Radiation therapy in the management of bulky mediastinal Hodgkin's disease.

From July 1981 to July 1985, 20 patients with bulky mediastinal Hodgkin's Disease (maximum mediastinal width divided by the maximum intrathoracic diameter for a mediastinal mass ratio (MMR) greater than 0.33 were treated at Stanford University with definitive radiation therapy alone. The majority of these patients were selected to receive radiation therapy because they had the more favorable characteristics of minimal extralymphatic involvement, mediastinal masses that were superior and central in location, and a MMR less than or equal to 0.50. All 20 patients were laparotomy staged, and 17 received some radiation to the mantle before laparotomy. Seventeen patients had pathologic stage (PS) II disease (13 PS IIA, 4 PS IIB), two had PS IIISA, and one had PS IB. Eleven patients (55%) had extralymphatic involvement. All patients were irradiated to the mantle field using a shrinking field technique (mediastinal dose, 4400 to 5500 cGy, mean 4990 cGy). After completion of the mantle, all patients with good clinical responses received infradiaphragmatic radiation. Treatment complications included two cases of mild radiation pneumonitis, five of hypothyroidism, five of localized Herpes zoster, one of amenorrhea, one of non-Hodgkin's lymphoma, and one of sepsis. Four patients relapsed. All had an intrathoracic component to their failure. All four patients were salvaged with MOP(P) chemotherapy and are currently alive and free of disease. For the entire group, the actuarial freedom from relapse is 80% at 7 years and the survival is 100%. Median follow-up time is 67 months. The authors conclude that radiation therapy alone is effective in the management of selected patients with Hodgkin's disease who have extensive mediastinal involvement, even when the MMR exceeds 1/3.