Immunotherapy Yields Long Survival in Gastric Cancer
Extended follow-up of a French phase II trial reports sustained four-year survival in a small group of patients with localized dMMR/MSI-H gastric or gastroesophageal junction adenocarcinoma.
Updated on Nov. 9, 2026 in Cancer
Neoadjuvant nivolumab plus ipilimumab, followed by adjuvant nivolumab, was associated with sustained long-term survival in localized dMMR/MSI-H gastric or gastroesophageal junction adenocarcinoma. The findings come from extended follow-up of the NEONIPIGA phase II trial, published in JAMA Oncology.
Why it matters
Gastric and gastroesophageal junction cancers with mismatch repair deficiency or microsatellite instability-high status represent a defined molecular subgroup, and the results add long-term outcome data for a combined immunotherapy approach in that population. The trial's nonrandomized design and small size limit how broadly the results can be applied.
The trial enrolled 32 patients with a median age of 65 years, and 72% were male, with a median follow-up of 48.3 months. Six deaths were reported, and 84% of patients completed neoadjuvant therapy while 44% completed all planned treatment.
The players
NEONIPIGA trial
A French, multicenter, nonrandomized phase II trial evaluating neoadjuvant and adjuvant immunotherapy in localized dMMR/MSI-H gastric or gastroesophageal junction adenocarcinoma.
JAMA Oncology
A peer-reviewed oncology journal published by the American Medical Association that carried the extended follow-up report.
The details
Patients received six cycles of neoadjuvant nivolumab plus two cycles of ipilimumab, followed by surgery and nine cycles of adjuvant nivolumab. One enrolled patient with metastatic disease was inadvertently included, and the authors state that further randomized studies are warranted.
Timeline
Median follow-up of the trial was 48.3 months.
Extended follow-up findings were published in JAMA Oncology on November 9, 2026.
Health Landscape
The extended NEONIPIGA follow-up updates the earlier report from the same French phase II trial with longer survival figures for dMMR/MSI-H gastric and gastroesophageal junction adenocarcinoma. It adds to a limited set of long-term outcome data for combined checkpoint immunotherapy in a molecularly defined subgroup.
Results from a small nonrandomized trial do not yet change standard treatment for gastric cancer. Patients and clinicians may watch for randomized studies that would clarify which patients are most likely to benefit from this approach.
The takeaway
Long-term survival in this small trial is encouraging for a defined molecular subgroup, but the authors call for randomized studies before the approach can be generalized. Readers should treat the findings as early evidence rather than a new standard of care.
Further reading
Explore more on Cancer research and treatment developments.
Source note: This article includes information reported by Ascopost.
