CDK4 and cancer: Retrospective cohort study of adult patients throughout the San Francisco Bay area treated at Stanford Hospital and clinics since 2008 receiving cyclin dependent kinase 4 or 6 (CDK4/6) inhibitors, poly(adenosine diphosphate-ribose) polymerase inhibitors, and specific drugs within tyrosine kinases inhibitor subgroups with an available estimated glomerular filtration rate (eGFR) from days 1 to 60 after drug start compared with propensity score–matched patients without cancer.