The role of noise in the tumor dynamics under chemotherapy treatment Irina Bashkirtseva, Lev Ryashko, Jorge Duarte, Jesús M. Seoane and Miguel A. F. Sanjuan Eur. Phys. J. Plus, 136 11 (2021) 1123 Published online: 09 November 2021 DOI: 10.1140/epjp/s13360-021-02061-z