Soft Tissue, Rheumatoid nodules

Rheumatoid nodules occur in 20-30% of adults with rheumatoid arthritis and clinically presents as a flesh-coloured, asymptomatic nodule over the extensor areas of the skin and other soft tissue sites.

Microscopic features include multiple nodule subcutaneous granulomas, central necrobiotic collagen, surrounded by palisading spindled and epithelioid histiocytes. Rare neutrophils and eosinophils may be present.