Primary Cutaneous CD8+ Aggressive Epidermotropic Cytotoxic T-Cell Lymphoma: A Rare and Aggressive Case Report with Clinical and Pathological Insights

<b>Introduction:</b> Primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (PCAETL) is a rare and highly aggressive subtype of cutaneous T-cell lymphoma (CTCL), accounting for less than 1% of CTCL cases. It is defined by CD8+ cytotoxic T-cell proliferation with marked epidermotropism, necrosis, and a high proliferative index. Clinically, it presents as ulcerated or necrotic lesions with rapid progression and poor response to conventional therapies. <b>Aims:</b> To describe a fatal case of PCAETL in a young adult female, emphasizing the diagnostic challenges, clinical progression, histopathological features, and treatment limitations. <b>Case Presentation:</b> A 41-year-old Venezuelan woman presented with a 10-month history of disseminated papules and nodules initially misdiagnosed as Hansen's disease. After her arrival in Ecuador, she was re-evaluated and found to have generalized dermatosis with ulcerated nodules and tumors. Histopathological examination revealed atypical epidermotropic CD8+ T-cell infiltration with extensive necrosis. Immunohistochemistry demonstrated strong positivity for CD3, CD5, and CD8, and a Ki-67 index of 80%, confirming the diagnosis of PCAETL. The patient received methotrexate with partial response but experienced disease relapse during second-line etoposide therapy. She developed febrile neutropenia and died five months after diagnosis. <b>Conclusions:</b> This case highlights the rarity, diagnostic complexity, and aggressive nature of PCAETL. Early recognition and clinico-pathological correlation are essential for timely diagnosis. However, therapeutic options remain limited, and outcomes are poor despite systemic chemotherapy. Further research into targeted and personalized therapies is urgently needed to improve survival in this devastating disease.