Tierney drops series because of cancer diagnosis

Maura Tierney, who is probably best-known for her ten-year stint as nurse Abby Lockhart on the NBC series "ER", is dropping out of a new series she had begun filming because of recently being diagnosed with and beginning treatment for breast cancer.

In the new NBC series "Parenthood," Tierney was cast as a single mother returning home to her parents. The show is based on the 1989 movie of the same title starring Steve Martin. The series had pushed back the show's fall start date to accommodate for Tierney's removal of a tumor earlier this summer. However, on Thursday, the actress announced that she would have to leave the show in order to continue treatment for the cancer.

Her role on the show is going to be recast, but NBC expressed sadness and concern for the actress. Tierney is optimistic about her treatment and recovery, and says her prognosis is good.