I. To evaluate investigator-assessed progression-free survival (IA-PFS) and overall survival (OS) of cell cycle gene alteration-positive patients treated with palbociclib. (Phase II) II. To evaluate the duration of response (DoR) among cell cycle gene alteration positive patients treated with palbociclib who achieve a complete response (CR) or partial response (PR) (confirmed and unconfirmed) by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. (Phase II) III. To evaluate the frequency and severity of toxicities associated with palbociclib. (Phase II)