Proposed Section Structure
This topic is best organized around the clinical decision point created by uncertain restaging after neoadjuvant chemoradiotherapy. A logical structure is: clinical background and unmet need; study design and patient groups; key pathological outcomes; subgroup interpretation by tumor histology and restaging phenotype; implications for surgery versus surveillance; limitations and generalizability; and a concise practice-oriented conclusion. That structure is used below.
Highlights
Among 205 patients with uncertain tumor response after neoadjuvant chemoradiotherapy who underwent esophagectomy in the SANO cohort, only 15% had a complete pathological response, meaning that 85% still had residual disease.
Complete pathological response rates differed by the type of uncertainty at restaging: 26% for non-traversable lesions, 10% for high-grade dysplasia, and 8% for clinical suspicion of residual tumor without pathological confirmation.
The most favorable subgroup was patients with squamous cell carcinoma and non-traversable lesions, in whom one-third achieved complete pathological response after surgery.
These data support esophagectomy for most patients with uncertain response after neoadjuvant chemoradiotherapy, while also underscoring the need for nuanced shared decision-making in selected squamous cell carcinoma cases.
Background and Clinical Context
For patients with resectable, locally advanced esophageal cancer, neoadjuvant chemoradiotherapy followed by esophagectomy has long been a standard curative-intent strategy. The pivotal CROSS trial established the oncologic benefit of preoperative chemoradiotherapy over surgery alone, with durable survival gains across both squamous cell carcinoma and adenocarcinoma. Yet the increasing recognition that some patients achieve major or complete tumor eradication after neoadjuvant treatment has raised an important question: can surgery be safely omitted in selected responders?
The Dutch SANO program has been central to this discussion. Its active-surveillance framework was built on the premise that patients with a complete clinical response after neoadjuvant chemoradiotherapy may avoid immediate esophagectomy and instead undergo close monitoring, reserving surgery for regrowth or recurrence. This is an appealing concept because esophagectomy remains a highly morbid operation with substantial effects on swallowing, nutrition, functional recovery, and long-term quality of life.
However, the weak point in any surveillance strategy is response assessment. A complete clinical response is not the same as complete pathological response, and available restaging tools are imperfect. Endoscopic biopsies can miss submucosal or patchy residual disease; endoscopic passage may be limited by stenosis; positron emission tomography and computed tomography have limited specificity for post-treatment inflammation; and even expert endoscopic ultrasonography has technical constraints after chemoradiotherapy. As a result, some patients fall into a diagnostically gray zone: they do not meet criteria for clear complete response, but they also lack definitive histologic proof of persistent invasive cancer.
The current study directly addresses that gray zone. Rather than examining obvious responders or nonresponders, it focuses on patients with an uncertain tumor response at restaging after neoadjuvant chemoradiotherapy. This is exactly the group in whom clinicians and patients face the most difficult decision: proceed to surgery despite the possibility of overtreatment, or defer surgery despite the risk of leaving residual disease behind.
Study Design
This investigation analyzed patients from the SANO cohort who underwent clinical response evaluations 4 to 12 weeks after neoadjuvant chemoradiotherapy and were classified as having an uncertain tumor response. Three clinically relevant uncertainty categories were defined: non-traversable lesions on endoscopic assessment, high-grade dysplasia on biopsy, and clinical suspicion of residual tumor without cytological or histological confirmation.
The primary endpoint was the complete pathological response rate after resection. In practical terms, this endpoint quantifies how often surgery performed for uncertainty ultimately reveals no residual viable tumor in the resected specimen. That measure is highly relevant to treatment decision-making because it estimates the extent of potential overtreatment if surgery is automatically recommended for all such patients.
A total of 272 patients met criteria for uncertain response. The distribution was 94 patients with non-traversable lesions, 50 with high-grade dysplasia, and 128 with clinical suspicion of residual tumor without pathological confirmation. Of these, 205 proceeded to esophagectomy and formed the principal pathological analysis set.
Key Results
Overall pathological findings
The headline result is clinically straightforward and highly consequential: among the 205 patients with uncertain response who underwent esophagectomy, 15% had a complete pathological response, with a 95% confidence interval of 10% to 20%. Put differently, 85% had residual disease in the resection specimen.
That finding strongly suggests that uncertainty at restaging is not a benign category. In the majority of such patients, the uncertainty reflects real residual tumor rather than a false-positive concern created by treatment-related changes alone. For surgeons, oncologists, and tumor boards, this supports maintaining a low threshold for resection when response cannot be confidently classified as complete.
Outcomes by uncertainty phenotype
The degree of residual disease risk varied substantially by the type of uncertain finding.
In the non-traversable lesions group, the complete pathological response rate was 26%: 19 of 73 resected patients, with a 95% confidence interval of 17% to 37%.
In the high-grade dysplasia group, complete pathological response occurred in 10%: 4 of 42 patients, with a 95% confidence interval of 4% to 22%.
In the group with clinical suspicion of residual tumor without cytological or histological confirmation, the complete pathological response rate was 8%: 7 of 90 patients, with a 95% confidence interval of 4% to 15%.
These numbers indicate that not all uncertainty phenotypes are equivalent. A non-traversable lesion after chemoradiotherapy is more ambiguous than high-grade dysplasia or suspicious but unconfirmed residual tumor. In contrast, when endoscopic or clinical findings raise concern for persistent malignancy despite nondiagnostic pathology, the post-resection likelihood of residual disease is high.
Histology matters: squamous cell carcinoma stands out
The most notable subgroup finding was in patients with squamous cell carcinoma and non-traversable lesions. In this subgroup, 33% achieved complete pathological response: 14 of 42 patients, with a 95% confidence interval of 21% to 48%.
This observation aligns with broader clinical experience showing that squamous cell carcinoma is generally more radiosensitive than adenocarcinoma and more likely to achieve major treatment response after chemoradiotherapy. The result does not overturn the overall message favoring surgery for uncertain response, but it introduces an important nuance. A one-in-three probability of complete pathological response is high enough to warrant careful, individualized counseling, especially in patients with high operative risk, frailty, borderline functional status, or strong preference to avoid surgery.
Clinical Interpretation
The central clinical message is that most patients with uncertain response after neoadjuvant chemoradiotherapy should still be advised to undergo esophagectomy. An 85% residual disease rate after surgery is too high to justify a default surveillance approach in this population. This is particularly true because untreated residual local disease may progress, compromise later salvageability, and increase the risk of adverse oncologic outcomes.
At the same time, the study sharpens how clinicians should think about the meaning of uncertainty. It is not merely a binary problem of complete response versus no complete response. Instead, there are distinct uncertainty states, each carrying a different probability of pathological eradication. High-grade dysplasia or suspicious findings without tissue confirmation appear to behave more like residual cancer than like treatment sterilization. Non-traversable lesions are less straightforward, and in squamous cell carcinoma especially, a substantial minority may represent post-treatment fibrosis or stenosis without viable tumor.
This distinction matters in shared decision-making. For a medically fit patient with adenocarcinoma and suspicious residual findings, the data strongly support proceeding to surgery. For a patient with squamous cell carcinoma, severe comorbidity, and a non-traversable lesion but no pathological proof of persistence, the conversation may be more balanced. Even then, surveillance would require a robust protocol, high-quality follow-up, and explicit acceptance of the possibility that residual disease could be missed.
Implications for Restaging Practice
The study also highlights the limitations of current restaging modalities after chemoradiotherapy. Endoscopic passage failure, dysplastic biopsies, and clinically suspicious but nondiagnostic findings all create uncertainty because none directly and reliably maps onto final pathology. This exposes a persistent gap in esophageal cancer management: response assessment technology has not yet achieved the precision needed to confidently spare surgery in all biologic responders.
From a translational standpoint, future progress will likely depend on better multimodal assessment. Potential directions include more standardized bite-on-bite biopsy protocols, advanced endoscopic imaging, diffusion-weighted magnetic resonance imaging where feasible, improved PET interpretation frameworks, circulating tumor DNA, and integrated prediction models combining histology, imaging, endoscopy, and clinical variables. The goal is not simply to identify complete responders, but to stratify the probability of residual disease within intermediate or indeterminate response categories.
Until such tools are validated, this study suggests that clinicians should treat uncertain response as a high-risk finding rather than as a near-complete response state.
Strengths and Limitations
A major strength of this analysis is its direct clinical relevance. The investigators examined a population that is common in practice but underrepresented in simplified responder-versus-nonresponder frameworks. The categorization of uncertainty phenotypes is practical and mirrors the real dilemmas encountered during post-neoadjuvant restaging. The use of resection pathology as the endpoint provides a robust reference standard.
The study also benefits from being embedded in the SANO cohort, which has helped define modern organ-preservation discussions in esophageal cancer. As such, the findings are highly relevant to centers already considering or implementing surveillance pathways.
Several limitations should be kept in mind. First, the abstract does not provide the full selection dynamics for why some of the 272 patients did not undergo surgery, which could introduce bias if resected patients differed systematically from those managed otherwise. Second, the report as summarized does not provide detailed survival, recurrence, or salvage outcomes for these uncertainty subgroups, so the present analysis should not be overextended into long-term oncologic equivalence. Third, the sample sizes within subgroups, especially histology-specific strata, are modest, and confidence intervals remain fairly wide. Finally, the findings arise from a specialized clinical program with structured response evaluation, which may limit generalizability to centers with less standardized post-chemoradiotherapy assessment.
How This Fits With Existing Evidence and Guidelines
Standard treatment paradigms have historically favored esophagectomy after neoadjuvant chemoradiotherapy for operable disease, largely because residual disease cannot be excluded with sufficient certainty by clinical tests alone. The active-surveillance concept has gained momentum, but only in carefully selected patients with convincing complete clinical response and under rigorous follow-up protocols.
The present study supports that cautious position. It does not argue against surveillance in genuine complete clinical responders; rather, it reinforces that patients who fall short of that threshold should generally not be assumed to have achieved pathological sterilization. In this sense, the findings are complementary to, not contradictory with, selective organ-preservation strategies.
The subgroup signal in squamous cell carcinoma is biologically plausible and clinically important. Squamous tumors often achieve deeper response to chemoradiotherapy than adenocarcinomas, which is reflected in prior trials and retrospective series. But even in this subgroup, the data do not support abandoning surgery wholesale. Instead, they provide a basis for more sophisticated risk communication when the uncertainty phenotype is specifically a non-traversable lesion.
Practice Takeaways for Multidisciplinary Teams
For tumor boards, several practical conclusions emerge.
First, uncertain response after neoadjuvant chemoradiotherapy should usually be treated as probable residual disease, not as likely complete response.
Second, the reason for uncertainty matters. High-grade dysplasia and clinically suspicious but unconfirmed residual disease carry relatively low complete pathological response rates after resection and should generally push the balance toward surgery.
Third, non-traversable lesions are a more heterogeneous category. In squamous cell carcinoma especially, clinicians should recognize a higher chance of pathological complete response and incorporate that information into individualized counseling.
Fourth, any decision to defer surgery in an uncertain responder should be exceptional, explicitly documented, and supported by a high-quality surveillance infrastructure.
Funding and ClinicalTrials.gov
The abstract provided does not report funding details for this specific analysis. The parent SANO study group is named, but a funding source is not listed in the abstract summary supplied here. A ClinicalTrials.gov registration number is also not provided in the abstract text supplied.
Conclusion
This SANO cohort analysis addresses one of the most difficult questions in contemporary esophageal cancer care: what to do when restaging after neoadjuvant chemoradiotherapy is inconclusive. The answer, based on pathology, is that uncertainty usually means residual disease. Among patients who underwent esophagectomy, 85% had persistent tumor, strongly supporting resection for most patients in this setting.
The important exception is not a change in standard practice, but a refinement of clinical judgment. Patients with squamous cell carcinoma and non-traversable lesions appear to have a relatively high probability of complete pathological response, and that signal should inform nuanced shared decision-making. Even so, current evidence still favors surgery for the majority of uncertain responders until more accurate response-assessment tools can reliably identify those who can safely avoid it.
In short, the study strengthens the case for esophagectomy when response after chemoradiotherapy is equivocal, while also identifying a subgroup in which uncertainty may be more biologically favorable than it first appears.
References
1. Gangaram Panday SSG, In ‘t Veld D, Mostert B, Doukas M, van der Zijden CJ, van Lanschot JJB, Coene PLO, Dekker JWT, Hartgrink HH, Hazen WL, Kouwenhoven EA, Nieuwenhuijzen GAP, Pierie JP, Rosman C, van Sandick JW, Sosef MN, Spaander MCW, van der Zaag ES, van der Sluis P, Lagarde SM, Wijnhoven BPL, SANO Study Group. Pathological Outcomes After Uncertain Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer. Annals of Surgery. 2026-05-25. PMID: 42184346.
2. van Hagen P, Hulshof MCCM, van Lanschot JJB, et al. Preoperative chemoradiotherapy for esophageal or junctional cancer. New England Journal of Medicine. 2012;366(22):2074-2084. doi:10.1056/NEJMoa1112088.
3. Lordick F, Mariette C, Haustermans K, Obermannová R, Arnold D; ESMO Guidelines Committee. Oesophageal cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Annals of Oncology. 2022;33(10):992-1004. doi:10.1016/j.annonc.2022.07.003.
4. Shapiro J, van Lanschot JJB, Hulshof MCCM, et al. Neoadjuvant chemoradiotherapy plus surgery versus surgery alone for oesophageal or junctional cancer: long-term results of the randomized CROSS trial. Lancet Oncology. 2015;16(9):1090-1098. doi:10.1016/S1470-2045(15)00040-6.
