Diagnosis and prognostic analysis of skin infiltration in chronic lymphocytic leukemia: a case report and literature review.

Background: Chronic lymphocytic leukemia (CLL) is a malignant lymphoproliferative disorder; excessive aggregation of small mature B cells in peripheral blood, bone marrow, lymph nodes, and spleen is characteristic. Cutaneous involvement of CLL can be classified into specific skin lesions, including skin infiltration by leukemic cells, secondary cutis tumors, nonspecific lesions and associated skin diseases. Uncommonly, skin infiltration in patients who are diagnosed with CLL can be localized or widespread, and it can take various forms, including nodules, plaques, papules, and ulcers. Case Description: We report a 52-year-old patient diagnosed for CLL with skin infiltration, whose lesions were subcutaneous nodules, widely distributed in the nasal base, right auricle, extremities, and trunk. Lesions are firm, without tenderness and have poor mobility. Spontaneous regression of some skin lesions is the most prominent feature. The pathological biopsy of skin tissue showed that small round cells infiltrated subcutaneous adipose tissue. The immunohistochemical results were consistent with the immunophenotype of neoplastic B cells, and the aberrant co-expression of CD5 and CD23 was the significant marker. The patient is currently being followed up. Conclusions: Aggressive treatment of the primary disease can alleviate the skin symptoms to a certain extent, and the prognosis of patients is affected by multiple factors such as the extent of the lesions, whether accompanied by epidermal changes, the site of infiltration and the percentage of small B lymphocytes. Long-term follow-up is necessary.