Study to Determine the Safety and Efficacy of Ribociclib in Combination With Hormone Therapy and Hypofractionated Radiotherapy in Breast Cancer, With Positive Hormone Receptors and Negative HER2 Status, in Newly Diagnosed, Not Immediately Operable Elderly Patient (CALHYS)

"600mg per day during registration phase (3 cycles); de-escalation phase (600 to 200mg per day associated to radiotherapy) during 3 other cycles; maintenance phase until 24 months of treatment in total (600mg per day).~All over th etimme, hormonotherapy is received in concomitance"