A reexamination of the relationship between myositis and malignancy

The association between myositis and malignancy has long been appreciated. However, several recent reviews question the validity of this connection and the utility of pursuing an extensive search for occult malignancy in myositis. We report 9 patients fulfilling diagnostic criteria for myositis seen in the past 12 years. In each, a neoplasm was uncovered only in the course of a systematic search or, when initial investigation was deferred, at a later time. Of the 9 patients, 6 had dermatomyositis, 3 polymyositis. In 3 cases, solid tumors were diagnosed concomitantly with the myositis. In the remaining 6 patients, an advanced neoplasm was detected in the course of followup. In retrospect, some of these tumors might have been detected at an earlier and perhaps more treatable stage had a more rigorous initial malignancy search been pursued. Based on this experience, it is imperative that the clinician undertake a more exhaustive search for occult malignancy in patients with myositis than is currently recommended.