Clinical and diagnostic challenges in primary splenic lymphomas: when is splenectomy necessary to differentiate SMZL from DLBCL?

Authors

• Natalija Murane The Faculty of Medicine and Life Sciences, University of Latvia, Riga, Latvia 0009-0003-7140-6470
• Jelena Ivanova Centre of Gastroenterology, Hepatology and Nutrition, Pauls Stradiņš Clinical University Hospital, Riga, Latvia
• Alla Sklevska Centre of Gastroenterology, Hepatology and Nutrition, Pauls Stradiņš Clinical University Hospital, Riga, Latvia
• Jekaterina Aleksejeva Centre of Gastroenterology, Hepatology and Nutrition, Pauls Stradiņš Clinical University Hospital, Riga, Latvia
• Viktors Kozirovskis The Faculty of Medicine and Life Sciences, University of Latvia, Riga, Latvia; Center of Oncology, Pauls Stradiņš Clinical University Hospital, Riga, Latvia
• Aldis Pukitis The Faculty of Medicine and Life Sciences, University of Latvia, Riga, Latvia; Centre of Gastroenterology, Hepatology and Nutrition, Pauls Stradiņš Clinical University Hospital, Riga, Latvia
• Polina Zalizko The Faculty of Medicine and Life Sciences, University of Latvia, Riga, Latvia; Centre of Gastroenterology, Hepatology and Nutrition, Pauls Stradiņš Clinical University Hospital, Riga, Latvia

polina.zalizko@lu.lv

Keywords

Abstract

Background: Primary splenic lymphoma (PSL) is a rare form of lymphoproliferative neoplasm, accounting for less than 2% of all lymphomas and approximately 1% of non-Hodgkin lymphomas. While the spleen is often involved in advanced lymphoproliferative disorders, its isolated primary involvement presents significant diagnostic challenges. PSL includes both indolent subtypes, such as splenic marginal zone lymphoma (SMZL), and aggressive forms such as diffuse large B-cell lymphoma (DLBCL).
Case description: We report two cases of PSL with distinct clinical and histological features. The first case involves a 65-year-old male with prior radioiodine treatment for thyroid carcinoma and occupational radiation exposure, who presented with progressive splenomegaly over four years. Splenectomy revealed SMZL characterised by infiltration of small, mature CD20-positive B-cells and a low proliferative index. The patient remains under observation without systemic treatment. The second case concerns a 78-year-old female with a history of breast cancer and hysterectomy, presenting with constitutional symptoms, splenomegaly and diffuse abdominal pain. Imaging demonstrated hypermetabolic splenic lesions and cervical lymphadenopathy. Splenectomy confirmed DLBCL with high Ki-67 index and CD20, BCL6 expression. Systemic chemotherapy with modified rituximab, cyclophosphamide, hydroxydaunorubicin (doxorubicin), vincristine and prednisone (R-CHOP) was initiated.
Conclusion: These cases underscore the diagnostic complexity of PSL, highlighting the importance of histopathological confirmation to distinguish between indolent and aggressive subtypes. In patients with isolated splenomegaly and non-specific systemic symptoms, timely evaluation – including imaging and splenectomy – is critical for accurate diagnosis and appropriate management.

References