Second Malignant Neoplasms
Summary of Key Points
• Subsequent malignancies after successful treatment for cancer occur in a meaningful minority of persons.
• Etiology is often multifactorial and includes known hereditary conditions, unrecognized genetic predisposition, primary cancer, therapeutic exposures, age, and lifestyle practices.
• Guidelines for screening are available for some but not all situations; health care providers and patients should be aware of such guidelines.
• Further research is needed to identify persons at highest risk so more useful preventive strategies can be developed.
1. Which of the following chemotherapy agents is most associated with risk for subsequent leukemia or myelodysplastic syndrome?
2. What is the most common second solid cancer after treatment for Hodgkin lymphoma in children, adolescents, and young adults?
3. What environmental or lifestyle exposure is most associated with increased risk of subsequent malignancy?
1. Answer: C. Mechlorethamine is potentially one of the most leukemogenic of the alkylating agents, particularly when given together with procarbazine for Hodgkin lymphoma in the mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) regimen. Risk decreased with changes in therapy that included fewer cycles of MOPP and with substitution of mechlorethamine with cyclophosphamide.
2. Answer: B. The most common solid malignancy after treatment for Hodgkin lymphoma in children and adolescents and young adults, particularly younger than 30 years, is breast cancer, with radiotherapy markedly increasing risk in a dose-dependent fashion.
3. Answer: A. The excess absolute risk for a subsequent malignant neoplasm occurring at sites related to tobacco exposure is elevated. Risk for lung cancer after Hodgkin lymphoma and cancer of the upper aerodigestive system is elevated with tobacco use.
