WHEN one considers the enormous amount of voluntary muscle tissue that comprises the human body, one is amazed at the relative infrequency of neoplastic disease in this tissue. A search of the medical literature reveals that only 208 cases of rhabdomyosarcoma have been reported.1 This is exclusive of a series of 51 myocardial tumors which included both rhabdomyoma and rhabdomyosarcoma2 and of cases of rhabdomyosarcoma of the vagina in children.
INCIDENCE AND SITE OF ORIGIN
In the 208 proved cases of rhabdomyosarcoma the following distribution was reported: testis, 17; orbit (eye), 19; bladder, 9; prostate, 18; spermatic cord, 1; uterus, 22; epididymis, 1, and skeletal muscle, 121. Stout1h has listed the rhabdomyosarcomas of skeletal muscles and given their locations as follows in his monograph: lower extremity, 52 cases (thigh, 33; leg, 18; foot, 1); upper extremity, 17 cases (arm, 9; forearm, 7; hand, 1); trunk, 31 cases (back,