Concerning, drugs most likely to cause neutropenia and justifying the prescription of G-CSF as primary prophylaxis are anthracyclines (78.6%; n: 55), followed by alkylating agents (57.1%; n: 40), taxanes (41.4%; n: 29), platinum salts (41.4%; n: 29) and antimetabolites (27.1%; n: 19). The gene discussed is CSF3; the disease is Decreased total neutrophil count.