Notice how all these studies can only say "should", "could" and "may" but not a single study can show that cannabis "Does" cause cancer. To the contrary, many studies show that cannabis shrinks tumors. Tons of proof that prohibition of cannabis kills and destroys the lives of tens of thousands of people every year. The FDA, DEA, pharmaceutical companies, the prison industrial complex and politicians all profit from keeping you mis-informed about cannabis. Countless lives will continue to be ruined until we wake up and end prohibition.