Oligoprogression Predicts Improved Survival After Chemoimmunotherapy in Relapsed Small Cell Lung Cancer

Clinical Summary:

• Design/Population: A retrospective study analyzed patients with small cell lung cancer who experienced disease progression after chemoimmunotherapy, categorizing progression patterns as either oligoprogression or non-oligoprogression.
• Key Outcomes: Oligoprogression was associated with significantly improved outcomes, reduced hospitalization and hospice transition, and greater likelihood of receiving subsequent therapy, while non-oligoprogression correlated with worse clinical outcomes and distinct epigenetic features.
• Clinical Relevance: Patterns of progression may serve as a meaningful prognostic tool and help identify high-risk patients who may benefit from earlier clinical trial enrollment and biomarker-driven strategies.

Results from a retrospective analysis demonstrated that patterns of post-chemoimmunotherapy progression were strongly associated with outcomes among patients with relapsed small cell lung cancer (SCLC). 

“Chemoimmunotherapy for [SCLC) is initially effective… however, relapse is common,” stated Paresh Kumar, MBBS, Indiana University School of Medicine, Indianapolis, Indiana, and coauthors. “Patterns of progression may serve to prognosticate outcomes and identify biomarkers for relapsed SCLC.”

In this study, researchers collected data from electronic medical records of patients with SCLC who experienced disease progression following treatment with chemoimmunotherapy. Patients were categorized as either having oligoprogression ( ≤5 lesions in ≤2 organs) or non-oligoprogression for comparison of clinical outcomes. Tissue biopsies obtained at diagnosis and liquid biopsies collected at progression were analyzed for biomarker evaluation.

Key end points included overall survival (OS), rate of post-progression survival, and progression-free survival (PFS) on subsequent therapies. Key secondary end points included hospitalization rate, 3-month transition to hospice rate, and rate of subsequent therapies. 

At analysis, median OS was 17.5 months in patients with oligoprogression and 8.6 months in patients without oligoprogression (P < .001). Median post-progression survival was 11.1 months and 2.3 months, respectively (P < .001). Median PFS on subsequent therapies was 4.6 months in patients with oligoprogression and 1.8 months in patients without oligoprogression (P <.01). 

Rate of hospitalizations was 29.8% in patients with oligoprogression and 66.7% in patients without oligoprogression (P < .001), and the 3-month hospice transition rate was 6.4% and 50%, respectively (P <.001). Subsequent therapies were received by 89.4% of patients with oligoprogression and 58.3% of patients without oligoprogression (P = .01). The chemotherapy-free interval was not associated with post-progression OS (hazard ratio [HR], 1.62; 95% confidence interval [CI], 0.82 to 3.18; P = .16).

Biomarker analysis identified hypermethylation at 8 CpG sites associated with HOXA5 correlated with non-oligoprogression and predicted inferior survival in an independent cohort (P = .02).

“[Disease progression] patterns are an excellent tool to identify patients with relapsed SCLC who are at high risk of mortality, hospitalization, clinical decline, and poor outcomes with subsequent therapies…[and] such patients should be prioritized for clinical trial enrollment,” concluded Dr Kumar et al. “Prospective validation for outcomes with chemoimmunotherapy by HOXA5 status is warranted.”

Source:

Kumar P, Slaven JE, Zhou T, et al. Prognostic significance and biomarker identification by progression patterns in patients with small cell lung cancer after immune checkpoint inhibitors. Clin Lung Cancer. Published online: April 2, 2026. doi:10.1016/j.cllc.2026.03.014