[Malignant non-Hodgkin's lymphoma of the joint. Report of two cases, review of the literature and problems of classification].

This paper gives a survey of malignant Non-Hodgkin lymphomas (NHL) of joints. Primary and secondary malignant lymphomas of joints are rare. Our analysis of 6 years', new entries in the lymph node register in Kiel, covering 37.367 cases of malignant lymphomas, revealed only 20 cases (0.05%) with infiltration of joints. Slightly more men than women (1.18:1) are actually affected by articular lymphomas. In addition to 34 articular lymphomas of joints described in the literature between 1974 and 1992, we analyse 2 cases seen in our own institute and the 20 cases taken from the Kiel lymph node register. The peak incidence is between 40 and 60 years of age. One of our own cases, a woman of 92, is the oldest person ever affected. The most frequent localizations of NHLs are the knee, hip, and shoulder joints, with low-grade lymphomas predominating. Osteolytic lesions on radiographs are of decisive clinical and diagnostic significance for malignant articular lymphomas with affected bones. Lymphomas of joints are treated almost exclusively by radiation and chemotherapy, and sometimes a combination of both. Decisive prognostic significance attaches to the grade of malignancy and the fact of primary or secondary infiltration of the synovium and of the bone. The average survival time for patients with low-grade NHLs is 19 months with infiltration of the synovium and 27 months with infiltration of joint forming bones only, whereas the average survival time for patients high-grade lymphomas is 8 months with infiltration of the synovium and 11 months with infiltration only of joint-forming bones.(ABSTRACT TRUNCATED AT 250 WORDS)