Changing trends in the incidence of non-Hodgkin's lymphoma in Europe. Biomed Study Group.

Non-Hodgkin's lymphoma (NHL) is not a uniform disease entity, and in order to investigate the reported changes in incidence we have set up a study in seven population-based cancer registries in Europe. The study is designed to look at changes in the incidence of total NHL and disease subgroups using standard definitions and methodology. The registries are based in Leeds, Dijon, Kuopio, Odense, Florence, Eindhoven, and Ragussa. The classification system we have used is based on the REAL classification and has utility for epidemiological studies. We have used it to convert data sets which have utilized both local cases and the ICD-O classification. In order to improve data reproducibility, CLL/LL, myeloma/MGUS, lymphoblastic disease, and Hodgkin's disease have been excluded because of the difficulty in defining incident cases accurately. The preliminary results of this study show that there is still an upward trend in incidence rate and that in Yorkshire this is 3% per annum in total NHL. The subgroups which are increasing are extranodal and nodal peripheral T-cell lymphoma. Similar increases in incidence have been reported for the other registries. We conclude that there is a continued upward trend in incidence of NHL, the causes of which are uncertain.

Prevalence of idiopathic vertebral sclerosis, Zöetermeer, Rotterdam, 1975-1978.

In order better to define the prevalence and characteristics of idiopathic vertebral sclerosis, we evaluated the roentgenograms of 1,391 individuals greater than or equal to 35 years of age) for the presence or absence of idiopathic vertebral sclerosis. One hundred two radiographs showed evidence of idiopathic vertebral sclerosis, a prevalence rate of 5% in this population. For the first time, a roentgenographic classification is offered. These "cases" were then classified into Types I-IV, based on the pattern and location of the sclerosis. The radiologic and demographic characteristics of Type I correlate most closely with previous studies that have investigated the association of vertebral sclerosis with chronic back pain. Women predominated in age-specific classifications; the female-to-male ratio in Type I was 4:1, a reproducible finding in previous studies. The large sample available for study supports the conclusion that this is an accurate estimate of the prevalence rate of idiopathic vertebral sclerosis.