CLASSIC
After curative D2 gastrectomy for stage II–IIIB gastric cancer, does adjuvant capecitabine–oxaliplatin improve outcomes versus surgery alone?
Trial design and population
Key results
At 5 years, DFS was 68% with adjuvant CAPOX vs 53% with surgery alone (HR 0.58, 95% CI 0.47–0.72). Five-year OS was approximately 78% vs 69% (HR 0.66, 95% CI 0.51–0.85).
Source-reported outcome visualization
5-year disease-free survival · 5 years
Bars are scaled to the larger reported group value; endpoint, unit and horizon are labelled. Values are source-reported, not estimated from medians.
Absolute Effect
Absolute 5-year DFS gain 15 percentage points; NNT 7 based on 5-year DFS. Approximate 5-year OS gain 9 points; NNT 12 based on 5-year OS.
NNT: 7 (5-year DFS); ≈12 (5-year OS). Use only at the stated endpoint/time horizon; median survival differences are not converted into NNT.
NNH: Not quantifiable. Grade 3–4 adverse events occurred in approximately 56% with CAPOX. Hand-foot syndrome, nausea, neutropenia and oxaliplatin neuropathy are important; NNH not calculated without a comparator-matched fixed-time harm endpoint.
Time-to-event hazard ratios and median survival are not treated as absolute risk differences. Where no defensible fixed-time NNT/NNH is available, the source-reported endpoint is visualized instead.
Safety and treatment burden
Grade 3–4 adverse events occurred in approximately 56% with CAPOX. Hand-foot syndrome, nausea, neutropenia and oxaliplatin neuropathy are important; NNH not calculated without a comparator-matched fixed-time harm endpoint.
Follow-up, maturity and limitations
Follow-up: Five-year follow-up analysis.
Conducted in East Asian centres with D2 surgery; does not directly compare postoperative CAPOX with perioperative chemotherapy used in many Western settings.
Clinical interpretation
Current-practice context · reviewed 20 October 2026
This page separates the original trial findings from contemporary treatment sequencing. Confirm current guidelines, local regulatory status, biomarker requirements, prior treatment exposure and patient-specific contraindications before applying the evidence. Historical comparators may no longer represent the current standard; subgroup findings and immature endpoints are labelled rather than generalized.