[Non Hodgkin lymphoma in the North-East Bosnia--changes in biological aggressiveness and primary presentation of the disease]

Abstract

Introduction: NHL are the group of lymphoproliferative neoplasms which incidence is in constant increase. The aim of the paper is the analysis of the immunophenotypes, clinical distribution and ways of primary presentation and biological aggressiveness of NHL in the North-East Bosnia. It especially illustrates the post war period from 1998 to 2002.

Methods: Two hundred and twenty-eight patients with pathohistologically proved NHL are analysed in the paper. The tested group consisted of 142 patients with diagnosed NHL in the period between 1998 and 2002, and the control group consisted of 86 patients whose NHL was proved in the period between 1987 and 1991. These factors were analysed: immunophenotype NHL by immunohistochemical method of indirect three-stage immunoperoxidase with streptovidin, the type of NHL, the degree of biological aggressiveness of NHL, the way of primary presentation and the clinical phases of distribution of the disease according to the age, sex, profession and the habitat (urban or rural) of the patients. The prevalence and the incidence of the disease in the region of the North-East Bosnia was determined. The statistical analyses of the date was performed by the average values, standard deviations and chi2 test.

Results: The total number of patients with NHL in the North-East Bosnia was quite bigger in the test group than in the control group with the incidence of 2.6/100,000 inhabitants in 1989, and 6.91/100,000 inhabitants in 2002. There were 80 men (56%) and 62 women (44%) in the test group, and 55 men (64%) and 31 women (36%) in the control group. The average age of the patients was 55.78 +/- -15.1 years. Statistically significant decrease of patients was noticed in the groups of industrial and agricultural workers in the test group comparing with the control group (9% against 15% and 4% against 19%, p < 0.005). At the same time the significant increase of the number of patients was found in the test group from the industrial regions of Lukavac (15 against 4 patients, p < 0.005), Tuzla (49 against 19 patients, p < 0.005) and Zivinice (14 against 3 patients, p < 0.005). Diffuse Large Cell Lymphoma (DLCL) was dominant in the test group with total of 73 patients (51%), and Small Cell Lymphoma was dominant in the control group with total of 33 patients (38%). Statistically significant increase of both DLCL and MALT lymphoma is found in the test group (p < 0.025), and the most frequent were patients with IV-B (18%), I-AE (15%) and II-BE (12%) clinical stadium, while in the control group the most frequent number of patients was in the clinical studia III-B (19%), II-B (14%) and IV-B (14%). The most prevalent stadium in both groups was B fenotype with 94% of cases in the test and 93% in the control group. The aggressive lymphomas are predominant in the test group (62%) while the indolent ones are predominant in the control group (64%). In both groups the most of the patients were with nodal primary presentation (51%). In the test group there was a significant increase of aggressive lymphoma in both men and women (p < 0.01).

Discussion: In recent years, all NHL studies have shown an increase of the incidence in patients, especially in older age while the increase is not found only in infants. In our study the highest percentage of the incidence of NHL occurs in patients who are 55 and older that exactly matches the literature date. There is an increase of extranodal primary presentation (28%) in test group in comparison with the control group (18%). The distribution of the patients is not significantly different from the findings of the European Oncology Association from 2003 where it says that there are 54% of patients with primary nodal presentation, 34% of them with primary extranodal presentation and 12% combination of the two presentations. Recently, the most frequent presentation worldwide is in stomach, which is also proven in our research. In the test group the number of MALT and DLCL lymphoma located in stomach is in increase. In the last few years the dominant type of NHL worldwide is DLCL. Therefore the significant increase of the patients with this disease is noticed in our test group. The continuous increase of patients with aggressive NHL in the recent years has been noticed especially Lukavac, Tuzla and Zivinice. These are the regions where the electric plant and the chemical industry factories are located.

Conclusion: The incidence of NHL in the region of the North East Bosnia follows the world trend of the general increase of the NHL incidence including the significant increase in number of aggressive lymphoma. The frequency of DLCL and MALT lymphoma is evidently in increase. The significant changes in primary presentation of the disease have not been noticed. B phenotype of NHL is predominant in both periods of testing.