HARRISBURG -- It's been a month since Lt. Gov. Catherine Baker Knoll was diagnosed with cancer, but she waited until yesterday to go public with the news because she wanted to tell her family first, her spokesman said.

"She understands there is an obligation on the public side" but she wanted time to tell her eight siblings and numerous nieces and nephews, with whom she is close, spokesman Salvatore Sirabella said today.

It was not immediately clear when she notified Gov. Ed Rendell of her condition, which she has described as a neuroendocrine illness.

In a statement today, Mr. Rendell said he and his wife Midge are saddened by the news "but we are not surprised that she is fighting back and continuing to serve the citizens of our commonwealth. To know Catherine is to understand that she is a person of incredible strength and determination."

Mrs. Knoll, 77, has been working from her home near Fort Indiantown Gap since she learned of the diagnosis. Mr. Sirabella said it is not clear when she will return to the Capitol, although she plans to continue working from home during her cancer treatment.

If she were to step down, Senate President Pro Tem Joe Scarnati, R-Jefferson, would become lieutenant governor, creating an unusual dynamic of having the state's top government officials from different parties. In Pennsylvania, the governor and lieutenant governor run on the same ticket.

Mrs. Knoll, a McKees Rocks native, took office in 2003 as the state's first female lieutenant governor.

More details in tomorrow's Pittsburgh Post-Gazette.