Citations

TPS909 Background: BCG-Exposed NMIBC (a high grade recurrence within 24 months of prior BCG, but not meeting “unresponsive” criteria) is a large patient population with a critical need for more effective treatment strategies that prevent the development of BCG unresponsive disease/progression. The current standard of care is re-treatment with BCG alone, but only ~50% of patients derive clinical benefit. While intravesical gemcitabine (with or without docetaxel) is sometimes used, multiple retrospective studies have found that GemDoce is no better than re-treatment with BCG alone for patients with BCG-exposed NMIBC. A chemoimmunotherapy strategy of intravesical Gemcitabine with BCG (GemBCG) combines the two most effective, inexpensive, and commonly used treatments for NMIBC. Based on compelling biologic rationale and preclinical data, a phase I/II (n=52) trial was initiated of GemBCG in BCG-exposed NMIBC (NCT04179162). GemBCG has minimal side effects (3.8% [2/52] with Grade 3 TRAEs (no grade 4/5 seen) with similar side effects and tolerability to BCG alone. GemBCG has a outstanding early efficacy signal (6-month complete response of 97% [28/29] in patients with CIS, compared to ~50% 6-month complete response w/ BCG alone for BCG exposed CIS). GemBCG has promising preliminary longer term efficacy (18-month HG-RFS of 76% compared to ~45-55% reported with BCG alone, GemDoce, and recombinant BCG in BCG exposed NMIBC). Correlative studies support the hypothesis that the addition of gemcitabine to BCG can favorably modulate the tumor immune microenvironment. Methods: Based on the above rationale, we initiated the “GAIN” trial (A032303/ NCT07000084), a prospective, multicenter, open-label phase III study for patients with BCG-exposed NMIBC randomized to either: re-treatment with BCG only (Arm A, SOC) or Gemcitabine + BCG (GemBCG, Arm B). BCG-exposed NMIBC is defined as a high grade NMIBC (Ta, T1, Tis/CIS) that has recurred within 24 months of prior BCG, but NOT otherwise currently meeting BCG unresponsive NMIBC. The primary objective is to compare high grade recurrence-free survival (HG-RFS) between the two treatment arms. Notable aspects of the trial include: (1) the reduced burden on investigators and research teams due to the NCI’s new streamlined data initiative, (2) liberal inclusion/exclusion criteria and pragmatic design to improve generalizability of results, and (3) Cystoscopic biopsies/TURBT at week 13/month 3 for all participants (both CIS and “papillary only”) for multiple reasons including to allow for earlier detection of BCG unresponsive disease for patient safety, increased rigor of the trial, and objectively evaluate urinary biomarkers/urinary tumor DNA. Clinical trial information: NCT04179162 .

LBA629 Background: Whether BCG strain influences clinical efficacy is unclear. BCG shortages and a reliance on a single strain may impact disease outcomes. Evidence also suggests that priming with intradermal (ID) BCG vaccination prior to intravesical (IVe) BCG enhances anti-tumor immunity and cancer clearance. Co-primary objectives address these issues. Methods: The trial design calls for 924 eligible patients with BCG naïve non-muscle invasive bladder cancer (NMIBC) (HG Ta/T1 +/- CIS or CIS alone) with negative purified protein derivative (PPD) to be randomized in a 1:1:1 ratio, to IVe TICE (Arm 1), IVe Tokyo-172 (Arm 2), or ID + IVe Tokyo-172 (Arm 3) BCG, stratifying on age group and clinical stage. IVe BCG included 6 weekly instillations (induction) and three weekly instillations (maintenance) at 3 and 6 months (mo), then every 6 mo for 3 years. Objective 1 tests whether Tokyo-172 BCG is non-inferior (NI) to TICE BCG, specifying a NI hazard ratio=1.34 (84% power). Objective 2 tests whether priming with ID prior to IVe Tokyo-172 is superior to IVe Tokyo-172 (HR=0.71, 83% power). The primary endpoint is high-grade recurrence-free survival (HG-RFS) censored at last cystoscopy, using a one-sided α=0.021 for each test. A Cox model adjusting for the stratification factors is used. Secondary endpoints include adverse events, 6-mo biopsy-proven complete response (CR) in patients with CIS +/- Ta, T1, duration of CR, PPD conversion and HG-RFS, progression-free survival (PFS) and quality of life. Max follow-up is 5 years. Results: 1000 (984 eligible) patients were enrolled from 2/17-12/20. Median (IQR) follow up is 4.6 (3.6, 5.0) yrs. Median age (range) is 70 yrs (26, 99), 17% are female, 9% are non-white, and 34% had CIS at entry. HG-RFS, CR, duration of CR at 4 yrs, and PFS were similar among arms (Table). PPD conversion occurred in 29% and was not correlated with HG-RFS. Gr 1-2 AE rate was similar (67%, 71%, and 67%) and Gr 3-4 (no Gr 5s) rate was 6%, 11%, and 14% for Arms 1,2, and 3, respectively. Conclusions: Tokyo-172 is non-inferior to TICE BCG in terms of HG RFS and CIS CR and is similar for PFS. Gr 3-4 AE rate is higher with Tokyo-172. Priming with Tokyo-172 BCG does not improve HG RFS. PPD conversion is not prognostic. Clinical trial information: NCT #03091660 . CIS Component N (eligible) 5-yr HG RFS HG RFSHR (95.8% CI) @ 5-yrPFS PFS HR(95% CI) @ CR %(95% CI) 4 yr CR duration Tice Ive 333 (330) 58% 79% 62%; 71/114(53%, 71%) 80% Tokyo Ive 332 (327) 64% *0.82(0.63, 1.08) 79% *0.99(0.70, 1.39) 60%; 66/110(50%, 69%) 83% Tokyo ID + Ive 335 (327) 63% **1.00(0.76, 1.33) 77% **1.07(0.76, 1.51) 63%; 69/109(54%, 72%) 80% 3 mo. PPD + conversionY vs. N 782 evaluable225 (29%)557 (71%) 69%67% ^HR=0.91(0.68, 1.22) * Tokyo-172 vs. Tice, ** Tokyo Priming vs. Tokyo no priming. ^conversion to PPD + vs. – @ adjusted for 2 strat factors (and arms for PPD model). PFS event = MIBC, metastasis, or death.

Abstract Background Physical activity is associated with lower colorectal cancer (CRC) risk, but its association with molecular subtypes defined by genetic and epigenetic alterations of the disease is unclear. Such information may enhance the understanding of the mechanisms related to the benefits of physical activity. Methods Pooled observational (cases: n = 5386; controls: n = 6798; studies n = 5) and genome-wide association data (cases: n = 8178; controls: n = 10 472; studies n = 5) were used. We used multivariable logistic regression models and Mendelian randomization to assess the association between physical activity and the risk of CRC subtypes defined by individual tumor markers (and marker combinations), namely microsatellite instability status, CpG island methylator phenotype status, and BRAF and KRAS mutations. We used case-only analysis to test for differences between molecular subtypes. We applied Bonferroni correction to account for multiple tests. Results In the pooled observational analysis, higher levels of physical activity were associated with lower CRC risk (Obs-per 1SD, odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.90 to 0.97), with an association that was stronger in males (Obs-per 1SD, OR = 0.91, 95% CI = 0.87 to 0.96) than in females (Obs-per 1SD, OR = 0.97, 95% CI = 0.91 to 1.03; Pinteraction = .04). Higher physical activity was associated with a lower risk of CRC across all molecular subtypes, especially in males. There was no difference in the associations by subtypes by pooled observational or Mendelian randomization analyses. The findings did not differ by study design, anatomical site, and early or late age onset of CRC. Conclusions Our findings suggest that physical activity is not differentially associated with the 4 major molecular subtypes involved in colorectal carcinogenesis, indicating that its benefits extend broadly across colorectal cancer pathogenesis.

Abstract Background Physical activity (PA) is an established protective factor for colorectal cancer (CRC), but it is unclear if genetic variants modify this effect. To investigate this possibility, we conducted a genome-wide gene–PA interaction analysis. Methods Using logistic regression and two-step and joint tests, we analyzed interactions between common genetic variants across the genome and PA in relation to CRC risk. Self-reported PA levels were categorized as active (≥ 8.75 MET-h/wk) vs. inactive (< 8.75 MET-h/wk) and as study- and sex-specific quartiles of activity. Results PA had an overall protective effect on CRC (OR [active vs. inactive] = 0.85; 95%CI = 0.81–0.90). The two-step GxE method identified an interaction between rs4779584, an intergenic variant near the GREM1 and SCG5 genes, and PA for CRC risk (p-interaction = 2.6×10 − 8 ). Stratification by genotype at this locus showed a significant reduction in CRC risk by 20% in active vs. inactive participants with the CC genotype (OR = 0.80; 95%CI = 0.75–0.85), but no significant PA–CRC association among CT or TT carriers. When PA was modeled as quartiles, the 1-d.f. GxE test identified that rs56906466, an intergenic variant near the KCNG1 gene, modified the association between PA and CRC (p-interaction = 3.5×10 − 8 ). Stratification at this locus showed that increase in PA (highest vs. lowest quartile) was associated with a lower CRC risk solely among TT carriers (OR = 0.77; 95%CI = 0.72–0.82). Conclusions In summary, we identified two genetic variants that modified the association between PA and CRC risk. One of them, related to GREM1 and SCG5 , suggests that the bone morphogenetic protein (BMP)-related, inflammatory, and/or insulin signaling pathways may be associated with the protective influence of PA on colorectal carcinogenesis.

Abstract Colorectal cancer risk can be impacted by genetic, environmental, and lifestyle factors, including diet and obesity. Gene-environment interactions (G × E) can provide biological insights into the effects of obesity on colorectal cancer risk. Here, we assessed potential genome-wide G × E interactions between body mass index (BMI) and common SNPs for colorectal cancer risk using data from 36,415 colorectal cancer cases and 48,451 controls from three international colorectal cancer consortia (CCFR, CORECT, and GECCO). The G × E tests included the conventional logistic regression using multiplicative terms (one degree of freedom, 1DF test), the two-step EDGE method, and the joint 3DF test, each of which is powerful for detecting G × E interactions under specific conditions. BMI was associated with higher colorectal cancer risk. The two-step approach revealed a statistically significant G×BMI interaction located within the Formin 1/Gremlin 1 (FMN1/GREM1) gene region (rs58349661). This SNP was also identified by the 3DF test, with a suggestive statistical significance in the 1DF test. Among participants with the CC genotype of rs58349661, overweight and obesity categories were associated with higher colorectal cancer risk, whereas null associations were observed across BMI categories in those with the TT genotype. Using data from three large international consortia, this study discovered a locus in the FMN1/GREM1 gene region that interacts with BMI on the association with colorectal cancer risk. Further studies should examine the potential mechanisms through which this locus modifies the etiologic link between obesity and colorectal cancer. Significance: This gene-environment interaction analysis revealed a genetic locus in FMN1/GREM1 that interacts with body mass index in colorectal cancer risk, suggesting potential implications for precision prevention strategies.

INTRODUCTION: Early-onset colorectal cancer diagnosed before the age of 50 years has been increasing. Likely reflecting the pathogenic role of the intestinal microbiome, which gradually changes across the entire colorectal length, the prevalence of certain tumor molecular characteristics gradually changes along colorectal subsites. Understanding how colorectal tumor molecular features differ by age and tumor location is important in personalized patient management. METHODS: Using 14,004 cases with colorectal cancer including 3,089 early-onset cases, we examined microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and KRAS and BRAF mutations in carcinomas of the cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum and compared early-onset cases with later-onset cases. RESULTS: The proportions of MSI-high, CIMP-high, and BRAF -mutated early-onset tumors were lowest in the rectum (8.8%, 3.4%, and 3.5%, respectively) and highest in the ascending colon (46% MSI-high; 15% CIMP-high) or transverse colon (8.6% BRAF -mutated) (all P trend <0.001 across the rectum to ascending colon). Compared with later-onset tumors, early-onset tumors showed a higher prevalence of MSI-high status and a lower prevalence of CIMP-high status and BRAF mutations in most subsites. KRAS mutation prevalence was higher in the cecum compared with that in the other subsites in both early-onset and later-onset tumors ( P < 0.001). Notably, later-onset MSI-high tumors showed a continuous decrease in KRAS mutation prevalence from the rectum (36%) to ascending colon (9%; P trend <0.001), followed by an increase in the cecum (14%), while early-onset MSI-high cancers showed no such trend. DISCUSSION: Our findings support biogeographical and pathogenic heterogeneity of colorectal carcinomas in different colorectal subsites and age groups.