ALK-positive anaplastic large cell lymphoma with primary bone involvement in children.
We describe the clinical, radiologic, and pathologic features of primary bone anaplastic large cell lymphoma (ALCL) in 3 boys. Radiologic imaging showed lytic lesions involving sacrum, femur, or rib. Bone was the only site of disease in 2 cases; an associated partial lymph node was involved in case 3. Differential diagnoses included osteomyelitis and small round cell tumors of childhood, particularly Ewing sarcoma. Preoperatively, ALCL was not a diagnostic consideration in any case. Two cases showed classic large pleomorphic cells; 1 showed a composite pattern with a distinct small cell component and the more typical large cell type. Neoplastic cells in all cases showed strong CD30 and anaplastic lymphoma kinase expression with relatively weak epithelial membrane antigen positivity. Cytotoxic granule protein was expressed in 2 cases. All cases showed unusually strong expression of neuron-specific enolase (NSE). Two patients were disease-free at last follow-up (15 months and 11 years); 1 patient died of disseminated disease within a year of diagnosis. ALCL should be considered a diagnostic possibility when evaluating neoplastic bone lesions in children. Although expression of NSE in ALCL has not been emphasized in the literature, it is worth noting because it may pose a diagnostic pitfall.
Department of Pathology, Oklahoma University Health Sciences Center, Oklahoma City, USA.
Nasir A
NA
Bakshi
Charles W
CW
Ross
William G
WG
Finn
Riccardo
R
Valdez
Robert
R
Ruiz
Khaldoun
K
Koujok
Bertram
B
Schnitzer
D000293:Adolescent; D000077548:Anaplastic Lymphoma Kinase; D001859:Bone Neoplasms / Q000201:enzymology / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D017809:Fatal Outcome; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D017728:Lymphoma, Large-Cell, Anaplastic / Q000201:enzymology / Q000473:pathology*; D008297:Male; D011505:Protein-Tyrosine Kinases / Q000032:analysis*; D020794:Receptor Protein-Tyrosine Kinases
D007770:L-Lactate Dehydrogenase; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases