Patients that will be considered eligible for the study will undergo downstaging procedures according their stage of disease and to Center's policies. Length and intensity of downstaging will be center specific and not centrally pre-determined, but should be inferior to 18 months. Downstaging procedures will be stopped when, according to the Investigators' judgement, the best possible tumor response has been achieved: at this timepoint a radiological evaluation of tumor response according to modified RECIST (mRECIST) criteria will be performed. Patients that have achieved a Complete or Partial Response (PR or CR) will proceed to Bridging Phase, while those with a Stable or Progressive disease (SD or PD) will drop-out from the study.