Second Malignant Neoplasm
Bone Marrow Transplant
The cumulative incidence of risk a second cancer after BMT is about 5 - 12%.
Children - especially if they are less than 5 years old at the time of transplant, have a 50X risk over the general population of developing a second neoplasm.
The cumulative risk of developing a second cancer increases with age.
Risk is due to a combination of:
- Immunosuppression
- Exposure to radiation therapy (RT)
- Exposure to high dose chemotherapy
Types of cancer seen:
Tumors occur which are typically associated with immunodeficiency
- Lymphomas:
- EBV post transplant lymphoproliferative disease common (EBV-PTLPD)
- Incidence very increased in children with underlying immunodeficiency
- Most PTLPD is B-cell in origin
- Squamous cell cancers of skin are very common:
- Virus associated cancers are seen - for example squamous cell cancers of the skin, cervix and anus (associated with papilloma virus)
- Other Epithelial cancers:
- RT and chemotherapy causes DNA damage and an increased risk for epithelial cancers (such as thyroid cancer)
- Renal cancers:
- Reduced cellular immunity increases the risk of tumors such as renal cancer
- Leukemias/MDS:
- Due to DNA damage and associated with immunosupression
The prognosis for patients who develop a second cancer after BMT is generally very poor with a median survival of less than 2 years.
