Dr. Voorwerk on Outcomes with Atezolizumab Plus Carboplatin in Metastatic Lobular Breast Cancer

Leonie Voorwerk, a PhD student at the Netherlands Cancer Institute, discusses outcomes with the combination of atezolizumab (Tecentriq) plus carboplatin in metastatic lobular breast cancer, which was evaluated as part of the phase 2 GELATO trial (NCT03147040).

In total, 22 patients received at least 1 cycle of atezolizumab and were available for further analysis, 5 of whom had triple-negative breast cancer (TNBC), according to Voorwerk. Among the 21 patients who were eligible for response evaluation, 4 patients experienced a partial response (PR), while 2 patients achieved stable disease for at least 6 months. This translated to an objective response rate of 19%, and a clinical benefit rate of 29%.

Additionally, investigators identified a median duration of response of 12 weeks, with 1 patient experiencing an ongoing response, Voorwerk says. At least 3 patients remained progression free at 6 months, meeting the primary end point of the trial. Among the 6 patients who experienced clinical benefit, defined as either PR or stable disease, 4 had TNBC.

Baseline stromal tumor-infiltrating lymphocytes and stromal CD8 counts were also investigated, Voorwerk adds. Although these factors were not associated with clinical benefit, a trend toward a higher PD-L1 expression was observed in patients who experienced clinical benefit with the regimen, Voorwerk concludes.