Current treatment preferences in chronic myeloid leukemia: The Mayo Clinic Physicians' survey
Authors: Kebede Begna, Aref Al‐Kali, Michelle Elliott, James Foran, Naseema Gangat, William Hogan, Christopher Hook, Jose Leis, Mark Litzow, Ruben Mesa, Jeanne Palmer, Animesh Pardanani, Mrinal Patnaik, Candido Rivera, Lisa Sproat, Raoul Tibes, Alexandra Wolanskyj‐Spinner, Ayalew Tefferi
Journal: American Journal of Hematology (2017)

Three tyrosine kinase inhibitors (TKIs; Imatinib, Dasatinib, and Nilotinib) are currently approved for first-line therapy of chronic phase chronic myeloid leukemia (CP-CML). National Cancer Comprehensive Cancer Network (NCCN) guidelines for the management of CML are noncommittal, as are most published expert opinions, in terms of TKI drugs of choice as first-line or second-line therapy.1 Hematologists and medical oncologist sometimes consider host comorbidities, Sokal score, specific drug side effects, and rapidity of clearance of leukemia burden, among other factors, in determining which TKI to choose. To date, none of the second generation TKIs have shown an overall survival advantage over imatinib.2, 3 Monitoring of treatment response is usually accomplished by complete blood count measurements, bone marrow (BM) cytogenetic analysis, and peripheral blood (PB) Fluorescence In Situ Hybridization (FISH) or quantitative reverse transcription polymerase chain reaction (qRT-PCR) of the chimeric BCR/ABL1 mRNA transcript level. In the current report, we explored the management of CML, in terms of Mayo Clinic physicians' preference of TKI for first- and second-line treatment of CP-CML and an accelerated phase CML (AP-CML). The survey was sent out to 18 physicians with expertise in the treatment of patients with myeloid neoplasms, including CML (Table 1). The results indicated that 89% (16/18) of the respondents preferred imatinib and 11% (2/18) nilotinib as first-line therapy for CP-CML; Sokal score was mentioned as a factor for TKI selection by 20% (3/15). In regards to second-line therapy, in the absence of kinase domain mutations, 73% (11/15) chose dasatinib, and 27% (4/15) nilotinib. For AP-CML, 67% (10/15) chose dasatinib and 27% (4/15) high dose imatinib as the preferred TKI. What is your typical first line treatment for chronic phase CML? Do you consider Sokal score when you select first line treatment for chronic phase CML? If yes, please elaborate How do you monitor molecular treatment response in patients starting TKI for chronic phase CML? In a patient with documented complete cytogenetic response, how often do you repeat bone marrow examination? In a patient who achieve molecular remission by FISH or PCR before completing 12 months of therapy do you perform (early or around 12 months' time period) bone marrow biopsy? When do you switch treatment to second line TKI? Please write your answer(s) What is your preferred second line TKI in the absence of abl mutations? What is your preferred first line treatment for accelerated phase CML? Do you consider allogenic stem cell transplant in patients with chronic phase CML? Yes If yes please write your reason(s) In regards to monitoring of treatment response, 86% (12/14) of the respondents used PB RT-PCR and 14% (2/14) used both FISH and RT-PCR, every 3 months. After a patient achieved complete cytogenetic response, 87% (13/15) of the physicians did not consider repeating BM biopsy for monitoring purposes. When molecular remission was documented by PB FISH or RT-PCR, 60% (9/15) of the respondents did consider BM biopsy to document cytogenetic response while 40% (6/15) did not. The current survey reveals that the majority of Mayo Clinic myeloid group physicians use imatinib and dasatinib as first- and second-line therapy for CP-CML and dasatinib for AP-CML. The survey also reveals substantial variation in the methods and schedules of monitoring treatment response. However, the results of the current study cannot be generalized to represent the general practice in the US; in that regard we plan to expand the current survey by including additional academic and nonacademic medical centers.