What blood component does a breast cancer patient with severe thrombocytopenia, bruising, bleeding, and petechiae require, and what modification is needed for a donated apheresis product?

Platelet Transfusion Management for Breast Cancer Patient with Severe Thrombocytopenia

This patient with severe thrombocytopenia (platelet count 10,000/μL) and active bleeding requires immediate platelet transfusion to prevent life-threatening hemorrhage. The patient should receive a single-donor apheresis platelet unit, which must be irradiated before transfusion due to the donor being a relative of the patient.

Patient Assessment and Diagnosis

The patient presents with:

• Platelet count of 10,000/μL (severe thrombocytopenia)
• Active bleeding manifestations (gum bleeding)
• Petechiae (small hemorrhagic spots on skin)
• Normal hemoglobin (12.0 g/dL), hematocrit (36%), RBC count (3.6 x 10^6/μL)
• Normal WBC count (8.5 x 10^3/μL)
• Normochromic, normocytic RBC morphology

This clinical picture is consistent with isolated thrombocytopenia in a breast cancer patient, likely due to chemotherapy-induced bone marrow suppression.

Transfusion Requirements

Blood Component Needed

• Single-donor apheresis platelet unit (equivalent to 4-8 units of pooled platelets)
  • This dose should increase the platelet count by 30-50 × 10^9/L 1
  • A single apheresis unit contains approximately 3-4 × 10^11 platelets 1

Required Component Modification

• Irradiation of the platelet product is mandatory when the donor is a relative (the patient's brother)
  • This prevents transfusion-associated graft-versus-host disease (TA-GVHD)
  • Irradiation disables donor T-lymphocytes that could engraft and cause GVHD

Evidence-Based Rationale

1. Transfusion Threshold:

   • The ASCO guidelines recommend maintaining platelet counts above 10,000/μL for prophylactic transfusion in patients with hematologic malignancies 1
   • For patients with active bleeding (as in this case), transfusion is indicated regardless of the count
   • The patient's platelet count of 10,000/μL with active bleeding represents a clear indication for immediate transfusion

2. Dosing:

   • The recommended dose is one apheresis platelet product or 4-8 units of pooled platelets 1
   • This dose is sufficient to provide hemostasis in a thrombocytopenic, bleeding patient 1

3. Product Selection:

   • Single-donor apheresis platelets are preferred when using related donors 1
   • The platelet concentrate must be ABO-identical or at least ABO-compatible to provide good yield 1

4. Component Modification:

   • Irradiation is mandatory for cellular blood components from blood relatives to prevent TA-GVHD
   • This is particularly important in cancer patients who may be immunocompromised from their disease or treatment

Monitoring and Follow-up

• Assess clinical response after transfusion (cessation of bleeding)
• Check post-transfusion platelet count (1 hour after transfusion)
• Monitor for transfusion reactions
• Determine need for additional transfusions based on:
  • Persistence of bleeding
  • Post-transfusion platelet count
  • Underlying cause of thrombocytopenia

Potential Pitfalls and Caveats

1. Refractoriness to platelet transfusion:

   • May develop in patients receiving multiple transfusions
   • If poor increment is observed, consider HLA-matched platelets 1

2. Transfusion reactions:

   • Platelet transfusions have 3.25 times higher risk of severe reactions compared to RBC transfusions 2
   • Common reactions include allergic reactions and febrile non-hemolytic reactions

3. Short platelet survival:

   • In cancer patients, transfused platelets may have shorter survival due to consumption factors
   • More frequent transfusions may be needed

4. Alloimmunization:

   • Repeated transfusions increase risk of alloimmunization
   • May require HLA-matched platelets in future transfusions