The prognostic significance of mediastinal bulk in patients with stage IA-IVB Hodgkin's disease: a report from the Manchester Lymphoma Group.

Three hundred and two previously untreated patients with Stage IA-IVB Hodgkin's disease were reviewed to determine the prognostic significance of mediastinal involvement. Mediastinal bulk disease was defined as either a maximal mediastinal width of 7.5 cm or more, or a ratio of the maximum width of mediastinal disease to the maximum chest diameter of greater than or equal to 0.33, or a ratio of the maximum width of mediastinal disease to the chest diameter at T5-T6 greater than or equal to 0.33, or as an area of mediastinal disease greater than or equal to 100 cm2. Bulk disease outside the chest was defined as a mass of lymph nodes measuring 5 cm or more in any axis. The presence of mediastinal bulk disease was of adverse prognostic significance for remission duration and survival in patients with Stage IA-IIB Hodgkin's disease, but for patients with more advanced disease the effect of mediastinal bulk on remission duration and survival was not statistically significant. The mediastinal bulk variable which most significantly related to prognosis was the ratio of the maximum mediastinal disease to the chest diameter at T5-T6.