Rare Causes of Isolated and Progressive Splenic Lesions: Challenges in Differential Diagnosis, Evaluation, and Treatment of Primary Splenic Lymphomas

Laparoscopic Partial Splenectomy May Be Valuable for the Diagnosis of Malignant Lymphoma: A Case Report

Background/Aim

Diagnosing primary splenic malignant lymphoma (PSML) is challenging due to the non-specific nature of splenomegaly, necessitating splenic biopsy for confirmation. However, performing partial splenic resection for diagnostic purposes is an elective procedure due to the risk of major hemorrhage. Despite the longstanding practice of splenectomy over the past few decades, it remains invasive and may result in severe early or late complications. Hence, we present laparoscopic partial splenectomy (LPS) in a patient suspicious of PSML for diagnostic purposes in this study.

Case Report

An 81-year-old woman presented to our hospital with a one-month history of fever and dry cough. Atypical cells had been detected in her peripheral blood nine months ago. However, at that time, a bone marrow examination did not reveal any atypical cells. The laboratory tests revealed a soluble interleukin receptor-2 levels of 4,667 U/dl and atypical cells were also found in peripheral blood. Abdominal computed tomography showed splenomegaly without any other relevant findings. These findings are suspicious of PSML and LPS without vessel ligation was performed and a small fraction of the spleen from the inferior pole measuring 1.8×1.0 cm was resected. The operation lasted for 63 min with minimal estimated blood loss. Histopathological findings were compatible with the diagnosis of diffuse B-cell lymphoma. The postoperative clinical course was uneventful, and splenomegaly demonstrated improvement six months after the operation.

Conclusion

LPS without vessel ligation for biopsy may be valuable for the diagnosis of malignant lymphoma, particularly when there are no swollen lymph nodes, as it offers a less invasive approach.

Comparison of survival outcomes of different treatment modalities for patients with primary splenic diffuse large B cell lymphoma

Primary splenic diffuse large B cell lymphoma (DLBCL) is one of the most common primary tumors in the spleen, while its prevalence is relatively low. Recently, there has been an increase in the incidence rate of primary splenic DLBCL; however, the effectiveness of various treatments for it has not been adequately described previously. The purpose of this study was to compare the effectiveness of various treatments on survival time in primary splenic DLBCL. A total of 347 patients with primary splenic DLBCL were enrolled in The Surveillance, Epidemiology, and End Results (SEER) database. These patients were subsequently divided into four subgroups according to the treatment modalities: non-treatment group (patients who had not received chemotherapy, radiotherapy, or splenectomy, n=19), splenectomy group (patients who had received splenectomy only, n=71), chemotherapy group (patients who had received chemotherapy only, n=95), and the splenectomy combined with chemotherapy group (patients who had received splenectomy and chemotherapy, n=162). The overall survival (OS) and cancer specific survival (CSS) of four treatment groups were evaluated. Compared to the splenectomy group and the non-treatment group, the OS and CSS of the splenectomy combined with chemotherapy group was extremely significantly prolonged (P<0.01). Compared with the chemotherapy group, the OS and CSS of the splenectomy combined with chemotherapy group were longer, but there was no statistical difference (P>0.05). The Cox regression analysis showed that the treatment modality was identified as an independent prognostic factor for primary splenic DLBCL. The landmark analysis shows that the overall cumulative mortality risk was significantly lower in the splenectomy combined with chemotherapy group than in the chemotherapy group within 30 months (P<0.05), and the cancer-specific mortality risk was significantly lower in the splenectomy combined with chemotherapy group than in the chemotherapy group within 19 months (P<0.05). Splenectomy combined with chemotherapy may be the most effective treatment modality for primary splenic DLBCL.

Splenic Micronodular T-Cell/Histiocyte-Rich Large B-Cell Lymphoma: The Corticosteroid Pretreatment Hypothesis

Splenic micronodular T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is derived from diffuse large B-cell lymphoma N.O.S., perhaps with some affinity with nodal THRLBCL. Of note, in contrast with the latter, the only lymph nodes involved in association with the splenic micronodular pattern of the disease are the splenic hilar lymph nodes. The possibility that corticosteroids, when prescribed prior to splenectomy, cause histopathological and functional modulations, apoptosis, necrosis, tissue shrinkage, which may obscure the diagnostic morphological features of this variant lymphoma and cause an underdiagnosis of this condition. The indications for glucocorticoid therapy are either related to the lymphoma itself, or else to other comorbidities, like asthma and autoimmune disorders. We propose that patients with the splenic subset of the disease are likely to have been prescribed corticosteroids prior to histopathologic examination of the involved spleen, causing disparate morphologies. However, a reviewer might accidentally dismiss the corticosteroid pretreatment which is thus overlooked. Apoptosis, induced by corticosteroids, is hypothesized as the major mechanism initiating the histopathological and functional changes in the splenic micronodular variant of the lymphoma.