20-48: Rheumatologic Manifestations of Cancer

Rheumatologic syndromes may be the presenting manifestations for a variety of cancers (see eTable 39–1). Dermatomyositis in adults, for example, is often associated with cancer. Hypertrophic pulmonary osteoarthropathy, which is characterized by the triad of polyarthritis, new onset of clubbing, and periosteal new bone formation, is associated with both malignant diseases (eg, lung and intrathoracic cancers) and nonmalignant ones (eg, cyanotic heart disease, cirrhosis, and lung abscess). Cancer-associated polyarthritis is rare, has both oligoarticular and polyarticular forms, and should be considered when “seronegative rheumatoid arthritis” develops abruptly in an elderly patient. Palmar fasciitis manifests as bilateral palmar swelling with finger contractures and may be the first indication of cancer, particularly ovarian carcinoma. Remitting seronegative synovitis with non-pitting edema (“RS3PE”) presents with a symmetric small-joint polyarthritis associated with non-pitting edema of the hands; it can be idiopathic or associated with malignancy. Palpable purpura due to leukocytoclastic vasculitis may be the presenting complaint in myeloproliferative disorders. Hairy cell leukemia can be associated with medium-sized vessel vasculitis such as polyarteritis nodosa. Acute leukemia can produce joint pains that are disproportionately severe in comparison to the minimal swelling and heat that are present. Leukemic arthritis complicates approximately 5% of cases. Rheumatic manifestations of myelodysplastic syndromes include cutaneous vasculitis, lupus-like syndromes, neuropathy, and episodic intense arthritis. Erythromelalgia, a painful warmth and redness of the extremities that (unlike Raynaud) improves with cold exposure or with elevation of the extremity, is often associated with myeloproliferative diseases, particularly essential thrombocythemia.

With the widespread use of immune-checkpoint inhibitors to treat a variety of malignancies, the emergence of immune-related adverse events from these drugs is being recognized. Pneumonitis, colitis, and inflammatory arthritis are common and often can be managed with corticosteroids alone and adjustment of immunotherapy. However, the persistence of some autoimmune conditions despite cessation of cancer treatment, namely inflammatory arthritis, may require long-term immunosuppression.