Karl T. K. Chen

Crush Cytology of Rosai-Dorfman Disease of the Central Nervous System

BACKGROUND Rosai-Dorfman disease (RDD) of the central nervous system (CNS) is rare. There is no previous report on intraoperative crush cytology of this disorder. CASES A 70-year-old man presented with headache and was found to have 2 intracranial extraaxial masses. A 62-year-old man presented with cauda equina syndrome secondary to a mass lesion in the sacral canal. The crush smears, prepared intraoperatively from a small portion of the biopsy specimen in each case, showed scattered lymphoid aggregates in a lighter background with a loose admixture of lymphocytes, plasma cells, usual histiocytes and RDD histiocytes. The RDD histiocytes contained single but sometimes multiple nuclei that were larger and more hyperchromatic than those of the usual histiocytes. Many RDD histiocytes had voluminous, pale pink cytoplasm. Lymphophagocytosis by RDD histiocytes was observed. The findings in the crush smears reflected the histology of the lesions. The lymphophagocytosis and nuclear details in the RDD histiocytes were more visible in the crush smears than in the frozen sections. CONCLUSION Crush cytology appears useful, alone or in conjunction with frozen sections, in the intraoperative diagnosis of CNS RDD.

Crush Cytology of Melanocytoma of the Spinal Cord

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.

Cytodiagnosis of a herniated disk presenting as a soft tissue mass. A case report.

BACKGROUND Extraforaminal disk herniation has been recognized with increasing frequency. When the herniated disk (HD) fragment detaches and migrates away from the spinal column, it can be confused with other space-occupying paraspinal lesions. CASE A 63-year-old female presented with right leg pain and weakness. A magnetic resonance image showed a right psoas muscle mass. Fine needle aspiration biopsy (FNAB) established a diagnosis of HD. CONCLUSION The cytologic appearance of HD is characteristic. When correlated with clinical findings, the diagnosis of HD can be established by FNAB.

Cytology of cystic nephroma: a case report.

BACKGROUND Cystic nephroma is a rare benign multiloculated cystic renal neoplasm that is often confused with multicystic renal cell carcinoma radiographically and cytologically. CASE A 58-year-old woman was incidentally found to have a multiloculated cystic right renal lesion. Cytologic examination of the fluid aspirated from the lesion was reported as highly suspicious for renal cell carcinoma, but a right nephrectomy revealed a cystic nephroma. CONCLUSION Cystic nephroma fluid is characterized by the presence of sparse epithelial cells with moderate nuclear atypia. Conversely, the fluid of multicystic renal cell carcinoma is moderately cellular with no or mild nuclear atypia.

Extraneous cells of hepatic origin in adrenal fine needle aspiration as a diagnostic pitfall: a case report.

BACKGROUND The fine needle aspiration (FNA) cytologic evaluations of most adrenal lesions are straightforward. However, there are diagnostic pitfalls to be avoided. CASE A 34-year-old, pregnant woman was discovered to have an asymptomatic, right upper abdominal mass on ultrasound examination. After delivery, computed tomography-guided FNA showed bland epithelial cells, and a diagnosis of adrenal cortical adenoma was made. However, subsequent resection showed a myelolipoma of the adrenal gland. CONCLUSION This case illustrated 2 cytodiagnostic pitfalls in adrenal fine needle aspirates. First, the myeloid cells characteristic of a myelolipoma were not present in the FNA smears because a large portion of the lesion was composed of fibroadipose tissue. Second, extraneous, benign cells of hepatic origin were misinterpreted as adrenal cortical adenoma cells.

Metastatic carcinoma with myxoid stroma in the salivary gland: A case report

BACKGROUND Most epithelial salivary gland tumors with a myxoid stroma are pleomorphic adenomas. Rare metastatic carcinomas have prominent myxoid stroma and therefore can mimic pleomorphic adenomas cytologically. CASE A 62-year-old man presented with a left canthal tumor. A biopsy and computed tomography revealed an adenocarcinoma of the left ethmoid sinus with medial canthal extension. The patient was treated with tumor resection and chemoradiation. An enlarging, left parotid mass developed that was reported as a pleomorphic adenoma on a fine needle aspirate. However, a parotidectomy showed metastatic adenocarcinoma with a myxoid and fibroblastic stroma in an intraparotid lymph node. CONCLUSION Before concluding cytologically that a biphasic epithelial/myxoid stromal salivary gland lesion is a pleomorphic adenoma, the patients previous malignancies should be reviewed, and the smears should be scrutinizedfor the absence of diffuse epithelial atypia and presence of spindle cells transitional between the 2 tissue phases.

Fine needle aspiration cytology of intraosseous ganglion: a case report.

BACKGROUND Intraosseous ganglia are histologically identical to their soft tissue counterparts. Fine needle aspiration cytology (FNAC) has been described for ganglia of soft tissue, but not for intraosseous ganglia. CASE A 59-year-old woman was incidentally found to have a circumscribed, lytic lesion in the right scapular bone on radiographic studies performed for chronic impingement syndrome. Cytologic examination of the aspirated material from the lesion was reported as nondiagnostic. Open curettage of the lesion with bone grafting was performed. Histologic examination showed an intraosseous ganglion. A review of the FNA smears revealed findings diagnostic of intraosseous ganglion. CONCLUSION The FNAC findings of intraosseous ganglia are similar to those of their soft tissue counterparts. The diagnostic finding is mucoid material with free-floating macrophages. A correct cytologic diagnosis of this entity would ensure proper individualized patient management.