Coburn, who underwent surgery Monday in Tulsa, is "expected to make a full recovery and return to his full-time duties later this month," spokesman John Hart said, The Oklahoman reported.
Coburn, a 63-year-old physician, had survived cancer twice before the latest surgery -- a malignant melanoma in 1975 and colon cancer in 2003.
He had a benign tumor removed from his pituitary gland in 2007.
Coburn, who won a second six-year term last year, has said he will not run again in 2016.
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