Chronic Myeloid Leukemia: A Clinicoepidemiologic and Therapeutic Description of a Single Institution in Mexico City

Background

Chronic myeloid leukemia (CML) is a malignant disease caused by the protein coded by the Philadelphia chromosome. Imatinib mesylate (IM) is now the treatment of choice for all stages of CML. Clinicoepidemiologic information on CML from developing countries is scattered in the current literature

Patients and Methods

We report on the clincoepidemiologic features and response to therapy with IM in a cohort of patients with all stages of CML at a Mexican institution. Additionally, we describe the failure rate of standard G-banding cytogenetics, and correlate the association of successful standard cytogenetics with fluorescence in situ hybridization (FISH) to validate the results of responses in our patient population. Ninety-nine medical charts were evaluated. Fifty-seven patients were treated with IM, and a historical group consisted of 42 patients.

Results

The median age was 37 years, and the median follow-up of the IM-treated cohort was 26.4 months. The correlation between cytogenetics and FISH was 0.719 (P = .01). The complete cytogenetic response was 88.1% in the IM-treated group, versus 4.8% in the historical group. Patients previously treated with interferon-α (INF-α) had a complete cytogenetic response of 58.8%, versus 77.8% of patients previously treated who were naive to INF-α.

Conclusion

Our report describes a comprehensive picture of a group of patients with CML representative of the Mexican population with socioeconomic and cultural constraints. Except for median age at diagnosis, clinicoepidemiologic features and response rates are in accordance with other series. Fluorescence in situ hybridization was a reliable method for monitoring CML at our institution. However, the role of FISH in monitoring CML, where standard cytogenetic testing and the polymerase chain reaction are less reliable, needs to be clarified more thoroughly.