An individualized bacterial treatment of cancer is provided. The treatment includes a strain of bacteria modified by in-vivo passage through tumor grafts in experimental animals, where the modified strain exhibits enhanced cancer cell-targeting of a specific malignancy arising in a unique individual to the corresponding parent strain of bacteria. The treatment uses this modified strain for the treatment human solid-tumor malignancies by inoculating an individual with a quantity of the strain and repeating inoculations at periodic intervals where repeated inoculations tend to progressively eliminate the solid tumor malignancy in the individual.
