Add comprehensive articles on Vascular Dementia and Wallerian Degeneration

- Created a detailed article for Vascular Dementia covering key facts, terminology, imaging findings, differential diagnoses, pathology, clinical issues, and diagnostic checklist. - Developed an extensive article on Wallerian Degeneration including key facts, terminology, imaging features, differential diagnoses, pathology, clinical issues, and diagnostic checklist.
2025-10-17 22:11:27 +01:00
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+---
+title: "Granular Cell Tumor"
+docid: "da976b04-85a3-4bf8-ac81-e579f081293e"
+breadcrumbs:
+  - "Brain"
+  - "Diagnosis"
+  - "Anatomy-Based Diagnoses"
+  - "Sella and Pituitary"
+  - "Neoplasms"
+  - "Granular Cell Tumor"
+---
+# KEY FACTS
+
+- ## Terminology
+  
+  
+    - Neoplasms that arise from pituicytes, specialized glial cells of neurohypophysis or infundibulum
+    - Rare low-grade, nonendocrine neoplasms of sellar region
+    - Formerly called pituicytoma; granular cell tumor of neurohypophysis
+    - Part of 2017 WHO spectrum of thyroid transcription factor 1 (TTF-1) expressing pituitary tumors of posterior lobe
+- ## Imaging
+  
+  
+    - Enhancing, well-circumscribed sellar/suprasellar or infundibular mass
+    - 1.5-6.0 cm
+    - CT: Sellar/suprasellar mass with hyperattenuation
+          - Rarely calcification may be present
+    - Best imaging tool: C+ MR with high-resolution imaging through sellar region
+    - Consider granular cell tumor if sellar/suprasellar mass appears separate from anterior pituitary gland
+- ## Top Differential Diagnoses
+  
+  
+    - Pituitary macroadenoma
+    - Lymphocytic hypophysitis
+    - Pituicytoma
+    - Spindle cell oncocytoma
+    - Rathke cleft cyst
+- ## Pathology
+  
+  
+    - WHO grade 1
+- ## Clinical Issues
+  
+  
+    - Commonly asymptomatic (small lesions)
+    - Visual field deficit related to optic chiasm compression is most common presenting feature
+    - Less common symptoms: Panhypopituitarism, galactorrhea, amenorrhea, decreased libido, neuropsychological changes
+    - Typically present in adulthood, 5th-6th decades
+    - Generally benign clinical course
+
+# TERMINOLOGY
+
+- ## Abbreviations
+  
+  
+    - Granular cell tumor (GCT)
+- ## Synonyms
+  
+  
+    - Formerly called pituicytoma; granular cell tumor of neurohypophysis
+- ## Definitions
+  
+  
+    - Neoplasms that arise from pituicytes, specialized glia of neurohypophysis or infundibulum
+    - Rare low-grade, nonendocrine neoplasms of sellar region
+    - Part of 2017 WHO spectrum of thyroid transcription factor1 (TTF-1) expressing pituitary tumors of posterior lobe
+
+# IMAGING
+
+- ## General Features
+  
+  
+    - ### Best diagnostic clue
+      
+      
+          - Enhancing, well-circumscribed sellar/suprasellar or infundibular mass
+    - ### Location
+      
+      
+          - Sellar and suprasellar or infundibular mass
+    - ### Size
+      
+      
+          - 1.5-6.0 cm
+    - ### Morphology
+      
+      
+          - Lobulated and well circumscribed
+- ## CT Findings
+  
+  
+    - ### NECT
+      
+      
+          - Sellar/suprasellar mass with hyperattenuation
+          - Rarely calcification may be present
+- ## MR Findings
+  
+  
+    - ### T1WI
+      
+      
+          - Sellar/suprasellar mass isointense to gray matter
+    - ### T1WI C+
+      
+      
+          - Enhancement may be homogeneous or heterogeneous
+- ## Imaging Recommendations
+  
+  
+    - ### Best imaging tool
+      
+      
+          - C+ MR with high-resolution imaging through sellar region
+
+# DIFFERENTIAL DIAGNOSIS
+
+- [Pituitary Macroadenoma](/document/pituitary-microadenoma/283f3068-d369-4f79-bf01-0f2b82c6e49b)
+    - Sellar and suprasellar enhancing mass
+    - Arises from adenohypophysis
+    - May be indistinguishable
+- [Lymphocytic Hypophysitis](/document/lymphocytic-hypophysitis/f30774c3-cbd0-4ab3-b3d1-e0574106db1f)
+    - May be indistinguishable from macroadenoma
+    - May present as infundibular mass
+    - Typically pregnant or postpartum females
+- [Pituicytoma](/document/pituicytoma/d6e481d5-7742-4354-8dfe-4f04286a709a)
+    - May be intrasellar or suprasellar mass
+    - May be separate from adenohypophysis
+- [Spindle Cell Oncocytoma](/document/spindle-cell-oncocytoma/1557bfb2-8315-4782-9a1e-4e70d6d20c4e)
+    - Imaging mimics macroadenoma
+    - Enhancing sellar and suprasellar mass
+- [Rathke Cleft Cyst](/document/rathke-cleft-cyst/8f1561f7-92a7-485c-a0ae-2e2d5c8c1628)
+    - Nonenhancing cystic sellar &/or suprasellar lesion
+    - Intracystic nodule in up to 75%
+
+# PATHOLOGY
+
+- ## General Features
+  
+  
+    - ### Associated abnormalities
+      
+      
+          - Granular cell tumors have been found in associated with adenomas
+          - Small granular cell clusters have been found in up to 17% of autopsy series
+- ## Staging, Grading, & Classification
+  
+  
+    - WHO grade 1
+- ## Gross Pathologic & Surgical Features
+  
+  
+    - Lobulated, well-circumscribed mass, soft but rubbery
+    - More firm than pituitary adenoma
+- ## Microscopic Features
+  
+  
+    - Densely packed polygonal cells with abundant granular eosinophilic cytoplasm
+    - Electron microscopy: Cytoplasm is filled with phagolysosomes containing electron-dense material and membranous debris
+
+# CLINICAL ISSUES
+
+- ## Presentation
+  
+  
+    - ### Most common signs/symptoms
+      
+      
+          - Commonly asymptomatic (small lesions)
+          - Visual field deficit related to optic chiasm compression
+    - ### Other signs/symptoms
+      
+      
+          - Panhypopituitarism, galactorrhea, amenorrhea, decreased libido, neuropsychological changes
+          - Rarely diabetes insipidus
+- ## Demographics
+  
+  
+    - ### Age
+      
+      
+          - Typically present in adulthood, 5th-6th decades
+    - ### Gender
+      
+      
+          - F:M = 2:1
+- ## Natural History & Prognosis
+  
+  
+    - Rare (~ 150 reported cases)
+    - Generally benign clinical course
+- ## Treatment
+  
+  
+    - Surgical resection
+
+# DIAGNOSTIC CHECKLIST
+
+- ## Image Interpretation Pearls
+  
+  
+    - Consider granular cell tumor if sellar/suprasellar mass appears separate from anterior pituitary gland
+
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