Case 1
A male pediatric patient aged 6 years and 4 months was admitted for “coughing for more than half a month” in April 2014. The bone marrow aspirate was verified as showing B-ALL by flow cytometry. TheBCR-ABL fusion gene was shown to be positive by fluorescencein situ hybridization (FISH). BCR-ABL (P190) was quantified as 76%; karyotype analysis revealed chromosomal translocation with t(9; 22) (q34;q11) [20]. Therefore, the MICM diagnosis was Ph+ B-ALL. In accordance with the CCLG-ALL-2008 protocol, DVLDex regimen chemotherapy combined with oral imatinib was administered. After 9 months (June 2015) of treatment, the patient’s BCR-ABL (P190) decreased to 0.048%, as detected in the bone marrow, and the TKI treatment was changed to dasatinib. In March 2016, the bone marrow BCR-ABL fusion gene copy number was below the detection limit, and the peripheral blood BCR-ABL fusion gene copy number remained below the detection limit in the subsequent reexamination. The pediatric patient was treated with sequential chemotherapy until 2017, and then continued to take dasatinib without regular follow-up after completion of chemotherapy.
On September 11, 2021 (after treatment with dasatinib for more than 6 years), the patient was hospitalized again for paroxysmal cough, sustained fatigue, and shortness of breath after activity. Chest radiography demonstrated pulmonary infection and pleural effusion. Echocardiography showed enlargement of the right cardiac cavities, widening of the pulmonary artery, moderate to severe tricuspid regurgitation, pulmonary hypertension (136 mmHg; the normal pulmonary artery systolic pressure [PASP] was <25 mmHg and >18 mmHg) and massive pericardial effusions. The patient was told to discontinue oral dasatinib immediately, underwent pericardial drainage on September 11, 2021, and then received captopril, plavix, and sildenafil orally to treat PAH. Doppler echocardiography revealed that the cardiac function had returned to normal and the PASP was not further aggravated during the treatment period. The patient was prescribed symptomatic treatment for PAH with continued oral bosentan, sildenafil tablets, and poliovel after hospital discharge on October 14, 2021, and the TKI treatment was changed to oral nilotinib on December 23, 2021. Cardiac ultrasound showed that the cardiac structure had returned to normal, and the PASP had decreased to 22 mmHg after discontinuation of dasatinib for four months (January 2021). Subsequently, the PASP remained normal at scheduled reexaminations (Table 1 and Figure 1), and the patient no longer experienced fatigue and shortness of breath.