Molecular Features Predicting Response/Resistance to Trastuzumab in Metastatic Breast Cancer Patients

Observational Study Assessing Molecular Features Predicting Response/Resistance to Trastuzumab in Metastatic Breast Cancer Patients

Aim of the study is to assess the impact on response to Herceptin-based therapy in patients with advanced breast cancer. Tumor specimens from primary breast cancer will be analized for several biological factors potentially involved in Herceptin sensitivity.

Tests that will be performed include: FISH analyses of EGFR, HER-2, HER-3, C-MYC, PTEN, MET, IGFR-1. Immunofluorecence of P95HER2. Mutation analyses of EGFR, HER-2, MET, C-MYC, PTEN, KRAS, PIK3CA, IGFR-1. Immunohistochemistry of the same biomarkers.

Inclusion Criteria:

• Hystological diagnosis of breast cancer
• Availability of tumor tissue
• Availability to assess the response to Trastuzumab according to RECIST criteria
• Availability of clinical data

Exclusion Criteria:

• Unavailability of tumor tissue
• Impossibility to assess the response to Trastuzumab according to RECIST criteria