In his letter to Idomeneus, Epicurus calls his last day "blessed" (makarion). And "But the cheerfulness (χαῖρον khairon) of my mind, which arises from the recollection of all our philosophical contemplations, counterbalances all these afflictions." (Yonge's translation with amending "our" instead of "my philosopical...") khairon is a form of the word used for the kinetic pleasure of "joy" khara. And Epicurus doesn't say the "joy" outweighs or conquers the pain of his condition. The word used is Ἀντιπαρατάσσομαι (antiparatassomai) which conveys "holding one's ground against, and in drawing up troops in battle order, side by side, ready to do battle against an enemy." He can do battle with the physical pain with the kinetic "joy" he can experience.
I just wanted to emphasize that the pain never goes away. Epicurus experiences every bit of the pain, but he can do battle with it by recollections of the good times he had and the satisfaction of how he lived his life.
