Osler Institute Pathology Board Review: Electron Microscopy

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Osler Institute Pathology Board Review
Electron Microscopy
EM of Tumors and Tumor-like Entities
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• Neoplasms
• Oncocytoma
• Salivary gland
• Parotid
• Kidney

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• Neoplasms
• Oncocytoma
• Pleomorphic mitochondria
• Lamelliform (plate like) mitochondrial cristae
• Dense bodies in mitochondria

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• Neoplasms
• Plasmacytoma
• Nuclei
• Marginated heterochromatin
• Prominent profiles of rough endoplasmic reticulum
• Immunoglobulin inclusions in RER and nucleus

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• Neoplasms
• Renal Cell Carcinoma
• (conventional type)
• Long microvilli
• Glycogen
• Lipid droplets

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• Neoplasms
• Renal Cell Carcinoma
• Chromophobe Type
• Microvesicles
• Hales colloidal iron positive
• Papillary (chromophil) Type
• Abundant mitochondria

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• Neoplasms
• Seminoma
• Wandering, ropy, nucleolus
• Finely dispersed heterochromatin
• Inconspicuous organelles
• Intercellular junctions

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• Neoplasms
• Squamous cell carcinoma
• Desmosomes
• Tonofilament bundles

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Small Round Cell Tumors
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• Neoplasms
• Small Round Cell Tumors
• Ewings Sarcoma
• Dispersed heterochromatin
• Small nucleolus

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• Neoplasms
• Small Round Cell Tumors
• Ewings Sarcoma
• Large pools of glycogen

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• Neoplasms
• Small Round Cell Tumors
• Rhabdomyosarcoma
• Actin-myosin filaments with Z-band
• Primitive sarcomeres

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• Neoplasms
• Small Round Cell Tumors
• Rhabdomyosarcoma
• Ribosome-filament complexes
• Small primitive junctions
• External lamina

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• Neoplasms
• Small Round Cell Tumors
• Neuroblastoma
• Cell processes
• Secretory granules
• Microtubules
• Neurofilaments

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• Neoplasms
• Small Round Cell Tumors
• Lymphoma (Follicular Center Cell)
• No cell junctions