The prognostic influence of mediastinal bulk in pathological stage IIA Hodgkin's disease treated initially with...

The response to treatment and survival has been assessed in 61 patients with pathological Stage IIA Hodgkin's disease with mediastinal involvement who were treated initially by supradiaphragmatic radiotherapy alone. Although 57 (93%) obtained complete remission, 29 have relapsed giving a total of 33 (54%) treatment failures. The percentage of patients actuarially disease free at 5 years is 44% although overall survival is 90%. The "bulk" of the mediastinal disease was assessed on a plain chest X-ray by measurement of the widest diameter of the mass compared to thoracic diameters at various levels as well as by determination of the area of the mass. The ratio of the widest diameter of the mass to the widest internal thoracic diameter provided the greatest prognostic information. Patients with a ratio greater than 0.33 (30% of total) had an actuarial disease-free survival of 24% at 5 years compared to 54% in patients with smaller mediastinal masses (P less than 0.05). Mediastinal bulk was not correlated with histological grade. Patients with the largest mediastinal masses (ratio greater than 0.37) (10% of total) have a lesser survival, but in the remainder, measurement of the mediastinal mass did not predict survival, indicative of the excellent salvage rate with subsequent chemotherapy. The implication of these findings for the treatment of stage IIA Hodgkin's disease with mediastinal involvement is discussed.