ABSTRACT
Objective:To analyze the diagnostic and prognostic value of routine bone marrow examination in patients with extranodal NK/T-cell lymphoma (ENKTCL) based on PET-CT staging.Methods:Clinical data of 186 patients who received bone marrow biopsy and bone marrow aspiration in Fujian Medical University Union Hospital from 2013 to 2021 were retrospectively analyzed. All patients were divided into bone marrow biopsy + bone marrow aspiration group ( n=186) and PET-CT + bone marrow biopsy group ( n=139). The sensitivity, specificity, positive and negative predictive values were compared between two groups. The data were analyzed and plotted. Survival analysis was performed using Kaplan-Meier method and log-rank test. Results:In the whole cohort, 45 patients were positive for bone marrow biopsy, and 30 of them were positive for bone marrow aspiration. A total of 141 patients who were negative for bone marrow biopsy also achieved negative results for bone marrow aspiration. A total of 139 patients completed PET-CT staging and bone marrow biopsy. And 30 patients were diagnosed with positive bone marrow by PET-CT, in which 22 of them were confirmed positive by bone marrow biopsy. Among 109 patients diagnosed with negative bone marrow by PET-CT, 5 of them were confirmed positive by bone marrow biopsy. All these cases were classified as stage Ⅳ due to distant metastases. PET-CT had a diagnostic sensitivity of 81.5%, a specificity of 92.9%, a positive predictive value of 73.3%, and a negative predictive value of 95.4%. Among early stage (Ⅰ-Ⅱ stage) patients diagnosed with PET-CT, all of them were negative for bone marrow biopsy (the negative predictive value was 100%). In stage Ⅳ patients ( n=55), the 1-year overall survival of patients with bone marrow involvement by bone marrow biopsy or PET-CT ( n=35) compared with their counterparts with the involvement of other organs ( n=20) was 28.7% vs.42.0% ( P=0.13), and 1-year progression free survival rates was 23.2% vs. 23.3% in ( P=0.94). Conclusions:Routine bone marrow biopsy does not change the original staging of patients with early stage ENKTCL based on PET-CT staging. Advanced stage patients with positive bone marrow biopsy tend to obtain worse prognosis, indicating that bone marrow biopsy still has certain value.