A Mathematical Model for Cachexia Index in Advanced Non-Small-Cell Lung Cancer Patients by using Weibull Distribution

In this paper, we introduce the Weibull distribution. Weibul cumulative distribution function determined the values for both the shape and scale parameters, in order to accurately predict the cancer level for the location. Cancer cachexia affects many advanced non-small-cell lung cancer (NSCLC) patients. Cachexia index (CXI) was developed to assess the degree of cachexia in these patients. Abdominal computed tomography scans done within 1 month of diagnosis were reviewed to estimate skeletal muscle area (SMA) and skeletal muscle index (SMI) at the L3 level. CXI was developed as follows: where SMI is the skeletal muscle index, Alb is the serum albumin, and NLR is the neutrophil-to-lymphocyte ratio. Progression-free survival (PFS) and overall survival (OS) were estimated. Multivariate Cox regression was used to perform survival analysis in order to estimate the effects of various factors. The CXI is a novel index for estimating cachexia that also correlates with prognosis in both men and women with advanced NSCLC.