Pathogenesis and Molecular Basis
The disease develops due to the abnormal activation of the NF-κB transcription factor. Normally, this protein protects B lymphocytes from apoptosis and stimulates their proliferation, but in pathology, its activity becomes uncontrolled. Causes of this activation include:
- Somatic mutations in cells.
- The influence of Epstein-Barr virus proteins in infected cells.
Impaired apoptosis regulation leads to uncontrolled proliferation of tumor cells.
Gross Pathology
Lymph nodes in Hodgkin lymphoma tend to form dense conglomerates. On cross-section, the tissue appears heterogeneous with yellowish areas of necrosis. Over time, the nodes become drier and firmer due to fibrosis.
Special attention should be paid to the state of the spleen, known as the "porphyry spleen". The organ enlarges, becomes firm, and the cross-section reveals red pulp with characteristic white-yellow foci and mottling.
Clinical Staging
Staging is based on the number of involved lymph node groups, their location relative to the diaphragm, and the presence of extranodal disease:
- Stage I: involvement of a single lymph node region or a single extranodal site.
- Stage II: involvement of two or more lymph node regions on the same side of the diaphragm.
- Stage III: involvement of lymph node regions on both sides of the diaphragm, with possible localized involvement of the spleen.
- Stage IV: diffuse involvement of extranodal organs (liver, bone marrow).
Additionally, modifiers A (absence of systemic symptoms) and B (presence of fever, weight loss, or sweats) are assigned.