Cavitary necrobiotic nodule imitating malignant lung disease in a patient without articular manifestations of rheumatoid arthritis.

Pulmonary involvement is a serious complication of rheumatoid arthritis (RA) and may be seen as airway disease, rheumatoid nodules, interstitial lung disease, and pleurisy. However, cavitary rheumatoid nodules without articular manifestations are rare. We describe a male patient presenting with pleurisy and multiple rheumatoid necrobiotic nodules in the absence of arthritis or subcutaneous nodules. One of the nodules was quite large (5 x 8 cm in diameter) and cavitary, imitating bronchial carcinoma radiologically and bronchoscopically. Definite histopathologic diagnosis was obtained by open lung biopsy. The patient was given methylprednisolone and methotrexate, and significant regression was observed in clinical and radiologic findings. He has been followed for 14 months with no articular manifestations yet, receiving 4 mg/d methylprednisolone and 20 mg/wk methotrexate. The diagnosis of rheumatoid pulmonary involvement without articular manifestations can be difficult. Rheumatoid nodules may imitate bronchial carcinoma, or bronchial carcinoma may coexist in RA patients. Open lung biopsy may be necessary for differential diagnosis of pulmonary lesions in RA.