Herceptin May Be of Little Use in Immune Cell-Heavy Breast Ca

The gist: Many women with HER2-positive breast cancer take the drug trastuzumab (aka Herceptin) along with chemotherapy after tumor-removal surgery to keep the cancer from returning. However, new research shows that women who have high levels of certain immune system cells in their tumors might not benefit from Herceptin. For these patients, chemotherapy might be just as effective at preventing the return of cancer as the chemo/Herceptin combo.

“HER2-positive breast cancers with a high level of immune cell infiltration might not benefit from the addition of trastuzumab (Herceptin) to chemotherapy, a trial analysis suggested.

“The 10% of patients with stromal tumor-infiltrating lymphocyte-predominant breast cancer in the Alliance N9831 trial showed similar recurrence-free survival (RFS) whether they received chemotherapy alone or with trastuzumab (10-year rate 90.9% versus 80.0%,P=0.21), Edith A. Perez, MD, of the Mayo Clinic in Jacksonville, Fla., and colleagues found.

“The rest showed, as expected, significantly better recurrence-free survival with addition of trastuzumab (10-year rate 79.6% versus 64.3%, hazard ratio 0.49, P=0.0003), they reported here at the San Antonio Breast Cancer Symposium.”