Treatment Not Needed for Breast Cancer Type

Chemotherapy Not an Indication of Prognosis

Debra Wiggins' chemotherapy treatment did little to shrink her breast cancer tumor before surgery, but that has not prevented her recovery from the disease. The Houston mother of three is doing fine more than two years after surgery and radiation.

Study results now have found that women with Debra's type of breast cancer invasive lobular carcinoma do not respond to chemotherapy before surgery and, therefore, do not need chemotherapy.

"We were very surprised to find that chemotherapy treatment is not necessary to ensuring a good prognosis in these women," says the study's lead author, Massimo Cristofanilli, M.D., an associate professor in the Department of Breast Medical Oncology at M. D. Anderson. "And if it does not bring long-term benefit to patients, the use of preoperative chemotherapy in advanced lobular carcinoma should not be encouraged unless indicated by the fact that they are inoperable."

Two forms of cancer compared

The study, which was published in the January issue of the Journal of Clinical Oncology, involved a review of six different clinical trials of 912 women with invasive lobular carcinoma and 122 with invasive ductal carcinoma.

Invasive ductal carcinoma, the most common form, develops in the milk duct vessels that extend from the lobules to the nipple.

Invasive lobular carcinoma, which accounts for 5% to 15% of breast cancer, develops in the lobules of the breast, the glands that make breast milk.

Both forms are treated with neoadjuvant chemotherapy (chemotherapy before surgery) to reduce the size of the tumor so that surgery can be minimized. It also allows physicians to determine if the patient responds to the particular chemotherapy drug, in the event that it might be needed in follow-up care after surgery.

Patients need tailored treatment

But now, after reviewing the results, Cristofanilli found that patients with invasive lobular carcinoma who were not helped by chemotherapy had a better long-term outcome than women with invasive ductal carcinoma who had a seemingly good response to chemotherapy.

"We always have thought that a poor response to chemotherapy indicated a worse prognosis, but this study shows that is not true," he says. "In fact, these results suggest women with invasive lobular carcinoma have a different kind of disease, and may benefit from a treatment that is more adequately tailored to the biology of their cancer."

In early 2002, Wiggins realized there might be more than one type of breast cancer when she felt something odd on her right breast. It wasn't a lump, but a thickness that felt like "a piece of Jello," she says. She was referred to M. D. Anderson and was treated with chemotherapy, but "I don't think there was any change," she recalls. Her cancer had spread throughout her breast and in the lymph nodes on both sides.

Chemotherapy not found to be helpful

Wiggins had a mastectomy to remove the cancer. Surgeons also reduced the size of her left breast, but on examination, they discovered early signs of cancer in that breast as well, further evidence that neoadjuvant chemotherapy had little effect. That breast was also removed.

"Mrs. Wiggins is an example of how lobular carcinoma will not respond to neoadjuvant chemotherapy but still will not affect what appears to be a quite promising outcome," says Cristofanilli, who is her oncologist.

Wiggins currently is taking the drug Arimidex, a hormonal therapy that may prove to be the best post-surgical way to treat this form of cancer, especially in women whose cancer is estrogen-receptor positive, he says. Arimidex is an "aromatase inhibitor" drug that stops production of the estrogen that can act to fuel breast cancer's growth.

"Before this study, I don't think anyone realized the disease should be treated differently," Cristofanilli says. "Now we need to think about revising our clinical approach and, more importantly, the way we communicate prognoses to women with lobular cancer that have shown poor response to chemotherapy."