SINGAPORE - I remember vividly my encounter with Yvonne (not her real name) when she first stepped into my clinic.
The 36-year-old teacher produced her biopsy results and said in a level tone: "I'd like to have your opinion if this is really cancer."
I realised the results of the test on her tissue sample were dated two years ago.
"Have you received further treatment?" I probed.
"No. I was told this is early. I don't think this is cancer because I'm still alive and well," she said.
I learnt later that Yvonne was first diagnosed with ductal carcinoma in-situ (DCIS) after a needle biopsy of two breast lumps detected on a health screening ultrasound.
She underwent surgery to remove the lumps but the DCIS turned out to be more extensive, covering more than 7cm in her breast. It was not possible to clear all the cancer, so her surgeon tried to persuade her to have the affected breast removed.
"I have been taking organic food and Chinese medicine these two years. Mastectomy can't be the only way," she reasoned.
I decided it might be wiser to battle this alongside her rather than to belittle her health strategy.
After some coaxing, she agreed to undergo a mammogram and an ultrasound scan. The tests showed ominous calcifications involving the entire breast.
I struck a bargain with her to undergo a repeat biopsy. If it showed cancer, this would indicate that her strategy was ineffective and she would need further surgery.
She agreed. The result was not too far from my expectations.
She was finally cleared of her cancer two years after diagnosis.
Although her entire breast was affected by DCIS, there was no invasive component. Hence, her chance of a cure was greater than 99 per cent through surgery alone.
She was given a second chance and I was so glad that she seized it.
Better late than never
Juliet (not her real name) was a 38-year-old air stewardess who experienced pain in her left breast.
Despite the dense breast tissue imaged on her mammogram, the 2cm area of abnormality was unmistakable: chalk dust-sized calcium deposits of varying sizes lined up in a linear fashion in the outer aspect of her left breast, whose innocuity belies the sinister biological complexities beneath.
These calcifications had escaped detection by an ultrasound scan, and her breast felt normal. But a biopsy confirmed high-grade DCIS.
In denial, she said: "I'm too young to have cancer. I eat right, I exercise three times a week and my family history is clean. This can't be cancer."
I explained that DCIS is early stage cancer and surgical treatment can result in near 100 per cent cure rates.
I did not see Juliet again until almost a year later.
She had just gotten married and had come to see me because the pain in her breast had worsened.
I had a sinking feeling as I examined her breasts. A 3cm lump had surfaced.
"I'm eight weeks pregnant. I read that lumps could be due to pregnancy?" she ventured hopefully.
It took another biopsy to convince her of the diagnosis.
Unfortunately, the cancer was now invasive, having progressed from DCIS.
Juliet was eventually diagnosed with stage three breast cancer and had to undergo a mastectomy during her pregnancy.
Because four of her lymph nodes had cancer involvement, she also had to receive chemotherapy during her pregnancy.
Her baby was delivered at 32 weeks weighing just 1.8kg.
"I should have done the surgery a year ago," she said with a hint of regret.
I could not have agreed more.
Still, I was thankful that Juliet was given a second chance to live the new segment of her life as a wife and mother.
Early Warning Sign
DCIS constitutes 18 to 25 per cent of all breast cancer cases detected.
It has the potential to progress to invasive cancer over time.
At this stage, the cancerous cells remain confined within the breast ducts and have not broken through the ductal lining to invade the surrounding breast tissue and gain access to the circulatory system.
Another mutation is required before it becomes invasive cancer.
DCIS is the stage where timely surgical intervention can clear a patient of cancer. Conversely, this is also the stage where progression to invasive disease is possible if the condition is left untreated.
Not all kinds of DCIS are alike. The more aggressive form progresses to invasive disease, while the more quiescent form may remain dormant for decades.
However, too little is known about the disease to be certain which cases of DCIS will progress to invasive breast cancer and which will not, as well as the specific timeframes applicable in each case.
So, currently, all DCIS cases are treated to prevent them from progressing to invasive breast cancer.
We do know that once cancerous cells have gained access to the circulatory system, one can no longer speak of a confident cure.
Treatment such as chemotherapy or anti-hormone therapy is often needed to avoid a relapse in the future.
This is the reason why so much emphasis is placed on detecting breast cancer in the pre-invasive stage through screening.
In 90 per cent of cases, DCIS has no symptoms but shows up as microcalcifications that can be detected by mammograms.
One may argue that there is an over-treatment of DCIS, given that some cases may never progress to invasive cancer.
But progression to invasive cancer is not completely understood and cannot be reliably predicted.
Until such a time when accurate prediction is possible, it is, on balance, far better to err on the side of caution by treating DCIS early.
DCIS is cancer which gives women a chance before rearing its ugly head.
Dr Esther Chuwa is a consultant breast surgeon at Gleneagles Hospital. Having practised as a surgical fellow at Nottingham Breast Institute in Britain, she sub-specialises in oncoplastic breast surgery - the use of plastic surgery techniques in excising breast cancer.
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