Clinical features:
(1) usually affects an older adult
(2) monoarthritis or polyarthritis
(2a) often asymmetric
(2b) often has an explosive onset
(2c) may affect the lower extremities predominantly
(2d) may spare the small joints of the hand and the wrists
(3) negative for rheumatoid factor
(4) resistant to therapy for degenerative arthritis (steroids, NSAIDS, etc)
(5) improves following successful cancer therapy
Cancers associated with this form of arthritis:
(1) non-Hodgkin's lymphoma
(2) acute or chronic leukemia
(3) breast cancer
(4) colon cancer
(5) lung cancer
(6) ovarian cancer
Exclusions:
(1) arthritis associated with metastases to a bone adjacent to a joint
(2) direct tumor invasion into a joint
Differential diagnosis:
(1) adult Still's disease
(2) rheumatoid arthritis or other autoimmune disease
