In a nutshell
This study investigated the effectiveness and safety of atezolizumab (Tecentriq) as an addition to chemotherapy before surgery for patients with early-stage triple-negative breast cancer (TNBC).
The data showed that the combination is effective in improving treatment response in these patients.
Some background
After the initial diagnosis of breast cancer (BC), several tests are run to assess the specific type of BC. The results will determine the type of applied treatment. BC might grow in response to the female hormones estrogen or progesterone. Some types grow in response to the human epidermal growth factor receptor 2 (HER2). If a specific BC is not triggered by any of these factors, it is a TNBC.
Treatment for early-stage TNBC is commonly chemotherapy (CT) followed by surgery to remove the tumor. The aim of CT before surgery is to help achieve a pathological complete response (pCR). This means that no cancer can be found in tissue samples removed during surgery after CT.
Atezolizumab is an immunotherapy that supports the body to strengthen its response in the process of fighting cancer during CT. Atezolizumab combined with CT has shown to improved the outcomes of patients with advanced TNBC. However, the effectiveness and safety of CT in combination with atezolizumab before surgery to remove tumors in early TNBC have not been investigated.
Methods & findings
This study included 333 women with early-stage TNBC who did not undergo any treatment prior to participating in the study. The patients were divided into two groups. Both groups received CT treatment for 20 weeks. This included nab-paclitaxel (Abraxane), followed by doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan). One group (165 patients) additionally received 840mg atezolizumab every two weeks. The second group (168 patients) received a placebo. All patients then underwent tumor removal surgery. The main measures recorded were pCR and side effects for an average follow-up time of 20.6 months (atezolizumab) and19.8 months (placebo).
Significantly more patients in the atezolizumab group (58%) and than the placebo group (41%) achieved a pCR. In patients with PD-L1 positive tumors, a pCR was achieved in 69% of the atezolizumab group and 49% of the placebo group. PD-L1 is a protein found on some cancer cells (PD-L1 positive tumors) that is targeted by atezolizumab.
Medium-severe side effects were recorded in 63% of atezolizumab-treated patients compared to 60% in the placebo-treated patients. The most common side effects were low white blood cell counts, increased liver enzymes, and pneumonia. Severe side effects were recorded in 30% of the atezolizumab group compared to 18% in the placebo group.
The bottom line
The authors recommend atezolizumab as an effective treatment in combination with chemotherapy with acceptable side effects before surgery in patients with early TNBC.
The fine print
This study was funded by F Hoffmann-La Roche, the pharmaceutical company producing atezolizumab.
Published By :
Lancet (London, England)
Date :
Sep 18, 2020
