Pediatric Hematology and Oncology

62 questions

All types62 Multiple choice31 Matching16 Ordering15

A pediatric pathology team is correlating characteristic genetic and microscopic findings with their corresponding childhood malignancies. Match each specific diagnostic description with the most likely pediatric hematologic or oncologic diagnosis.

Click a left item, then click its matching right item

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Answer

Burkitt lymphoma matches with t(8;14) and 'starry-sky' pattern; B-ALL matches with TdT, CD10, and CD19 positivity; Neuroblastoma matches with adrenal mass, Homer-Wright rosettes, and N-myc amplification; Ewing sarcoma matches with diaphyseal bone lesion and t(11;22).

Each pediatric malignancy has classic defining features that guide diagnosis. Burkitt lymphoma is defined by t(8;14) and 'starry-sky' macrophages; B-ALL by TdT and CD10/19 positivity; Neuroblastoma by N-myc amplification in sympathetic tissues; and Ewing sarcoma by t(11;22) in bone diaphyses.

Step-by-Step Solution

Analyze the first diagnostic description: 'starry-sky' pattern and t(8;14).

This correlates with Burkitt lymphoma.

t(8;14) translocates the c-myc oncogene to the Ig heavy chain locus, driving the hyperproliferation seen in Burkitt lymphoma.

Analyze the second diagnostic description: TdT-positive blasts expressing CD10 and CD19.

This correlates with B-cell acute lymphoblastic leukemia.

TdT is a marker for immature lymphoblasts, while CD10 and CD19 are specific to the B-cell lineage.

Analyze the third diagnostic description: Adrenal mass with Homer-Wright rosettes and N-myc amplification.

This correlates with Neuroblastoma.

Neuroblastomas are neural crest-derived tumors that often arise in the adrenal medulla and are prognostically stratified by N-myc amplification.

Analyze the fourth diagnostic description: Diaphyseal bone biopsy with small round blue cells and t(11;22).

This correlates with Ewing sarcoma.

The t(11;22) translocation is the defining molecular alteration of Ewing sarcoma, which classically affects the diaphysis of long bones.

Key Concept

Correlation of molecular genetics and histologic findings with pediatric malignancies

Question 62Question →

A preschool-aged male is evaluated in the emergency department due to a new-onset fever of $39.4^\circ\text{C}$ ( $102.9^\circ\text{F}$ ) and extreme lethargy. The patient is currently in the consolidation phase of cytotoxic chemotherapy for an underlying high-risk neuroblastoma. Two days prior to arrival, an implanted central venous access port was surgically placed without immediate complications. On evaluation, he is tachycardic at $165/\text{min}$ , tachypneic at $32/\text{min}$ , and hypotensive with a blood pressure of $72/40\text{ mm Hg}$ . Capillary refill time is $4\text{ seconds}$ . The surgical site appears clean with no surrounding erythema, and the lungs are clear to auscultation. A complete blood count reveals a total leukocyte count of $400/\text{mm}^3$ with $10\%$ segmented neutrophils and $5\%$ band forms. What is the most appropriate next step in the management of this patient?

Transport the patient to the radiology suite for a computed tomography scan of the abdomen to locate the infectious source

Administer antipyretics and continue close observation, as the fever is an expected physiological response on postoperative day two

Administer the overdue live-attenuated measles, mumps, and rubella vaccine prior to hospital admission to prevent concurrent viral infections

Prescribe oral amoxicillin and arrange outpatient follow-up, as the absolute neutrophil count is evaluated to be safely above the threshold for severe neutropenia

Obtain blood cultures, administer rapid intravenous fluid boluses, and immediately initiate broad-spectrum antipseudomonal antibiotics

Show answer & explanation

Answer: Obtain blood cultures, administer rapid intravenous fluid boluses, and immediately initiate broad-spectrum antipseudomonal antibiotics

Answer

Obtain blood cultures, administer rapid intravenous fluid boluses, and immediately initiate broad-spectrum antipseudomonal antibiotics.

The correct course of action addresses two simultaneous life-threatening conditions: febrile neutropenia and impending septic shock. This patient has an absolute neutrophil count (ANC) of

60/\text{mm}^3

(calculated as

400 \times [0.10 + 0.05]

), which is firmly in the category of severe neutropenia (ANC

< 500/\text{mm}^3

). Combined with fever and clear signs of hemodynamic instability—including hypotension, prolonged capillary refill, and tachycardia—this clinical picture indicates an oncologic emergency. The absolute highest priority is rapid physiological stabilization. This involves administering intravenous fluid boluses to restore intravascular volume and immediately initiating empiric broad-spectrum antipseudomonal antibiotics (e.g., cefepime or piperacillin-tazobactam) after promptly drawing blood cultures. Any delay in delivering these interventions increases mortality.

Step-by-Step Solution

Calculate the absolute neutrophil count (ANC) using the provided laboratory values.

\text{ANC} = \text{Total WBC} \times (\%\text{ neutrophils} + \%\text{ bands})

. Thus,

\text{ANC} = 400 \times (0.10 + 0.05) = 60/\text{mm}^3

Accurately determining the ANC is crucial to identifying severe neutropenia (ANC

< 500/\text{mm}^3

) in oncology patients.

Evaluate the patient's vital signs and peripheral perfusion to assess hemodynamic stability.

The patient demonstrates tachycardia (

165/\text{min}

), hypotension (

72/40\text{ mm Hg}

), and prolonged capillary refill (

4\text{ seconds}

These findings are classic indicators of decompensated septic shock, which requires immediate, aggressive intervention.

Determine the priority of clinical interventions based on the diagnosis of febrile neutropenia with septic shock.

The immediate priority is resuscitation with intravenous fluid boluses and the administration of broad-spectrum antipseudomonal antibiotics following blood cultures.

In unstable patients, life-saving physiological stabilization and empiric treatment must precede any attempts at detailed diagnostic imaging or source localization.

Key Concept

Management of febrile neutropenia and impending septic shock in pediatric oncology patients.

Estimated Time:1m 30s

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Pediatric Hematology and Oncology

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