Carcinomatous neuromyopathyの臨床病理学的研究

A CLINICOPATHOLOGICAL STUDY OF CARCINOMATOUS NEUROMYOPATHY

I．はじめに

　悪性腫瘍と，転移によらない神経および筋の障害との関連性については，最近非常に注目をひいており，種々の観点からの研究成果がだされているが，まだ不明な点も多い。

　Carcinomatous neuromyopathyは，悪性腫瘍に伴つてみられる神経ならびに筋の障害のすべてを包括した意味に使われる場合と，末梢神経および筋の障害に限局して使用される場合とがある。

A histologic study of the 162 human striated mus-cles from the autopsied cases with malignant tumor was done. The controlled group consisted of the 45 specimens from the 36 cases without malignant tu-mor. They were fixed in 10% formalin solution and embedded in paraffin. The microtomized sections, 6 to 10 microns in the thickness, were stained with hematoxylin and eosin for the routin examination.

The main histologic findings were the atrophic change of muscle fibers and the increase of the sarcolemmal nuclei. The clumps or chains of them were frequently observed. There was the degener-ation of muscle fibers also in many specimens. The inflammatory cell infiltration was relatively rare and mild. The changes except for inflammatory cell in-filtration were more frequent in the cases with ma-lignant tumor than without malignant one.

The histologic pattern of muscle involvement of the cases with malignant tumor was 12% in normal, 28% neurogenic, 12% myogenic, 36% simple atrophic, and 20% the other patterns.

The frequency of the atrophic change was almost equal in the cases with malignant tumor and with-out malignant one. The atrophic change of mus-cle fibers is probably due to cachectic and/or ageing process.

In some cases with these abnormal histologic pat-tern of the striated muscles, the clinical manifes-tations of neuromuscular disorders associated with malignant tumor will develop.

The metastatic tumors in striated muscles were revealed in 3 cases of carcinoma of stomach and a case of malignant lymphoma. The metastatic tumor cells proliferated in perimysium without muscle in-volvement in 2 cases of carcinoma of stomach (Fig. 10 & 13), whereas in endomysium with destruction and compression of muscle fibers around them in another case (Fig. 9). In the case of malignant lymphoma, specific cell infiltration was seen in both endomysium and perimysium (Fig. 11 & 12).

In a quadriceps femoris of one case of carcinoma of stomach, many eosinophilic particles were observed in a hypertrophic muscle fiber with vacuolar nuclei containing prominent nucleoli. The particles were elongated along the longitudinal axis of the muscle fibre (Fig. 16).

Central core effects were observed in one specimen of neurogenic pattern and 2 specimens of myogenic pattern (Fig. 14).

In 4 specimens, 2 psoas major and 2 neck muscles, of 4 cases, adjacent several muscle bundles were replaced with proliferated connective tissue contain-ing scattered some atrophic muscle fibers. This change may be a sequel of necrosis of muscle bun-dles due to localized circulatory disorder (Fig. 15).