That therapeutic plateau is precisely why a new retrospective real-world study from Shanghai Pulmonary Hospital, affiliated with Tongji University, has generated such excitement. Published in Holistic Integrative Oncology, the analysis compared two very different treatment philosophies in 115 patients with limited-stage small-cell lung cancer treated between December 2017 and December 2023. Thirty-three patients received neoadjuvant chemoimmunotherapy, cycles of chemotherapy paired with an immune checkpoint inhibitor given before surgery, while eighty-two patients received the conventional approach of radical chemoradiotherapy. The results were dramatic: median overall survival had not been reached in the surgery group at the time of analysis, compared with 27.13 months in the chemoradiotherapy group, corresponding to a hazard ratio of 0.161 with a ninety-five percent confidence interval of 0.039 to 0.665 and a p-value of 0.004. At twenty-four months, eighty-eight point eight percent of the neoadjuvant group were still alive, versus only fifty point four percent of those treated with chemoradiotherapy.

The scientific rationale for this approach builds on one of the most consequential shifts in modern oncology. Immune checkpoint inhibitors targeting the PD-1 and PD-L1 axis first transformed the treatment of advanced non-small-cell lung cancer, and were then successfully moved into the early-stage, curative-intent setting. The landmark CheckMate 816 trial demonstrated that adding nivolumab, an anti-PD-1 antibody, to neoadjuvant chemotherapy significantly improved event-free survival and complete pathologic response rates in patients with resectable stage IB to IIIA non-small-cell disease. A cascade of subsequent trials, including NADIM II, KEYNOTE-671, CheckMate 77T, AEGEAN and RATIONALE-315, cemented perioperative chemoimmunotherapy as the new standard for resectable non-small-cell lung cancer, a treatment paradigm often described as the sandwich model: several cycles of drugs before the operation, surgery in the middle, and further therapy afterward.

Small-cell lung cancer, meanwhile, had its own immunotherapy breakthrough, though in a different arena. Phase three trials including IMpower133 and CASPIAN showed that adding atezolizumab or durvalumab to platinum-etoposide chemotherapy significantly extended overall survival in extensive-stage disease, and agents such as adebrelimab, tislelizumab and serplulimab delivered similar benefits, prompting regulatory approval of these combinations as first-line therapy. More recently, the ADRIATIC trial demonstrated that adjuvant durvalumab after definitive concurrent chemoradiotherapy significantly prolonged both overall and progression-free survival in limited-stage patients. What had never been rigorously tested, however, was whether the neoadjuvant chemoimmunotherapy-plus-surgery strategy validated in non-small-cell disease could be exported to small-cell histology, because surgery itself has long been viewed with suspicion in this tumor type owing to its propensity for early recurrence and metastasis.

The Shanghai team set out to answer that question with a meticulously annotated retrospective cohort. Inclusion criteria required pathologically confirmed pure or combined small-cell lung cancer, limited-stage disease according to the American Joint Committee on Cancer eighth edition, and at least one cycle of neoadjuvant chemoimmunotherapy followed by surgery or radical chemoradiotherapy. Radiologic responses were graded using RECIST version 1.1, and pathologic responses were quantified by senior histopathologists who measured the percentage of viable tumor cells remaining in resected specimens, following the International Association for the Study of Lung Cancer’s recommended framework: complete pathologic response means zero residual viable cells, major pathologic response means ten percent or fewer, and non-major response means more than ten percent. To guard against confounding between the two treatment groups, the investigators employed propensity score matching with one-to-two nearest-neighbor matching and a caliper width of 0.25, balancing covariates such as sex, age, smoking history, histology, clinical T and N stage, and radiographic response.

The pathologic outcomes in the neoadjuvant group were remarkable by any measure. Of the thirty-three patients who underwent surgery, eight, or 24.24 percent, achieved a complete pathologic response, and an additional ten patients, or 30.30 percent, achieved a major pathologic response, meaning that more than half of the treated tumors were rendered essentially invisible or nearly invisible to the pathologist. Radiologically, the objective response rate reached 90.91 percent, with nine patients achieving a complete response, twenty-one a partial response, and only two with stable disease. Every patient underwent lobectomy, the vast majority via video-assisted thoracoscopic surgery, and surgical margins were one hundred percent negative. The R0 resection rate, indicating complete microscopic removal of all disease, was 75.76 percent, with inadequate lymph node clearance the main reason for falling short of that benchmark. Pathologic downstaging relative to preoperative clinical staging occurred in 87.88 percent of patients, evidence that the preoperative drugs were genuinely shrinking and eradicating disease within the chest.

Survival statistics reinforced the enthusiasm. With a median follow-up of roughly 20.4 months for the neoadjuvant cohort and 45.4 months for the chemoradiotherapy cohort, event-free survival at twelve months stood at 93.30 percent in the surgical group, falling to 62.70 percent at twenty-four months. Overall survival was one hundred percent at one year. When the investigators applied propensity score matching to correct for baseline imbalances in staging and radiologic response, the survival advantage persisted: median overall survival remained unreached in the neoadjuvant group versus 23.20 months for chemoradiotherapy, with a hazard ratio of 0.112 and a p-value of 0.010. Subgroup analyses showed the overall survival benefit of neoadjuvant chemoimmunotherapy plus surgery was consistent across clinicopathologic strata, and multivariate Cox regression confirmed the treatment strategy as an independent prognostic factor for prolonged survival.

Several nuances emerged that will shape how clinicians select patients and sequence therapy. Patients whose scans showed a complete radiologic response tended to experience longer event-free and overall survival than those with only a partial response, and those achieving a complete or major pathologic response likewise fared better, mirroring the established relationship between pathologic response and survival surrogacy in non-small-cell lung cancer. The correlation between radiologic shrinkage and pathologic regression was positive, with a Pearson coefficient of 0.346, though the p-value of 0.053 narrowly missed conventional significance, likely a casualty of the small sample size. Interestingly, event-free survival appeared similar between patients who did and did not receive postoperative immunotherapy maintenance, raising the provocative hypothesis that a year of maintenance therapy, now routine in non-small-cell disease, may not be necessary in small-cell histology, a question the authors themselves flag for prospective validation. Patients with combined small-cell histology appeared to derive particular benefit, suggesting a subgroup deserving priority for this approach.

Safety data were reassuring within the limits of a retrospective design. All thirty-three neoadjuvant patients experienced at least a grade one or two treatment-related adverse event, with anemia, elevated liver enzymes, leukopenia and neutropenia the most common mild effects. Grade three or four events occurred in 45.45 percent of patients, a figure squarely within the forty to eighty-five percent range reported in phase three trials of chemoimmunotherapy in extensive-stage disease, and the dominant severe toxicity was neutrophil depletion, affecting twelve point twelve percent at grade three and 18.18 percent at grade four. Immune-mediated events were limited to mild pruritus and rash, two cases of grade two hypothyroidism, one case of grade three immune-related hepatitis and one of grade three polyneuropathy. Critically, no checkpoint-inhibitor pneumonitis, no treatment-related deaths, and no perioperative deaths or surgery-related adverse events were reported, undercutting the long-standing fear that operating on irradiated or immunologically activated small-cell tumors carries unacceptable risk.

The caveats deserve equal billing with the headlines. The neoadjuvant group contained only thirty-three patients and accrued far less follow-up time than the chemoradiotherapy cohort, so the uncrossed survival curves rest on a comparatively short observation window. PD-L1 expression, an important predictor of pathologic response in non-small-cell lung cancer, was not tested and therefore could not be correlated with efficacy. And as a single-center retrospective analysis, the study cannot escape the biases inherent to its design, however carefully propensity matching was applied. Even so, the consistency of the pathologic, radiologic and survival signals, combined with the absence of surgical mortality, makes a compelling case that for carefully selected patients with limited-stage small-cell lung cancer, neoadjuvant chemoimmunotherapy followed by surgery is no longer a fringe experiment but a candidate standard of care awaiting confirmation in large, prospective, randomized trials.

Subject of Research: Neoadjuvant chemoimmunotherapy followed by surgery for limited-stage small-cell lung cancer

Article Title: Neoadjuvant chemotherapy combined with immunotherapy in selected limited-stage small-cell lung cancer: a retrospective real-world study

Article References: Zhang, W., Zhao, W., Chen, X., Chen, X., Ye, L., Chen, Z., Huang, L., Xu, K., Liu, X., & He, Y. (2026). Neoadjuvant chemotherapy combined with immunotherapy in selected limited-stage small-cell lung cancer: a retrospective real-world study. Holistic Integrative Oncology, 5(1), Article 60. https://doi.org/10.1007/s44178-026-00278-5

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00278-5

Keywords: small-cell lung cancer, neoadjuvant therapy, immunotherapy, immune checkpoint inhibitor, chemoradiotherapy, surgery, pathologic response, overall survival, PD-1, PD-L1, thoracic oncology, retrospective study