Pulmonary mycobacteriosis and malignancy presumed activation by irradiation.

It has been widely believed that pulmonary tuberculosis may be activated by irradiation. Although mycobacterial infections are not rare in the immunocompromised host, activation of disease by irradiation has not been described in previous reviews of mycobacterial infections associated with malignancy. This report presents a case of a patient in whom activation of pulmonary infection with mycobacteria of the avium-intracellulare complex was believed to be linked to local irradiation for carcinoma of the breast. The differentiation of pulmonary infection from the effects of irradiation in this setting may be difficult and it is important that irradiation not be blamed for changes that may result from an infectious agent.