Crush cytology of melanocytoma of the spinal cord. A case report

BACKGROUND: Primary melanocytic neoplasms of the central nervous system are rare. There is no previous report on the intraoperative crush cytology of these neoplasms. CASE: A melanocytoma occurred in a 65-year-old woman who presented with back pain, and weakness and numbness of the right lower extremity. Magnetic resonance imaging revealed an enhancing mass in the conus medullaris. The tumor was subtotally removed. Crush smears revealed dispersed and perivascular aggregates of monotonous oval or spindle tumor cells with round or oval, uniform nuclei; small nucleoli; and long cytoplasmic processes. Some tumor cells contained fine or coarse cytoplasmic brown pigments. The pigments were easier to discern in the crush smears than in the frozen sections. CONCLUSION: Crush cytology appears to be helpful, alone or in conjunction with frozen sections, in the intraoperative diagnosis of meningeal melanocytoma.