Evolution of malignant tumors as neoorgan and predictions of future scenarios resulting from inappropriate treatment.

Malignant tumors have long been viewed as uncontrolled cell proliferation driven by somatic mutations. However, emerging multi-omics and microenvironment evidence challenges this paradigm. Advanced tumors transcend cellular abnormality to form a "neoorgan" - a complex tissue ecosystem with multicellular coordination, functional autonomy, metabolic symbiosis, neural integration, and evolutionary potential. Genomic instability generates lineage-specific karyotypes; tumors reactivate ancient gene modules from primitive multicellular organisms; they actively remodel immune function via mitochondrial transfer; and they establish functional connections with the nervous system. Based on this evolutionary trajectory, we propose testable predictions: tumors may progress from a parasitic neoorgan toward an independent species, as exemplified by naturally occurring transmissible tumors and the "tumor-derived animal" hypothesis. Recognizing cancer as an evolutionary entity striving for independence - rather than a mere genetic malfunction - demands a fundamental shift in therapeutic strategy. Instead of solely cytotoxic "killing", rational approaches may aim to reintegrate the tumor into host regulatory networks or guide its evolution toward self-destruction. This framework expands tumor biology and challenges conventional boundaries between disease, life, and species.