Implementation of pharmacogenetics (PGx) in the clinical practice of cancer therapy is one of the goals for a precision medicine. For some anticancer drugs (fluoropyrimidines and irinotecan) precise recommendations by regulatory agencies are available. However, in the future, implementation of PGx in clinical practice should also consider the anticancer drugs without available pharmacogenetic guidelines and the increasingly important role of rare PGx variants. To overcome barriers to PGx implementation we need to focus on pharmacogenetic test clinical utility by adopting a panel-based approach and sensitize both physician and patients to the therapeutic value of pharmacogenetic tests.