In the last few years, some experts have questioned whether DCIS
(ductal carcinoma-in-situ) is a breast cancer.
DCIS means that the cells that line the milk duct have become cancerous which is where most breast cancers begin. As time passes, the entire lumen of the ducts can be filled with the cancer cells. The duct wall then becomes weakened and the DCIS can break through the duct wall and involve the supporting tissues surrounding the duct which contains blood vessels and lymphatics. Now, the breast cancer is a locally invasive breast cancer. This situation can provide the stage when these cancer cells have the opportunity to travel by these conduits to the local lymph nodes in the axilla. This is analogous to sludge within a water pipe. As the sludge begins to accumulate with time, the sludge fills the entire diameter of the pipe which increases the pressure within the pipe and the pipe bursts with water gushing out.
Some experts believe that some DCIS reverts back to normal cells. However, no one has ever proven this theory! The naysayers who state that DCIS is not a cancer feel that women are being over-treated with lumpectomies and radiation therapy or mastectomies and therefore, increase the cost of medicine. Some of the disbelievers feel at the very most we should follow the DCIS with mammography as these cancers are never destined to bother them. These claimed “medical experts” are not dedicated breast radiologists who have read and followed thousands of women with their mammographic studies and other breast imaging techniques for years to know what they espouse to be true, is in fact, true.
With the advent of modern day mammography in the late seventies, DCIS diagnosis has increased yearly from an average of 3% to an average of 20-30% of all breast cancer diagnoses. This is wonderful news for women because women do not die from the DCIS within the breast. However, we all know this can happen but only when the breast cancer becomes locally invasive breast cancer that spreads beyond the breast to the axilla at which time the cancer could spread to vital organs.
Having been a clinical breast radiologist for over 30 years, I have diagnosed many cases of DCIS. There are some women who have chosen not to have surgery at the time of their diagnosis. It may take years; however, I can attest that all of these cancers progressed to locally invasive breast cancer.
So this monthly KCBC newsletter includes an article about a study recently presented at the American Society of Breast Surgeons annual meeting that negates the naysayers of medical experts who state that DCIS can be followed with mammography as DCIS is never destined to bother them.
Kamilia Kozlowski, M.D.
Medical Director of KCBC
ASBrS: No, we’re not overtreating DCIS
By Kate Madden Yee, AuntMinnie.com staff writer
April 15, 2016 — More than 50% of women diagnosed with ductal carcinoma in situ (DCIS) that is inadequately excised will develop a recurrence of the disease or invasive breast cancer within 10 years. This finding indicates that DCIS isn’t being overtreated, according to research presented at the American Society of Breast Surgeons (ASBrS) meeting in Dallas.
The study addresses a key question in the mammography screening debate: whether DCIS is being overdiagnosed and overtreated, Dr. Sadia Khan of the University of Southern California said at an ASBrS press conference. Some have suggested that DCIS should simply be tracked with regular mammography, but this approach could be dangerous, she said.
“DCIS mortality rates tend to be low, but recurrences may lead to more advanced breast disease and therefore more aggressive treatment later,” Khan said. “Given our results, a ‘watch-and-wait’ strategy would be harmful for many women.”
Watch the margins
Khan and colleagues included 1,919 pure DCIS cases, 720 of which were treated with tumor excision alone. Patients were classified into two groups based on the margin of disease-free tissue surrounding the excised tumor.
Women with margins smaller than 1 mm were advised to have a repeat surgical procedure; of these, 124 refused the additional surgery and were considered undertreated DCIS patients for the purpose of the study. The remaining women, 596, had cancer-free margins of at least 1 mm and were considered adequately treated.
The researchers also categorized women by severity of disease: grades I and II (low) or III (high).
Women with low-grade or high-grade DCIS and inadequate disease-free excision margins had a higher probability of recurrence at five and 10 years postdiagnosis than women who had adequate excision margins, Khan and colleagues found.
|Cancer recurrence in women with DCIS|
|Women with adequate margin excision (≥ 1 mm)||Women with inadequate margin excision (< 1 mm)|
|Low-grade DCIS recurrence rate|
|At 5 years||8%||18%|
|At 10 years||13%||53%|
|High-grade DCIS recurrence rate|
|At 5 years||23%||55%|
|At 10 years||36%||67%|
“These recurrence rates even for excision alone are too high, regardless of grade — and the rates for women with inadequate excision are worse,” Khan said. “It’s unacceptable. We need to continue with the DCIS treatment standard we have now, which is surgery that results in disease-free margins of 1 mm or more.”
The study results are important because many highly publicized DCIS studies have examined survival rates and not recurrence. But recurrence — especially of invasive disease — leads to more radical treatment than DCIS, which can have a significant negative effect on a woman’s life.
“Treatment for invasive breast cancer recurrence might include lymph node dissection, extensive radiation, or mastectomy, which could significantly lower a woman’s quality of life going forward,” Khan said in a statement released by ASBrS. “Preventing women from living with the aftermath of a subsequent treatment for invasive cancer is as important a goal as saving a life.”