We also note, however, that this code has been employed in several single technology appraisals (STAs) and evidence review group’s (ERG) reports to cost chemotherapy-related febrile neutropenia among adults with HER2-negative metastatic breast cancer, adults with chronic lymphocytic leukemia, adults with metastatic prostate cancer, and adults with squamous cell carcinoma of the head and neck, respectively [15-18]. This evidence concerns the gene ERBB2 and metastatic prostate carcinoma.