Hematology

Hematology Table of Contents

Summary of Heme Oncology

Cell Lines (Simple)

Hematopoietic Growth Factors

• Erythropoietic Stimulating Agents (ESAs)
  • Benefits:
    • Increase Hb
    • Can improve anemia-related symptoms
  • Risks!!! (use with caution)
    • Increase in all-cause mortality, cardiovascular disease, and stroke (thrombogenic)
    • Lower survival in patients with solid tumors (perhaps due to increased thromboembolism or inferior level of tumor control??)
    •  

  • Indications: Generally use of erythropoietic growth factors in cancer is restricted to those with symptomatic chemo-related anemia with Hb < 100 and treatment is NOT curative. (Do not target >110). Must check/follow iron stores, target: Iron Saturation > 20%, and ferritin >100  Works better when iron levels are sufficient

  • In dialysis: Target Hb=100-110 (lower than before)... Use lowest dose necessary to reduce the need for erythrocyte transfusion.
  • Check Iron stores before and during treatment.  
     
• GCSF (GmCSF no longer avaialble)
  • Avaialble in regular and pegylated form.
  • Stimulate production of neutrophils in:
    • Primary prophylaxis in myelosuppressive chemo and cancers with high risk of febrile neutropenia such as lung/bladder ca...
    • Also used in infectious complications in non-maligant diseases (i.e. autoimmune neutropenia) with high risk of infection.
  • DO NOT deliver these agents <24hrs after chemo (promote cell cycle).
• Thrombopoietin Memetics
  • Restricted to use only in ITP

Hematopoietic Stem Cell Transplant (HSCT)

• HSCT used to treat:
  • Hematologic Malignancies
  • Congenital/Acquired bone marow failure syndromes
  • Other disorders...
• Two sources: Autologous (own) and Allogeneic (from HLA-matched donor).
• Steps:
  • 1. Mobilize stem cells with high doses of GCSF, increases CD34+ stem cells (stem cell marker).
  • 2. Conditioning therapy
    • Give myeloablative doses of cytotoxic chemotherapy +/- total body irradiation.
    • Eradicate residual disease + allow stem cells to engraft.
    • High risk (splenic, pulmonary hemorrhage), so now looking at less-intensive myeloablative therapy. (i.e. fludarabine).
      • Also allows some older patients to be eligible. (>60yo)
      • Using lower-intensity conditioning decreased early toxicity/mortality.
• The idea with autologous SCT is a rescue to repopulate the BM, but the idea with allogeneic is graft-vs-tumor effect (it is a treatment).  Unfortunately also get graft-vs-host (GVHD) as well.j
• GVHD (generally from allogeneic)
  • Transplanted lymphocytes attack organs --> skin (rashes), GI tract (diarrhea), Liver (veno-occlusive disease, transamanitis), Eyes, Lungs, Bone Marrow.
  • Can moderate response with MTX and calcineurin inhibitors.

Thrombocytopenia and Anticoagulation

• Platelets 20,000-50,000 = DVT prophylaxis only (other anticoagulation including antiplatelet agents generally contraindicated)
• Platelets < 20,000 = No anticoagulation. (even if ACS)

Lymphadenopathy

• Causes:

  • Cause	Examples
    Cancer	Hematological vs. Non-Hematological
    Hypersensitivity	Serum sickness, Drugs, Vaccination, GVHD
    Infection	Viral (EBV, CMV, HIV) Bacterial (TB, Syphilis, cat scratch etc...) Chlamydial (LGV) Protozoan (Toxoplasma) Fungal (Histo) Rickettsia (Scrub Typhus) Helmith (filariasis)
    Connection Tissue	Lupus, RA, etc.
    Atypical LPD	Castleman, AILD
    Granulomatous Disease	Sarcoid, Wegener, berylliosis, silicosis
    Other	Sinus histiocytosis and massive lymphadenopathy (Rosai Dorfman)

• Malignancy?

  • Factor	Interpretation
    Age of Patient	More likely in older
    Location	(tonsillar less likely malignant, inguinal more likely)
    Size	Cancer more likely with incr. size
    Consistency Tenderness Appearance Mobility	Rocky hard (non-hematological cancer) Rubbery (Lymphoma) Tender (Infection) Fixed (non-heme cancer)
    Local v General	Local more likely reactive
    Other	fever, splenomegaly, etc..

• History:
  • Cat/kittens scratch? (toxoplasomosis)
  • Undercooked meat? (Toxoplasmosis)
  • Tick Bites (Lyme/Tularemia)
  • TB (TB adenitis)
  • Transplant (CMV, HIV, PTLD)
  • High Risk Sex (HIV, Syphilis, HSV, CMV, HepB)
  • IVDU (HIV endocarditis, HepB)
  • Hunter/sTra
  • Sothern US (coccidiomycosis)
  • Medications?
    • Allopurinol, Atenolol, Captopril, etc.... through hypersensitivity.

Splenomegaly

• Causes

  • Cause			Example
    Passive Congestion			Portal HTN, Budd-Chiari, CHF
    Work Hypertrophy			Chronic extravascular Hemolysis (herediatory spherocytosis)
    Infiltrate	Non-Neoplastic		- Infections, connective tissue dz (SLE, RA) granulomas (sarcoid) - All Myeloid/lymphoid malignancy (CML, MPN, Lymphoma) - Any (usually not that apparent)
    	Neoplastic	Hematological
    		Non-Hematological
    Acellular Infiltrate			Amyoid, storage disorders (Gaucher, etc)

Hematologic Emergencies

• Leukostasis
  • Lower WBC (Hydroxyurea, aggressive hydration)
• DIC
  • Give cryoprecipitate Fibrinogen > 1-1.5
• Tumor Lysis
  • Allopurinol (Xanthine oxidase inhibitor)
  • Rasburicase (converts uric acid) - add if a lot of electrolyte abnormalities

General Approaches