Diagnosis and staging

According to the European Society for Medical Oncology (ESMO), the diagnosis of Diffuse Large B-Cell Lymphoma (DLBCL) should include an excision biopsy to assess the nodal architecture and provide adequate specimen for phenotypic and molecular studies. Needle core biopsy is only recommended in patients in whom a surgical approach is not possible or advised.¹ Immunophenotypic investigations should provide a morphological diagnosis of DLBCL using immunohistochemistry, flow cytometry or both. EBER-1 staining is recommended to identify Epstein-Barr Virus (EBV). Diagnosis should be carried out according to the current World Health Organization (WHO) classification.^1,2 Hepatitis B virus testing is included due to the risk of reactivation prior to treatment with CD20 monoclonal antibodies. Hepatitis C testing is required in high-risk patients and patients with splenic Marginal Zone Lymphoma.³

Staging is done according to the Ann Arbor classification system (Table 1), although a new staging system has been proposed but has not yet been validated.⁴ 

 The International Prognostic Index (IPI) and age-adjusted IPI (aaIPI) should also be calculated for prognostic purposes (Table 2).