Toward precision medicine in inflammatory breast cancer

Inflammatory breast cancer (IBC) is an aggressive, although infrequent form of invasive breast cancer. Despite some advances in systemic treatment, even in the early setting, with combined-modality approach being the current recommended standard of care, the prognosis of IBC still remains unfavorable and has not significantly improved over time. Thus, a better understanding of the biology of IBC is eagerly awaited in order to identify possible targets for new drug development. This paper aims to provide an overview on recent data on the molecular and biological features of IBC and on possible targetable pathways. Molecular subtypes of IBC, similarly to other forms of breast cancer, have both therapeutic and prognostic implications. Moreover, few activated pathways have been described in IBC, including angiogenesis, epidermal growth factor receptor (EGFR), Janus kinase/signal transducer of activation (JAK/STAT) signaling and phosphoinositide 3-kinase/Akt/mTOR (PI3K/AKT/mTOR) pathways. However, when tested in clinical trials, agents targeting these pathways have provided only small benefit. Several clinical trials are currently ongoing investigating combination of standard chemotherapeutics, new targeted agents and immunotherapy. Moreover, tumor microenvironment (TME) is likely to play a central role in the disease; targeting the components of the tumor stroma may represent an interesting therapeutic strategy.