Real-world treatment patterns and survival outcomes in HER2-positive metastatic gastric cancer

Öz

Background and Aims: Despite the evolution in management of metastatic human epidermal growth factor receptor-2 gastric cancer over the past decade, challenges remain in accessing new therapies in some parts of the world. We aimed to describe real-world treatment patterns, attrition, and survival outcomes in patients with human epidermal growth factor receptor 2-positive metastatic gastric cancer. Materials and Methods: This retrospective cohort study included patients aged ≥ 18 years with human epidermal growth factor receptor 2-positive metastatic gastric cancer who received at least one line of systemic antineoplastic therapy between January 1, 2015, and December 30, 2024. The primary outcome of the study was to define treatment choices and attrition rates in real-world clinical practice. Secondary endpoints were progression-free survival across treatment lines and overall survival. Results: Thirty-nine patients were included; median age was 65.5 years (min - max, 24.2 - 82.9), and 74.4% were male. The most common first-line regimens were oxaliplatin + 5-fluorouracil plus trastuzumab (38.5%) and docetaxel + cisplatin + 5-fluorouracil plus trastuzumab (25.6%); 15.4% did not receive trastuzumab, and no patient received pembrolizumab as first-line treatment. Median first-line progression-free survival was 7.49 months (95% CI 5.56 - 9.42), and median overall survival was 16.53 months (95% CI 12.56 - 20.49). Overall, 68.4% of patients received second-line therapy, 41.0% received third-line therapy, and 10.3% proceeded to fourth-line treatment. Second-line treatment was predominantly irinotecan + 5-fluorouracil-based, while paclitaxel was the most frequent third-line regimen. Median progression-free survival was 3.35 months (95% CI 3.02 - 3.68) in the second line and 2.69 months (95% CI 2.28 - 3.10) in the third-line setting. Disease progression was the leading cause of treatment discontinuation across all lines. Conclusion: Human epidermal growth factor receptor-2-positive metastatic gastric cancer remains associated with poor survival and limited real-world access to novel agents. There is an ongoing need for more effective therapies and better implementation of new treatments in routine practice.

Anahtar Kelimeler

• Gastric cancer
• HER2
• trastuzumab

Kaynakça

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