Selina Wang reports on former President Joe Biden's prostate cancer diagnosis days after his office says he recently began experiencing symptoms; Medical correspondent Dr. Darien Sutton on what a Gleason score of 9 and a metastasis to the bone means at this stage of life; Rhiannon Ally has the latest on a Mexican navy tall ship that slammed into the Brooklyn Bridge killing at least two people and left nearly 2 dozen others injured; Jaclyn Lee reports on the suspect who police say is behind an explosion at a fertility clinic in Palms Springs California, what officials are saying about a motive; and more on tonight's broadcast of World News Tonight.