Radiation Therapy for Rhabdomyosarcoma

Abstract

The treatment of rhabdomyosarcoma has been the subject of considerable discussion (4). Radical surgical extirpation of the primary tumor is usually attempted, occasionally followed by irradiation. Unfortunately, widespread metastases usually appear early in the course of the disease and lead to a rapid death; this makes accurate evaluation of any therapeutic regime difficult. Rhabdomyosarcoma of the orbit, the most common primary orbital malignant tumor of childhood (8), offers a unique opportunity to study the role of surgery, radiotherapy, and chemotherapy in treatment of this tumor because disease in this site tends to remain localized, often for periods of months (1). Despite an absence of time-dose data, surgeons have dismissed irradiation in attempts at curative treatment (3, 8, 9). Lederman claims the disease is radiosensitive, but not radiocurable, owing to its prompt local recurrence (7). Present Material We have reviewed the records of 17 patients with a diagnosis of orbital rhabdomyosarcoma referred to the Division of Radiotherapy of the Columbia-Presbyterian Medical Center from January 1952 to December 1966. Fourteen were classified as embryonal in type, two were called undifferentiated, and one was an alveolar rhabdomyosarcoma. The sex ratio was 8 females to 9 males. Age at presentation has ranged from six months to thirteen years (Table I). The most common initial sign of disease was a mass appearing in 16 patients; proptosis as present in 10. The initial site of the orbital tumor was specified in 14 cases, 7 in each eye. The inner aspect of the upper lid was involved 9 times, the lower inner aspect twice. One lesion arose in each of the following sites: mid-upper lid, mid-lower lid, and upper outer lid. In no patient was bilateral orbital involvement either a presenting symptom or a later development. To better assess the effect of local treatment, the cases have been divided into three groups according to the stage of disease at the time of initiation of radiotherapy. These groups are: (a) generalized disease; (b) locally recurrent disease after surgery; (c) localized disease treated with primary, definitive radiotherapy after biopsy. Three patients presented with signs and symptoms of generalized disease, and all succumbed. Two received only palliative treatment. Local orbital tumor control was achieved in one patient until death two years after the administration of 5,500 R in thirty-six days (Fig. 1). In 14 patients, only localized disease was demonstrable. Biopsy was followed by immediate exenteration in 9. In only 1 of the 9 was exenteration followed by “prophylactic” irradiation (3,600 R/twenty days) and chemotherapy (actinomycin D); he remains free of disease forty-eight months later. Exenteration was deemed incomplete in 2 patients. One of these 2 died during subsequent treatment as a result of chemotherapy complication; the other was treated with radiation and is alive without disease four years later (Fig. 2).