Non-Hodgkin's Lymphoma in Japan Trial for TNM Clinical Staging and Histological Classification

Five hundred fifty-one new cases of non-Hodgkin's lymphoma were retrospectively studied with reference to histological classification, age incidence and survival. When examined according to the modified Rappaport classification, nodular lymphoma accounted for 14.9%, while diffuse lymphoma accounted for 82.9%. However, the frequency of nodular lymphoma differed among lymphomas of nodal, Waldeyer's and extranodal origin. Malignant lymphomas composed of large lymphoid cells were found to be common in Japan compared with Western countries, diffuse large lymphoid (DLL) lymphomas accounting for 47.4%, and nodular large lymphoid (NLL) lymphomas for 8.3%. The five-year survival rate according to histological classification was high in malignant lymphoma, diffuse well-differentiated lymphocytic (DWDL, 72%), nodular poorly differentiated lymphocytic (NPDL, 60%), nodular mixed PDL and large lymphoid (Nmix, 45%) and diffuse mixed PDL and large lymphoid (Dmix, 54%) lymphoma, but low in diffuse lymphoblastic (DLB, 10%), diffuse pleomorphic (Dpleo, 25%) and diffuse poorly differentiated lymphocytic (DPDL, 22%) lymphoma. The relationship between five-year survival and stage seemed to be close, although the last three types listed above were often found in advanced stages. The frequency of leukemic change was high in DLB (40%), DPDL (25%) and NPDL (20%) lymphoma. Radiation therapy proved effective in stages I and II cases, especially in Waldeyer's lymphoma. Chemotherapy provided better results in stages III and IV, although the rate of induction of complete remission was still unfavorable. The results of therapy were most favorable in patients given a combination of radiation therapy and chemotherapy.