Patients Age 40 Years and Younger With Multiple Myeloma Have the Same Prognosis as Older Patients: An Analysis of Real-World Patients' Evidence From Latin America.

PURPOSE: Multiple myeloma (MM) is a highly heterogeneous, incurable disease most frequently diagnosed in the elderly. Therefore, data on clinical characteristics and outcomes in the very young population are scarce. PATIENTS AND METHODS: We analyzed clinical characteristics, response to treatment, and survival in 103 patients with newly diagnosed MM age 40 years or younger compared with 256 patients age 41-50 years and 957 patients age 51 years or older. RESULTS: There were no statistical differences in sex, isotype, International Scoring System, renal involvement, hypercalcemia, anemia, dialysis, bony lesions, extramedullary disease, and lactate dehydrogenase (LDH). The most used regimen in young patients was cyclophosphamide, bortezomib, dexamethasone, followed by cyclophosphamide, thalidomide, dexamethasone and bortezomib, thalidomide, dexamethasone. Of the patients age 40 years or younger, only 53% received autologous stem-cell transplant (ASCT) and 71.1% received maintenance. There were no differences in overall survival (OS) in the three patient cohorts. In the multivariate analysis, only high LDH, high cytogenetic risk, and ASCT were statistically associated with survival. CONCLUSION: In conclusion, younger patients with MM in Latin America have similar clinical characteristics, responses, and OS compared with the elderly.

Myelomastocytic Blast Cell Crisis in Resistant Tyrosine Kinase Inhibitor Chronic Myelogenous Leukemia: Case Report and Review of Literature.

We present the clinical case of a 29-year-old male with a diagnosis of chronic myeloid leukemia (CML) in high-risk chronic phase since February 2010. He started treatment with imatinib at a dose of 400 mg obtaining a hematologic response early but without reaching a cytogenetic response in month 18. Then, dasatinib was prescribed. The BCR-ABL transcription level of 58% was documented. It was decided to start treatment with nilotinib but in March 2017 we diagnosed a progression to blast crisis (BC) of myeloid origin with a bone marrow study that documented 72% of blasts with normal karyotype, also very striking, the concomitant skin infiltration, bone lesions of lytic type and hypercalcemia that required the use of zoledronic acid as an emergency. At the end of chemotherapy induction with 7 + 3 (seven days of cytarabine and three days of idarubicin) chemotherapy associated with bosutinib for 14 days and after several infectious complications, we documented a percentage of blasts by flow cytometry of 29% in the bone marrow and the existence of 46% of cells with basophilic characteristics versus mast cells. A basophilic transformation was suspected versus aggressive systemic mastocytosis with a clonal, nonmastocytic hematological disorder. Levels of serum tryptase and mutation D816V C KIT were requested, which were not possible to perform. Treatment with CLAG-M was proposed, however, the patient died early with hyperleukocytosis and severe thrombocytopenia with central nervous system bleeding.