A monocyte function test (complement receptor enhancement) to assess the extent of bronchial carcinoma.

A monocyte function test (complement receptor enhancement) was undertaken on 45 patients with suspected bronchial carcinoma in whom this diagnosis was subsequently substantiated. In 38 (84%) complement receptor enhancement was below a range of values previously established for monocytes from 48 healthy control subjects and from 12 patients with non-malignant respiratory diseases. It was found that all 38 patients with reduced complement receptor enhancement had either local or widespread metastases, as determined by the chest radiograph and a variable combination of chest tomography, liver, bone and brain scanning, computed tomography, fibreoptic bronchoscopy, bone marrow aspiration, liver function tests, mediastinoscopy, and surgical assessment, where appropriate. By contrast, at the time of presentation there was no clear relationship between abnormal values in several conventional screening haematological or biochemical tests and the stage of the tumour. These results suggest that complement receptor enhancement might serve as a useful pointer to the extent of the disease, since low values were associated with extension within the chest and very low values were found with widespread metastases.