Estimating and determining the effect of a therapy on tumor dynamics by means of a modified Gompertz diffusion

Giuseppina Albano1, Virginia Giorno2, Patricia Román-Román3

  • 1Dip. di Scienze Economiche e Statistiche, Università di Salerno, Italy.

Insights

This study models tumor growth using a modified Gompertz diffusion process, estimating therapy effects on cell growth and death. A new method determines therapy impact using relative entropy, applicable to combined treatments and single-agent analysis.

Area of Science:

  • Mathematical Biology
  • Biostatistics
  • Pharmacodynamics

Background:

  • Tumor growth dynamics are complex and influenced by various factors, including therapeutic interventions.
  • Modeling tumor progression requires understanding the interplay between cell proliferation and death rates.
  • Existing models may not fully capture the nuanced effects of combined therapies on tumor dynamics.

Purpose of the Study:

  • To develop a methodology for estimating time-dependent therapy effects on tumor dynamics using a modified Gompertz diffusion process.
  • To enable the estimation of individual therapy functions when combined treatment data is available.
  • To determine the predominant in vivo effect (growth or death) of a single therapeutic agent.

Main Methods:

  • Utilized a modified Gompertz diffusion process incorporating non-homogeneous terms for therapy effects.
  • Proposed a method to estimate time-dependent functions representing therapy impact on birth and death parameters.
  • Employed Kullback-Leibler divergence (relative entropy) as a criterion for analyzing therapy effects.

Main Results:

  • Successfully developed a methodology to estimate therapy-induced changes in tumor growth and death rates.
  • Demonstrated the ability to infer individual therapy effects from data of combined treatments or control groups.
  • The Kullback-Leibler divergence criterion proved effective in distinguishing therapy impacts.

Conclusions:

  • The proposed methodology offers a robust framework for analyzing tumor dynamics under therapeutic intervention.
  • This approach facilitates the characterization of single-agent therapy effects in vivo.
  • The study provides valuable tools for pharmacodynamic modeling and treatment optimization.

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