A non-small cell lung cancer fragile elderly patient treated with immunotherapy and non-ablative radiation therapy: a case report of a winning combination

Background: Radiation therapy is used in the clinical scenario of oligo-metastatic lung cancer as a weapon to delay the subsequent line of systemic therapy, particularly in the case of oligo-progressive disease. In this setting, the integration of immunotherapy and radiotherapy plays an important role to achieve local control and improve progression-free survival (PFS). Case presentation: We reported the case of an elderly fragile patient affected by advanced non-small cell lung cancer treated with pembrolizumab as first systemic line and immuno-modulant radiation therapy at oligo-progression. More specifically, he underwent stereotactic body radiation therapy using non-ablative regimen (24 Gy in 3 fractions) achieving partial response with abscopal effect and without drug interruption. After one year, during immunotherapy mediastinal and parenchymal progression occurred and he received another radiation treatment using conventional non-ablative regimen (40 Gy in 20 fractions). Complete response was observed without severe side effects (his poor respiratory function did not change during both treatments). Conclusion: In this case report we showed that the association of immunotherapy and non-ablative radiation regimens may represent a safe and effective strategy to achieve complete response also in fragile patients, in whom the burden of side effects should be prioritized.