Last updated: November 6, 2014
Synonyms: Cancer polyarthritis.
ICD-9 Code: 716.59.
Definition: RA-like polyarthritis in the setting of underlying malignancy.
Etiology: Carcinoma polyarthritis may be secondary to antigenic cross-reactivity between synovium and tumor or be caused by altered cellular and humoral immune mechanisms.
Demographics: Carcinoma polyarthritis occurs most commonly with solid tumors; breast cancer accounts for approximately 80% of cases.
Cardinal Findings: Characteristic features include (1) close temporal relationship of explosive-onset arthritis with malignancy diagnosis (joint symptoms seldom precede malignancy by more than 10 months); (2) late age at onset for inflammatory arthritis; (3) asymmetric joint involvement, often affecting lower extremity joints, with relative sparing of wrists and small joint of hands; (4) absence of rheumatoid nodules and absent or low titer of serum RF. Carcinoma polyarthritis is occasionally mistaken for hypertrophic osteoarthropathy or AOSD (when associated with high fever).
Diagnostic Testing: ESR is often nonspecifically elevated, reflecting the tumor burden. As many as 20% of patients may have low-titer RF or ANA. Synovial biopsy specimens show only nonspecific synovitis. As in RA, bone erosions may develop.
Therapy: Therapy is aimed at alleviating the underlying cancer (tumor resection may improve arthritis). NSAIDs or corticosteroids may be necessary to control arthritis inflammation.
Bennet RM, Ginsberg MH, Thomsen S. Carcinoma polyarthritis. The presenting symptom of an ovarian tumor and association with a platelet activating factor. Arthritis Rheum 1976;19:953–958.PMID:1085629