Systemic progression of primary cutaneous anaplastic large cell lymphoma in ¹⁸F-FDG PET/CT: a case report

Primary cutaneous anaplastic large cell lymphoma (pcALCL) is a type of skin T-cell lymphoma with a favorable prognosis. Some patients may experience recurrence, but systemic involvement is rare. Some studies suggest that systemic progression is associated with poor prognosis. The value of ¹⁸F-FDG PET/CT in diagnosing lymphoma has been recognized, but there is often controversy over the application value of ¹⁸F-FDG PET/CT in pcALCL. We present a rare case of pcALCL involving multiple systemic lesions, monitored and evaluated using ¹⁸F-FDG PET/CT to assist in clinical treatment decisions. Through this case, we consider that ¹⁸F-FDG PET/CT has significant value in diagnosing pcALCL. However, more clinical cases are needed to confirm whether high FDG uptake is associated with the invasiveness of pcALCL and the impact of high FDG uptake and Ki-67 expression on the progression and prognosis of pcALCL.