Citations

e20615 Background: Patients with Stage IV NSCLC have a poor prognosis, with approximately 25-30% succumbing to the disease within the first three months. However, survival outcomes can vary significantly depending on individual factors and advancements in treatment options. Therefore, it is crucial to identify patients at high risk of poor survival outcomes to tailor personalized treatment strategies and optimize clinical management. An international study has been conducted to generate prognostic scores for patients with Stage IV NSCLC. Methods: A retrospective observational study was conducted using real-world data (RWD) from South Korea (ROOT-HEALTH database from Samsung Medical Center), the USA (COTA NSCLC dataset) and France (CIAN lung cohort from Centre Léon Bérard). Patients with stage IV NSCLC between January 2008 and December 2023 were included. The study's primary objective was to learn from patients ‘baseline characteristics affecting overall survival (OS) and progression-free survival (PFS) to derive a prognostic score reflecting relative risk of death for given patient. A partition strategy was used, with 70% of the cohort for training and 30% for validation. Data-driven feature elimination has been applied to avoid overfitting of the models. Nested cross-validation reduced selection bias in hyperparameter tuning and model selection. Results: A total of 7,805 patients with NSCLC were included in the final analysis (USA: n=610, France: n=271, Korea: n=6,924). In the Korean dataset, the model achieved a C-index of 0.872 for OS using 35 selected variables. For the USA dataset, the model, based on 15 selected variables, demonstrated a C-index of 0.707 for OS. For PFS, the Korean dataset demonstrated a C-index of 0.823, the USA dataset achieved a C-index of 0.664, and the French dataset reported a C-index of 0.64, using 15 selected variables. The important predictors for OS included albumin, neutrophil/lymphocyte ratio, bilirubin, and druggable mutations. For PFS, important predictors included LDH, albumin, hemoglobin, MET mutation, bilirubin, and BMI. The prognostic scores derived from these models allowed to identify patients with higher risk of death, than average, in each country. Conclusions: This study generates prognostic scores for OS and PFS in stage IV NSCLC using longitudinal international data from the USA, France, and South Korea throughout the cancer journey. It has the potential to support better treatment strategy for severe patients in clinical practice and early decision-making in clinical studies. Further research utilizing diverse international cohorts is essential to refine prognostic scores and enhance personalized treatment strategies for stage IV NSCLC patients.

3535 Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy in patients (pts) with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of pts with mCRC receiving BV plus first-line chemotherapy (CT). Incidence rate, temporal pattern, and potential risk factors associated with gastrointestinal perforation (GIP) were explored. Methods: Baseline patient characteristics (BC), including prospectively identified potential risk factors for GIP, were collected at study entry. Safety data were collected every 3 months (mo). Logistic regression models, adjusted and unadjusted for treatment assignment, were used to identify BC potentially associated with GIP. Results: 1968 pts were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo as of Nov 4, 2005. GIPs were observed in 34 pts (1.7%). For pts with GIP, median time to first event was 2.1 mo; the majority of events were non-fatal and occurred within the first 3 mo after starting BV. BC including GI medical history (chronic aspirin or NSAID use, peptic ulcer disease, diverticulosis) were similar in pts with or without GIP and with earlier or later GIP onset (≤ or >3 mo from start of BV). Although adjusted models did not show any significant BC, GIP rates were numerically higher in pts with primary tumor intact (2.6%) vs. resected (1.6%). Furthermore, univariate analyses revealed a significant difference between intact (2.3%) and resected (0.8%) primary tumor for earlier GIP (≤3 mo from start of BV). The majority of pts with GIP had at least one of the following: acute diverticulitis, intra-abdominal abscess, gastrointestinal obstruction, tumor at GIP site, abdominal carcinomatosis, prior abdominal or pelvic radiation therapy. Conclusions: Preliminary analyses indicate the incidence of GIP in this large, community-based observational registry is similar to that previously reported in phase III mCRC trials with BV. No associations between specific BCs and an increased risk of GIP were identified. Patients with primary tumor intact were more likely to incur a GIP within the first 3 mo of starting BV and CT. [Table: see text]

3516 Background: A previous report noted that patients (pts) in the phase III study of IFL ± BV who received BV had significantly longer PFS and OS regardless of whether or not they responded according to RECIST criteria (Mass et al, ASCO 2005). It is unclear if this phenomenon is specific to the addition of a biologic to chemotherapy (CT) or a more general benefit from improved therapy since it has been suggested that stable as well as responding disease is beneficial for pts. We repeated the analysis of Mass et al on pts enrolled in N9741, a study which established the superiority of FOLFOX over IFL and contained no biologic compound. Methods: For this retrospective analysis, pts were defined as ‘responders‘ or ‘nonresponders‘ according to whether criteria for complete or partial response (by RECIST -AVF2107g or WHO criteria -N9741) were either achieved (responders) or not achieved (nonresponders). PFS and OS were estimated from Kaplan-Meier curves; hazard ratios (HR) for progression and death in each subgroup were estimated by Cox regression. Results: In both trials, response was associated with superior outcome. However, statistically significant improvements in PFS and OS were observed in both responders and non-responders treated with either IFL + BV or FOLFOX versus IFL, and the magnitude of improvement was similar regardless of response ( Table ). Conclusions: Analysis of two large recent mCRC phase III trials clearly demonstrate that pts who do not achieve a response according to traditional criteria still have significant benefit from the superior regimen, with a similar magnitude of benefit for responders and non-responders, regardless if the regimen called for CT alone or included the antiangiogenic biologic BV. These data support the conclusion that PFS and the percentage of pts experiencing tumor control may more accurately reflect pt benefit than does response rate in phase III trials in mCRC. [Table: see text] [Table: see text]

Purpose In the phase III study AVF2107g, bevacizumab (BV) demonstrated a survival benefit when added to irinotecan, fluorouracil, and leucovorin (IFL) in first-line metastatic colorectal cancer (mCRC). In a parallel phase III study, Intergroup N9741, oxaliplatin plus fluorouracil and leucovorin (FOLFOX) also demonstrated a survival benefit compared with IFL. As these two superior therapies have differing mechanisms of action, we explored whether the improved survival associated with the superior therapy was dependent on tumor response. Patients and Methods For these retrospective, exploratory analyses, patients were defined as responders or nonresponders by whether complete or partial response was achieved with first-line therapy. Results Compared with IFL alone, BV plus IFL and FOLFOX each demonstrated statistically significant improvements in progression-free survival (PFS) and overall survival (OS) regardless of objective tumor response. BV-treated nonresponders had a hazard ratio (HR) of 0.63 (P = .0001) for PFS and 0.76 (P = .0188) for OS compared with IFL-treated nonresponders. FOLFOX-treated nonresponders had an HR of 0.75 (P = .0029) for PFS and 0.74 (P = .0030) for OS compared with IFL-treated nonresponders. Conclusion In both AVF2107g and N9741, objective response did not predict the magnitude of PFS or OS benefit from the superior therapy; nonresponders, despite a poorer prognosis than responders, achieved extended PFS and OS from BV plus IFL or FOLFOX compared with IFL. On the basis of these data, tumor response in metastatic colorectal cancer is not a necessary factor for a therapy to provide benefit to an individual patient.