163 Background: Being physically inactive is an independent predictor of poor outcomes in patients with stage III colon cancer. Whether physical activity can mitigate the oncologic risk of postoperative MRD is unknown. Methods: We concluded a post hoc analysis of a phase III trial evaluating celecoxib vs. placebo and 3 vs. 6 months of adjuvant chemotherapy in patients with resected stage III colon cancer. Self-reported physical activity was assessed in standardized measures of metabolic equivalent hours per week (MET-h/wk) at 2 timepoints: 1) midway through and 2) 6 months after completing adjuvant chemotherapy, modeled as a time-weighted average. MRD was determined via a clinically validated, tumor-informed circulating tumor DNA (ctDNA) assay (Signatera, Natera, Inc.). Disease-free survival (DFS) and overall survival (OS) were estimated using flexible parametric survival models. Results: Among 763 patients (median follow-up 6.0 years), 24% were highly active (≥18 MET-h/wk) and 32% were inactive (<3 MET-h/wk); 18% were ctDNA positive. Adjusting for covariates, DFS improved in patients who were ctDNA negative and moderately active (Ref: inactive; 3-17.9 MET-h/wk; HR=0.62, 95% CI [0.40-0.97]) or highly active (HR = 0.53 [0.30-0.94]). No benefit was seen among patients who were ctDNA positive (Ref: inactive; moderately active: HR = 1.20 [0.75-1.92]; highly active: HR=0.83 [0.45-1.54]). The interaction was not significant (Pint=0.269). Physical activity did not impact OS regardless of ctDNA status. The interaction of physical activity and adjuvant celecoxib use is shown in Table. Conclusions: Among patients who were ctDNA negative, physical activity was associated with improved DFS, and may demonstrate increased survival benefit alongside adjuvant celecoxib. The additive effects of both interventions were inconclusive among those who were ctDNA positive. Support: U10CA180821, U10CA180882, U24CA196171; https://acknowledgments.alliancefound.org; Natera, Pfizer; NCT01150045. Disease-free survival by physical activity level and celecoxib use, stratified by ctDNA status. 3-yr event # at risk Adjusted HR (95% CI) P-value Pint ctDNA Negative 0.258 Inactive + placebo 23 182 Ref Active + placebo 17 132 0.74 (0.43-1.28) 0.283 Inactive + celecoxib 23 167 0.92 (0.57-1.48) 0.720 Active + celecoxib 10 146 0.40 (0.22-0.79) 0.007 ctDNA Positive 0.221 Inactive + placebo 26 33 Ref Active + placebo 15 20 0.96 (0.50-1.84) 0.903 Inactive + celecoxib 34 54 0.62 (0.37-1.05) 0.076 Active + celecoxib 14 29 0.34 (0.18-0.64) 0.001 ctDNA, circulating tumor DNA; HR, hazard ratio; CI, confidence interval. Active = ≥9 MET-h/week, inactive = <9 MET-h/week. Celecoxib use defined by assignment in CALGB/SWOG 80702. Models adjusted by T and N stage, age, sex, race, assigned cycles of fluorouracil, leucovorin, and oxaliplatin, KRAS and BRAF status, BMI, and Western diet.
Predictive Role of Circulating Tumor DNA in Stage III Colon Cancer Treated With Celecoxib
Importance Observational studies have associated use of aspirin and selective cyclooxygenase inhibitors with decreased recurrence and improved survival in patients with colon cancer. While randomized clinical trials have not shown benefit across all patients, these findings suggest that select subgroups may benefit from their use. Despite the well-established prognostic value of circulating tumor DNA (ctDNA), its role in guiding treatment remains unclear. Objective To investigate the predictive value of postoperative ctDNA for survival outcomes with adjuvant celecoxib alongside conventional chemotherapy in patients with stage III colon cancer. Design, Setting, and Participants This was a post hoc analysis of the phase 3 Cancer and Leukemia Group B (now Alliance)/Southwest Oncology Group 80702 randomized clinical trial (2010-2015) assessing adjuvant celecoxib vs placebo and 3 vs 6 months of adjuvant 5-fluorouracil, leucovorin, and oxaliplatin for stage III colon cancer. Patients consented to biospecimen collection and had ctDNA analysis performed. Data analysis was performed from September 2024 to June 2025. Exposures Postoperative ctDNA positivity was determined using a clinically validated, tumor-informed 16-plex-polymerase chain reaction-next-generation sequencing assay (Signatera; Natera Inc) performed between surgery and initiation of adjuvant therapy. Main Outcomes and Measures Disease-free survival (DFS) and overall survival (OS). Survival by ctDNA status and adjuvant celecoxib use were assessed as part of a post hoc companion study with prespecified statistical analysis plan. Results Among 940 patients (mean [SD] age, 60.9 [10.8] years; 426 female [45.3%] and 515 male [54.7%] individuals; 222 [23.6%] with prior low-dose aspirin use; and median follow-up of 6.0 [95% CI, 6.0-6.0] years), 767 (81.6%) were ctDNA negative and 173 (18.4%) were ctDNA positive. ctDNA positivity was highly prognostic of worse DFS (reference, ctDNA negativity; adjusted hazard ratio [aHR], 6.12; 95% CI, 4.66-8.03) and OS (aHR, 5.86; 95% CI, 4.19-8.19). In patients with ctDNA positivity, celecoxib was associated with improved DFS (aHR, 0.61; 95% CI, 0.42-0.89) and OS (aHR, 0.62; 95% CI, 0.40-0.96) compared to placebo. Among patients with ctDNA negativity, celecoxib did not provide survival benefit (DFS: aHR, 0.76; 95% CI, 0.53-1.09; OS: aHR, 0.85; 95% CI, 0.54-1.36), although the interaction was not significant ( P for interaction, .41 and .33 for DFS and OS, respectively). These findings persisted when stratifying patients by microsatellite instability status and PIK3CA mutational status. Conclusion and Relevance The findings of this post hoc analysis suggest that ctDNA status has the potential to inform clinical decision-making among patients with stage III colon cancer who should consider adjuvant celecoxib in addition to conventional chemotherapy. Trial Registration ClinicalTrials.gov Identifier: NCT01150045
Abstract 5858: Prognostic and predictive role of T cell infiltration in stage III colon cancer (CC) treated with celecoxib: CALGB/SWOG 80702
Observational studies have demonstrated that aspirin and/or PTSG2 inhibitor (e.g., celecoxib) use, before or after colon cancer (CC) diagnosis, is associated with a lower risk of recurrence. However, a randomized trial of adjuvant celecoxib therapy in stage III CC did not show improved survival compared to placebo treatment. We therefore hypothesized that immune microenvironment features may identify patient subgroups with stronger survival benefits from anti-inflammatory celecoxib treatment. Drawing from an NCI-Intergroup trial (Cancer and Leukemia Group B [now Alliance for Clinical Trials in Oncology]/SWOG 80702) for patients with stage III resected CC that compared 3 versus 6 months of adjuvant fluorouracil, leucovorin, and oxaliplatin ± 3 years of celecoxib, we conducted tissue-based tumor microenvironment profiling on 1,098 resected tumors using a custom 9-plex, T-cell multiplex immunofluorescence assay coupled with digital image analysis and supervised machine learning. The Kaplan-Meier method was used to describe disease-free survival, based on T cell density, and log-rank testing was performed. Cox proportional hazards models were used to examine unadjusted and adjusted associations between T cell density and disease-free survival (DFS). Two-sided P values ≤0.05 were considered statistically significant. We found that higher CD3+ T cell density was associated with longer DFS with an adjusted hazard ratio (HR) of 0.69 (95% confidence interval [CI] 0.52-0.91) for patients with densities in the highest tertile as compared the lowest tertile (P=0.01). T cell subset analysis showed that stromal regulatory T helper cells (HR 0.42 comparing highest to lowest tertile, CI 0.31-0.58, P<0.001) and stromal memory cytotoxic T cells (HR 0.55 comparing highest to lowest tertile, CI 0.42-0.74, P<0.001) were most strongly associated with longer DFS. Compared to the placebo group, adjuvant celecoxib use associated with improved DFS for patients with low but not high stromal CD3+ T cell density (adjusted HRs of 0.45 [CI 0.31-0.65] for lowest tertile and 1.13 [CI 0.73-1.74] for highest tertile; Pinteraction=0.01). This association was also seen when the analysis was restricted to microsatellite stable tumors (HR 0.50 [CI 0.32-0.80] for lowest density tertile and 1.50 [CI 0.87-2.59] for highest density tertile; Pinteraction=0.01). T cell subset analysis showed that DFS benefit for celecoxib use most strongly associated with stromal memory helper T cell density (HR 0.38 [CI 0.26-0.56] for lowest density tertile and 1.26 [CI 0.80-1.97] for highest density tertile; Pinteraction<0.001). Together, these results show that while higher T cell infiltration is associated with improved DFS, lower T cell infiltration is associated with improved DFS for patients treated with celecoxib. This unexpected finding may inform immunomodulatory treatment strategies for CC. Citation Format: Yasutoshi Takashima, Chao Ma, Qian Shi, Andressa Dias Costa, Tyler Twombly, Juha P. Väyrynen, Melissa Zhao, Ardaman Shergill, Pankaj Kumar, Felix Couture, Philip Kuebler, Smitha Krishnamurthi, Benjamin Tan, Eileen M. O'Reilly, Anthony F. Shields, Shuji Ogino, Charles S. Fuchs, Jeffrey A. Meyerhardt, Jonathan A. Nowak. Prognostic and predictive role of T cell infiltration in stage III colon cancer (CC) treated with celecoxib: CALGB/SWOG 80702 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5858.
Prognostic and predictive role of circulating tumor DNA (ctDNA) in stage III colon cancer treated with celecoxib: Findings from CALGB (Alliance)/SWOG 80702.
LBA14 Background: CALGB/SWOG 80702 previously showed that the addition of celecoxib to standard adjuvant chemotherapy with FOLFOX did not significantly improve disease-free survival (DFS) in patients with stage III colon cancer. Here, we evaluated the prognostic and predictive value of ctDNA in identifying a subpopulation of patients who may benefit from celecoxib. Methods: In the subset of patients with adequate biospecimens who participated in CALGB/SWOG 80702, a randomized phase III trial of 3 versus 6 months of adjuvant 5-FU, leucovorin, oxaliplatin (FOLFOX) +/- celecoxib, ctDNA assessment was performed using a clinically validated, tumor-informed 16-plex mPCR-NGS assay (Signatera(TM), Natera, Inc.) after surgery and before the start of adjuvant therapy (baseline). The Kaplan-Meier method was used to describe the distribution of survival time based on ctDNA positivity and log-rank testing was performed. Cox proportional hazards models were used to examine unadjusted associations between ctDNA positivity and disease-free (DFS) and overall survival (OS). Two-sided P values equal to or less than 0.05 were considered statistically significant, except for interaction P values (tested with a likelihood ratio). Results: In total, 1,011 of the 2,526 patients who participated in 80702 had ctDNA testing results from baseline; 189 were ctDNA positive (18.7%). ctDNA positivity associated with male sex, higher T stage, and N2 (versus N1) stage. ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR] 6.52 [95% confident interval (CI) 5.09-8.34; p<0.0001] and OS (HR 6.28 [95% CI 4.63-8.51; p<0.0001]). Three-year DFS was 86.6% in ctDNA-negative cases and 36.8% in ctDNA-positive cases. Among patients who were ctDNA negative, celecoxib use was not significantly associated with worse DFS as compared to placebo (HR 0.75 [95% CI 0.54-1.05; p=0.095]) with a three-year DFS of 87.7% versus 85.5%, respectively. Among ctDNA-positive patients, celecoxib significantly improved DFS compared to placebo (HR 0.59 [95% CI 0.42-0.85; p=0.004]) with a three-year DFS of 44.1% versus 26.6% (P interaction = 0.25). Similar results were seen for overall survival with a hazard ratio of 0.86 (95% CI 0.56-1.33; p=0.49) for ctDNA negative cases and 0.63 (95% CI 0.41-0.96; p=0.028) for ctDNA-positive cases for celecoxib versus placebo (P interaction = 0.28). Conclusion: In a randomized phase III adjuvant therapy trial for stage III colon cancer, ctDNA was highly prognostic of DFS and OS. ctDNA positivity also appeared predictive of the benefit of adjuvant celecoxib for DFS and OS. These results suggest a potential role for ctDNA in determining which patients should consider celecoxib in addition to standard FOLFOX adjuvant therapy. Clinical trial information: NCT01150045 .
Improved Survival With Adjuvant Cyclooxygenase 2 Inhibition in PIK3CA-Activated Stage III Colon Cancer: CALGB/SWOG 80702 (Alliance)
Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. Observational studies have associated aspirin or cyclooxygenase 2 (COX-2) inhibitor usage either before or after colorectal cancer diagnosis with lower risk of recurrence and suggest that PIK3CA mutational status is predictive of better response to COX-2 inhibition. To prospectively test whether adding the COX-2 inhibitor celecoxib to standard adjuvant chemotherapy reduces the risk of recurrence and improves survival, the National Cancer Institute sponsored the CALGB/SWOG 80702 trial (ClinicalTrials.gov identifier: NCT01150045 ) for patients with stage III resected colon cancer. Although the primary hypothesis for all patients did not show a statistically significant improvement in disease-free survival (DFS) with celecoxib, subgroup analysis by PIK3CA mutational status was a preplanned study. PIK3CA gain-of-function mutations were detected in 259 of 1,197 tumors with available whole-exome sequencing data. When stratified by PIK3CA status, patients with PIK3CA gain-of-function mutations treated with celecoxib exhibited improved DFS (adjusted hazard ratio [HR], 0.56 [95% CI, 0.33 to 0.96]) compared with PIK3CA wildtype patients (adjusted HR, 0.89 [95% CI, 0.70 to 1.14]), although the interaction test was nonsignificant ( Pinteraction = .13). Overall survival was similarly improved for patients with PIK3CA gain-of-function mutations (adjusted HR, 0.44 [95% CI, 0.22 to 0.85]) compared with PIK3CA wildtype patients (adjusted HR, 0.94 [95% CI, 0.68 to 1.30]; Pinteraction = .04). Although the test for heterogeneity in DFS did not reach statistical significance, the results suggest potential utility of PIK3CA to consider selective usage of COX-2 inhibitors in addition to standard treatment for stage III colon cancer.