Core Concepts
A 65-year-old woman with unintended weight loss and fatigue was diagnosed with chronic-phase chronic myeloid leukemia (CML) after comprehensive evaluation, and was successfully treated with a tyrosine kinase inhibitor.
Abstract
The content describes the case of a 65-year-old woman who presented with concerns of recent unintended weight loss and fatigue. Upon further evaluation, she was found to have splenomegaly and an elevated white blood cell count with low leukocyte alkaline phosphatase (LAP) levels.
The differential diagnosis considered various disorders that can cause splenomegaly and leukocytosis, including autoimmune disorders, infections, and myeloproliferative disorders. After performing a peripheral blood smear and bone marrow biopsy, the patient was diagnosed with chronic-phase CML, which was confirmed by the presence of the Philadelphia (Ph1) chromosome and BCR::ABL1 transcripts.
The patient was treated with the tyrosine kinase inhibitor (TKI) imatinib as primary therapy, and her disease was monitored using quantitative reverse transcription polymerase chain reaction (RT-PCR) to measure BCR::ABL1 transcripts. She achieved positive early response indicators at 3 and 6 months, indicating a favorable prognosis.
The content also discusses the recommended initial evaluation and monitoring for CML patients, including the use of bone marrow cytogenetics, FISH, and RT-PCR on peripheral blood to detect and quantify BCR::ABL1 transcripts. The choice of first-line TKI therapy is based on risk stratification, patient characteristics, and comorbidities. The main treatment goal is to achieve a complete cytogenetic response and major molecular response, which are associated with improved long-term outcomes.
Stats
The patient's white blood cell count was elevated (> 40,000 cells/µL) with low leukocyte alkaline phosphatase (LAP) levels.
Peripheral blood smear showed a leukoerythroblastic blood picture with 10% peripheral blast cells.
Bone marrow biopsy showed hypercellularity with expansion of myeloid and myeloid progenitor cells.
Cytogenetic studies confirmed the presence of the Philadelphia (Ph1) chromosome and BCR::ABL1 transcripts.
The patient's BCR::ABL1 transcripts were 6% positive at 3 months and 2% positive at 6 months, indicating a positive early response to imatinib therapy.
Quotes
"Quantitative RT-PCR is a molecular technique used to measure the amount of specific RNA in a sample. The results of this test can be expressed in different ways, such as the ratio of BCR-ABL1 transcripts to control."
"Achieving an early molecular response (≤ 10% BCR::ABL1 on the international scale) at 3 and 6 months post-initiation of TKI therapy is a strong indicator of favorable long-term progression-free survival and overall survival."