Quantitative analysis of voluntary muscles from routine autopsy material with special reference to the problem of remote carcinomatous changes ("neuromyopathy").

Specimens from the deltoid muscle of 210 randomly selected autopsy cases without previous clinical evidence of primary neuromuscular impairment were examined with regard to the influence of extramuscular diseases on voluntary muscle. Differences between malignant tumours and other disorders were of special interest with respect to the question of the possible existence of a remote effect of cancer on skeletal muscle. The number of central nuclei within muscle fibre cross sections was considered as the most simple parameter for myopathic reaction. Atrophic fibre changes were examined quantitatively by measurement of the orthogonal fibre diameters and calculating the variation of fibre size. In addition, a semi-quantitative histological evaluation of the muscles was performed. While tumor cases did not show a significant difference from the remainder with respect to myopathic changes, they did display a significant difference with regard to scattered and small-group fibre atrophy. The reasons for the muscular changes are discussed. From the present investigation the changes seem to be due chiefly to metabolic impairment and wasting. No signs for a specific carcinotoxic effect on skeletal muscles could be demonstrated.