Mrs. A, a 68years old,normotensive non-diabetic female, previously diagnosed with CML- CP (EUTOS score 83)  in September,2023 with H/O anaemia, and abdominal discomfort. Qualitative BCR-ABL1 positive for mBCR(210kD). The patient was treated with 400mg of imatinib and had a complete hematologic response within one and a half months. At 3 months of starting Imatinib, the patient developed pancytopenia (Grade 2 Hematologic toxicities; Hb 7.8g/dl, ANC 1450/cmm, platelet -56000/cmm) which persisted for more than 2 weeks. Imatinib was stopped for 2 wks, and count recovered within 10 days of discontinuation of imatinib. Then 300mg of imatinib was started and one month of 300mg imatinib again grade 2 hematologic toxicities developed. Again imatinib stopped for 2 wks and after count recovered imatinib 200mg started. This 200mg dose maintained for 12 months with CBC monitoring only.

No molecular and cytogenetic response was monitored during this course of illness. At 17 months of imatinib  CBC shows grade 3 haematologic toxicity.  Again imatinib stopped and count didn’t recover even after 4 wks of discontinuation. So, pt undergone Bone marrow study, which shows Hypocellular marrow without any atypical cells and this time BCR- Abl quantitative PCR shows 36.7% BCR-ABL oncogene in IS%.
[25/11, 9:36 am]. Now what do we do next?

The details are quite limited. The patient is poorly tolerant of imatinib due to haematological toxicity and looks to have never achieved a cytogenetic response. In this situation, I would switch to a second generation TKI – bosutinib would be my preference, but nilotinib or dasatinib would also be OK, depending what local experience and preference are. I would also support with G-CSF and Erythropoietin if required and if available locally.