Pembrolizumab in advanced pretreated small cell lung cancer patients with PD-L1 expression: data from the KEYNOTE-028 trial: a reason for hope?

Small cell lung cancer (SCLC) is an aggressive subtype of lung cancer, representing around 15% of all lung cancer cases. SCLC is characterized by neuroendocrine pathological features, strong association with tobacco exposure, rapid widespread, high mutational rates and no oncogenic drivers (1).