Celebrity Cancer Forces Maura Tierney Off New Show The former ER actress formally withdraws from NBC's Parenthood By Stephen M. Silverman Published on September 11, 2009 08:30AM EDT Share Tweet Pin Email Photo: Dan Steinberg/AP Having revealed in July she was undergoing surgery for removal of a breast tumor, Maura Tierney has now withdrawn from her upcoming series Parenthood, say trade reports. The star’s spokeswoman told the Hollywood Reporter that the former ER actress, 44, is “deeply disappointed” not to be participating in the NBC show, and that “Ms. Tierney and her doctors remain confident that the outcome of her treatments will be positive.” FIRST LOOK: Edie Falco & Cynthia Nixon’s Stand Up to Cancer PSA Tierney’s operation had already pushed back the series’ original fall debut date, and Parenthood will now be offered mid-season. In a network’s statement, NBC said, “While we are saddened that Maura Tierney won’t be able to continue in her current role in Parenthood, our main concern is for her quick and full recovery. Our thoughts and best wishes are with her.” Through her spokesperson, Tierney thanked the executive producer and NBC “for their patience and support.” Take our poll: Who should replace Maura Tierney on Parenthood?