Chemotherapy still contributes very little to the five year survival rate of solid cancers. Changing the strategy of how to treat solid cancers could change the success rate significantly. While cell death-inducing agents (so-called "chemotherapeutica") and combinations thereof are still the first line treatment in oncology, another strategy to achieve selective cancer cell death is to simultaneously deplete glutamine, pyruvate and oxaloacetate in vivo with or without using "chemotherapeutica".While it is known for many years that tumor cells are addicted to glucose, addiction to glutamine is also known for quite a while but there is little effort to use glutamine-addiction for treating cancers. This is only a basic communication illustrating some aspects of glutamine-metabolism and also of chemotherapeutic options of how to interfere with it. However, it may interest more cancer-treating doctors. Maybe it will improve the success rate of treating solid tumors.