6. Patient undergoes at baseline new lymphnode or other pathologic tissue biopsy for confirmation of diagnosis and biologic studies; bone marrow biopsy is not adequate for this purpose and should be performed only for staging. Patients with primary refractoriness, not eligible for intensive salvage therapy including ASCT, who performed a previous biopsy with stored frozen material 6 months or less before enrolment into the study do not have to repeat a new biopsy