Periodic acid schiff stain shows Block positivity in -: (A) Myeloblasts, (B) Lymphoblasts, (C) Monoblasts, (D) Megakaryoblasts
Answer is B. Lymphoblasts Myeloperoxidase: negative Sudan Black: negative Nonspecific esterase: negative PAS: block positivity Myeloblasts Myeloperoxidase: positive sudan black: positive nonspecific esterase: positive in M4 & M5 PAS: negative Ref: RAM DAS NAYAK 2nd Ed. Pg no:293