With Immunotherapy, One in Every 4 Lung Cancer Patients Survived More Than 5 Years

Approximately a quarter of previously untreated patients with non-small cell lung cancer (NSCLC) treated with pembrolizumab (Keytruda) immunotherapy survive at least 5 years, and the rate is higher for patients with PD-L1-positive tumors. Before immunotherapies began to be used for advanced lung cancer, the 5-year survival rate was only around 5%.

These results, presented at the American Society of Clinical Oncology (ASCO) 2019 Congress, came from long-term efficacy and safety follow-up of pembrolizumabin advanced non-small cell lung cancer (NSCLC), in the KEYNOTE- 001 named clinical trial.

Until the last 1-2 years, metastatic (stage 4) NSCLC required us to paint a rather bleak picture when seeing a patient: the chance of surviving 5 years would be 5%, sometimes even less.

Now, according to these data, 1 in every 4 patients with advanced NSCLC treated with pembrolizumab will live at least 5 years, changing our perspective on lung cancer.

Summary of the KEYNOTE- 001 Study

• The study initially included patients without EGFR or ALK gene mutations : there were 550 patients, more than 100 of whom had received no previous treatment at study entry.
• At ASCO 2019, data were presented on 100 patients still alive after a median follow-up of 60 months. These patients had received pembrolizumab for at least 2 years.
• At the end of year 5, 23% of treatment-naive (previously untreated) patients and 16% of previously treated patients were still alive.
• Among patients with PD-L1 positivity of at least 50%, these rates rose to 30% for treatment-naive patients and 25% for previously treated patients. 
• For previously treated patients with PD-L1 positivity between 1% and 49%, 5-year survival was 13%, while it was 16% in treatment-naive patients.
• Specifically among patients able to receive pembrolizumab for at least 2 years, 5-year overall survival was 78.6% in treatment-naive patients and 75.8% in previously treated patients.
• Immunotherapy-related side effects were reported in 92 patients (17%); hypothyroidism was the most common (9%). The most serious side effect was pneumonitis, but it occurred in fewer than 5% of patients.
• Regarding side effects, pembrolizumab caused no unexpected "long-term" adverse effects.

- Related Topic: What Are the Side Effects of Immunotherapy Drugs and How Are They Treated?

Commentary

We are witnessing immunotherapies significantly change the course of more than 10 major cancer types, including lung cancer, within 5 years. Response rates in patients with non-small cell lung cancer treated with pembrolizumab for at least 2 years are remarkably high; however, complete responses are uncommon. The longer-term fate of metastases with a clear radiological response but without complete disappearance remains somewhat uncertain. Biopsies of these tumor formations reportedly show active cancer in some cases, while others show scar tissue or granuloma. This may be an interesting area for future research. We also need to await results of ongoing studies to clarify the most appropriate treatment for patients with PD-L1 positivity between 1% and 49%—whether it should be combined with chemotherapy.