Presentation
Back pain.
Patient Data
Upper zone predominant centrilobular nodules and irregular 'cysts', sparing the costophrenic angles.
MIPs show the extent of the centrilobular nodules and MinIPs show the elongated irregular branching 'cysts'.
Expanded lytic lesion in the right lateral 8th rib with cortical disruption.
Multiple T2 hyperintense bone lesions: left femoral intertrochanteric region and proximal shaft, pelvis, and bilateral ribs.
Extensive multiple Langerhans cell histiocytosis deposits are demonstrated in the following locations: - Right iliac bone measuring 30 mm x 16 mm with cortical breach posteriorly and endosteal scalloping. - Left iliac bone measuring 24 mm x 14 mm with cortical breach anteriorly. - Left proximal femur contains two lesions with a more superior anterior lesion in the mid intertrochanteric line posteriorly measuring 60 mm (anterior posterior) x 15 mm (transverse) x 20 mm (craniocaudal) in size. There is cortical breach posteromedially with endosteal scalloping. - Left subtrochanteric deposit which is located more anteroinferior to the aforementioned lesion measuring approximately 15 mm (anterior posterior) x 9 mm (transverse) x 23 mm (craniocaudal) in size. There is anterior breach through the anterior subtrochanteric femoral cortex. These lesions are all associated with significant perilesional edema.
Non-compliant for Gd.
Interval marked resolution of the centrilobular nodules.
Enlargement of the irregular, elongated branching 'cysts'.
Case Discussion
Brain MR (not shown) showed absent posterior pituitary bright spot and focal non-enhancing area in the region of the posterior pituitary on dynamic studies, persisting in the delayed phase. No pituitary stalk displacement or floor erosion. Normal infundibular stalk.
Diagnosis of Langerhans cell histiocytosis on was made on bone FNA and confirmed following curettage:
DIAGNOSTIC SUMMARY: FNA Right Ilium: Langerhans cell histiocytosis.
Macroscopic Description: 3 wet fixed slides prepared 3 air-dried slides prepared and needle rinse in RPMI Cell block prepared: Yes FNA performed under CT guidance. 3 passes performed. Note: Specimen sent to Flow Cytometry. Microscopic Description: The specimen is cellular. It contains it contains intermediate sized cells that are dispersed and also present attached to vascular cores; in the background there is necrosis. The lesional cells have enlarged, often cleaved, nuclei with pale, granular chromatin and moderate amounts of pale cytoplasm. There are admixed lymphocytes, plasma cells and also eosinophils. There is a small amount of cellular material in the cell block though most cells appear degenerate. The cells are positive for CD1a, langerin and S100. The morphology and immunophenotype are typical of Langerhans cell histiocytosis. The presence of necrosis is unusual.
DIAGNOSTIC SUMMARY: 1. Left femur curettings: Langerhans cell histiocytosis 2. Left femur curettings: Langerhans cell histiocytosis
Macroscopic Description: Specimen 1: Labeled "curettings left femur", the specimen consists of multiple fragments of bone and blood clot, 30x30x20mm in aggregate, received fresh. Portions for electron microscopy, flow cytometry and cytogenetics, under sterile conditions. Remainder in formalin for histology. All embedded. Block 1A- to 1D. Specimen 2: Labeled "curettings left femur", the specimen consists of multiple pieces of brown tissue admixed with hemorrhagic material, 50x50x10mm in aggregate. All embedded. Block 2A- to 2D. MH Microscopic Description: Specimen 1 and 2: Left femur. The bone reamings contain nodules of Langerhans cell histiocytosis and normal haemopoietic marrow. The nodules have varying cellularity with less cellular areas being associated with fibrosis. The lesional cells that have oval nuclei, with irregular nuclear contours and prominent grooves; there are plentiful admixed eosinophils. Immunohistochemistry shows a classic immunoprofile with strong positive reaction with CD1a, Langerin and S100. There are microscopic areas of necrosis present. Included bone and periosteal fibrous tissue are normal. Immunohistochemistry for BRAF v600E is positive in the tumor cells.
Unable to process the form. Check for errors and try again.