Identification on surrogating overall survival with progression-free survival of first-line immunochemotherapy in advanced esophageal squamous cell carcinoma-an exploration of surrogate endpoint

Comparison of Hepatic Function and Chemotherapy-Induced Side Effects Between Pegylated Liposomal Doxorubicin (PLD), Topotecan (TOPO), and Gemcitabine in Platinum-Resistant Ovarian Cancer (PROC)

Background/Objectives: Platinum-resistant ovarian cancer (PROC) is a major therapeutic challenge, as it responds poorly to standard platinum-based treatment, has limited treatment options, and offers a generally unfavorable prognosis. Chemotherapeutic agents like pegylated liposomal doxorubicin (PLD), topotecan (TOPO), and gemcitabine (GEM) are used for this setting, but with varying efficacy and toxicity profiles, leading to an increasing need to understand the optimal balance between treatment effectiveness and tolerability for improving patient outcomes. This study evaluates the efficacy and side effects of PLD, TOPO, and GEM, focusing on progression-free survival (PFS), overall survival (OS), and safety profiles. Methods: We conducted a retrospective observational study that included 856 PROC patients treated with PLD (n = 383), TOPO (n = 352), or GEM (n = 121) at the OncoHelp Oncology Center from January 2018 to December 2023. Inclusion criteria encompass diagnosis, prior platinum therapy, and Eastern Cooperative Oncology Group (ECOG) status (0-2). Treatment protocols followed standard dosing, with adjustments for toxicity. Primary endpoints included PFS and OS, with safety assessed by incidence of grade 3 and 4 toxicities per CTCAE v5.0. Kaplan-Meier analysis and Cox regression were used to compare survival, and statistical significance was set at p < 0.05. Results: TOPO showed higher toxicity than PLD and GEM, including liver damage, hematological and non-hematological side effects, while PLD induced more skin toxicity. In terms of survival, minor differences were seen between the three chemotherapeutic agents, with a slight advantage for PLD for better disease control. Conclusions: Given the comparable results in OS across the regimens, treatment decisions should be based on other factors such as patient tolerance and quality of life.

Mechanistic Learning for Predicting Survival Outcomes in Head and Neck Squamous Cell Carcinoma

We employed a mechanistic learning approach, integrating on-treatment tumor kinetics (TK) modeling with various machine learning (ML) models to address the challenge of predicting post-progression survival (PPS)-the duration from the time of documented disease progression to death-and overall survival (OS) in Head and Neck Squamous Cell Carcinoma (HNSCC). We compared the predictive power of model-derived TK parameters versus RECIST and assessed the efficacy of nine TK-OS ML models against conventional survival models. Data from 526 advanced HNSCC patients treated with chemotherapy and cetuximab in the TPExtreme trial were analyzed using a double-exponential model. TK parameters from the first line and maintenance (TKL1) or after four cycles (TK4) were used to predict PPS and post-cycle 4 OS (OS4), combined with 12 baseline parameters. While ML algorithms underperformed compared to the Cox model for PPS, a random survival forest was superior for OS prediction using TK4 and surpassed RECIST-based metrics. This model demonstrated unbiased OS4 prediction, suggesting its potential for improving HNSCC treatment evaluation. Trial Registration: ClinicalTrials.gov identifier: NCT02268695.

Recurrence-free survival as a surrogate endpoint for overall survival after neoadjuvant chemotherapy and surgery for oesophageal squamous cell carcinoma

BACKGROUND

Overall survival is considered as one of the most important endpoints of treatment efficacy but often requires long follow-up. This study aimed to determine the validity of recurrence-free survival as a surrogate endpoint for overall survival in patients with surgically resectable advanced oesophageal squamous cell carcinoma (OSCC).

METHODS

Patients with OSCC who received neoadjuvant cisplatin and 5-fluorouracil, or docetaxel, cisplatin and 5-fluorouracil, at 58 Japanese oesophageal centres certified by the Japan Esophageal Society were reviewed retrospectively. The correlation between recurrence-free and overall survival was assessed using Kendall's τ.

RESULTS

The study included 3154 patients. The 5-year overall and recurrence-free survival rates were 56.6 and 47.7% respectively. The primary analysis revealed a strong correlation between recurrence-free and overall survival (Kendall's τ 0.797, 95% c.i. 0.782 to 0.812) at the individual level. Subgroup analysis showed a positive relationship between a more favourable pathological response to neoadjuvant chemotherapy and a higher τ value. In the meta-regression model, the adjusted R2 value at the institutional level was 100 (95% c.i. 40.2 to 100)%. The surrogate threshold effect was 0.703.

CONCLUSION

There was a strong correlation between recurrence-free and overall survival in patients with surgically resectable OSCC who underwent neoadjuvant chemotherapy, and this was more pronounced in patients with a better response to neoadjuvant chemotherapy.