Fluorescent In Situ Hybridization Monitoring and Effect of Detected Early Responses in the Outcome of Patients With Chronic Phase Chronic Myeloid Leukemia: A Report From a Latin American Country.
The cytogenetic hallmark of chronic myeloid leukemia (CML) is the Philadelphia chromosome. Monitoring the response in patients receiving therapy is a standard of care. The present study was conducted to assess the monitoring adherence and reliableness of fluorescent in situ hybridization (FISH) as a monitoring tool and the effect of a complete cytogenetic response (CCyR) assessed by FISH on the prognosis of patients in a chronic phase (CP)-CML cohort.



We retrospectively analyzed the data from 63 newly diagnosed CP-CML patients treated with imatinib mesylate at a dose of 400 mg/day as frontline therapy. The clinical data and cytogenetic test results at diagnosis and during monitoring were collected. The cytogenetic monitoring adherence assessment rates were measured. A correlation between chromosome banding analysis (CBA) and FISH was performed. The CCyR assessed by FISH was defined as < 1% BCR-ABL1(+) nuclei. The Kaplan-Meier method was used for overall survival analysis and time-to-event estimates.



The cytogenetic monitoring assessment adherence was 50.8% at 3 months, 93.5% at 6 months, 96.7% at 12 months, and 88.6% at 18 months. The Pearson correlation coefficient showed a significantly positive association (r = 0.84; P < .001) between CBA and FISH. The median follow-up duration after imatinib mesylate initiation was 60 months. A CCyR was achieved in 90.4% of patients within the first 18 months of therapy. At 3 months, 31 patients underwent a FISH evaluation, and 13 (41.9%) had achieved a CCyR. The patients who did not achieve a CCyR at 3 months had a significantly inferior probability of 5-year failure-free survival (38% vs. 94%; P = .001) and progression-free survival (80% vs. 100%; P = .043) compared with those with a CCyR.



We found improved monitoring adherence compared with the previous reports of Latin American populations. In countries with a high incidence of failure for CBA and a lack of real-time polymerase chain reaction standardization, FISH is a sensitive monitoring tool. In our cohort, patients not achieving an early CCyR, as tested by FISH, were a poor prognosis subgroup with worse rates of failure-free survival and progression-free survival.
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México.
Christianne
C
Bourlon
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México.
Carlos
C
Hernandez-Mata
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México.
Cesar
C
Vargas-Serafín
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México.
María T
MT
Bourlon
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México.
Elena
E
Tuna-Aguilar
Department of Hematology and Oncology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México. Electronic address: alvaroaguayo@hotmail.com.
Alvaro
A
Aguayo
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D014408:Biomarkers, Tumor; D002871:Chromosome Banding; D005260:Female; D005500:Follow-Up Studies; D016044:Fusion Proteins, bcr-abl / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D007843:Latin America; D015466:Leukemia, Myeloid, Chronic-Phase / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D047428:Protein Kinase Inhibitors; D016044:Fusion Proteins, bcr-abl
CP-CML; Chromosome banding analysis; Cytogenetic monitoring; FISH; Myeloproliferative disorders