Lower Back Pain As the Initial Manifestation of Primary Follicular B-cell Non-Hodgkin Lymphoma of the Bone Marrow: A Case Report

Follicular B-cell non-Hodgkin lymphoma (B-NHL) is a malignant disease of the lymphatic system that primarily affects the lymph nodes.The primary presentation of follicular B-NHL in the bone is extremely rare.The patient, a 53-year-old woman, developed non-radiating lower back pain at the age of 52.Diagnostic evaluation via magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) revealed a solid intraosseous mass in the L3 vertebral body, an L2 compression fracture, and extensive metastatic disease involving the ribs, vertebral bodies, ilium, and cranial vault.Three months after the onset of lower back pain, a CT-guided biopsy of the ilium confirmed the presence of follicular B-NHL lymphoma cells.These cells tested positive for CD10, BCL6, and BCL2, as well as for the minimal residual disease marker t(14;18).Cranial MRI showed osseous lesions in the cranial vault but no intra-axial lesions.No extraosseous metastases were detected.Risk stratification indicated stage IVA, Follicular Lymphoma International Prognostic Index (FLIPI): 4-5, and FLIPI2: 3. Six cycles (one per month) of therapy with rituximab, bendamustine, and intravenous immunoglobulins proved ineffective after five months.Twelve months after symptom onset, the lymphoma progressed and transformed into diffuse large B-cell lymphoma (DLBCL).Various attempts to treat the DLBCL were also unsuccessful.Twenty months after the onset of lower back pain, the patient died of sepsis.In summary, this case demonstrates that follicular B-NHL can initially involve only the bones and manifest solely as lumbar back pain.In summary, this case demonstrates that follicular B-NHL can initially involve only the bones and manifest solely as lumbar back pain.Despite chemotherapy, symptoms may worsen, and B-NHL may transform into fatal DLBCL.