Chronic Myeloid Leukemia (CML) is a highly curable malignancy with tyrosine kinase inhibitors (TKI) as target therapy. As treatment is usually prolonged, there is a need to improve our knowledge about the impact of comorbidities in this context. Severe obesity is among the common comorbidities in these patients. We present the case of a patient with morbid obesity and associated sleep apnea hypopnea syndrome who was succesfully treated during 14 years with imatinib, a cornerstone TKI for this disease. Visceral fat area was extremely elevated in this patient. Keywords: chronic myeloid leukemia; obesity; imatinib; sleep apnea hypopnea syndrome. Abbreviations: CML: Chronic Myeloid Leukemia; BMI: Body Mass Index; TKI: Tyrosine Kinase Inhibitors.