Clinicopathological characteristics and treatment outcomes of cutaneous extranodal natural killer/T-cell lymphoma: a retrospective study in China

Background: Extranodal natural killer/T--cell lymphoma (ENKTL) is a special subtype of non-Hodgkin lymphoma that is subcategorized into ENKTL-nasal and ENKTL-nasal type. Cases with extranasal involvement show an aggressive clinical course with poor prognosis and low survival rates. The skin is the second most commonly affected organ, and such cases are defined as cutaneous ENKTL. However, there is limited information on the clinicopathologic features and prognostic factors of cutaneous ENKTL. Methods: We reviewed the pathologic, immunohistochemical, and clinical data for 47 cases of cutaneous ENKTL. Results: Cutaneous ENKTL mainly involved the torso and extremities, with lesions presenting as single or multiple nodules, erythema and rash, or painless necrotic ulcers. There was high surface CD3 expression. The median survival time was 4.0 months (95% CI: 2.3-5.7 months). Stage I/II patients had a better outcome, with a mean survival time of >26 months (95% CI: 17.68-35.92 months). Stage 111/W patients had very poor outcome, with overall survival of 4.7 months (95% Cl: 1.01-2.73 months). The presence of B symptoms, advanced tumor stage, increased lactate dehydrogenase level, high International Prognostic Index (IPI), and abnormal hemoglobin were independent prognostic factors for poor survival. Patients were more responsive to treatment with an L-asparaginase-based chemotherapy regimen than to other therapeutic approaches. Conclusions: Cutaneous and primary nasal ENKTL differ in terms of clinical and biological characteristics. Cutaneous ENKTL has a short median survival time. Although an L-asparaginase-containing chemotherapy regimen was effective, a standardized treatment strategy remains to be established for cutaneous ENKTL.