Citations

687 Background: The NAPOLI 3 study (NCT04083235, N = 770) reported that NALIRIFOX improved overall survival (OS) vs Gem+NabP with manageable toxicity in 1L treatment of metastatic pancreatic adenocarcinoma. We explored changes in CA19-9 levels and their potential associations with efficacy as an important tumor marker in pancreatic adenocarcinoma. Methods: In NAPOLI 3, CA19-9 was evaluated at baseline and every 8 weeks until patients discontinued study treatment. The detection limit of CA19-9 was 8000 kU/L in this study. The Cox proportional hazards regression and logistic regression were employed to investigate the relationship between CA19-9 decrease and OS, progression-free survival (PFS), and overall response rate (ORR). Results: Patients with evaluable CA19-9 (levels =< 8000) at baseline and additional measurements at weeks 8 and 16 were included in the analysis (NALIRIFOX, n = 179; Gem+NabP, n = 194). The median baseline CA19-9 level was 378.0 and 409.7 kU/L for the NALIRIFOX and Gem+NabP arms, respectively. Overall, patients with (vs without) any CA 19-9 decrease by week 16 had a higher ORR (59.9% vs 35.2%; p = 0.002), a longer median PFS (9.2 vs 6.2 months; p < 0.001) and a longer median OS (14.2 vs 8.7 months; p = 0.005), respectively in a pooled analysis of the treatments. In the NALIRIFOX arm, patients with any CA19-9 decrease by week 16 had a higher confirmed ORR of 65.1% compared with those without at 42.4% ( p < 0.001), a median PFS of 9.5 vs 7.1 months ( p < 0.001) and a median OS of 15.4 versus 8.4 months ( p = 0.004), respectively. In the Gem+NabP arm, patients with CA19-9 decrease by week 16 had a higher ORR of 55.5% compared with those without at 23.8% ( p = 0.012), a median PFS of 7.6 versus 5.8 months ( p < 0.001) and a median OS of 13.7 versus 11.9 months ( p = 0.235), respectively. Conclusions: CA19-9 decrease by week 16 has the potential to be an early prognostic factor for OS, PFS and ORR. The results should be interpreted with caution as a considerable percentage of patients were excluded due to non-evaluable CA19-9 that exceeded the lab detection limit of 8000 kU/L. Clinical trial information: NCT04083235 .

67 Background: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality among men and women combined in the United States (US). Although the national screening rate has increased over the years, it remains below the target of 80% recommended by the National Colorectal Cancer Roundtable for improved CRC outcomes. In most recent years, and particularly during COVID-19, screening-eligible individuals preferred at-home, non-invasive screening options over invasive tests such as colonoscopy due to convenience and accessibility. The objective of this study was to understand the CRC screening trends over the last two decades, and the impact of various screening modalities on the overall CRC screening rate. Methods: Using National Health Interview Survey (NHIS) data from 2005 onwards, we examined CRC screening (colonoscopy, mt-sDNA, FIT/FOBT, and sigmoidoscopy) rates among adults aged 50-75 years. A pseudo-time-series cross-sectional (pseudo TSCS) analysis was conducted including random effects Generalized Least Square (GLS) regression model to estimate the relative impact of each modality on the overall increase in CRC rates from 2018 to 2021. Results: Among 50-75 years old individuals, the estimated CRC screening use increased by 32% from 2005 to 2021 (47.7% to 69.9%). Between 2018 to 2021, the rates increased from 64% to 70%, driven largely by increased use of mt-sDNA, a 62.1% increase from 2018 to 2021 (2.5% to 6.6%). During this time period, colonoscopy utilization increased by 4.4% (61.2% to 64.0%), while FOBT/FIT utilization increased by 3.6% (5.3% to 5.5%). A pseudo-TSCS analysis showed that mt-sDNA contributed substantially to the overall CRC screening rate increase during years 2018-2021 (77.3%; p < 0.0001). Conclusions: While CRC screening rates are increasing, they remain below the national goal of 80%. Mt-sDNA as a home-based, non-invasive screening, recommended at a 3-year interval, has been leveraged to improve overall CRC screening rates, particularly to address the screening backlog created during the COVID-19 pandemic. A collaborative approach between healthcare providers and screening-eligible individuals is needed to empower patients with choice for their CRC screening modality to achieve the national goal.

664 Background: Postoperative complications in patients with borderline resectable pancreatic cancer treated with neoadjuvant therapy and pancreatectomy in the national cooperative group setting have not been previously characterized. Further, the impact of preoperative hypofractionated radiotherapy on postoperative outcomes is largely unknown. We sought to quantify perioperative morbidity among patients with pancreatic cancer who received neoadjuvant modified FOLFIRINOX chemotherapy with or without hypofractionated radiotherapy on a multicenter clinical trial. Methods: The A021501 phase 2 trial randomized patients with borderline resectable pancreatic ductal adenocarcinoma to 8 doses of mFOLFIRINOX (Arm 1) or 7 doses of mFOLFIRINOX then hypofractionated radiotherapy (Arm 2), followed by pancreatectomy (Dec 31, 2016-Jan 1, 2019). Patients underwent resection according to defined operative standards at enrolling centers without specific requirements for either surgeon or hospital volume. Surgical complications and adverse events were assessed and captured at a single time point of 90 days after surgery and compared between treatment arms. Results: Of 126 enrolled patients, 51 (40%) underwent pancreatectomy (n=32, Arm 1; n=19, Arm 2) at 28 institutions. Vascular resection was performed in 19 patients (37%). One patient in Arm 2 died within 90 days after surgery. Rates of any surgical complication were 19% (n=6) in Arm 1 and 42% (n=8) in Arm 2 (p=0.07). Median length of stay was 7 days (range 5-38 days). Five (10%) patients required reoperation within 90 days. Readmission rates were higher in Arm 2 than Arm 1 (16% vs. 42%, p=0.04) but there were no differences in rates of reoperation, pancreatic fistula or abscess requiring drainage, or wound infection between study arms. 54% of patients (n=26/48) experienced a grade 3 or higher adverse event, with no difference between treatment arms (47% versus 67%, p=0.7). Rates of initiation of adjuvant therapy did not differ between treatment arms (66% vs. 68%, p=0.4). Pancreatic fistula and abscess were associated with adjuvant therapy (p<0.01). No difference in overall survival was observed based on occurrence of surgical complications (HR 1.1; 95% CI 0.5-2.6). Conclusions: In this national cooperative group study of patients with borderline resectable pancreatic cancer,postoperative complications following neoadjuvant chemotherapy, radiation, and surgical resection were consistent with rates previously reported by high-volume institutions and using large datasets. Multimodality trials of preoperative therapy for locoregionally advanced pancreatic cancer may be safely performed in the cooperative group setting. Clinical trial information: NCT02839343 .

592 Background: The introduction of peptide receptor radionuclide therapy (PRRT) using Lutetium-177 (177Lu) DOTATATE has led to a paradigm shift in the treatment of neuroendocrine tumors (NETs). Hematological toxicity is a well-recognized adverse effect (AE) of 177Lu DOTATATE. Most cytopenias are transient, with an estimated incidence of 10-25%, typically mild to moderate in severity (grade G1-2). The most dreaded AE of PRRT is therapy-related myeloid neoplasm (t-MN), with an estimated 2-8% incidence and a higher incidence reported in patients who also received prior chemotherapy. We sought to evaluate the hematological safety of 177Lu PRRT in the setting of NETs with extensive (i.e., innumerable) bone metastases. Methods: We retrospectively reviewed the medical records of all Mayo Clinic patients (pts) with extensive/innumerable osseous metastases, defined as >50% skeletal involvement by positron emission tomography (PET) DOTATATE, who were treated with 177Lu DOTATATE. Pts characteristics and laboratory results were collected before, during, and after 177Lu DOTATATE treatment. Hematotoxicity was graded according to the NCI-CTCAE v5. Results: Out of 27 pts, 13(48%) developed cytopenia(s) of any grade after treatment with one or more cycles of 177Lu DOTATATE. In total, there were 13(48%) pts with anemia, 13(48%) with thrombocytopenia, and 6(22%) with neutropenia. Six (22%) pts had severe hematological toxicity (G3-4). Twelve months post-PRRT, 7(26%) pts continued to experience cytopenia(s) of any grade, of whom 4(15%) had G3-4 hematotoxicity. One pt developed t-MN, and two pts had myelophthisis on bone marrow biopsy from infiltrating NET. 16(59%) pts received cytotoxic chemotherapy before PRRT, and 7(25.9%) developed subsequent cytopenia(s). Overall, 15(55%) pts completed four cycles, while 3 pts didn’t complete four cycles of 177Lu DOTATATE due to hematotoxicity. Conclusions: Pts with advanced NETs and extensive/innumerable bone metastases treated with PRRT could be at higher risk for myelosuppression than historical controls. Our study highlights the importance of carefully monitoring and assessing hematological parameters in pts being considered for 177Lu DOTATATE with extensive/innumerable bone metastasis. [Table: see text]

55 Background: Nearly one-half of deficient mismatch repair (d-MMR) metastatic colorectal cancers (mCRC) demonstrate durable responses to immune checkpoint inhibitors (ICIs). Given preclinical data indicating that liver metastases sequester activated CD8+ T cells from systemic circulation, we examined clinical outcome by metastatic site. Methods: In a retrospective cohort of patients with d-MMR mCRCs treated at multiple centers in France (n=66), we sought to validate data from a U.S. cohort, and then performed pooled analysis (n=104). All patients received first-line ICI monotherapy. Metastatic site was analyzed in relationship to tumor response (RECIST version 1.1), and progression-free survival (PFS) by multivariable stratified Cox regression after adjustment for covariates. Results: Objective responses were achieved in 38/66 (58%) patients in the validation cohort. Best tumor response included 13 (20%) complete responses (CR), 25 (38%) partial responses (PR), 16 (25%) stable disease, and 11 (17%) progressive disease (PD). One-year and 5-year PFS rates were 73% and 67%, respectively; 18 (27%) patients progressed during immunotherapy. Best tumor response was attenuated in patients with liver metastasis ( P=0.03). Presence of liver metastasis, but not other sites, was associated with significantly poorer PFS after adjustment for covariates (HRadj 2.82; 95%CI, 1.08-7.39; Padj=0.03). In a pooled analysis, liver metastasis remained significantly and independently associated with poorer PFS (HRadj 3.18; 95%CI, 1.52-6.67; Padj=0.002) and with attenuated tumor best response (P=0.01). Conclusions: Metastasis to the liver, but not other sites, was validated as an independent factor associated with poorer response and survival after ICI treatment in d-MMR mCRCs. These data underscore the need for novel therapeutic strategies in these patients. [Table: see text]

538 Background: In biliary tract cancer (BTC), TP53 is the most commonly altered gene and may co-occur with KRAS alteration. The presence of a co-alterations in of TP53 and KRAS is associated with poor prognosis in many cancers. In patients (pts) with advanced BTC, the prognostic implications of such co-alterations have not been fully investigated. Methods: This is a pooled analysis of SCRUM-Japan GOZILA and MONSTAR-SCREEN-1 and -2 studies. Genomic profiling was conducted with Guardant360 for plasma in GOZILA, FoundationOne CDx for tissue and FoundationOne Liquid CDx for plasma in MONSTAR-SCREEN-1, and CARIS MI Profile for tissue in MONSTAR-SCREEN-2. Pts with advanced BTC receiving systemic therapy were included in this study. Results: Among 636 pts with advanced BTC, 85 had TP53/KRAS co-alteration, 293 had TP53, 44 had KRAS, and 214 had neither KRAS nor TP53 alteration (WT/WT). Tumors with TP53 alteration had significantly higher level of tumor mutation burden (TMB) compared to the other groups (3.8 mut/Mb for TP53/KRAS, 5.0 mut/Mb for TP53, 2.8 mut/Mb for KRAS, and 2.5 mut/Mb for WT/WT, respectively, P<0.001). In addition, the frequency of microsatellite instability-high (MSI-High) in the TP53/KRAS group (11.0%) was significantly higher compared to the TP53 group (3.1%, P<0.05), and the WT/WT group (0.6%, P<0.001), respectively. The objective response rate of first-line therapy in the TP53/KRAS group (8.2%) was significantly lower than in the other groups (20.8% for TP53, 23.3% for KRAS, and 19.7% for WT/WT groups, P=0.035). There was no pts treated with durvalumab plus gemcitabine and cisplatin. Two pts with TP53/KRAS alteration and MSI-High received pembrolizumab monotherapy, and partial response was achieved with a progression-free survival of 9.4 and 22.0 months. The median overall survival (OS) for pts treated with first-line therapy of the TP53/KRAS, KRAS, TP53, and WT/WT groups were 13.6 (95% confidence interval [CI], 11.5-15.5), 14.3 (95%CI, 9.7-25.9), 18.8 (95%CI, 16.9-20.6), and 22.7 months (95%CI, 20.4-25.9), respectively. Multivariate analysis identified TP53/KRAS alteration (hazard ratio [HR] 2.14, 95%CI 1.43-3.22, P<0.001), number of detected variants (≥2) (HR 1.50, 95%CI 1.04-2.16, P=0.029), locally advanced (HR 1.72, 95%CI 1.05-2.83, P=0.033), and metastatic status (HR 1.78, 95%CI 1.39-2.28, P<0.001) as independent prognostic factors for shorter OS. Conclusions: Patients with advanced BTC with co-occurring TP53/KRAS alterations have worse prognosis. Interestingly, the presence of these co-alterations was associated with a higher likelihood of MSI-High phenotype.

507 Background: Navitoclax (ABT-263) is an oral Bcl-2 homology-3 mimetic that binds with high affinity to pro-survival Bcl-2 proteins, resulting in apoptosis. Sorafenib, an oral multi kinase inhibitor inhibits tumor angiogenesis and also promotes apoptosis. The efficacy of either agent alone is limited; however, preclinical studies demonstrate synergy with the combination of navitoclax and sorafenib. Methods: In this phase 1 pharmacokinetic and pharmacodynamic study (NCT01364051), we evaluated the combination of navitoclax and sorafenib in a dose escalation cohort of patients with refractory solid tumors, with an expansion cohort in hepatocellular carcinoma (HCC). The study agents were provided by the Cancer Therapy Evaluation Program at National Cancer Institute under CRADA. Navitoclax and sorafenib were administered continuously on days 1 through 21 of 21-day cycles. The maximum tolerated dose (MTD) was determined using the continual reassessment method. Results: Ten patients were enrolled in the dose escalation cohort and 15 patients with HCC were enrolled in the expansion cohort. Two dose levels were tested, dose level 1 (navitoclax 150 mg daily plus sorafenib 400 mg twice daily) and dose level 2 (navitoclax 200 mg daily plus sorafenib 400 mg twice daily). At dose level 1, one dose limiting toxicity (DLT) [grade 3 aspartate aminotransferase elevation] was observed among 6 patients treated at this dose level. In a cohort of 3 patients treated at dose level 2, two DLTs were observed (grade 3 hypertension, and grade 3 rash), hence dose level 1 was identified as the MTD. Among all patients, the most common grade 3 toxicity was thrombocytopenia (5 patients, 20%): there were no grade 4 or 5 toxicities (Table). Patients received a median of 2 cycles (range 1-36 cycles) and all patients were off study treatment at data cut off. Six patients in the expansion cohort had stable disease, 5 had progressive disease and 4 with unavailable data. There were no partial or complete responses. Drug-drug interaction between navitoclax and sorafenib was not observed. The combination of navitoclax and sorafenib did not increase induction of apoptosis compared with navitoclax alone. Conclusions: Navitoclax plus sorafenib resulted in manageable, but not ideal toxicities for continuous oral administration which precluded dose escalation. The lack of clinical benefit in the HCC expansion cohort does not support further development of this combination for the treatment of advanced HCC. Clinical trial information: NCT01364051 . [Table: see text]

454 Background: Biliary tract cancers (BTC) are often diagnosed at advanced stages (aBTC) when prognosis is poor. In the Phase 3 TOPAZ-1 study (NCT03875235), durvalumab plus gemcitabine and cisplatin (GemCis) significantly improved overall survival versus placebo plus GemCis. To better understand the context of the TOPAZ-1 trial results in the US, we looked at first-line (1L) treatment patterns in participants with aBTC treated with GemCis and other gemcitabine (Gem)-based chemotherapy (CT) regimens. Methods: This retrospective observational cohort study used linked electronic health records and medical and pharmacy claims data from the Optum Market Clarity Database. Adults diagnosed with de novo or recurrent aBTC, who initiated 1L Gem-based CT between January 2016 and March 2022, were identified and followed from the index date (defined as the first administration of Gem-based CT on or after initial BTC diagnosis date) until death, end of continuous enrollment, or end of study period, whichever occurred first. Variables including patient demographics, clinical characteristics, and treatment patterns were described. Results: A total of 580 patients were included in the analysis with either de novo aBTC (n=481, 82.9%) or recurrent aBTC (n=99, 17.1%) with median follow-up time of 10.4 (interquartile range: 6.4, 17.5) and 12.0 (interquartile range: 6.3, 21.9) months, respectively. Mean (SD) age was 64.6 (11.2) and 66.8 (10.4) years, with 45.7% and 54.5% male in the de novo and recurrent aBTC groups, respectively. Most patients were white (77.6%). The most frequent site of primary tumor diagnosis was single-site intrahepatic (overall 62.8%, de novo 66.7%, recurrent 43.4%). In the 12 months prior to index date, 38.5% of patients had biliary obstruction, 30.2% had biliary stents, 29.3% had jaundice, and 17.1% had nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Common comorbidities included cardiovascular disease (50.9%), obesity (46.8%), and diabetes (35.2%). The most common 1L CT was GemCis followed by Gem for both the de novo (n=355, 73.8% and n=36, 7.5%) and recurrent groups (n=58, 58.6% and n=26, 26.3%), respectively. Approximately half of participants (50.9%) switched to a new line of treatment, 33.3% discontinued 1L CT, and 15.9% remained on 1L CT at last follow-up. Most frequent 2L treatments included fluorouracil/oxaliplatin (36.9%) and capecitabine (14.2%). Further analysis will characterize outcomes and regimen duration. Conclusions: Findings from this retrospective study showed that the most common 1L therapies were GemCis and Gem among both de novo and recurrent patients with aBTC. These results provide insight into aBTC treatment practices and may help inform treatment decisions.

434 Background: Tinengotinib is a spectrum-selective multi-kinase inhibitor with unique binding properties to FGFR, potently inhibited FGFR2 fusion/rearrangement and acquired resistant mutations in pre-clinical models and in phase I trials that included cholangiocarcinoma (CCA) patients (pts). Here we present the efficacy and safety of tinengotinib in a phase II clinical trial. Methods: Eligible pts with advanced/metastatic CCA who had received ≥ 1 prior systemic chemotherapy therapy and ECOG PS 0 or 1 were treated with tinengotinib 10 mg QD. Four cohorts included: Cohort A1: FGFR2 fusion(s) with primary progression on previous FGFR inhibitor ( FGFRi), A2: FGFR2 fusion(s) with progression after prior response to FGFRi (acquired resistance); B: non-fusion FGFR alteration(s): C: FGFR wild-type ( FGFRwt). Primary endpoint was objective response rate (ORR) per RECIST v1.1. CTCAE V5.0 was used for safety assessments. Results: As of 7Aug2023, 48 pts with CCA were enrolled, 13 in Cohort A1, 10 in A2, 12 in B, 13 in C. Median age 61.5 [range 25-81] years old, 41.7% male, 58.3% had ≥ 3 lines of prior therapy. ECOG PS 0 in 47.9% pts. Among 35 pts with FGFR alterations, 80.0% had ≥ 1 prior FGFRi therapy, and 97.1% had prior chemotherapy. Forty (40) pts were efficacy evaluable. In A1, 1 out of 11 pts (9.1%) achieved PR with tumor reduction of 31.8%. In A2, 3 out of 8 pts (37.5%) achieved PR with tumor reduction of 40.7%, 47.0% and 54.6%. In B, 3 out of 9 pts (33.3%) achieved PR with tumor reduction of 36.5%, 48.6%, and 60.6%. No PR was observed in C. Overall DCR was 94.7% (18/19) in FGFR2 fusion/rearrangement pts (A1+A2), 88.9% (8/9) in other FGFR alterations pts (B), and 75% (9/12) in FGFRwt pts (C). Median progression-free survival (mPFS) was 5.26 months (95%CI, 2.86-9.10) in A1+A2, 5.98 months (95%CI, 1.87-NA) in B and 3.84 months (95% CI, 1.84-4.80) in C. Among 48 treated pts, treatment-related AEs (TRAEs) occurred in 45 (93.8%) pts, 14 (29.2%) in G1-2, 29 (60.4%) in G3 and 2 (4.2%) in G4. The most common G3 TRAEs were hypertension in 12 (25%), palmar-plantar erythrodysesthesia syndrome in 3 (6.3%), diarrhea in 3 (6.3%) and stomatitis in 3 (6.3%). One subject had G4 increased TSH and G4 increased lipase, and another subject had G4 posterior reversible encephalopathy syndrome. No G5 TRAE was observed. Conclusions: Tinengotinib has promising clinical benefit for FGFR2 fusion CCA after prior FGFRi and for non-fusion FGFR alterations. Tinengotinib-related toxicities were manageable. An ongoing randomized, controlled phase III study will evaluate the clinical efficacy, safety, and pharmacodynamic effect of Tinengotinib vs Physicians’ choice in subjects with FGFR2-altered refractory/relapsed CCA after prior chemotherapy and FGFRi therapy. Clinical trial information: NCT04919642 .

31 Background: Incidence of early-onset colorectal cancer (eoCRC, <50 years of age at diagnosis) is increasing globally. However, little is known regarding symptom burden in this sub-population. We compared symptoms in patients with eoCRC to those of patients with average-onset CRC (aoCRC, diagnosed at age ≥ 50). Methods: E2C2 is a stepped-wedge, cluster-randomized pragmatic trial evaluating a collaborative care model for the assessment and management of six symptoms [Sleep disturbance, Pain, Physical function impairment, Anxiety, emotional Distress, and Energy deficit (SPPADE)]. Patients were asked to complete assessments rating each of these symptoms on an 11-point numerical rating scale. Symptom severity was classified as mild (0-3), moderate (4-6), or severe (7-10). We conducted a subgroup analysis of patients with CRC, comparing SPPADE symptoms on an initial survey, regardless of timing in treatment course, between patients with eoCRC and aoCRC. Results: Patients with CRC (n=4281) completed a survey between March 2019 and December 2022. Patient demographics and SPPADE symptoms are reported in the table. Patients with eoCRC were more likely to report severe sleep disturbance ( p<0.0001), pain ( p=0.03485), anxiety ( p<0.0001), emotional distress ( p<0.0001), and fatigue ( p=0.01083). In patients with eoCRC, women were more likely to report severe pain (12.6% vs 6.9%, p=0.0069), anxiety (16.1% vs 10.0%, p=0.012), emotional distress (12.1% vs 5.4%, p=0.00066), fatigue (18.9% vs 13.4%, p=0.038), and physical function impairment (10.1% vs 5.8%, p=0.026) compared to men. Conclusions: Patients with eoCRC reported higher symptom severity than patients with aoCRC. This suggests unique needs for symptom management in patients with eoCRC. Additional research is needed to evaluate how time since diagnosis, disease characteristics, cancer-directed treatment patterns, and co-occurring symptoms are associated with specific symptoms in this population. [Table: see text]