Juvenile Xanthogranuloma
Clinical features Fig 58 – Juvenile Xanthogranuloma –Numerous histiocytes in a loosely cohesive group, is simulating a granulomatous arrangement. Inflammatory cells dispersed in the background (H&E) Immunocytochemistry Modern Techniques of Diagnosis Differential Diagnosis Main points
Langerhans histiocytosis
Clinical features Fig 60 – Langerhans Histiocytosis – Cellular smears with multiple single Langerhans cells. These cells have convoluted nuclei and prominent grooves and fine vesicular chromatin. Eosinophils in the background (H&E) Special Stains and Immunocytochemistry Differential Diagnosis Main Points
IV – HISTIOCYTIC LESIONS
Neuroblastoma NOS
This term includes all sympathetic nervous system tumours of neuroblastic origin. It comprises a wide spectrum of continuous morphological features, ranging from undifferentiated neuroblastoma to ganglioneuroma, depending on the proportion of neuroblastematous (NB) and ganglioneuromatous (GNR) components. Clinical features Fig 43a – Neuroblastoma NOS – Neuroblastoma poorly differentiated- Smears consisting mainly of neuroblastematous component. […]
Peripheral Neuroectodermal tumours (PNET/Ewing´s Sarcoma-)/Ewing Family tumours-EFT
Clinical features Fig 50 – PNET – Discohesive monomorphic small round cells. Tigroid background (Giemsa) Immunocytochemistry Synaptophysin: positive (focal)Chromogranin: in most cases negativeNSE: positive Low diagnostic utility List of CD99 positive tumours Ewing/PNET Alveolar rhabdomyosarcoma Desmoplastic small round-cell tumour Atypical teratoid rhabdoid tumour Synovial sarcoma Mesenchymal chondrosarcoma Merkel cell carcinoma Non-Hodgkin lymphoma Genetic studies Differential […]
Desmoplastic small cell tumour
Clinical features Fig 54 – Desmoplastic small cell tumor –Single and three dimensional groups of monomorphic small round cells (H&E) Immunocytochemistry Genetic studies Differential diagnosis Main points
SMALL ROUND CELL LESIONS
MIXED LESIONS – Synovial sarcoma
Clinical features Fig 40 – Synovial sarcoma- Dispersed stripped nuclei, single spindle-shaped cells and cell-tight tissue fragments (H&E). Remark in the bottom right a cohesive epithelioid Immunocytochemistry Electron microscopy Genetic studies Differential Diagnosis Main points Diagnosis of Synovial sarcomas is easy to achieved, if both epithelial and spindle patterns are present. In monophasic spindle […]
Epithelioid sarcoma
Clinical features Fig 37 – Epithelioid Sarcoma – Aggregates and dispersed cells (Giemsa) Immunocytochemistry Electron microscopy: Genetic studies: Differential Diagnosis Main points
Alveolar soft part sarcoma
Clinical features Cytopathology Histochemistry Immunocytochemistry Electron microscopy Genetic studies Differential Diagnosis Main points