Time now for the "Heat index" and this morning's hot button. A new report raising big questions about breast cancer treatment. As many as 60,000 women a year are diagnosed with something known as stage zero breast cancer and now a new study raising doubts about the effectiveness of early intervention. This morning a new study shedding light on dcis, also known as stage zero breast cancer. As many as 60,000 women each year are told they have these precancerous cells and until now urged to undergo aggressive treatments like a mastectomy and radiation to prevent cancer. It is a condition that puts you at higher risk to develop an invasive cancer. Reporter: The study that followed 100,000 women for 20 years shows these painful and risky procedures may be unnecessary. The "Journal of the medical association oncology report" found only 3.3% of these women die from breast cancer. It is not a lethal condition. You won't die from it. So it's important to know you don't have to do more than you need. Reporter: But the study did find that some african-american women with dcis are still at a higher risk. And joining us now from los Angeles is Dr. Jennifer Ashton. Jen, thanks for being with us. Good morning, Amy. So help us further explain this stage zero cancer. Is it technically cancer? Well, first you have to understand the range of pathology results for this type of breast cancer and it's really a spectrum that goes from Normal through a couple of stages to atypical cells to dcis to invasive ductal breast cancer and the key here and the controversy really is in those middle stages, the atypical cell, the dcis and how best to treat them or should they be treated at all? That's where the controversy is. Right, so if the recommendation is to do nothing that emotionally has to be frightening to hear as a patient? Oh, it's not only frightening, this concept of watchful waiting is challenging for the medical community, for doctors and for patients alike. We're already seeing that occur in other types of cancers, for example, in cervical cancer, today we're watching and following certain types of abnormal pap smears where ten years ago those women would have had surgery on their cervix so this is the concept. Should this type of lesion be treated and if so, in what type of patient? And, Jen, it's not just about whether or not dcis should be treated. There is is also disagreement among pathologists about how it's diagnosed, correct? Absolutely and, listen, we have to remember what the pathologists do when they look at the slide, this is an art and science. There is a human component, there is a surgical component in terms of margins and can be very, very subtle differences between atypical cells and dcis in some case. So, Jen, if you're someone who has been told they have dcis or stage zero breast cancer, what is your recommendation as a doctor? Well, I get this question all the time, Amy, from women so the first thing I recommend is stop, take a minute, take a deep breath. This feels like an emergency, and emotionally it really does feel that way but medically you have time. The second thing, if possible, consider asking for those biopsy slides and bringing them to another pathologist for a second opinion. That could be at the same hospital or at a completely different breast center and, lastly, you have to weigh the risks versus the benefits, versus the options and that's the risk of treating versus the risk of not treating versus the benefiting of treating or benefit of not treating and those options. This is not one size fits so so we'll be following this closely in the future and hearing a lot more about had. Every cancer is different, Dr. Jen Ashton, thank you very much for being with us. You bet, Amy.
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