Turkiye Klinikleri Journal of Medical Sciences

.: ORIGINAL RESEARCH
Lung Cancer Survival Analysis: A Comparative Evaluation of Cox Proportional Hazards and Accelerated Failure Time Models: An Analytical Study
Akciğer Kanseri Sağkalım Analizi: Cox Orantılı Tehlikeler ve Hızlandırılmış Başarısızlık Süresi Modellerinin Karşılaştırmalı Değerlendirmesi: Analitik Çalışma
Gülcan GENCERa
aAfyonkarahisar Health Sciences University Faculty of Medicine, Department of Biostatistics, Afyonkarahisar, Türkiye
Turkiye Klinikleri J Med Sci. 2025;45(1):8-16
doi: 10.5336/medsci.2024-105382
Article Language: EN
Full Text
ABSTRACT
 Objective: This study aims to evaluate and compare the Cox Proportional Hazards (PH) model and Accelerated Failure Time (AFT) models in the survival analysis of lung cancer patients. The analysis focuses on survival times across different cell types, prior therapies, and treatment groups. Material and Methods: The study was conducted using a dataset containing survival times, censoring indicators, and variables such as cell type, prior therapy, and treatment group. The Cox PH model and 3 AFT models (Weibull, Log-Normal, Log-Logistic) were applied. While the Cox PH model does not assume a specific distribution for survival times, AFT models assume parametric distributions. Model performance was evaluated using the Akaike Information Criterion (AIC). Results: The Smallcell type was identified as the most aggressive cancer type, with the lowest survival probability. AFT models, particularly the Weibull AFT model, provided a better fit to the data than the Cox PH model, as indicated by lower AIC values. Prior therapy was associated with lower survival probabilities, suggesting higher risk among these patients. The standard treatment group showed slightly better survival over time. Conclusion: This study highlights the importance of selecting an appropriate survival analysis model based on the characteristics of lung cancer data. While the Cox PH model offers flexibility, the Weibull AFT model provided better insights and fit. These findings emphasize the critical role of model selection in accurately understanding and predicting patient outcomes in lung cancer survival analysis.

Keywords: Lung cancer; survival analysis; Cox proportional hazards model; accelerated failure time model
ÖZET
 Amaç: Bu çalışma, akciğer kanseri hastalarının sağkalım analizinde Cox Orantılı Tehlikeler [Proportional Hazards (PH)] modeli ile Hızlandırılmış Başarısızlık Süresi [Accelerated Failure Time (AFT)] modellerini değerlendirmeyi ve karşılaştırmayı amaçlamaktadır. Farklı hücre tipleri, önceki tedavi ve tedavi grupları arasındaki sağkalım süreleri incelenmiştir. Gereç ve Yöntemler: Analiz, sağkalım süreleri, sansür göstergeleri ve hücre tipi, önceki tedavi ve tedavi grubu gibi değişkenleri içeren bir veri seti ile gerçekleştirilmiştir. Veri setine Cox PH modeli ve 3 AFT modeli (Weibull, Log-Normal, Log-Lojistik) uygulanmıştır. Cox PH modeli, belirli bir dağılım varsaymazken, AFT modelleri parametrik dağılımlar varsayar. Model performansı Akaike Bilgi Kriteri [Akaike Information Criterion (AIC)] ile değerlendirilmiştir. Bulgular: Küçük hücre tipi en düşük sağkalım olasılığı ile daha agresif bir kanser tipi olarak belirlenmiştir. AFT modelleri, özellikle Weibull AFT modeli, daha düşük AIC değerleri ile Cox PH modeline kıyasla daha iyi uyum sağlamıştır. Önceki tedavi, daha düşük sağkalım olasılıkları ile ilişkili bulunmuş, bu da daha yüksek risk altında olduklarını göstermiştir. Standart tedavi grubu ise zamanla biraz daha iyi performans göstermiştir. Sonuç: Çalışma, akciğer kanseri verilerinin özelliklerine uygun sağkalım analiz modelinin seçilmesinin önemini vurgulamaktadır. Cox PH modeli esneklik sunarken, özellikle Weibull AFT modeli, daha iyi içgörüler ve uyum sağlamıştır. Bu bulgular, model seçiminin hasta sonuçlarını doğru anlamak ve tahmin etmek açısından önemini ortaya koymaktadır.

Anahtar Kelimeler: Akciğer kanseri; sağkalım analizi; Cox orantılı tehlikeler modeli; hızlandırılmış başarısızlık süresi modeli
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