The authors describe a child with clinical presentation of acute leukemia and an immunophenotype consistent with precursor B-cell acute lymphoblastic leukemia. However, the lymphoblasts had atypical L3 features and the chromosome rearrangement t(8;22)(q24.1;q11.2) involving the MYC locus. The cytogenetic features in this patient were characteristic of mature B/Burkitt leukemia and led to modulation of therapy. This case highlights the need for timely cytogenetic and molecular studies in the diagnosis of acute leukemia.
To assess the effect of vertebral fractures (VF) and glucocorticoid (GC) exposure on height deficits in children during treatment of acute lymphoblastic leukemia (ALL). Children with ALL treated without cranial radiation therapy (n = 160; median age, 5.1 years; 58.1% male) were followed prospectively for 6 years. Spinal deformity index (SDI) was used to quantify VF status. Baseline height z score ± SD was 0.3 ± 1.2. It fell by 0.5 ± 0.4 in the first 6 months for boys and by 0.4 ± 0.4 in the first 12 months for girls (P < 0.01 for both) and then subsequently recovered. The prevalence of VF peaked at 1 year (17.6%). Among those with VF, median SDI rose from 2 [interquartile range (IQR): 1, 7] at baseline to 8 (IQR: 1, 8) at 1 year. A mixed model for repeated measures showed that height z score declined by 0.13 (95% CI: 0.02 to 0.24; P = 0.02) for each 5-unit increase in SDI during the previous 12 months. Every 10 mg/m2 increase in average daily GC dose (prednisone equivalent) in the previous 12 months was associated with a height z score decrement of 0.26 (95% CI: 0.20 to 0.32; P < 0.01). GC likely plays a major role in the observed height decline during therapy for ALL. Because only a minority of children had VF, fractures could not have contributed significantly to the height deficit in the entire cohort but may have been important among the subset with VF.
Sinus histocytosis with massive lymphadenopathy, or Rosai-Dorfman disease, is a rare histiocytic disorder that typically presents with chronic, self-limiting, cervical lymphadenopathy. We present a case, a diagnostic dilemma for multiple consultation services, of an otherwise well 17-year-old boy without lymphadenopathy who, 8 months after excision of a T9 lytic vertebral lesion and epidural mass that caused cord compression, again presented with cord compression from progressive vertebral disease, recurrent epidural mass, and development of a paraspinal mass and tibial lesion. The excised vertebral and epidural lesions, 2 paraspinal biopsies, and tibial biopsy were interpreted as chronic inflammation until large histiocytes were noted, which were positive for CD68, S100 protein, fascin, and MAC387, and demonstrated characteristic emperipolesis (lymphophagocytosis) that was diagnostic of Rosai-Dorfman disease. This atypical clinical behavior and sites of involvement of multiple bones but not of lymph nodes is unusual and constitutes the aggressive end of the clinical spectrum and a rare cause for cord compression.
The purpose of this article was to determine the incidence and predictors of vertebral fractures (VF) during the 4 years after diagnosis in pediatric acute lymphoblastic leukemia (ALL).Children were enrolled within 30 days of chemotherapy initiation, with incident VF assessed annually on lateral spine radiographs according to the Genant method. Extended Cox models were used to assess the association between incident VF and clinical predictors.A total of 186 children with ALL completed the baseline evaluation (median age, 5.3 years; interquartile range, 3.4-9.7 years; 58% boys). The VF incidence rate was 8.7 per 100 person-years, with a 4-year cumulative incidence of 26.4%. The highest annual incidence occurred at 12 months (16.1%; 95% confidence interval [CI], 11.2-22.7), falling to 2.9% at 4 years (95% CI, 1.1-7.3). Half of the children with incident VF had a moderate or severe VF, and 39% of those with incident VF were asymptomatic. Every 10 mg/m(2) increase in average daily glucocorticoid dose (prednisone equivalents) was associated with a 5.9-fold increased VF risk (95% CI, 3.0-11.8; P < .01). Other predictors of increased VF risk included VF at diagnosis, younger age, and lower spine bone mineral density Z-scores at baseline and each annual assessment.One quarter of children with ALL developed incident VF in the 4 years after diagnosis; most of the VF burden was in the first year. Over one third of children with incident VF were asymptomatic. Discrete clinical predictors of a VF were evident early in the patient's clinical course, including a VF at diagnosis.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)