The increased morbidity and DALY rates in the working-age population, commonly late diagnosis and unfavorable socio-economic impact of non-Hodgkin lymphomas (NHL) can be considered as key issues of hemato-oncology. Clinico-hematological patterns of primary NHL of the spleen indicate the need of searching the prognosis factors in order to optimize treatment tactics. The objective of the study was distinguishing of clinical and hematological prognosis factors in aggressive NHL of the spleen.

This analytical, cohort study enrolled 45 patients with primary high-grade (HG) NHL of the spleen, who were treated at the Institute of Oncology from Moldova. The diagnosis was proved by cytological, histopathological and immunohistochemical examinations. The types of NHL were assessed according to the Revised 2017 WHO Classification of Tumors of Hematopoietic and Lymphoid Tissues. The patients age ranged between 15-82 years (median - 51.9 years). Stage IV NHL was revealed in 38 (84.6%) cases.

In stage IV NHL with primary involvement of the spleen, the 5-year overall survival (OS) of patients under the age of 50 was 38.5%, above 50 years - 19.8%. The bone marrow (BM) involvement reduced the 5-year OS (24.1%). The average life-span was 23.5 months in cases without leukemic conversion (LC) and 7.4 months in those with LC. When treated with splenectomy and chemotherapy, the 5-year OS attained 47.2%. The 5-year OS accounted 14.0% in stage IV patients treated only with combined therapy.

The post-splenectomy correction of cytopenias persuaded an increase of the OS (54.5%) in cases with refractory cytopenic syndrome. The stage IV, BM dissemination, leukemic conversion, patients age ≥ 50 years, the unfeasibility of performing splenectomy and the resistance of cytopenias to splenectomy may be suggested as the unfavorable prognostic factors in aggressive NHL with primary involvement of the spleen, which should be taken into account in order to optimize treatment options.