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Working Formulation for Non-Hodgkin Lymphoma

The Working Formulation was developed by the National Cancer Institute in 1982 as a method of translating among the recognized classification systems for non-Hodgkin lymphoma (Rappaport, Dorfman, Lukes and Collins, Kiel, and the British Lymphoma system). The major groups are identified by letters, A - J, and grouped according to prognosis:

most favorable Low Grade A, B, C
Intermediate Grade D, E, F, G
least favorable High Grade H, I, J
Low Grade Intermediate Grade High Grade
Small lymphocytic Follicular large cell Large cell immunoblastic
Follicular small-cleaved cell Diffuse small cleaved cell Lymphoblastic
Follicular mixed small-cleaved and large cell Diffuse mixed small and large cell Small non-cleaved cell (Burkitt and non-Burkitt type)
Diffuse large cell

Cell types categorized as unclassified by the Working Formulation include the nonspecific terms malignant lymphoma, non-Hodgkin lymphoma, diffuse malignant lymphoma, nodular or follicular malignant lymphoma, and cutaneous lymphoma.

Differences in histology refer to differences in the first 3 digits of the ICD-O morphology code.

A simultaneous diagnosis of malignant lymphocytic lymphoma (small cell type) and chronic lymphocytic leukemia (CLL) is coded to CLL.