机译
具有白血病转化和类白血病反应的空细胞表型ALK +间变性大细胞淋巴瘤
摘要:Anaplastic large cell lymphoma (ALCL) frequently involves both nodal and extranodal sites and is rarely leukemic. A 21-year-old male presented with abdominal pain. His complete blood count, which had been normal four months ago, showed increasing white cell counts from 14.9x10 /L to 95.5x10 /L in a month, with neutrophils ranging from 81.6% to 89.6%. Blood cultures were negative. Laparoscopic nodal biopsy showed sheets of medium-sized lymphocytes diffusely expressing CD30, TIA-1, granzyme B, and ALK, but not T-cell markers including CD2, CD3, CD4, CD5, CD7, CD8, and βF1, indicating ALK+ ALCL of null cell phenotype. Bone marrow biopsy showed two small aggregates of tumor cells in a background of normal tri-lineage hematopoiesis. ALK immunostaining revealed singly scattered positive cells ( ) in addition to those in small aggregates. The staining pattern was both nuclear and cytoplasmic, indicating translocation t(2;5)(p23;q35). We retrospectively reviewed the blood smear and found that 4.5% of the last peripheral smear were tumor cells, which were overlooked by the clinical laboratory. The leukemic cells were large with vesicular nuclei, irregular nuclear contours, and vacuolated basophilic cytoplasm ( ). The disease progressed rapidly, and the patient passed away shortly after the first cycle of CEOP chemotherapy. In advanced diseases, ALK-positive ALCL may rarely be associated with leukemoid reaction and leukemic transformation.