A Case of Kaposi’s Sarcoma in a HIV Negative Patient with CLL Treated with Rituximab

Case Description: - A 76 year old lady was diagnosed with Chronic Lymphocytic Leukemia (CLL) with 11 q deletion after she presented with generalized lymphadenopathy and anemia. She was treated with rituximab 375mg/m2 day1 and bendamustine 60mg/m2 on day 1 and day 2 and completed six cycles of treatment. After the sixth cycle she developed multiple itchy, papular lesions with bleeding on both lower extremities. She was evaluated multiple times by vascular surgery and dermatology without a definitive diagnosis. She underwent a biopsy with staining for HHV-8, CD31 and CD34 which was positive confirming the diagnosis of Kaposi sarcoma. ELISA test for HIV was negative. She was started on treatment with Doxorubicin 20 mg/m2every 3 weeks and with 3 cycles there was significant regression of the lesions. Discussion-: We describe a case of CLL which was initially started on treatment with rituximab and bendamustine. She tolerated the treatment well, but a few months later presented with skin lesions which on biopsy was diagnosed as Kaposi sarcoma. It is very uncommon for Kaposi sarcoma to develop in a HIV negative patient. This patient was immunocompromised with recent chemotherapy. Rituximab specifically depletes B cells and leads to impaired T cell mediated immunity. This case illustrates the importance of a high index of suspicion in patients treated with rituximab as it is used for a number of hematologic malignancies like leukemia, lymphoma as well as non-malignant conditions like autoimmune disorders. While infusion reactions and reactivation of hepatitis B are side effects physicians are aware of and cautious of while using rituximab, Kaposi’s Sarcoma remains a less known side effect. Awareness of this possibility is important in physicians prescribing rituximab. Footnotes * Asterisk with author names denotes non-ASH members. Disclosures No relevant conflicts of interest to declare.