Recomendaciones para la determinación de HER2 en cáncer de mama. Consenso Nacional de la Sociedad Española de Anatomía Patológica ( SEAP ) y de la Sociedad Española de Oncología Médica ( SEOM )

Breast cancers with HER2 alterations are critical to identify because such tumors require unique treatment, including the use of targeted therapies. HER2 alterations at the DNA (amplification) and protein (overexpression) level usually occur in concert, and both in situ hybridization and immunohistochemistry can be accurate methods to assess these alterations. However, recent studies including those conducted by the Association for Quality Assessment of the Spanish Society of Pathology and the experience of several national reference centres for HER2 testing have suggested that serious reproducibility issues exist with both techniques. To address this, a joint committee of both the Spanish Society of Pathology and the Spanish Society of Medical Oncology has met to review guidelines for HER2 testing. Consensus recommendation are based not only on panellist’s experience but also in those consensus guidelines previously reported in several countries, such as United Stated, United Kingdom and Canada. These guidelines include minimal requirements that Pathology Department must meet in order to guarantee appropriate HER2 testing in breast cancer. Pathology laboratories that do not meet these standards must put effort to reach them and, in the meantime, send clinical cases to reference centres.