Non-Hodgkin's lymphoma arising in bone in children and adolescents is associated with an excellent outcome: A Children's Cancer Group report

Purpose: Non-Hodgkin's lymphoma (NHL) arising in bone is a heterogeneous histologic type of NHL that includes large-cell lymphoma, lymphoblastic lymphoma, and small noncleaved-cell lymphoma. NHL arising in bone is well recognized in adults but is less well characterized and infrequent in children and adolescents. Patients and Methods: We performed a retrospective review of Children's Cancer Group (CCG) studies treating children and adolescents with NHL over a 20-year period (CCG-551, CCG-501, CCG-502, CCG-503, CCG-552, CCG-5911, and CCG-5941) and determined the response and event-free survival (EFS) rates in 31 patients with NHL arising in bone. Results: The patients ranged in age from 3 to 17 years (median, 11 years; mean, 11 years), and 64.5% were male. All 31 (100%) patients achieved complete response. For 31 patients with NHL arising in bone, the product-limit estimated 5-year EFS was 83.8% ± 6.7%. EFS in 17 patients with localized disease (Murphy stages I and II) was 94.1% ± 5.7%, and EFS in 14 patients with disseminated disease (Murphy stage III) was 70.7% ± 12.4% (log-rank P = .10). EFS in 17 patients treated with chemotherapy and radiation was 70.1% ± 11.2%, and EFS in 14 patients treated with chemotherapy without radiation was 100% (P = .03). EFS in 26 patients with histology-directed treatment (LSA2-L2 or ADCOMP for lymphoblastic, other therapy for nonlymphoblastic) was 92.2% ± 5.3%, and in five patients with nonhistology-directed treatment it was 40.0% ± 21.9% (P < .001). Conclusion: NHL arising in bone is a heterogeneous type of NHL that makes up approximately 2.0% of NHL in children and adolescents on CCG studies. Response and survival in this young age group seem superb, with histology-directed treatment protocols without radiation in both localized and disseminated disease.