Serum enzymes in head and neck cancer. II. Aliesterase.

Serum aliesterase levels have been estimated in 38 patients with head and neck cancer. The mean value was significantly lower than in controls. The decrease in activity was greater in patients with ulcerative growths and it progressed with advancement in the stage of cancer. With radiotherapy, a progressive and significant increase in serum aliesterase activity was observed. In patients with non-malignant growths the activity was comparable with that in controls.