Establishment of Prognosis Nomogram for Primary Splenic Diffuse Large B Cell Lymphoma: A Study Based on SEER Database

Despite being the most common primary tumor of the spleen, in the past, few studies have predicted the prognosis of primary spleen diffuse large B cell lymphoma. This study aimed to establish a nomogram prediction model of overall survival in primary DLBCL of the spleen. We screened out 347 patients with primary splenic DLBCL from surveillance, epidemiology, and end results database. According to the Cox regression results (age, Ann Arbor Stage, splenectomy and chemotherapy was the independent risk factor for primary splenic DLBCL), the nomogram was constructed. We evaluated the predictive ability of nomogram with C-Index (training cohort: 0.719 [0.669-0.769]; validation cohort: 0.711 [0.641-0.781]) and 3-year/5-year receiver operating characteristic area under curve (3-year/5-year ROCAUC, training cohort: 0.731/0.742; validation cohort: 0.721/0.742). Calibratioin plot shows that our predicted values fluctuate around the actual value, indicating good agreement with nomogram. The decision curve analysis (DCA) results showed that our nomogram could benefit more than Ann Arbor Stage for predicts the prognosis of the primary splenic DLBCL. The Kaplan-Meier and landmark analysis showed that a great discrimination between high-risk group and low-risk group (P < 0.05) and indicating that our nomogram has the good ability to identify high-risk patients. In this study, a nomogram prediction model for primary spleen DLBCL was established, which has good ability of prediction and generalization. It can help clinicians carry out individualized treatment measures.