Reversible rituximab-induced rectal Kaposi’s sarcoma misdiagnosed as ulcerative colitis in a patient with HIV-negative follicular lymphoma

Abstract

BackgroundKaposi’s sarcoma is a low-grade mesenchymal angioproliferative tumor, most commonly observed in immunocompromised individuals, such as HIV-infected patients. Iatrogenic Kaposi’s sarcoma occurs in patients undergoing immunosuppressive therapies. Rituximab is a chimeric monoclonal antibody targeted against the pan B cell marker CD20. Because of its immunosuppressive effects through reduction of mature B-cells, it may exacerbate Kaposi’s sarcoma in HIV-positive patients. Rituximab-related Kaposi’s sarcomas have been previously reported in only two HIV-negative patients and were treated surgically.Case presentationHere, we report on a Kaposi’s sarcoma that developed under rituximab treatment in a HIV-negative 55-year-old patient treated for follicular lymphoma. The lesion developed during the maintenance rituximab therapy at the rectal level with an aspect of apparent ulcerative colitis, without any cutaneous lesion. The premature stop of rituximab led to the complete regression of Kaposi’s sarcoma, without any additional specific treatment.ConclusionsTo our knowledge, this is the third case of Kaposi’s sarcoma diagnosed under rituximab in a HIV-negative patient, the first one at the rectal level and the first one that completely regresses after stop of rituximab. This case raises awareness of iatrogenic Kaposi’s sarcoma in HIV-negative patients treated with rituximab, and further highlights the importance of immunosuppression in the pathophysiology of disease.

Iatrogenic Kaposi’s sarcoma from induction therapy for myeloma: to transplant or not to transplant?

“…The AIDS Clinical Trials Group staging system takes into consideration the immune status with a CD4 cut-off of less than 200/µL as poor risk for HIV associated Kaposi’s 11. Several cases of iatrogenic Kaposi’s with CD4 counts beyond 350/µL are reported 12. Bortezomib is known to reduce the CD4+T cell count and lessens CD8 T-cell toxicity 13.…”

Disseminated form of the Kaposi sarcoma in HIV-negative patient associated with Hodgkin’s lymphoma

“…Based on the cases described in the literature, it is possible to conclude that KS development is typically associated with a patient’s immunosuppression of different origins, such as HIV and/or herpes virus infections, post-transplantation therapy and anticancer chemotherapy [ 1 , 2 ]. However, cases of KS in HIV-negative patients without deterioration of the immune status also have been reported [ 3–5 ].…”

Rituximab-Induced Kaposi Sarcoma in HIV-Negative Patients: A Narrative Review

“…A case study by Billon et al reports on a KS case that developed under rituximab treatment for follicular lymphoma in an HIV-negative, 55-year-old patient [ 29 ]. The lesion developed at the level of the rectum, approximately one year after rituximab initiation, more precisely during maintenance treatment.…”