Most Rev Michael Curry opted to undergo surgery next Tuesday for the disease, which is diagnosed 47,000 times in UK men each year.
In an open letter, the Presiding Bishop of The Episcopal Church said: "I am happy to say that the prognosis looks very good and quite positive."
Announcing that the tumour was discovered during his annual physical examination a few months ago, the 65-year-old said the procedure will seek to remove his prostate gland.
Bishop Curry said he anticipates being in hospital for at least one day which will be followed by recuperation at home for between four and six weeks.
He added: "I have spoken with several others who have gone through this, and who have offered both encouragement and helpful advice.
"I plan to resume my duties in early September and I do not anticipate any significant changes in my commitments.
"I am very blessed with a wonderful family, a first-rate medical team, a great staff, dear colleagues and friends, a calling to which I have given my life, and above all a good, great and loving God in whose hands we always remain.
"So, do say a prayer. And know that I look forward to being back at my post in September."
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