Breast cancer – most common cancer in women

MD Anderson Cancer Center
Date: 12/02/2013

 

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Lisa Garvin:  Welcome to Cancer Newsline, a podcast series from the University of Texas, MD Anderson Cancer Center. Cancer Newsline helps you stay current with the news on cancer research, diagnosis, treatment, and prevention, providing the latest information on reducing your family's cancer risk. I'm you host, Lisa Garvin. And today, our guest is Dr. Sharon Giordano, she is a professor of Breast Medical Oncology and also chair of Health Services Research Department here at MD Anderson. And our subject is breast cancer. Dr. Giordano, a very well known cancer, a fairly common cancer but I--we're kind of going to go through a primary here today. Let's talk about--there're basically two types, ignoring hormone receptors and so on and so forth of breast cancer. What are the two main types of breast cancer?

Dr. Sharon Giordano:  Well the two most common subtypes are either ductal breast cancer which makes up probably close to 80 percent and lobular breast cancer which is anywhere from 5 to 15 percent, and then of course there are some more rare subtypes but those are again less commonly seen.

Lisa Garvin:  And now, a ductal carcinoma happens in the milk ducts of the breast.

Dr. Sharon Giordano:  Right. And the lobular breast cancer arises from the terminal lobules of--essentially of the breast, so it has a lobular histology. It's more of a description when the pathologist looks at it under the microscope at different pattern.

Lisa Garvin:  Now, milk ducts are fairly close to the surface of the skin. Are they not in the breast or they kind of buried under fat and--

Dr. Sharon Giordano:  No, they can extend throughout the breast.

Lisa Garvin:  Does it--is it harder to find a lobular carcinoma on a mammogram that would be a ductal?

Dr. Sharon Giordano:   They are. They tend to be less distinct masses, so they are often harder to feel, harder to measure and they are sometimes more difficult to pick up on mammograms. For instance, sometimes if we have a new diagnosis of a patient with a lobular breast cancer, some of her surgeons will want to do an MRI to try to assess the extent of the disease if they think in that patient that they can't get an accurate picture with the mammogram.

Lisa Garvin:  You said that ductal is more common, correct?

Dr. Sharon Giordano:  Yes.

Lisa Garvin:  There's also what's called "in situ" which means localized I guess for a lack of a better term. Let's talk about disease in situ. What exactly does that mean?

Dr. Sharon Giordano:  So, we do say carcinoma in situ which is essentially a stage 0 breast cancer. If you think of 0 as a noninvasive breast cancer and then 1 to 4 as invasive breast cancers.

Dr. Sharon Giordano:   Within that in situ breast cancers, again, these two main subtypes, there's the ductal carcinoma in situ and lobular carcinoma in situ, and these two behave quite differently. When we think about ductal carcinoma in situ, many of these will progress on to become invasive breast cancer, so they're typically surgically excised, often treated with radiation and really need to be removed. Lobular carcinoma in situ is a little bit different because it's not thought to be a precursor to developing an invasive breast cancer. However, it does indicate that a patient has a higher risk of developing an invasive breast cancer but it might not be in the same breast that the lobular carcinoma is. It could even be in the other breast. So if a patient has lobular carcinoma in situ, again, they may be good candidates for preventative medications, so these would be things like their medications such as tamoxifen or raloxifene which can be used to help reduce the risk of a woman developing an invasive breast cancer.

Lisa Garvin:  And you said at this point, lobular carcinoma in situ progresses to be invasive about 10% of the time?

Dr. Sharon Giordano:  Probably not even that high. I think it would be lower than that, but it does--it can again be a risk factor for somebody developing breast cancer. So it increases the risk but it doesn't have such a high rate in itself of progressing.

Lisa Garvin:   How often do we catch any sort of breast cancer in situ? Is--I mean, usually diagnoses, are they more advanced or do you catch a lot of cases at stage 0?

Dr. Sharon Giordano:   It kind of depends on whether or not the patient's having screening. So for people that are undergoing regular screening mammography, we will often find cases that are stage 0 or noninvasive breast cancer. In contrast, almost by definition because if you can't feel it and there's no lump there, the only way you're going to pick it up is by screening. So if you're doing screening, we see a lot more of the noninvasive, if people are presenting with a lump, those are not always but usually invasive breast cancers.

Lisa Garvin:  Now, can you feel a lobular carcinoma like doing a breast self exam?

Dr. Sharon Giordano:   Yeah. As in most of the time, you can feel them but as opposed to ductal is almost always a solid mass, lobular sometimes it's a little bit softer, sometimes more indistinct margin, sometimes more difficult to feel. So it's not that you can't feel them, but they're not as distinct as ductal carcinomas.

Lisa Garvin:  So basically, the treatment for either ductal or lobular carcinoma--let's say pass the in situ stage, are the treatment regimens pretty much the same?

Dr. Sharon Giordano:  They are, yes. I mean, either--for patients with ductal and lobular really the basic standards of treatment be it surgery, chemotherapy, radiation, hormone therapy are the same. Often lobulars can be a little bit larger than ductals at diagnosis, probably because of that more patients with lobular end up needing to have a mastectomy, but either one can be options if the tumor is small.

Lisa Garvin:  Can you do a lumpectomy on either type of cancer?

Dr. Sharon Giordano:  Yes.

Lisa Garvin:  You can.

Dr. Sharon Giordano:  Yes.

Lisa Garvin:  OK.

Dr. Sharon Giordano:  Yes. Either kind of cancer patients are candidate for lumpectomy if the tumor is small enough relative to the size of the breast. So it's really only because the lobulars tend to be larger cancers that those patients more often would need a mastectomy. Lobular is also known for being almost always estrogen receptor-positive. So these patients often are really good candidates for anti-hormonal treatment as part of their breast cancer therapy.

Lisa Garvin:  Now, people who do have estrogen receptor-positive cancers, do they have to be on hormone therapy for the rest of their lifetime?

Dr. Sharon Giordano:  No, it's not typically a lifetime treatment. We do typically treat these patients though with drugs that block estrogen or the effects of estrogen for anywhere between 5 and 10 years. For many, many years, our standard has been five years of treatment, however, there are some recent data that's come out within the past year particularly for patients treated with tamoxifen that suggest that 10 years might even be better than five years. For the other class of anti-estrogens, the aromatase inhibitors which really work in postmenopausal women to block estrogen production, still five years is a standard for those medications. However, again, there are studies that are trying to evaluate whether 10 is better than five years and we're still waiting on those results. So, short answer, tamoxifen, the standard is switching to 10 years, aromatase inhibitor, it's still five, but neither one of them is for life.

Lisa Garvin:  Now, tamoxifen is a pretty big success story. I mean, it really kind of came on to the scene just within the last decade. How's the continued track record of tamoxifen?

Dr. Sharon Giordano:   Tamoxifen, it's been around for a while but it is a phenomenally effective drug, so it can reduce the risk of relapse by half. So it's--even though it's just a pill and it's quite easy to take when you compare it to other treatments like chemotherapy or, you know, even radiation therapy. It's an enormously effective drug and can be a really crucial part of a woman's treatment for breast cancer, or a man's.

Lisa Garvin:  As far as outcomes for breast cancer patients, have they improved much over the last 10 to 20 years?

Dr. Sharon Giordano:  They have. It's been really quite a success story. We have seen overtime a continuing decline in death rates for breast cancer. Probably, some of this is due to screening and picking up cancer earlier, but we also think some of this is due to improvements in treatment. If we look--specifically, if we look at the difference between ductal and lobular cancers, in general, the prognosis of these two types is similar. But if you look overtime, they have slightly different patterns. We often, with ductal, might see earlier recurrences which be less common with the lobular. However, lobular can tend to have later patterns of recurrence. We've also seen that for patients with lobular breast cancer when they do develop metastatic disease or if they do develop metastatic disease, the patterns are a little bit different. So we see more commonly see bone metastasis or metastasis to other organs like the GI tract or the ovaries which are kind of unusual for breast cancer.

Lisa Garvin:  As far as the hormonal aspect of cancer, I know there's been a lot of work on targeted therapies to target specific estrogen receptors, how was that going? Have we found new biomarkers? Are we continuing to improve the ones that we do know about?

Dr. Sharon Giordano:   Both. I mean, I think that estrogen receptor is probably the best biomarker that we have for breast cancer right now and as you mentioned, a lot of our treatments really are focused on that particular marker. So drugs like tamoxifen, drugs like aromatase inhibitors are really focused on the estrogen receptor of breast cancer. There's also been a drug, everolimus that had been approved for breast cancer within the past couple of years that can be given for women with metastatic breast cancer in combination with the hormone agents, and helps overcome resistance and is looking like it may lead to better long-term outcomes for those patients.

Lisa Garvin:  Now, screening, I think women get a mix bag on mammograms. One day we hear you should get it this many times and other day you say, you know, we shouldn't get it at all. What is the current thinking on screening?

Dr. Sharon Giordano:   Well, that is a controversial, controversial topic. I'd say that certainly, we do recommend annual mammography after age 50 and as long as a woman is in good health. There is a lot of controversy a couple of years ago when the--for women 40 to 50 years old, it was pointed out that that group may benefit less. I think that's still an area of a lot of controversy because certainly, those are young women with a lot of life at risk and we certainly want to detect breast cancer earlier in those patients. On the other hand, because younger women have denser breasts, mammography may not work as well on that population, and so that led to a lot of controversy in that area.

Lisa Garvin:  Are there efforts to bring down false positives in screenings? Because, you know, a lot of women will have just a benign hyperplasia and what? Have to get a biopsy because it looks suspicious or different. Is there a way to reduce false positives in mammogram screenings?

Dr. Sharon Giordano:   I mean, I think that there's constant work looking to improve the accuracy of screening mammography whether or not it's improved visualization techniques, higher quality mammograms, looking at mammogram in conjunction with ultrasound or looking at the role of MRI. There's certainly a lot of work being done to try to optimize screening techniques so that women don't have to undergo unnecessary biopsies.

Lisa Garvin:   And I know breast and ovarian cancer is one of MD Anderson's moon shots or it's a disease we were focusing a lot of effort in translational research and getting the research to the patients. Is there anything going on with breast for the Moon Shots Program?

Dr. Sharon Giordano:  Yeah, absolutely. And the Moon Shot Program has been focusing on triple-negative breast cancer which again is a very high risk subset of breast cancer that we can't treat with targeted therapy such as estrogen receptor or estrogen blockers or HER2-targeted therapy. So the Moon Shots, from the breast cancer perspective, are really focusing on this high risk tuple-negative breast cancer.

Lisa Garvin:  And about how many people are in that pool?

Dr. Sharon Giordano:  That's probably about 15 to 20 percent of breast cancer diagnosis.

Lisa Garvin:  But that typically happens in a younger population or is it kind of average?

Dr. Sharon Giordano:  No. People with triple-negative breast cancer deal on average tend to be younger.

Lisa Garvin:  Well, it sounds like we've got a fairly good handle on breast cancer. Overall, where do you hope to go in the next five years?

Dr. Sharon Giordano:   I mean, I think we have seen really substantial improvements in patient's outcome from breast cancer. But, you know, sometimes when you're in the clinic, you have to remember there are still many, many people that are affected with this disease and so, you know, I think that we still do have a long way to go to help both prevent the disease as well as to design more effective and less toxic treatments for patients that are diagnosed.

Lisa Garvin:   Great. Thank you very much.

Dr. Sharon Giordano:  Thank you.

Lisa Garvin:   If you have questions about anything you heard today on Cancer Newsline, contact askMDAnderson at 1-877-MDA-6789 [Background Music] or online at mdanderson.org/ask. Thank you for listening to this episode of Cancer Newsline. Tune in for the next podcast in our series.

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