ABSTRACT
Flow cytometric diagnosis and minimal residual disease (MRD) assessment of precursor B-lineage acute lymphoblastic leukemia (B-ALL) are heavily dependent on CD19 based gating strategies. However, this approach is not optimal in the diagnosis and follow-up of CD19 negative or dim B-ALLs. Though CD19 negative B-ALLs are rare, in the current era of CD19 targeted immuno-therapy, CD19 negative B-ALL relapses are frequent. We have presented our cohort of 14 de novo CD19 negative and dim B-ALLs and have highlighted the difficulties faced during diagnosis and MRD assessment of these patients. We have also discussed the need to identify alternative B-lineage gating markers and strategies to deal with such scenarios.
Subject(s)
Antigens, CD19/analysis , Cell Separation , Flow Cytometry , Neoplasm Recurrence, Local/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Adolescent , Adult , Antigens, CD19/metabolism , Antineoplastic Agents, Immunological/pharmacology , Antineoplastic Agents, Immunological/therapeutic use , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cell Separation/methods , Child , Child, Preschool , Cohort Studies , Female , Humans , Male , Neoplasm Recurrence, Local/blood , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/immunology , Neoplasm, Residual , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/blood , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/immunology , Young AdultABSTRACT
Parallel arrangement of ß-pleated sheets by amyloidogenic proteins is a well known phenomenon. Rarely, amyloid fibrils undergo radial orientation to form globular structures called spherulites. These amyloid spherulites show Maltese cross pattern under polarized microscopy. The clinical significance of amyloid spherulites is undetermined. Amyloidogenic proteins like insulin and ß-lactoglobulin form spherulites in vitro. The senile plaques of Alzheimer's disease rarely form in vivo spherulites. Amyloid spherulites have been described in the liver and small intestine. For the first time, we document amyloid spherulite formation in the bone marrow biopsy of an AL amyloidosis patient.
