Dr. Iqbal on HER2-Driven Gastric Cancer

Syma Iqbal, MD, an associate professor of clinical medicine at the Keck School of Medicine, University of Southern California, discusses the need to discover more reliable biomarkers in gastric cancer.

To date, the only consistent biomarker for gastric cancer has been HER2, Iqbal says. Patients with HER2-positive disease benefit from HER2 suppression in the frontline setting with targeted agents such as trastuzumab (Herceptin). Other than HER2, the only other biomarker that has shown potential in gastric cancer has been PD-L1, which is thought to be predictive of immunotherapy response.

PD-L1 expression has been particularly effective in other diseases like lung cancer and melanoma, but there are still unanswered questions regarding its use in gastric cancer. Therefore, Iqbal says she is unsure if she’s ready to consider PD-L1 as a biomarker in routine clinical practice.

Iqbal adds that even the HER2 story has had its caveats in this space. While targeted therapy works in the frontline setting, it has yet to show any benefit for second-line treatment.