Schwannoma

Schwannoma 

Updated: 08/07/2020

© Jun Wang, MD, PhD

General features
  • Benign nerve sheath tumor arising from differentiated Schwann cells
  • Most commonly 20 - 50 years old
  • Majority are sporadic, may be associated with neurofibromatosis II (NF2) or Carney complex
Clinical presentations
  • Mass with abnormal sensation
  • Commonly in limbs, especially upper limbs, head and neck
  • Deep tumor commonly in posterior mediastinum or retroperitoneum
Pathogenesis
  • Abnormal activation of PI3K, RAS and RAC due to merlin inactivation
Genetic abnormality
  • Loss of function mutation of merlin at 22q12
Morphological features
Marker
  • Positive for S100


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Contents

Pathology notes Jun Wang, MD, PhD 1. General information Frequently discussed syndromes Terms of dermatology Terms of hematology 2. Primary immunodeficiency disorders 3. Hemodynamic abnormalities Shock Thrombosis and embolism Bleeding disorders 4.  Benign blood cell disorders Anemia Benign white cell disorders 5. Hematopoietic neoplasms Lymphoid neoplasms Myeloid neoplasms Histiocytic neoplasms: Langerhans cell histiocytosis 6. Cardiovascular system Pulmonary hypertension Cardiovascular system tumors 7. Respiratory tract tumors 8. Gastrointestinal tract Congenital disorders Infectious gastroenteritis Oral cavity Esophagus Stomach Intestinal tumors Salivary glands Exocrine pancreas and gallbladder 9. Urinary system Kidney masses Lower urinary tract 10. Male reproductive system 11. Female genital tract 12. Breast 13. Endocrine organs Pituitary gland Adrenal gland Thyroid gland Parathyroid gland Endocrine pancreas M
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Anemia

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Myeloid neoplasms

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