Relapses, especially at untreated sites, tend to maintain the histologic subtype of the original lesion. Nodular sclerosis and nodular lymphocyte predominance don't fit as readily into this sequence. The latter has an indolent, relapsing course with a good prognosis. In parallel with this progression in subtype is a gradual spread from one lymph node region mostly to contiguous ones. HL originates usually within the neck or mediastinum, only to propagate across the diaphragm along the aortic and iliac lymph nodes and eventually to reach the spleen , liver , and bone marrow .
Additional morbidity comes from the mass affect of the tumor and impaired cell mediated immunity.
To minimize this danger, therapy is tailored to the extent of the disease as determined by a thorough staging. When its results would influence treatment, a staging laparotomy is performed, including splenectomy and biopsies of liver and retroperitoneal lymph nodes.