Background: Bone marrow involvement (BM involvement) in lymphoma is a known adverse prognostic factor. Bone marrow biopsy (BMB) is the gold standard for detection of bone marrow involvement but is invasive modality. Positron Emission Tomography with Computed Tomography (PET-CT) scan has the ability to assess bone marrow involvement. We aimed to assess the concordance of PET-CT for BM involvement with BMB. Methods: 75 consecutive newly diagnosed cases of lymphoma were enrolled and were assessed for BM involvement with PET-CT and BMB. Results Of 75 patients, eighteen patients (24%) had BM involvement, with 19% (n=14) detected with BMB, and 13 (17%) with FDG 18 PET CT. There was a concordance rate of 88% amongst PET-CT and BMB. It was 92% in Hodgkin's lymphoma (HL), 71.4% in non-Hodgkin's lymphoma (NHL), and 91% and 70% in high- grade (HG) and low- grade (LG) NHL, respectively. Sensitivity, specificity, PPV, NPV, and accuracy of PET-CT for study population were 69.23%, 93.44%, 69.23%, 93.44%, and 89.19 % respectively. In patients with NHL sensitivity, specificity, NPV, PPV, and accuracy of PET-CT were 54.55%, 94.23%, 66.67%, 90.74%, and 87.30%, respectively; whereas in HL group these were 100%, 88.89% ,75%, 100%, and 91.67%, respectively. Conclusions PET-CT has got a high concordance with bone marrow biopsy in detecting bone marrow involvement with high specificity, NPV and accuracy. A high sensitivity, specificity, NPV and accuracy for detecting bone marrow involvement in patients with HL, aggressive B cell NHL, and T cell NHL was observed but the same parameters were not at par in patient with indolent (low-grade) NHL.

The authors have declared no competing interest.

This study did not receive any funding

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