THYMIC CYST
RARE (80 CASES)
MAY BE MORE COMMON THAN THOUGHT
NOT ASSOC. WITH MALIGNANT DEGENERATION OR MG!
3RD BRANCHIAL POUCH DERIVATIVE (WITH INF PARATHYROIDS)
USUALL PRESENT AGE 4-7
PRESENT AS A SWELLING LOW IN THE MID NECK NEAR THE CLAVICLES AND STERNAL NOTCH
Dx: MRI = BEST
PATH = PATHOGNEUMONIC HASSALL’S CORPUSCLES = EPITHELIAL CORDS
MAY BE WITHIN THE CAROTID SHEATH
OFTEN GO MEDIASTINAL!
Rx = WLE