Rare cutaneous manifestation of B-cell chronic lymphocytic leukaemia involving the toes

B cell chronic lymphocytic leukaemia (B-CLL) presenting with cutaneous infiltration is rare, and when it occurs, it presents most commonly on the head and neck. We present the case of an 80-year-old woman with a 2-month history of erythema, swelling and pain affecting all her toes. She had a history of B-CLL diagnosed 20 years previously that had remained stable under observation without treatment. A toe skin biopsy showed a diffuse infiltrate of lymphoid cells occupying the dermis composed of small mature lymphoid cells with a monotonous appearance. On immunohistochemistry, the neoplastic lymphoid cells stained positive for the B-cell marker CD20. Overall, the morphology and immunophenotype were consistent with cutaneous involvement by chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL). We concluded that her symptoms were directly caused by skin infiltration of B-CLL. An 80-year-old woman with a history of untreated, stable B-cell chronic lymphocytic leukaemia (B-CLL) presented with erythema, swelling, and pain in all toes, lasting two months. A skin biopsy from her toe showed a dermal infiltrate of monotonous, small, mature lymphoid cells. These cells tested positive for the B-cell marker CD20, confirming cutaneous involvement by CLL. Her toe symptoms were attributed to B-CLL skin infiltration. image