What Did the Research Discover?
Gastric and gastroesophageal junction (G/GEJ) cancers are among the deadliest cancers, and while immunotherapy has become a standard treatment for advanced cases, its role in earlier-stage disease is not well understood. The PANDA trial investigated whether neoadjuvant (before surgery) immunotherapy combined with chemotherapy could improve outcomes in patients with nonmetastatic, resectable G/GEJ cancer.
In this study, 21 patients were treated with one cycle of atezolizumab (an anti-PD-L1 immunotherapy) alone, followed by four cycles of atezolizumab combined with chemotherapy (docetaxel, oxaliplatin, and capecitabine). The main goal was to assess whether the treatment was safe and effective in reducing the tumor before surgery.
Results showed that treatment was well tolerated, with no life-threatening side effects. Importantly, 70% of patients had a major pathologic response (MPR), meaning their tumors shrank significantly, with 45% achieving a complete response (pCR), where no viable cancer cells remained. At a 47-month median follow-up, nearly all responders were alive and disease-free, while most nonresponders had experienced cancer recurrence.
Further analysis found that patients whose tumors had a higher number of CD8+ T cells expressing PD-1 before treatment were more likely to respond. Additionally, administering atezolizumab before chemotherapy appeared to increase immune activation in the tumor environment.
How Can I Apply This Information?
These findings suggest that giving anti-PD-L1 immunotherapy before chemotherapy may help prime the immune system to fight G/GEJ cancer more effectively. If validated in larger studies, this approach could become a new standard for neoadjuvant treatment in nonmetastatic gastric and gastroesophageal junction cancers.
For patients diagnosed with resectable G/GEJ cancer, this study highlights the potential benefits of immunotherapy as part of pre-surgical treatment. Patients may want to discuss clinical trial options with their oncologists, particularly those involving immunotherapy before surgery.
Source:
Verschoor YL, van de Haar J, van den Berg JG, van Sandick JW, Kodach LL, van Dieren JM, Balduzzi S, Grootscholten C, IJsselsteijn ME, Veenhof AA, Hartemink KJ. Neoadjuvant atezolizumab plus chemotherapy in gastric and gastroesophageal junction adenocarcinoma: the phase 2 PANDA trial. Nature medicine. 2024 Feb;30(2):519-30. https://pubmed.ncbi.nlm.nih.gov/38191613/
