The rocker, recovering from breast surgery, reschedules several shows

The show is about to go on for Sheryl Crow, who is recuperating from successful breast-cancer surgery last month.

The 44-year-old rocker, who postponed March and April tour dates once her medical condition was diagnosed, will open June 12 at the Murat Theater in Indianapolis, she has announced. Concerts will follow in Illinois, Minnesota, Iowa, Texas, Tennessee, Alabama and Georgia.

For the June shows, Jack Ingram will be the opener. Crow will play July 4-5 in Orillia, Ontario, and July 7-8, with the Dave Matthews Band, at Boston’s Fenway Park.

According to her Web site, Crow intends to reschedule additional shows in Omaha, Nebraska; Newark, New Jersey; Manchester, New Hampshire; Norfolk, Virginia; Erie, Pennsylvania; and Verona, New York. However, shows previously scheduled for Houston, St. Louis and Atlantic City, New Jersey cannot be accommodated in her lineup at this time.

Also on her Web site, Crow termed her surgery “minimally invasive” and said she would undergo radiation treatment as a precaution. “I am joining the more than 200,000 women who will be diagnosed with breast cancer this year,” she says. “We are a testament to the importance of early detection and new treatments.”

When Crow’s condition was announced late last month, her former fianc , Lance Armstrong, 34, said in a statement to PEOPLE: “I was devastated to hear this news. Once again I’m reminded of just how pervasive this illness is as it has now touched someone I love deeply.”

He added, “Based on my contact in recent days with Sheryl, her doctor, and her family, I am confident that she will have a full and complete recovery and the world will be a better place for it. And to all of her fans and friends out there, please keep Sheryl in your thoughts and prayers yet know that I have never known a stronger woman in my life.”