An important development in patient treatment occurs when indolent lymphomas develop an aggressive histology, which necessitates a shift in therapy. Although the prevalence of transformation is generally falling, it is still a very dangerous situation with a poor prognosis when compared to patients who do not have transformation. CAR-T has helped, but overall, the prognosis for patients with transformed lymphomas is still quite poor, especially if hematopoietic stem cell transplant (HSCT) or cellular therapy methods are not accessible or are ineffective. The top priority at this time should be to enroll the patient in a clinical trial.