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This review seeks to highlight and celebrate Professor Tomizo Yoshida’s famous work on “Establishment and characterization of a rat ascites sarcoma, later named “Yoshida ascites sarcoma”. Considering the tremendous contribution of this ascites tumor system to the subsequent promotion of research on cancer biology and cancer chemotherapy, his paper should be regarded as a monumental one in the cancer field. The research was carried out during 1943 and the results were submitted to this Journal in October 1944, when Japan was approaching a debilitating defeat in World War II in August 1945. In 1947, when “Research on Ascites sarcoma” was first comprehensively introduced to researchers in a special lecture at the Annual Meeting of the Japanese Society of Pathology, the whole audience was deeply impressed and was encouraged to resume scientific activity in Japan.

Chemotherapy, a vital cancer treatment, operates by delivering drugs to target and eliminate cancer cells in the patient body. Mathematical models like the log-kill, Norton-Simon, and $E_{\max }$ hypotheses describe the growth/shrinking of the cancerous tumor due to the interaction and administration of the drugs with the tumor. This paper proposes a robust control approach based on artificial time-delayed theory to track the desired rate of change in tumor volume under model uncertainties and disturbances. The proposed algorithm relaxes the assumption on a priori knowledge of disturbance bound and its derivative. Unlike traditional methods, the control structure is simple, and the total disturbance is estimated by analyzing the previous input and output of the feedback state and control variables. Thus, robustness is ensured without relying on high-frequency switching or high gain. The stability analysis of the proposed scheme is investigated based on the Lyapunov theory. Moreover, extensive simulation results with comparative analysis affirm the efficacy of the proposed approach.