Coexistence of three hematological malignancies in association with a first time documented mutation: "One train can hide another"°, and even more!

Coexisting malignancies is not only an uncommon event but, it can also represent a medical challenge. Its complexity relies on the difficulty of management and the need for personalized and prioritized therapeutic approaches, on the one hand, and in the potential misdiagnosis of recurrence or even a de novo disease, on the other. Here, we present a case of a 69-year-old patient, who was initially diagnosed with a chronic myelomonocytic leukemia (CMML), followed by monoclonal gammopathy of uncertain significance (MGUS). Few years later, the patient developed Hodgkin's lymphoma (HL), and a new mutation, previously undocumented in the medical literature, was also detected. As a conclusion, we can say that the decision must be taken with caution and must be based on two major factors: 1- The rapid evolution of malignancies: give priority to treating the most rapid/life-threatening disease. 2- Prioritize the treatment of symptomatic disease and/or that which may most improve patients' quality of life.