PTEN and breast cancer: In a phase II trial that involved seven patients with recurrent and/or metastatic head and neck squamous cell carcinoma treated with everolimus without any molecular selection, a median PFS of 1.5 months was reported with no objective response.15 One patient with breast cancer (8%) with a PTEN loss and an activating PIK3CA mutation experienced an objective response that lasted 8 months in SHIVA01.