Actor Patrick Dempsey (photo), the Maine native who plays the neurosurgeon known as Dr. McDreamy on ABC’s medical drama “Grey’s Anatomy,” visited Central Maine Medical Center in Lewiston to lend support to the new cancer center that bears his name. The Patrick Dempsey Center for Cancer Hope & Healing will open March 31, offering education and support programs for cancer patients and their families. The 42-year-old Dempsey, whose mother was successfully treated at the hospital for ovarian cancer, provided a seed grant for the new center. He also plans to take part in its public education campaign about cancer prevention and detection. Dempsey was born in Lewiston and grew up in the Turner-Buckfield area.