The Staten Island cancer doctor who treated George Harrison is under investigation by the state Health Department for publicly talking about the ex-Beatle's last days, The Post has learned.

The investigation began after Harrison's estate complained that Dr. Gil Lederman of Staten Island University Hospital violated confidentiality rules by giving interviews about the late Beatle, sources told The Post. 

A frail Harrison  who fiercely guarded his privacy — checked into the hospital in October. 

Lederman offers an innovative treatment called fractionated sterotactic radiosurgery — which attacks tumors with high doses of pinpoint radiation. 

Following Harrison's death Nov. 29, Lederman was quoted in TV and newspaper interviews as saying the former Beatle did not fear death and was writing and recording songs until the end. 

Lederman had told The Post that after checking out of the hospital, Harrison stayed at a Staten Island house for two weeks while undergoing outpatient treatment. 

He also recounted how the rock legend, whom he described as "quiet and dignified," played him some new songs and gave the doctor's 13-year-old son a personal guitar lesson. 

"He believed death was a part of life," Lederman said at the time. "He was not fearful of death." 

Although Lederman seemingly stayed clear of talking about Harrison's specific medical condition, that may not matter. 

Under law, the "revealing of personally identifiable facts, data, or information obtained in a professional capacity without the prior consent of the patient . . . is defined as misconduct." 

Robert Chapman, a lawyer for the Harrison estate, had no comment on the probe. The Health Department would not confirm or deny an investigation, but an official said doctors are bound by confidentiality regulations even after a patient's death. 

If found guilty, Lederman, who's never been sanctioned by the state, could face anything from censure and reprimand to a license suspension or revocation. Lederman did not return calls for comment.

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