18. Tumors After Renal Transplation

  • Overall incidence of cancer: 6% (4-18%)
  • Incidence of tumors increases dramatically with time after transplantation
  • The most frequent encountered tumors: skin SCCs, NHLs, KSs, in situ carcinomas of the uterine cervix, carcinomas of the vulva and perineum, hepatobiliary carcinomas, sarcomas
  • The percentage of lymphomas (PTLD) within malignant tumors is 16-22% vs 5% in general population. Among patients given OKT3 lymphomas comprise the 54% of all tumors.
  • Incidence increases parallel to the intensity of immunosuppressive therapy.
  • The incidence of PTLD is higher in heart than renal transplants
  • Lymphomas appear at an average of 32 months (1-254)
  • Among lymphomas:
    • Hodgkin's disease: 2.5%
    • NHLs: 93% vs 65% in general population
    • Myelomas: 4%
  • Incidence of NHLs is increased 29-40 fold over that seen in age-matched controls
  • Among NHLs:
    • 88% are of B-cell origin: frequently immunoblastic or large cell
    • 12% are of T-cell origin
    • 51% :multiple organ involvement
    • 49%: single organ involvement
    • 70% showed extranodal site involvement vs 24-48% in general population
  • NHLs are thought to be EBV-induced, impairment of surveillance mechanisms, chronic antigenic stimulation by the allograft, viral oncogenesis, direct action of immunosuppresants
  • 2 types of lymphomas:
    early onset: within the 1st year
    children or young adults (23 y)
    presentation with IMNL syndrome
    response to conservative treatment
    late onset: older age (48 years)
    localized mass
    poor outcome