To treat a pituitary tumor with radiation, doctors may use a variety of techniques depending on the size and location of the tumor. Conventional radiation covers a wide area in and around the tumor and is usually given daily for several weeks.
In the show, Stannis Baratheon dies under the sword of Jamie Lannister, wielded by a woman to fulfill a promise to Catelyn Stark, to avenge the death of Renly Baratheon. You can state he died of internal complications.
The question is relevant given the end of the HBO seriesâ fifth season, which led viewers to believe â but did not actually show â that Stannis had been killed by a vengeful Brienne of Tarth. (One of the seriesâ directors later confirmed that Stephen Dillaneâs character was, indeed, dead.)