Unexpected Favorable Outcome to Sintilimab Plus Bevacizumab in an EGFR-mutated Non-small Cell Lung Cancer Patient: A Case Report

A 53-year-old man diagnosed with disease stage IIIB pulmonary adenocarcinoma underwent chemotherapy and radiotherapy in the first-line setting. After disease progression, he received targeted therapy because of subsequent detection of EGFR exon 19 del mutation. Following an increase in his adrenal metastases, a combination of immunotherapy and antiangiogenic therapy (sintilimab plus bevacizumab) was commenced. After one month, imaging showed that the adrenal metastases had shrunk and a progression-free survival (PFS) of 6.0 months was achieved. In this case, we showed that the PD1 inhibitor sintilimab plus bevacizumab was effective in a refactory advanced EGFR-mutant NSCLC with positive PD-L1 expression. KEY POINTS: Our case report provides clinical evidence of the durable response of a patient with advanced EGFR-mutant lung adenocarcinoma to a combination of immunotherapy and anti-angiogenic agent, sintilimab and bevacizumab, as subsequent-line therapy. Sintilimab and bevacizumab combination therapy was well-tolerated and effective, resulting in dramatic tumor reduction and improvement in clinical symptoms.