The three-time Ballon d'Or winner was told of his illness in October.
The 68-year-old won three consecutive European Cups with Ajax as a player and led Barcelona to their first European Cup win in 1992 as manager.
"The results have been very positive," he said. "Thanks to the excellent work of the doctors, the affection of the people and my positive mentality."
"Right now, I have the feeling that I am 2-0 up in the first half of a match that has not finished yet," he added. "But I am sure I will end up winning."
Cruyff helped his country reach the World Cup final in 1974, where they lost to West Germany.
He also led Barcelona to the the European Cup Winners' Cup in 1989.
Barcelona also won four consecutive La Liga titles from 1990-91 to 1993-94 under his guidance.
Widely regarded as one of the greatest players of all time, Cruyff had double heart bypass surgery in 1991.
Having been a smoker, he gave up immediately after the operation and took to sucking lollipops in the dugout.
He featured in a Catalan health department advert, saying: "Football has given me everything in life, tobacco almost took it all away."
Netherlands great and former Barcelona boss Johan Cruyff says he is "2-0 up in a match" against lung cancer.