IKZF1 and KRAS Mutated B-cell Acute Lymphoblastic Leukemia with Pseudo-Chédiak-Higashi Granules.

We present the case of a 78-year-old patient with B-cell acute lymphoblastic leukemia (B-ALL), characterized by the presence of pseudo-Chédiak-Higashi (PCH) granules in lymphoblasts. A morphological analysis using transmission electron microscopy revealed heterogeneous blasts with irregular and bilobed nuclei containing PCH granules, identified as autophagosomes. A genomic analysis revealed mutations in IKZF1 and KRAS. The patient's condition was refractory to induction chemotherapy. The morphological heterogeneity of B-ALL with PCH granules poses a diagnostic challenge. Few reports have so far described cases of B-ALL with PCH granules refractory to induction therapy, thus highlighting the need for further investigation to better understand its clinical and pathological features.