Lymphomas are neoplasms of B-lymphocytic (75% of cases) or T-lymphocytic (20% of cases) origin. It is now appreciated that the various sub-types of disease represent counterparts of the normal pathways of lymphoid differentiation and transformation, from resting cells to fully transformed and activated lymphoid cells. The large cell lymphomas represent a group of neoplasms, formerly grouped together and termed 'histiocytic lymphoma' which represent transformed lymphocytes, of T- or B-cell derivation. Within the Working Formulation for Clinical Usage, a recently proposed translational tool, these lymphomas fall within the 'Intermediate' or 'High-grade' disease categories. The initial evaluation of a patient with large-cell lymphoma must include a formal staging procedure, in order to ascertain the precise extent of disease, so that appropriate therapeutic decisions may be made. This evaluation is also useful for defining all sites of lymphomatous disease, so that the results of any given therapeutic intervention can be accurately assessed. For the patient with localized, stage I disease, one option would be to take the patient to formal staging laparotomy, in order to attempt to prove the presence of pathologic Stage I disease. In this instance, wide-field radiotherapy may be employed, with the chance of achieving long-term, disease-free survival of approximately 70%. Alternatively, the patient may be staged less aggressively, and given combination chemotherapy, which is also effective in low-stage disease. In patients with Stage II, III or IV large-cell lymphoma, multi-agent chemotherapy is the expected treatment modality, although some controversy currently exists regarding the optimal regimen(s).(ABSTRACT TRUNCATED AT 250 WORDS)