<qa>  What is the maximum tolerable dose of lutetium?This study is a phase 1, dose finding, open-label study in patients with relapsedrefractory diffuse large B-cell lymphoma DLBCL. This is a dose escalating study to define the maximum tolerable dose of lutetium 177Lu-lilotomab satetraxetan Betalutin in DLBCL patients who are not eligible for autologous stem cell transplant. The study will also assess safety and toxicity, pharmacokinetics, biodistribution and efficacy. 