Final answer:
Carcinomas usually spread via the lymphatic system and sarcomas via the bloodstream, but exceptions like renal cell and hepatocellular carcinomas often metastasize through blood vessels.
Step-by-step explanation:
Carcinomas spread primarily via the lymphatic system, while sarcomas typically spread through the bloodstream. However, there are exceptions to the general rule of how carcinomas spread. For instance, some carcinoma types can metastasize via blood vessels instead of the lymphatic system.
Metastasis occurs when cancer cells break away from the primary tumor and spread to other parts of the body. The method of spread can greatly affect the prognosis and treatment approach. Both carcinomas and sarcomas can metastasize to distant organs such as the brain, lungs, bones, and liver, although the pathways they take may differ.