The murder of the 7 nurses said at the end of the episode is a reference to Richard Speck; a mass murderer who tortured 8 nurses and killed 7 nurses in 1966.
Mistletoe extract injections are a real, but controversial, cancer treatment in the realm of "complementary medicine." Mistletoe was proposed as a cure cancer because "like cures like" - mistletoe is a parasitic plant that can kill its host, the way cancer can take over a body.