were recent medical publications on screening tests for breast cancer and prostate cancer (mammography and PSA testing). She wrote, "Besides finding tumors that would be lethal if left untreated, screening appears to be finding many small tumors that would not be a problem if they were left alone, undiscovered by screening. They were destined to stop growing on their own or shrink, or even, at least in the case of some breast cancers, disappear."
It is presently being debated whether or not screening mammography truly detects an appreciable number of cancers that otherwise would have disappeared on their own. As this impacts the recommended frequency of screening mammography, I will give my take on the current cancer screening debate in a future post. For now, I wish to comment on the concept of the spontaneous remission or regression of cancer. This is defined as a cancer that shrinks or disappears completely without any anticancer therapy.
The concept that some cancers undergo spontaneous regression must be quite foreign and difficult for many people to fathom. But, it is well-established in the medical literature (hundreds of descriptions) and amongst oncologists. In my book I describe the case of a young woman with widely metastatic thyroid cancer that underwent a spontaneous remission. I have cared for many individuals diagnosed with widespread cancer that either stops growing or shrinks to some degree without any conventional or alternative medical interventions.
The most frequently cited cancers that may experience a spontaneous remission include kidney and testicular cancers as well as lymphoma and melanoma (estimated at 1 out of every 400 cases). Perhaps the best studied group is a type of lymphoma referred to as "low-grade, B-cell, Non-Hodgkin's lymphoma." It is well established that approximately 20% of patients diagnosed with this type of lymphoma will experience a spontaneous shrinkage of their disease. It is for this reason that oncologists do not treat these types of lymphoma unless they are causing bothersome symptoms for the patient.
What is the basis of spontaneous remission? In most cases, the individual's own immune system is thought to be able to control the cancer, even fight it into submission. In a few cases, patients' immune cells have been shown in the laboratory to strongly react with their own cancer cells, proving this point. Another reason may be that cancers which undergo spontaneous remission have a special and uncommon biological makeup. This was shown in in a recent report in the journal Blood on 9 patients with chronic lymphocytic leukemia (CLL) who experienced spontaneous remissions. The genetic makeup of their leukemia cells were analyzed and found to be similar in many aspects. This description will hopefully prompt more studies of this type.
The spontaneous remission of an established cancer is not a common occurrence. Still, if researchers could understand why it occurs, what biological features of the cancer or immune system of the affected person lead to remission, then it might lead to breakthroughs in our understanding of cancer. I do think that there should be a national research center that studies patients who experience a spontaneous remission of cancer.
Richard C. Frank, M.D., is director of cancer research at the Whittingham Cancer Center of Norwalk Hospital, medical director of Mid-Fairfield Hospice, and Clinical Assistant Attending at Weill Cornell Medical College. He has been appointed cancer expert for WebMD and was named a “Top Doc” in the New York Metro area by Castle and Connelly.