Case 120

Provided clinical history

3 year old child with hydrocephalus and slight leptomeningeal enhancement.

Site

Leptomeningeal (arachnoid) biopsy.

Primary image

Intermediate magnification. H&E stain.

Intermediate magnification
Intermediate magnification. H&E stain.

High magnification
Intermediate magnification. H&E stain.

Differential diagnosis

Differential diagnosis
Reactive astrocytosis, meningeal infection, astrocytoma, oligodendroglioma, pilocytic astrocytoma

Additional tests

More history

More history
Diffuse thickening of leptomeninges and progressive spread of the signal alterations along leptomeningeal structures and into the lateral ventricles. The alterations are superficially without contact to the central canal of the spinal cord. No solid mass lesion.

Ask a colleague

Ask a colleague
No primary intraparenchymal or meningeal mass lesion? Think of a diffuse growing glial neoplasm.

Stains

Alcian blue/PAS to Bilirubin Test Result Alcian blue/PAS Dr White would ask why! Alican blue pH 1.0 Dr White would ask why! Alcian blue pH 2.5 Dr White would ask why! Auramine Dr White would ask why! Bielchowsky Dr White would ask why! Bilirubin Dr White would ask why!	Colloidal iron to Fontana-Masson Test Result Colloidal iron Dr White would ask why! Congo red Dr White would ask why! Cresyl violet Dr White would ask why! Dieterle Dr White would ask why! Diff Quik Dr White would ask why! Fontana-Masson Dr White would ask why!	Gallyas to Gremelius Test Result Gallyas Dr White would ask why! Giemsa Dr White would ask why! GMS Dr White would ask why! Gomori's trichrome Dr White would ask why! Gram Dr White would ask why! Gremelius Dr White would ask why!	JMS to Mucicarmine Test Result JMS Dr White would ask why! Jones Dr White would ask why! Kinyoun Dr White would ask why! Luxol fast blue Dr White would ask why! Masson trichrome Dr White would ask why! M-MAS Dr White would ask why! Movat Dr White would ask why! Mucicarmine Dr White would ask why!	Oil red O to Prussian blue Test Result Oil red O Dr White would ask why! Orecein Dr White would ask why! PAS NEGATIVE PASD Dr White would ask why! PASF Dr White would ask why! PTAH Dr White would ask why! Prussian blue Dr White would ask why!	Reticulin to Ziehl-Neelsen Test Result Reticulin Dr White would ask why! Sudan black B Dr White would ask why! Toluidine blue Dr White would ask why! Verhoeff Dr White would ask why! Von Kossa Dr White would ask why! Warthin-Starry Dr White would ask why! Ziehl-Neeslen Dr White would ask why!

IHC

Alpha-1 AT to Cathepsin K Test Result alpha-1 AT Dr White would ask why! ACTH Dr White would ask why! AE1/AE1 NEGATIVE alpha-fetoprotein Dr White would ask why! Alk-I Dr White would ask why! AMACR Dr White would ask why! AR Dr White would ask why! ATRX NO LOSS Beta2-microglobulin Dr White would ask why! B72.3 Dr White would ask why! Beta-catenin Dr White would ask why! BCL2 Dr White would ask why! BCL6 Dr White would ask why! BCLxL Dr White would ask why! C3 comp Dr White would ask why! CA9 Dr White would ask why! Calcitonin Dr White would ask why! Calponin Dr White would ask why! Calretinin Dr White would ask why! CAM5.2 Dr White would ask why! Cathepsin K Dr White would ask why!	CD10 to Chromogranin Test Result CD10 Dr White would ask why! CD117 Dr White would ask why! CD138 Dr White would ask why! CD15 Dr White would ask why! CD1a Dr White would ask why! CD20 Dr White would ask why! CD21 Dr White would ask why! CD23 Dr White would ask why! CD3 Dr White would ask why! CD30 Dr White would ask why! CD31 NEGATIVE CD34 NEGATIVE CD35 Dr White would ask why! CD4 Dr White would ask why! CD43 Dr White would ask why! CD45 (LCA) NEGATIVE CD5 Dr White would ask why! CD56 Dr White would ask why! CD57 Dr White would ask why! CD68 Dr White would ask why! CD7 Dr White would ask why! CD79a Dr White would ask why! CD8 Dr White would ask why! CD99 NEGATIVE CDX2 Dr White would ask why! CEA-m Dr White would ask why! Chromogranin Dr White would ask why!	CK17 to Glypican 3 Test Result CK17 Dr White would ask why! CK19 Dr White would ask why! CK20 Dr White would ask why! CK34betaE12 Dr White would ask why! CK5/6 Dr White would ask why! CK7 Dr White would ask why! CMV Dr White would ask why! c-MYC Dr White would ask why! Cyclin D1 Dr White would ask why! D2-40 Dr White would ask why! Desmin Dr White would ask why! DOG1 Dr White would ask why! EBV Dr White would ask why! EMA Dr White would ask why! ER and PR Dr White would ask why! Factor VIII Dr White would ask why! Factor XIIIa Dr White would ask why! Fascin Dr White would ask why! FH Dr White would ask why! FSH Dr White would ask why! Gastrin Dr White would ask why! GATA3 Dr White would ask why! GCDFP-15 (BRST2) Dr White would ask why! GFAP POSTIVE GH Dr White would ask why! Glucagon Dr White would ask why! Glypican-3 Dr White would ask why!	HBME-1 to IgM Test Result HBME-1 Dr White would ask why! HBV core Dr White would ask why! HBV surface Dr White would ask why! H-caldesmon Dr White would ask why! HCG Dr White would ask why! Helicobacter Dr White would ask why! Hepatocyte Dr White would ask why! HER2/neu Dr White would ask why! HHV-8 Dr White would ask why! HMB-45 Dr White would ask why! HNF1beta Dr White would ask why! HPV Dr White would ask why! HSV-I Dr White would ask why! HSV-II Dr White would ask why! IDH-1 NEGATIVE Inhibin Dr White would ask why! INI1 (BAF47) Dr White would ask why! Insulin Dr White would ask why! Kappa Dr White would ask why! Ki-67 6% Lambda Dr White would ask why! Leu 7 Dr White would ask why! IgA Dr White would ask why! IgG Dr White would ask why! IgM Dr White would ask why!	LH to PDGFR Test Result LH Dr White would ask why! LIN28 Dr White would ask why! Lysozyme Dr White would ask why! mammoglobin Dr White would ask why! MAP2 POSITIVE MCV Dr White would ask why! Melanin A NEGATIVE MHC class I Dr White would ask why! MITF Dr White would ask why! MUM1 Dr White would ask why! Myeloperoxidase Dr White would ask why! MYO D1 Dr White would ask why! Myoglobin Dr White would ask why! Napsin Dr White would ask why! NF Dr White would ask why! NKX3.1 Dr White would ask why! NSE Dr White would ask why! OCT3/4 Dr White would ask why! p16 Dr White would ask why! P501S Dr White would ask why! p53 Dr White would ask why! p57 Dr White would ask why! p63 Dr White would ask why! Pankeratin NEGATIVE PAX2 Dr White would ask why! PAX5 Dr White would ask why! PAX8 Dr White would ask why! PCNA Dr White would ask why! PDGFR Dr White would ask why!	PLAP to WT1 Test Result PLAP Dr White would ask why! PNL-2C Dr White would ask why! Prolactin Dr White would ask why! PSA Dr White would ask why! PSAP Dr White would ask why! RCC Dr White would ask why! S-100 POSITIVE SALL4 Dr White would ask why! Smooth muscle actin Dr White would ask why! Somatostatin Dr White would ask why! STAT6 Dr White would ask why! Synaptophysin NEGATIVE TdT Dr White would ask why! TFE3 Dr White would ask why! TFEB Dr White would ask why! Thyroglobulin Dr White would ask why! Toxoplasma Dr White would ask why! TSH Dr White would ask why! TTF-1 Dr White would ask why! Ubiquitin Dr White would ask why! UCHL1 (PGP9.5) Dr White would ask why! Ulex Europaeus Dr White would ask why! Vimentin POSITIVE VIP Dr White would ask why! VZV Dr White would ask why! WT-1 Dr White would ask why!

Molecular testing

Chromosomal translocations

Translocations Chr 1-10 Test Result t(1;13) PAX7-FKHR Dr White would ask why! t(2,13) PAX3-FKHR Dr White would ask why! t(8;14) MYC-IGH Dr White would ask why! t(9;22) BCR-ABL Dr White would ask why! t(9;22) CHN-EWS Dr White would ask why!	Translocations Chr 11-13 Test Result t(11;14) CCND1-IGH Dr White would ask why! t(11;22) EWS-WT1 Dr White would ask why! t(11;22) FLI1-EWS Dr White would ask why! t(12;15) ETV6-NTRK3 Dr White would ask why! t(12;16) FUS-ATF1 Dr White would ask why! t(12;16) CHOP-TLS Dr White would ask why! t(12;22) EWS-ATF1 Dr White would ask why!	Translocations Chr 14-22 Test Result t(14,18) IGH-BCL2 Dr White would ask why! t(15;17) PML-RARA Dr White would ask why! t(16;21) FUS-ERG Dr White would ask why! t(17;22) COLA1-PDGFB Dr White would ask why! t(21;22) EWS-ERG Dr White would ask why!	Translocations Chr X & Y Test Result t(X;1) PRCC-TFE3 Dr White would ask why! t(X;17) TFE3-ASPL Dr White would ask why! t(X;18) SYT-SSX Dr White would ask why!

Other molecular tests

Molecular tests (A-B) Test Result ALK sequencing Dr White would ask why! B cell clonality Southern / PCR Dr White would ask why! BCL2 PCR Dr White would ask why! BRAF sequencing KIAA1549 (Exon15)-BRAF (Exon9) fusion found	Molecular tests (C-H) Test Result EBV PCR Dr White would ask why! EGRF sequencing Dr White would ask why! H3F3A sequencing NEGATIVE HHV-8 PCR Dr White would ask why!	Molecular tests (I-J) Test Result Identity testing PCR Dr White would ask why! IDH1/2 PCR NEGATIVE JAK2 V617F ARMS Dr White would ask why!	Molecular tests (K-Z) Test Result KIT sequencing Dr White would ask why! LOH 1p/19q PCR LOH 1p/19q present T cell clonality Southern / PCR Dr White would ask why!

Diagnosis

Diagnosis
Disseminated oligodendroglial-like leptomeningeal tumour Comment: DOLN may look very similiar (being histologically indistinguishable) to pilocytic astrocytoma but absence of solid lesion and molecular profile (combined chromosomal 1p loss + presence of a KIAA1549-BRAF fusion) are diagnostic.