Aspiration biopsy of osseous metastasis of retroperitoneal paraganglioma. Report of a case with cytologic features and differential diagnostic considerations.
BACKGROUND
Paragangliomas are uncommon tumors, only 10% of which are malignant, as evidenced by metastatic disease. It is rare for paraganglioma to present with symptomatic osseous metastases.


METHODS
A retroperitoneal paraganglioma presented in a 52-year-old man as painful metastases in the rib and vertebrae. Fine needle aspiration (FNA) of a lumbar vertebral lesion showed cells arranged singly and in loose clusters with fragile, vacuolated or finely granular cytoplasm, marked anisonucleosis and mitoses. Rare zellballen-type structures and intranuclear inclusions were present. Immunohistochemical studies of a subsequent FNA core biopsy of the retroperitoneal mass showed strong immunoreactivity with chromogranin and negative staining for keratin; that was helpful in differentiating this tumor from others in the differential diagnosis.


CONCLUSIONS
The cytologic diagnosis of paraganglioma is difficult as these tumors exhibit a plethora of features that overlap those of many other neoplasms. The diagnosis can be confirmed with appropriate immunohistochemical studies of corresponding core biopsies.
Department of Pathology, Baylor College of Medicine and Methodist Hospital, Houston, Texas, USA.
K J
KJ
Absher
D A
DA
Witte
L D
LD
Truong
I
I
Ramzy
D R
DR
Mody
M L
ML
Ostrowski
D014408:Biomarkers, Tumor / Q000378:metabolism; D001707:Biopsy, Needle; D001859:Bone Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology* / Q000556:secondary*; D002277:Carcinoma / Q000175:diagnosis; D002864:Chromogranins / Q000378:metabolism; D003937:Diagnosis, Differential; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008545:Melanoma / Q000175:diagnosis; D008875:Middle Aged; D010235:Paraganglioma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology* / Q000556:secondary*; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D012509:Sarcoma / Q000175:diagnosis; D014057:Tomography, X-Ray Computed
D014408:Biomarkers, Tumor; D002864:Chromogranins