Radiation Oncology/Hodgkin/Review

Review of Hodgkin's Lymphoma

Epidemiology

• US incidence: ~8000
• US deaths: ~1300
• Age: bimodal, peak in 20's and 50's
• Risk factors: likely genetic predisposition (increased incidence in Jews, siblings, HLA antigens)
• Two separate entities
  • Classical Hodgkin's Lymphoma (CHL) - Reed-Sternberg cells
  • Lymphocyte-predominant Hodgkin's Lymphoma (LPHL) - "popcorn" lymphocyte cells

Clinical Presentation & Workup

• Clinical presentation: lymph node mass(es)
• Diagnosis
  • Excisional lymph node biopsy
  • Core needle biopsy may be adequate
  • FNA is insufficient
• Pathology
  • CHL: Reed-Sternberg cells sufficient, CD15+ and CD30+
  • LPHL: CD20+ and CD45+, epithelial membrane antigen
• Workup
  • Determination of B symptoms: fever >38C, drenching sweats, weight loss >10% weight
  • Exam: lymphoid regions, liver, spleen
  • Labs: CBC, differential, ESR, LDH, albumin, LFT, Bun/Cr
  • Bone marrow biopsy: Stage IB/IIB, III-IV
  • Imaging: CT neck/chest/abdomen/pelvis or PET/CT
    • PET: higher sensitivity for nodal regions (92% vs 83%) and organ involvement (86% vs 37%), though more false positives
• Staging (Ann Arbor system; EORTC unfavorable criteria):
  • Early stage favorable (I-II, no unfavorable features)
  • Early stage unfavorable bulky (I-II, bulky mediastinum ratio >0.33 or size >= 10cm)
  • Early stage unfavorable non-bulky (I-II, B symptoms, or >3 sites of disease, or ESR >50)
  • Advanced (III-IV)
  • Advanced unfavorable (age >=45, male, stage IV, albumin <4, WBC >15k, WBC <600
• Response criteria
  • Need for additional treatment based on response
  • 2007 IWG Guidelines using IHC, flow cytometry, PET: CR, PR, SD, relapsed, PD