Terminal pulmonary infections in patients with lung cancer.

To determine the factors that predispose the patient with lung cancer to develop terminal pulmonary infections, we reviewed the case records and autopsy data of 304 patients who died of lung cancer in the Kyushu University Hospital between 1976 and 1990. The incidence of mycobacterial infection was significantly higher among those treated with antineoplastic therapy and corticosteroids (group 3) than in those who received antineoplastic therapy alone (group 2). The incidence of nonbacterial infection did not differ significantly between the two groups. In some group 3 patients, the administration of corticosteroids for relatively short periods (less than one month) led to fatal mycobacterial infection. Among those patients with lymphocytopenia, the incidence of fatal mycobacterial infection was significantly higher in group 3 than in group 2, whereas the incidence of fatal nonbacterial infection was not. In group 3, the incidence of fatal mycobacterial and nonbacterial infections did not differ significantly among those with and without lymphocytopenia. Thus, in patients with lung cancer who were receiving antineoplastic treatment, corticosteroids were more closely associated with the development and exacerbation of mycobacterial infection than was lymphocytopenia. The influence of corticosteroids on the development of nonbacterial infection was not more marked than that of lymphocytopenia. The incidence of common bacterial infections was no higher among those patients who received no antineoplastic treatment or corticosteroid (group 1), group 2, and group 3. Therefore, the local and systemic effects of the lung cancer itself are likely more important in predisposing the patient to bacterial infections than are either antineoplastic agents or corticosteroids.