- Presence of at least one measurable lesion according to RECIST 1.0, defined as a lesion that can be accurately measured in at least one dimension (longest diameter) as ≥ 20 mm with conventional techniques (conventional CT or MRI scan) or as ≥ 10 mm with spiral CT scan. Lesions in previously irradiated areas can be considered measurable only if they have demonstrated clear evidence of progression since the radiotherapy.