Prophylactic cranial irradiation in extensive disease small cell lung cancer: An endless debate

Abstract

Extensive disease Small cell lung cancer (ED-SCLC) represents a very aggressive malignancy in which brain metastases (BM) are quite common. Clinical trials on prophylactic cranial irradiation (PCI) have showed a clear decrease in the risk of developing BM but conflicting results concerning a possible survival advantage. A landmark European Organisation for Research and Treatment of Cancer (EORTC) prospective trial, as well as multitude of retrospective series confirm survival benefit after PCI. Recently, a Japan Clinical Oncology Group (JCOG) study did not find such survival benefit, provided that non-irradiated patients are closely followed by MRI. Henceforth, the role of PCI in this population has been questioned, on the ground of the possible absence of survival benefit, leading to a gradual shift in oncology practice. We performed a review of the literature on the subject of PCI in ED-SCLC patients. We conclude that PCI could still play a crucial role in these patients, considering not only a possible survival benefit, but also alternative endpoints, such as improved local control, delay in the onset of symptomatic BM and lower toxicity of a prophylactic- rather than an eventual active-intent treatment. Individualized attitude should be discussed with patients, while addressing all arguments in favour and against PCI.

Keywords: Brain metastases; ED-SCLC; Extensive; PCI; Prophylactic cranial irradiation; Small cell lung cancer.