The Short Version
The claim is broadly supported by the biomedical literature. Cancer-associated Warburg metabolism does produce measurable signals tied to increased glucose uptake and lactate production, and these can inform diagnostic strategies, especially FDG-PET. The main caveats are that FDG-PET tracks a glucose-analog tracer rather than direct glucose levels, lactate is less uniformly established in routine practice, and not all cancers show the same metabolic pattern.