Diagnostic Accuracy of Positron Emission Tomography-Computed Tomography (PET-CT Scan) In Detecting Bone Marrow Involvement in Patients with Diffuse Large B cell Lymphoma

Objective: To evaluate the diagnostic accuracy of positron emission tomography combined with CT scan (PET-CT Scan) in detecting bone marrow involvement in patients with diffuse large B-cell lymphoma, keeping bone marrow biopsy as gold standard. Methodology: From November 2017 to May 2018, a cross sectional validation study was carried out at the Aga Khan University in Karachi Department of Oncology's Section of Clinical Hematology. The study comprised a total of 112 patients who were identified as having diffuse large B cell lymphoma after a lymph node was implicated was histopathologically examined. All patients had a PET-CT scan and bone marrow biopsy technique as part of the staging workup. With bone marrow biopsy acting as the gold standard, the diagnostic efficacy of a PET-CT scan for identifying bone marrow involvement was evaluated. Results: Of 112 patients, there were 71(63.39%) males and 41(36.61%) females. The mean age was 45.09±17.36 years. The mean duration of diagnosis was 17.19±6.02 days. Through biopsy, bone marrow involvement was identified in 40 (35.7%) cases. Through a PET-CT scan, bone marrow involvement was identified in 47 (41.9%) cases. The PET- CT scan in comparison with bone marrow biopsy for detecting bone marrow involvement in patients with DLBCL had a sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of 95%, 87.7%, 80.85%, 96.92% and 90.18% respectively. Conclusion: PET-CT scan can accurately detect bone marrow involvement in patients with DLBCL so it can be used in most patients instead of invasive bone marrow biopsy procedure for staging of DLBCL patients.