Utility of bone marrow biopsy at diagnosis in pediatric Hodgkin's lymphoma

Bone marrow biopsy is considered essential for the staging and risk-adapted treatment of Hodgkin's lymphoma with unfavorable risk features. We reviewed the cases of pediatric Hodgkin's lymphoma in our institution to determine the impact of bone marrow involvement on treatment, relapse, and survival.

We reviewed the clinical characteristics and outcome of 383 patients treated for Hodgkin's lymphoma at St. Jude Children's Research Hospital between August 1990 and August 2008. The 5-year survival estimates for patients with and without bone marrow involvement were compared.

Of 228 patients who had a bone marrow biopsy at diagnosis, 21 had bone marrow involvement. Bone marrow findings changed the disease stage in only seven patients (3.1%): from IB to IVB (n=1), from IIA (with bulky disease) to IVA (n=1), from IIB to IVB (n=1), and from IIIB to IVB (n=4). One patient's risk assignment changed from intermediate to unfavorable risk without his chemotherapy being altered. No statistically significant difference was observed between patients with stage IV Hodgkin's lymphoma who did (n=21) and did not (n=61) have bone marrow involvement in 5-year relapse-free survival (89.6± 7% versus 73.9±6.1%; P=0.25) or 5-year overall survival (95.2±8.2% versus 87.3±4.9%; P=0.82).

Although bone marrow involvement changed the stage in 3.1% of pediatric Hodgkin's lymphoma patients, it did not change risk-adapted treatment or prognosis. We conclude that bone marrow biopsy need not be performed at diagnosis in patients who have unfavorable risk features, although this finding should be confirmed by larger prospective studies.