This is a mature B cell #Leukemia. Morphologically, neoplast | Figure 1

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This is a mature B cell #Leukemia. Morphologically, neoplastic cells have too much cytoplasm to be blasts/immature. On the #Flow-cytometry you can see the abnormal population is 72% of WBCs and expresses CD5, CD19, CD20, and surface kappa light chain. That tells us it's a B cell leukemia/lymphoma (CD19 & 20) and the differential includes #Mantle-cell-lymphoma and transformed #Chronic-lymphocytic-leukemia as well as leukemic #Diffuse-large-B-cell-lymphoma. #Mantle-cell-lymphoma was ruled out by cytogenetics for t(11;14).

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Case Summaries

Case 1

A 56-year-old female commences induction therapy with rituximab and hyper-CVAD chemotherapy for her Philadelphia chromosome-negative, CD20+ precursor B-cell acute lymphoblastic leukemia (ALL). Staging studies following her induction treatment, including bone marrow biopsy and laboratory analysis, reveal that she has attained a complete remission. However, PCR analysis reveals that she is minimal residual disease (MRD) positive (>0.1%). She has an outstanding performance status. Which of the following therapies would you recommend?

Case 2

A 27-year-old female, G2P1001, who is in the second trimester of her current pregnancy, presents to the emergency department with complaints of fever, fatigue, and chin numbness which has been present for the last week without any changes. On examination, the numbness in the chin is confirmed. In addition, she is found to have hepatosplenomegaly. Laboratory testing is ordered, and before results are obtained, the laboratory calls to report the presence of blasts in the peripheral smear. Oncology is consulted, and flow cytometry is performed, which is significant for precursor B-cell Acute Lymphoblastic Leukemia (Pre-B-ALL), based on the strong expression of CD19, CD22, CD79a, TdT, HLA-DR, and cytoplasmic IgM, and negativity for CD20 in a population of cells consistent with blasts. A rush cytogenetics workup is positive for [t(9;22)] (Ph). Systemic therapy is to be initiated.

Case 3

A 4-year-old girl presents to the emergency department with multiple bruises on her limbs and recent weight loss of 4 lb. When asked, the patient’s mother reports that the child has been progressively fatigued and seems to be weak. The patient’s past medical history is significant for hemophagocytic lymphohistiocytosis, for which she was treated with etoposide, corticosteroids, cyclosporine, and intrathecal methotrexate. She then received a bone marrow transplantation. Her current complete blood cell count shows anemia, thrombocytopenia, and marked lymphocytosis with 88% blasts. The peripheral smear is shown in Figure 1.

Which one of the following statements regarding the phenotypic characteristics of acute leukemia is true?
A. CD19 expression is almost never observed in AML.
B. Terminal deoxynucleotidyl transferase (TdT) can be positive in a subset of AMLs.
C. It is not uncommon to see the absence of CD19 on B-cell lymphoblastic leukemias.
D. If the lesional cells express CD13, they must be of the myeloid lineage.
E. CD117 is commonly seen in ALL.

Case 4

A 52-year-old man presented with a 20-minute history of chest pain radiating to the left shoulder and neck, associated with dyspnea and diaphoresis. He had a history of hypertension, long-term smoking, and a sedentary lifestyle. On physical examination, bibasilar crackles were noted on lung auscultation. An electrocardiogram (ECG) was performed in the primary care setting, and the patient was promptly referred to the emergency department.

Case 5

A 28-year-old woman presented with a 3-day history of intense pruritus over the lower back. She reported no recent travel or exposure to new environments. She cares for a small kennel with approximately eight dogs rescued from the streets. Physical examination revealed multiple small vesicles, some clustered and others scattered, predominantly involving the lumbar region and the left gluteal area.

Case 6

A 4-month-old male infant presented with skin lesions localized to the chin for the past 3 days. Physical examination revealed multiple small pustules with surrounding inflammatory signs on the chin, along with a few scattered papules on the chest.

Summary

This content provides valuable information about various cases and conditions related to leukemias and other medical issues. It is essential for medical professionals to examine these cases critically to enhance their knowledge in clinical practice.