Report of the Committee on Hodgkin's Disease Staging Classification.

Since the Rye classification for staging was produced in 1965, the significance of 2 important observations with major impact on staging has been appreciated. First, extralymphatic disease, if localized and related to adjacent lymph node disease, does not adversely affect the survival of patients. Patients with localized extralymphatic disease do as well as comparable patients of the same stage without extralymphatic spread. Secondly, laparotomy with splenectomy has been introduced as a method of obtaining more information on disease extent in the abdominal region. Thus, it has become necessary to reconsider the Rye classification and to recommend a modified scheme. Staging has 2 aims. The first is to facilitate communication and exchange information. This can be done only at the expense of a loss of some information, as it is necessary to condense in one number a considerable amount of data. Furthermore, intercomparison demands that all the staging procedures performed should be as similar as possible in each center to avoid bias in staging and interpretation of the therapeutic results. The second aim is to provide guidance of prognosis and to assist in therapeutic decisions. This latter aim is best achieved when the greatest amount of information is collected for each patient. It has been recognized that a single staging procedure cannot achieve these 2 purposes. For instance, it is obvious that laparotomy and splenectomy provide much information, but these procedures cannot yet be recommended for every patient. A staging classification based on information obtained by histopathological examination of the spleen and lymph nodes obtained at laparotomy cannot be compared with another done without such vigorous exploration. As a result, unless these factors are taken into account, either intercomparisons of therapeutic results become virtually impossible or much valuable information is excluded from the staging method. Therefore, 2 systems of classifications are presented. Clinical staging (CS). while recognized as incomplete, is easily performed and should be reproducible from one center to another. The second, called pathological staging (PS), takes into account all the extrapathological data obtained from vigorous staging procedures and has a higher degree of precision but is restricted in its application to relatively few centers.