Synovial metastases are a rare occurrence. Only 28 cases have been reported in the literature, I0 of which were diagnosed byfluid cytologic evaluation. We discuss 2 additional cases in which the diagnosis was made byfine-needle aspiration cytologic investigation.
The first case is of a 47-yr-old man with small-cell carcinoma of the lung metastatic to the right knee joint; rhe second is of a 71-vr-old man with non-Hodgkin 's mixed-cell nodular lvmphoma also involving the nght knee joint. The clinical features of these cases are similar to previouslv published instances of secondan. svnovial tumor, namely in regard to
sex distribution (14 male and 16 female patients), age range (13-96 yr, mean 59 yr), and histologic types (adenocarcinorna, 13 cases; squamous-cell carcinoma, 4; lymphoma, 3; renal clear-cell carcinoma. 3: unknown origin, 2: rhabdomyosarcoma. I ; melanoma, I : chordoma, I : pulmomry clear-cell carcinoma. I ; and Ewing 's sarcoma, I ) . The condition usually has poorprognosis. with average patient survival of d mo. Diagn Cytopathol 1996;15:3.3.1-337. 8 19% WIICY-LISS, IN.
The metastatic spread of tumors to the joints and synovium is a rare manifestation of malignant disease. Diagnosis can be made either by cytologic examination of the synovial fluid or by synovial biopsy.'-'6.i8 We report on 2 cases of knee-joint metastasis diagnosed by fine-needle aspiration biopsy (FNAB): first, a small-cell carcinoma in a 47-yr-old patient, and second, a mixed small and large cleaved-cell nodular malignant lymphoma in a 7 1 -yr-old man.
Case Reports Case I
A 47-yr-old black male in previous good health presented with right knee pain and swelling thought to be secondary to a basketball injury. A meniscal tear was shown on arthrogram,