Review of Rare Association between Chronic Lymphocytic Leukemia and Chromic Myeloid Leukemia

Introduction:

Chronic lymphocytic leukemia (CLL) and chromic myeloid leukemia (CML) are the most found in elderly patients, with CLL being the most prevalent type of leukemia among older adults in Western nations. CML is the most common myeloproliferative neoplasm (MPNs). However, coexisting in a single patient is very rare and there are few documented cases of this in medical literature. Cases reported as sequential, where CML followed CLL diagnosis, vise versa or at the same time .

Methodology:

we preformed systematic literature review Our inclusion criteria included articles that presented cases of confirmed CLL associated with CML, whether diagnosed simultaneously or sequentially. Cases of CLL associated with Philadelphia negative MPNs were excluded from this review The search strategy used during our review with specified terms on both PubMed and Google Scholar.

Results

Twenty- six articles were found. All of them were cases reports. each case included one patient who had CML and CLL. Males were sightly predominant with 13/23(57%) compared to 10 females (3 cases they did not report) and mean age was 63.1. The mean of initial laboratory investigations at diagnosis showed HB 14.9 g/dl, WBC 52.6x10^3/uL, uL, Platelet 440x10^3/uL, . B symptoms were reported in 8 out 15 patients 57 %. The examination, a total of 13/21 (62%) found to have splenomegaly. CLL diagnosed first before CML in 13/26 (50%) of all cases and most common sequence. The second most common were concomitant presentation of CML and CLL presented at same time with 7 patients (27%). last group with 23 % those who had CML before CLL. The mean time difference between the two-diagnosis wither CLL first or CML around 44 months while the median was 48 (2 years). Cases of CLL First treated with wait and watch or chemotherapy 7/13 (54%) , chemotherapy protocols were FCR or Chlorambucil as most of reported cases before Bruton Tyrosine Kinase Inhibitors (BTK) era. The median exposure to chemotherapy was 36 months. Overall survival was 77 %, 6 patients died from different reasons including disease progression or febrile neutropenia and others.

Conclusion

CLL and CML associations is very rare only 26 cases reported in the literature till the moment. Both diseases can occur before each other or simultaneously.Since, majority of cases CLL diagnosed firstraising the possibility of therapy related mechanism secondary to chemotherapy previous exposure, specially most of them happened before BTKs . More studies and collaboration with large number is needed to study the mechanism and pathophysiology of this association. Currently there is no guidelines on how to treat patients with simultaneously CLL and CML .

No relevant conflicts of interest to declare.