Objective:

To compare postoperative morbidity between patients receiving neoadjuvant immunotherapy plus chemotherapy (NICT) and those receiving neoadjuvant chemotherapy (NCT) alone for gastroesophageal junction adenocarcinoma.

Approach:

• Study Design: Single-center, retrospective cohort study including patients with locally advanced GEJ adenocarcinoma undergoing curative resection after NICT or NCT.
• Participants: 140 patients received NICT and 260 received NCT, with propensity score matching yielding 120 matched pairs.
• Outcomes: Primary outcome was major complications (Clavien-Dindo ≥III); secondary outcomes included specific surgical complications, immune-related adverse events (irAEs), and interval to surgery.

Key Findings:

• NICT was associated with improved major pathological regression (58.3% vs. 45.8%; p=0.028).
• No significant difference in major postoperative morbidity between NICT and NCT cohorts (25.8% vs. 22.5%; p=0.538).
• Specific technical complications such as anastomotic leak (11.7% vs. 10.0%) and conduit failure (3.3% vs. 2.5%) showed no significant differences.
• irAEs occurred in 13.3% of the NICT cohort without delaying surgical intervention.
• NICT was not an independent predictor of morbidity.

Interpretation:

The addition of immunotherapy to neoadjuvant chemotherapy for GEJ adenocarcinoma does not significantly increase the risk of major postoperative morbidity.

Limitations:

• Single-center study may limit generalizability.
• Retrospective design may introduce selection bias.

Conclusion:

These findings indicate that NICT does not significantly increase the risk of major postoperative morbidity in GEJ adenocarcinoma.