Based on the fact that routine bone marrow biopsy (BMB), as a category of diagnostic procedure for bone and/or bone marrow involvement (BMI) of lymphoma, has quantities of limits such as overlooking of disease and needle tract seeding, while PET/CT, another category of diagnostic procedure, presents satisfactory lesion-detecting performance in extranodal natural killer/T-cell lymphoma (ENKL), we conducted this study focusing on the diagnostic and prognostic performance of PET/CT-based bone/ bone marrow assessment in newly diagnosed ENKL, with the aim of determining the potential of PET/CT to replace routine BMB.
Patients newly diagnosed with ENKL at the Center of Medical Oncology, West China Hospital, from July 2010 to September 2013, were enrolled and underwent staging procedures including clinical, laboratory tests, PET/CT imaging, and unilateral iliac crest BMB. Staging results and BMI-detecting performence (parameters such as sensitivity, specificity, positive/negative predictive value and accuracy) were analyzed. Survivals were compared between subgroups of different PET/CT results or BMB results.
Among a total of 101 patients, 78 were diagnosed as stage I/II and 23 as stage III/IV without the advice of BMB results. No BMB-positive patients were identified in stages I/II, and results of BMB did not alter the stage and treatment choice in any of these patients. The sensitivity and speciﬁcity of focal skeletal PET/CT lesion(s) in assessing BMI were 71.4% and 93.6%, respectively, taking routine BMB as the reference standard. In the analysis of prognostic performance of PET/CT and BMB in advanced-stage patients, OS and PFS of BMB-positive patients were significantly poorer than those of BMB-negative patients (P = 0.0003 and 0.0119, respectively), distinct from PET/CT findings (P = 0.071 and 0.011, respectively).
Based on our results in this study, BMB does not influence staging and treatment in newly diagnosed ENKL, and is not obligatory for early-stage patients undergoing PET/CT. However, in advanced-stage patients, BMB is of great diagnostic value, and even superior prognostic value to PET/CT thus is therefore essential.
Clinical trial identification
This is a retrospective sstudy without the trial protocol number.
All authors have declared no conflicts of interest.