De novo malignancy in pediatric organ transplant recipients.

Study of 7,393 types of cancer that occurred in 6,934 organ transplant recipients showed that the pattern of malignancies that developed in pediatric recipients was very different from that of the general pediatric population and that of adult recipients. Tumors (334) occurred in 326 pediatric patients (aged < or = 18 years), and 7,059 neoplasms occurred in 6,608 adults. Lymphomas were the predominant cancer in pediatric recipients and comprised 50% of all tumors compared with 15% in adult recipients. Among lymphomas in pediatric patients, 85% occurred during childhood. Of the patients who had lymphoma, there was a preponderance of recipients of nonrenal organs (61%); of those who had nonlymphomatous tumors, only 13% received nonrenal organs. The second most common malignancy in pediatric patients was skin cancer (20% of tumors), but this occurred less frequently than in adult recipients, for whom it comprised 38% of neoplasms. In only 11 pediatric patients (16%) did skin cancers develop during childhood (5 had malignant melanomas), with an average time of appearance after transplantation of 118 months (range, 9.5 to 282 months). Malignant melanomas were more common in pediatric than adult recipients (15% v 5% of skin cancers), as were lip cancers (29% v 13%). Spread to lymph nodes was also more common in pediatric than in adult recipients (13% v 6%). The third most common tumor (4%) in patients who had transplantation during childhood was carcinoma of the vulva, perineum, and/or anus. These patients were female, and the tumors occurred after childhood, at an average of 140 months (range, 43-262 months) posttransplantation.(ABSTRACT TRUNCATED AT 250 WORDS)