Patients undergoing bone marrow transplantation have an increased risk of new solid cancers later in life. The trend toward an increased risk over time after transplantation and the greater risk among younger patients indicate the need for life-long surveillance.

Transplant recipients have been reported to have an increased risk of solid cancers but most studies are small and have limited ability to evaluate the interaction of host, disease, and treatment-related factors. In the largest study to date to evaluate risk factors for solid cancers, we studied a multi-institutional cohort of 28 874 allogeneic transplant recipients with 189 solid malignancies. Overall, patients developed new solid cancers at twice the rate expected based on general population rates (observed-to-expected ratio 2.1; 95% confidence interval 1.8-2.5), with the risk increasing over time (P trend < .001); the risk reached 3-fold among patients followed for 15 years or more after transplantation. New findings showed that the risk of developing a non-squamous cell carcinoma (non-SCC) following conditioning radiation was highly dependent on age at exposure. Among patients irradiated at ages under 30 years, the relative risk of non-SCC was 9 times that of nonirradiated patients, while the comparable risk for older patients was 1.1 (P interaction < .01). Chronic graft-versus-host disease and male sex were the main determinants for risk of SCC. These data indicate that allogeneic transplant survivors, particularly those irradiated at young ages, face increased risks of solid cancers, supporting strategies to promote lifelong surveillance among these patients. (Blood. 2009; 113:1175-1183)

REATMENT OF HODGKIN DISease (HD) represents one of the major medical successes of the 20th century. Fifty years ago, the typical patient survived only a few years, 1 whereas the current 5-year relative survival rate is 85%. 2 In the United States alone, approximately 120000 survivors of HD 2 are at risk for the serious late sequelae of curative therapies, including the occurrence of new primary cancers. 3,4 Second malignant neoplasms are now the leading cause of death in longterm survivors of HD, 5,6 with breast cancer representing the most frequent solid tumor among women. 7,8 Estimates of breast cancer risk appear inversely related to age at treat-Author Affiliations are listed at the end of this article.

Since 2001, the World Health Organization classification for hematopoietic and lymphoid neoplasms has provided a framework for defining acute leukemia (AL) subtypes, although few populationbased studies have assessed incidence patterns and patient survival accordingly.We assessed AL incidence rates (