Pamela A. Popper, Ph.D., N.D.
Wellness Forum Health
The most frequent form of cancer diagnosed with mammography, ductal carcinoma in situ (DCIS), is a very early-stage cancer, and some do not even think it should be referred to as “cancer.” Most women may be better off not knowing about it, because it usually does not progress to invasive cancer. Yet women with DCIS are told they have “cancer” and are commonly treated with lumpectomy, mastectomy, radiation, and drugs.
The justification for treating DCIS is that if left untreated, DCIS will progress to invasive cancer. But research does not support this stance. Studies of thousands of women who had breast biopsies in the 1950’s and 1960’s and were untreated show that the risk of developing invasive breast cancer or dying from it are low. For a group of women in Tennessee, 25% of women with DCIS developed invasive breast cancer within 10 years of their biopsy.[i] For a group of women in Italy, only 11% of women developed invasive breast cancer in the 20 years following biopsy.[ii] This means that an average of 82% of women did not develop invasive breast cancer. For those who did, invasive cancer developed over a period of several years, making watchful waiting a reasonable strategy. This would result in treatment only for those women who developed cancer, a small percentage, while the rest of the women would be left alone.
As for reducing the risk of death from breast cancer, a study comparing the life expectancy of women with breast cancer to similar-aged women without it showed that women with metastatic breast cancer were 12 times more likely to die than women of a similar age who did not have it. Women with early-stage breast cancer were two times more likely to die. But women with DCIS were between 20% and 30% less likely to die than their counterparts without breast cancer.[iii] This provides further evidence that DCIS is not life-threatening cancer, that most women are over-treated for it, and that most women might be better off not knowing that they have it. A diagnosis of DCIS has little to no effect on life expectancy.
The most important reason for healthy people to have a screening test is to reduce the risk of dying of a disease or of co-morbidities related to it. The rationale for early detection of breast cancer is that early detection leads to effective treatment which then reduces the risk of developing more serious or late-stage and potentially fatal cancers. But studies show that most women with DCIS do not develop invasive breast cancer. Furthermore, over 500,000 women have been diagnosed with DCIS since the 1980’s when mammograms became common, but this has made almost no difference in the incidence of late-stage cancer. This means that either treatment for DCIS is incredibly ineffective, or more likely, that DCIS is not really cancer.[iv]
Women should be made aware of these data before consenting to a mammogram, since mammograms are more likely to detect DCIS than aggressive cancers, and they certainly should be made aware of these data before consenting to treatment for DCIS. Surgery, radiation, and drugs have side effects, some of which can be life-threatening, and cannot benefit people who do not have cancer.
It’s time to re-think cancer screening and the very definition of cancer, but there is very little appetite for doing this since screening and treatment are multi-billion dollar industries. It is up to patients to say no and to dry up the demand for both.
[i] Page D, Dupont W, Rogers L et al. “Continued Local Recurrence of Carcinoma in Situ 15-25 Years After A Diagnosis of Low-Grade Ductal Carcinoma in Situ of the Breast Treated Only by Biopsy.” Cancer 1995 Oct 1;76(7):1197-200
[ii] Eusebi V, Foschini M, Cook M et al. “Long-Term Follow-up of In Situ Carcinoma of the Breast with Special Emphasis on Clinging Carcinoma.” Semin Diagn Pathol. 1994 Aug;11(3):223-35
[iii] Ernster V, Barclay J, Kerlikowske K et al. “Mortality among Women with ductal Carcinoma In Situ of the Breast in the Population-Based Surveillance, Epidemiology, and End Results Program.” Arch Intern Med. 2000;160(7):953-958.
[iv] Welch G. Should I Get Tested for Cancer: Maybe Not and Here’s Why University of California Press 2004 pp 84-85