ESR1 and breast cancer: In TELEPIK trial, patients with advanced estrogen-receptor (ER) positive /HER2-negative breast cancer eligible for a combination of alpelisib and fulvestrant (patients with activating somatic PIK3CA-mutation fulfilling eligibility criteria similar to SOLAR-1 trial5) were eligible to be included and be followed remotely through a dedicated cloud-based, patient-centric mobile platform provided by a vendor.