Antiperinuclear activity in lung carcinoma patients.

Antiperinuclear factor (APF) might be a specific serum rheumatoid factor directed towards keratohyaline granules. It was found to be present in 40 of 79 (50.6%) patients with primary and in 21 of 36 (58.3%) patients with metastatic lung cancer, compared with 12 of 95 (12.6%) sex- and age-matched normal controls. Additionally, APF frequency and titer correlated well with tumor dissemination, even though no relationship could be shown with histopathological type.