Gripped by a horrific cancer nightmare, Barbra Streisand secretly underwent surgery on her colon in early December, The ENQUIRER has learned exclusively.

Despite her near-paralyzing fear of operations, the 62-year-old Oscar winner had part of her colon removed months after results of a routine screening revealed the presence of growths called polyps, which can be cancerous, say sources.

The operation was originally scheduled for early September – but the terrified singer panicked and called it off only hours before it was to take place, The ENQUIRER discovered.

The multi-talented entertainer finally mustered every bit of her courage and went ahead with the surgery early in the first week of December at Cedars-Sinai Medical Center in Los Angeles.

“Shortly before the operation, Barbra was shaking and saying, ‘It can’t be cancer, it just can’t,'” revealed an insider.

“She is deathly afraid of surgery and often harps on how much she hates the thought of being unconscious while surgeons root around inside her body.

“Even though she always has the best care and doctors available, Barbra is almost inconsolable about any type of operating-room procedure.

“Although the calmest environment possible was provided, she was wildly emotional before the surgery. She told pals, ‘I don’t want to die!'”

In The ENQUIRER now on sale., you’ll read all the dramatic details — including the reaction of Barbra’s devoted husband James Brolin, why she eventually agreed to the operation — and the amazing technique that got her out of the hospital only about 24 hours after the surgery.