Investigating residual leukemic cells in acute lymphoblastic leukemia: a practical approach using a streamlined interphase fluorescence in situ hybridization method on cerebrospinal fluid.

INTRODUCTION: A precise diagnosis of central nervous system involvement in acute lymphoblastic leukemia (ALL) requires comprehensive knowledge of morphological analysis, with a focus on the quantity and quality of cells being examined. Some research has utilized techniques such as immunocytochemistry, flow cytometry, polymerase chain reaction (PCR), and interphase fluorescence in situ hybridization (iFISH) on cerebrospinal fluid (CSF) cytospin samples to detect any remaining leukemic cells in the CSF. To obtain reliable results using immunocytochemistry and flow cytometry, it is essential to use freshly collected specimens within a limited timeframe. At the same time, PCR requires a sufficient number of cells for DNA extraction. On the other hand, the iFISH procedure on CSF cytospin samples can be challenging and requires practice. Therefore, there is a need for a fast, easy method that will be affordable and marketable in laboratories where the above methods are not available, or the sample is insufficient to use those methods. METHODS: The samples were prepared by centrifugation of 1 mL aliquots of CSF collected into EDTA tubes. The CSF sample was centrifuged at 3000 rpm for 3 min, the supernatant was removed, and the pellet was placed in KCl hypotonic solution for 5 min at 37 °C. Other steps (fixation, hybridization, wash steps, and analysis) were the same as in the standard protocol for blood samples. The BCR-ABL1 rearrangements were performed and evaluated in 200 interphase cells. RESULTS: 90% of Ph(+) cells were found in CSF. CONCLUSION: We propose a significantly streamlined iFISH method for detecting blast/residual leukemic cells in acute lymphoblastic leukemia using CSF as a complementary test option.

Is it safe and efficacious to remove central lines in pediatric bone marrow transplant patients with platelets less than 20,000/µl?

Background: Patients with tunneled central venous lines (CVL) may develop bloodstream infections which at times are difficult to control without line removal. Concomitant severe thrombocytopenia with platelet transfusion refractoriness is often considered a major contraindication to any procedure involving a major blood vessel. There is very little literature on the clinical risks of tunneled central line removal in febrile pancytopenia patients. Procedure: We analyzed complications and outcomes in all our patients, a total of 52, who underwent CVL removal with platelets <20,000/µl. Results: CVL removal was done on a median day of 17.5 with 47 of the 52 patients never having achieved platelets engraftment prior to line removal. No bleeding episodes or unplanned transfusions could be associated with CVL removal. No other complications were also reported. All patients had time to hemostasis within 5 min of catheter removal. Removal of CVL under local anesthesia remained complication-free even at platelet counts less than 20,000/ul. A total of 31 patients were febrile at the time of CVL removal, of which 17 became afebrile within 2 days. We found no difference in defervescence when comparing those whose antibiotic therapy was changed/escalated versus those in whom it was not. Conclusion: Our findings suggest that central lines can be safely removed with platelet counts less than 20,000/ul and that this may result in enhanced bloodstream infection control. This might be particularly relevant to neutropenic patients in this day and age of multidrug-resistant organism emergence and paucity of new effective antibiotics.

Opsoclonus-Myoclonus-Associated Neuroblastoma With Bone Marrow Metastases: What Would Be the Best Treatment Option?

A 1.9-year-old girl was presented to the hospital with dancing eye movements, ataxia, and behavioral disorders. The MRI showed a retroperitoneal tumor (transversal size: 3.9 x 2.5 cm, craniocaudal size: 4.6 cm) extending from T12 to L3 vertebral bodies (Figure), which was suspicious for neuroblastoma. Afterwards, biopsy of the lesion and bone marrow was performed. The initial pathological evaluation (CD56+, PHOX2B+, NKX2-, Ki67 50%-55%, NSE+, CD99-) of the tumor and bone marrow confirmed the diagnosis of poorly differentiated, high-risk neuroblastoma.