Pediatric solid tumors and second malignancies: characteristics and survival outcomes.
BACKGROUND
To examine the incidence, characteristics, and outcomes for second malignancies following the diagnosis of a primary solid tumor in pediatric patients.


METHODS
The Surveillance, Epidemiology, and End Results (SEER) database was queried from 1973 to 2005, excluding recurrences, in patients <20 y.


RESULTS
A total of 31,685 cases of pediatric solid malignancies were identified. Overall, 177 patients were diagnosed with a unique second malignancy before the age 20 (0.56%) The mean follow-up was for 8.5 y (2 mo-30.8 y). Mean age at diagnosis of the primary tumor was 7.7 y. The most common primary malignancies were CNS tumors (22.5%), followed by soft tissue sarcoma (15.8%), retinoblastoma (14.1%), and bone tumors (13%). Hematologic malignancies (35.5%) were the most common second malignancies noted in the cohort, followed by bone tumors (18%) and soft tissue sarcomas (15%). Hematologic malignancies had a shorter latency (3.1 y) compared with solid second tumors (11.6 y). The overall 10-y survival for the entire cohort was 41.5%. For most tumor categories, development of a secondary malignancy was associated with lower 5- and 10-y survival than expected.


CONCLUSIONS
CNS tumors, retinoblastoma, and soft tissue sarcomas in children are the most common solid primary tumors, with an increased risk of a second malignancy. Leukemia is the most common second malignancy seen in pediatric solid tumors. Second malignancies are associated with significantly reduced survival rates compared with the general childhood cancer population.
Vasudevan
Vanitha
V
DeWitt Daughtry Family Department of Surgery, University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
Cheung
Michael C
MC
Yang
Relin
R
Zhuge
Ying
Y
Fischer
Anne C
AC
Koniaris
Leonidas G
LG
Sola
Juan E
JE
D000293:Adolescent; D001859:Bone Neoplasms / Q000401:mortality; D016543:Central Nervous System Neoplasms / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D019337:Hematologic Neoplasms / Q000401:mortality; D006801:Humans; D015994:Incidence; D008297:Male; D009369:Neoplasms / Q000401:mortality*; D016609:Neoplasms, Second Primary / Q000401:mortality*; D012175:Retinoblastoma / Q000401:mortality; D018426:SEER Program; D012509:Sarcoma / Q000401:mortality; D012983:Soft Tissue Neoplasms / Q000401:mortality; D016019:Survival Analysis; D055815:Young Adult