Bronchogenic carcinoma may produce signs and symptoms by three different mechanisms: (1) local extension within the lung, (2) metastasis, or (3) by producing systemic effects unrelated to the spread of the tumor.14-16 This brief review will outline some of these systemic effects, which may occasionally represent the first manifestation of the disease. None of these systemic manifestations is specific, in that all may be found in association with malignant lesions of other organs. An arbitrary classification is given in Table 3.
The most frequent metabolic abnormality found in carcinoma of the lung is wasting of the host. The cause of the marked weakness and weight loss which may accompany a small, localized malignancy is not clear. Most recent attention has been directed to a number of rather well-defined endocrine syndromes which may be produced by nonendocrine tumors, of which bronchogenic carcinoma is one of the most frequent.