Former “ER” actress Maura Tierney has found a tumor in her breast, according to a new report from Us magazine.

Tierney, 44, has pushed back the premiere of her new NBC series “Parenthood” in order to undergo an emergency surgery.

"In an effort to guard my privacy, it seems that the wording of NBC's press release has unfortunately caused some confusion and undue alarm about my health. I have discovered a tumor in my breast which requires surgery," the actress said in a statement.

She said she will not know the severity of her condition until after surgery, but assured fans that doctors are optimistic about her “treatable condition.”

"I'm very optimistic as to the outcome and want to thank everyone who has sent positive thoughts and support. I look forward to going back to work soon,” she added.

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