Beyoncé and Solange Knowles' father, producer/manager Mathew Knowles, is speaking out about his male breast cancer diagnosis and treatment and his desire to use his public megaphone to speak out and, hopefully, save lives.Knowles, 68, spoke to People magazine about initially brushing off a telltale sign, then realizing that something was wrong in July 2019, when he saw a pinprick-sized red dot on his shirt."I was in disbelief," said Knowles, who knew to take care of his health after years of