This mixed group of lymphomas is difficult to differentiate histologically, so that pathologists sometimes differ. One system of classification (Rappaport) recognizes four types, each of which can be nodular or diffuse.: (1) Well differentiated lymphocytic. (2) Poorly differentiated lymphocytic. (3) Mixed lymphocytic and histiocytic. (4) Histiocytic (reticulum cell). For the purposes of prognosis they are conveniently divided into: (a) Low grade (small cell lymphocytic and follicular). (b) Intermediate or high grade (diffuse, large cell with small cell). An epidemic of B cell lymphomas is now being reported in California in the wake of the AIDS epidemic, so expect to see them elsewhere.
Non-Hodgkin's lymphoma may present as: (1) An enlarged group or groups of lymph nodes. (2) Symptoms caused by enlarged nodes compressing a patient's trachea and/or his bronchi, his biliary tract, his gut, his urinary system, or his spinal cord. (3) Invasion of these structures. (4) Involvement of his central nervous system. (5) Fever; this is unusual and mild.
NON-HODGKIN'S LYMPHOMA The investigations and differential diagnosis are the same as for Hodgkin's lymphoma (30.4).
STAGING is the same as for Hodgkin's lymphoma, but is less important because 90% of patients present in Stages Three or Four. The prognosis depends more on the histological type, than on the clinical stage.
PROGNOSIS. ''Small cell', high, or intermediate grade lymphomas are more likely to respond favourably. ''Large cell' ones are likely to be unfavourable. Nodular cases have a better prognosis than diffuse ones (most children are diffuse ones).
Untreated, low grade cases survive 7 to 8 years, and intermediate or high grade ones 2 or 3 years.
Here is the percentage of patients in whom you can expect a complete remission, the average remission in months, and the median survival time in months.
If the histology is favourable. Single agent (for example cyclophosphamide): complete remission 65%, average remission in months 35[+], median survival 60[+] months. ''COP': complete remission 80%, remission 35[+] months, median survival 60[+] months.
If the histology is unfavourable. ''CHOP': complete remission 68%, average remission 23 months. ''MOPP or C-MOPP': complete remission 41%, average remission 9 months.
In children, a combined regime will produce a complete remission in 80 to 90%, with a 2 year survival of 60 to 70%.
INDICATIONS. Chemotherapy is the mainstay of treatment, and radiotherapy is no better.
If a patient has asymptomatic low grade lymphocytic lymphoma, he is likely to present in Stages Three or Four. It develops so slowly that no treatment is indicated.
If he has a low grade lymphocytic lymphoma with masses of tumour tissue, anaemia, and leucopenia, treat him. A single-dose regime, for example with cyclophosphamide, is satisfactory. If necessary, transfuse him before starting.
If he has a low grade follicular lymphoma, it is likely to progress more rapidly than the lymphocytic variety. It unlikely to respond to single dose therapy, so give him a combined regime.
If he has a lymphoma of intermediate or high grade type, large cell or small cell, give him chemotherapy.
PREPARATION. Prepare him as in Section 32.2.
CYCLOPHOSPHAMIDE. Give him 1 g to 1.5 g/m['2] intravenously every three weeks up to 6 doses.
''COP'. Give him:
Cyclophosphamide 400 mg/m['2] orally on day one to 5. Or, 1 g to 1.5 g/m['2] intravenously on day 1.
Vincristine (''Oncovin') 1.4 mg/m['2] intravenously on day 1.
Prednisolone 100 mg/m['2] on days 1 to 5.
Repeat this course every 3 weeks up to 6 courses if the response is satisfactory. Then repeat it every 3 months.
Or, try ''CHOP' which is ''COP' plus doxorubicin (''Adriamycin') 50 mg/m['2] intravenously every 3 weeks.
Or, try ''MOPP' as for Hodgkin's lymphoma, or ''C-MOPP' which substitutes cyclophosphamide for ''Mustine'.