Navigating diagnostic challenges: A rare lymphoma mimics myositis. This case report highlights a challenging case of extranodal NK/T cell lymphoma initially misdiagnosed as myositis, emphasizing the complexities in diagnosis due to overlapping imaging features on MRI and FDG PET. The patient presented with systemic symptoms and calf muscle swelling, prompting imaging studies that revealed diffuse muscle involvement. The initial diagnostic process was complicated by negative myositis markers and an inconclusive biopsy. Post-amputation findings ultimately confirmed lymphoma with EBV positivity. The appearance in both MRI and FDG PET complicated the diagnostic process, underscoring the importance of considering lymphoma in cases of muscle-related symptoms to prevent delays in appropriate management. The systemic symptoms along with muscle involvement presented initially led the physicians to the wrong conclusion, which highlights the need to consider such rare diagnosis in similar situations. Ultimately, this case contributes to the understanding of the diagnostic challenges associated with extranodal NK/T cell lymphoma and emphasizes the significance of peripheral band-like features in imaging studies. It also provides insight into the importance of awareness and early suspicion for this rare disease, helping to reduce the time to proper management.
This case report fits well within the scope of Skeletal Radiology, which publishes articles related to imaging of the musculoskeletal system. It contributes to the journal's content by highlighting a rare presentation of lymphoma affecting skeletal muscle and discussing the diagnostic challenges involved, which would be valuable for radiologists and orthopedic surgeons.