In brief
- An international cohort study identified 77 patients from 18 centres in six countries who were diagnosed with non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC) after allogeneic hematopoietic cell transplantation (HCT).
- In advanced NSCLC, median overall survival was 17.4 months with immune checkpoint inhibitor (ICI)-based therapy (n=20) and 4.7 months with chemotherapy alone (n=16), a hazard ratio of 0.32.
- Grade 3–5 immune-related adverse events (irAEs) or graft-versus-host disease (GvHD) occurred in 2 of 30 ICI-containing lines of therapy (7%) and in 1 of 47 lines without an ICI (2%).
- Patients who received ICIs began treatment a median of 7.1 years after transplantation, against 3.0 years for those who did not, and none of them required treatment for GvHD.
- Treatment was not randomised, and the authors limit their conclusion to selected patients with presumed host immune tolerance.
Study at a glance
- Cohort: 77 patients from 18 centres in six countries
- Population: NSCLC or SCLC diagnosed after allogeneic HCT; median 4.2 years from transplant to diagnosis
- Patients: 64% male; 81% current or former smokers
- Comparison: ICI-based therapy (n=20) vs chemotherapy alone (n=16) in advanced NSCLC
- Survival: median overall survival 17.4 vs 4.7 months; HR 0.32 (95% CI 0.13–0.77)
- Safety: grade 3–5 irAEs or GvHD in 2 of 30 ICI-containing lines (7%) and 1 of 47 other lines (2%)
- Not reported: in the abstract, progression-free survival, response rates and survival outcomes for the patients with SCLC
A cohort gathered across 18 centres in six countries
The investigators identified 77 people with a history of allogeneic HCT who were later diagnosed with NSCLC or SCLC, and lung cancer was diagnosed a median of 4.2 years after the transplant. Of these patients, 64% were male and 81% were current or former smokers.
The authors start from the improvement in long-term outcomes after allogeneic HCT, which makes second cancers, lung cancer among them, more relevant in transplant survivors. For these patients the clinical utility of ICIs has been unclear, and concerns about GvHD have persisted. The study evaluated clinical characteristics, survival and toxicity in this group.
A median overall survival of 17.4 months with checkpoint inhibitors against 4.7 months with chemotherapy
Among patients with advanced NSCLC, the 20 who received ICI-based therapy had a hazard ratio for death of 0.32 (95% CI 0.13–0.77) when compared with the 16 who were treated with chemotherapy alone.
The comparison rests on 36 patients, and treatment in this cohort was not assigned at random. The confidence interval is wide, running from a 23% to an 87% reduction in the hazard of death. The abstract reports the association; it does not describe an adjustment for the differences between the two groups.
Severe immune toxicity or GvHD in 2 of 30 checkpoint inhibitor lines
Across 77 lines of systemic therapy given to 54 patients, grade 3–5 irAEs or GvHD occurred in 7% of the ICI-containing lines and in 2% of the lines without an ICI.
The authors report that they did not observe a clear signal of excess irAEs or GvHD. The counts are small, with three events in total across both groups, so the study can describe the toxicity seen but cannot estimate the difference between the groups with any precision.
Patients given checkpoint inhibitors were further from their transplant
The median interval from HCT to the start of treatment was 7.1 years in patients who received an ICI and 3.0 years in those who did not. No patient in the ICI group required treatment for GvHD, compared with 25% of the patients who were treated without an ICI.
The authors interpret these differences as an indication of improved host immune tolerance in the patients who were given ICIs. The patients selected for checkpoint blockade therefore differed from the comparison group before treatment began, and the survival comparison carries that difference with it.
“In our study, ICI-based therapies were associated with prolonged survival in selected patients with advanced NSCLC and presumed host immune tolerance.”Rost et al., Lung Cancer (2026)
The authors support considering ICIs in transplant survivors with lung cancer
On the basis of these results, the authors conclude that their results support considering the use of ICIs in this population. Their conclusion is restricted to selected patients, and the comparison behind it is observational and small, with fewer than 40 patients with advanced NSCLC in the survival analysis.
Sources
- Lung Cancer. Lung cancer after allogeneic hematopoietic stem cell transplantation (2026-09-01). doi.org
Featuring Lung Summit faculty
This study was co-authored by Lung Summit faculty Nikolaj Frost, Martin Reck and Alessio Cortellini.
This article was produced independently by the Lung Summit editorial team, without industry funding or input.
