A rare case report: cytarabine-induced skin rash

Diffuse Large B-Cell Lymphoma (DLBCL) is the most common subtype of Non-Hodgkin Lymphoma (NHL). The standard first-line treatment for DLBCL is the R-CHOP protocol. For relapsed or refractory cases, salvage regimens such as R-ICE, R-DHAP, or MATRIX are utilized. Cytarabine, a commonly used antimetabolite in hematologic malignancies, has various side effects, including dermatological toxicity. A 61-year-old male with DLBCL received six cycles of R-CHOP chemotherapy and was considered in remission. However, he presented with neurological symptoms, and imaging confirmed CNS relapse. The patient was started on the MATRIX regimen, including high-dose cytarabine. On the third day of treatment, he developed a palmar rash, which later progressed to petechiae and purpura on the trunk, back, and lower extremities. No systemic corticosteroid treatment was administered, and the rash gradually resolved by the 13th day. Cytarabine-induced skin reactions, such as palmar-plantar erythrodysesthesia, morbilliform rashes, and acute generalized exanthematous pustulosis, have been reported. However, cases involving petechiae and purpura are rare. These reactions are usually self-limiting and do not require systemic intervention. The severity of cytarabine-induced dermatologic toxicity may be dose-dependent, with repeated doses showing reduced severity. In this case, the patient exhibited a cutaneous reaction without systemic involvement, supporting the benign nature of cytarabine-related skin toxicity. This case highlights a rare dermatological reaction to cytarabine during the MATRIX regimen in a DLBCL patient with CNS relapse. Although cytarabine-induced skin toxicity is uncommon, clinicians should be aware of its potential manifestations and manage patients symptomatically to avoid unnecessary interventions while ensuring treatment continuation.