Charlie Herndon

✅ Simple mucinous cyst 🎯 • Benign cavity-forming lesion composed of gastric-type epithelium. • Typically measures greater than 10 millimeters in diameter. • Lined by a single layer of flat cuboidal to columnar epithelium. • Essential negative finding is the absence of ovarian-type stroma.

❌ PanIN: • Microscopic, non-invasive epithelial neoplasm confined to the pancreatic ducts. • Typically measures less than five millimeters in diameter. • Almost always shows gastric differentiation and lacks a grossly visible cyst.

#PathQuiz #Pancreas🍤 57-year-old woman with a 50 mm incidental unilocular cyst in the pancreatic tail. A) Mucinous cystic neoplasm B) Simple mucinous cyst C) IPMN D) PanIN #Pathology #GIPath @IARCWHO

✅ MDM2 amplification 🎯 • Gold standard for diagnosing ALT and well-differentiated liposarcoma • Drives cell cycle progression by inhibiting p53 • Detected via FISH or MDM2 immunohistochemistry • Essential for distinguishing retroperitoneal liposarcoma from large lipomas

❌ PLAG1 rearrangement: • Defining alteration for lipoblastoma • Involves structural changes to chromosome 8q • Results in upregulation of the PLAG1 protein

#PathQuiz 🔬 A) FUS::DDIT3 fusion B) RB1 loss C) PLAG1 rearrangement D) MDM2 amplification #Pathology #SoftTissuePath #MolecularPath Clue in caption 🧐

✅ Oligodendroglioma 🎯 • Honeycomb morphology with chicken-wire vessels • Features classic perineuronal satellitosis • Defined by IDH mutation and 1p/19q codeletion • Strong predilection for the frontal lobes

❌ Astrocytoma, IDH-mutant: • Diffusely infiltrating glial tumor • Often characterized by nuclear ATRX loss • Lacks 1p/19q codeletion

#PathQuiz 🔬🧠#NeuroPath Which finding is expected (and required) for this diagnosis? A) H3 K27M mutation B) ATRX loss C) 1p/19q codeletion D) ZFTA fusion #Pathology #NeuroPath #Glioma