Aspiration cytopathology of tophaceous gout: a report of 22 patients

Our study demonstrates that MSU crystals are readily detectable under polarization on direct smears with or without staining. FNA cytology can serve as an alternative to core needle biopsy or synovial biopsy in not only confirming a diagnosis of tophaceous gout, but also in eliminating a diagnosis of soft tissue sarcoma in those patients where clinical and/or radiologic features were concerning for malignancy.