A case report of iatrogenic cutaneous Kaposi sarcoma due to rituximab therapy for thrombotic thrombocytopenic purpura

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

Kaposi sarcoma (KS) is a low-grade mesenchymal angioproliferative disorder that requires infection with human herpes virus 8 (HHV-8) for it to develop. It is commonly seen in HIV-positive patients and rarely in immunosuppressed HIV-negative patients. Rituximab is a monoclonal anti-CD20 chimeric murine/human immunoglobulin G antibody used to treat B cell lymphoproliferative diseases as well as a variety of autoimmune disorders. Several cases of iatrogenic Kaposi sarcoma (iKS) have been described after rituximab treatment. The purpose of this narrative review is to identify the presence of common clinical characteristics among rituximab-induced KS patients that could facilitate better management of this rare condition.

Kaposi's sarcoma in a patient with pemphigus vulgaris mimicking exacerbation of pemphigus

BACKGROUND

Kaposi's sarcoma (KS) is a rare multifocal angiogenic tumor often seen in immunocompromised setting such as acquired immunodeficiency syndrome (AIDS) or organ transplantation recipients. Pemphigus vulgaris (PV) is a rare blistering disorder with mucocutaneous involvement for which immunosuppressive therapy has long been the core of treatment. Iatrogenic form of KS has been reported infrequently in pemphigus patients as a result of long-term immunosuppressive therapy.

CASE

We describe a 39-year-old male patient with confirmed diagnosis of PV who developed KS after receiving immunosuppressive agents for his pemphigus. KS was initially localized to the oral cavity with features mimicking exacerbation of his pemphigus.

CONCLUSION

This interesting case of KS suggests that dermatologists visiting patients with pemphigus with discomfort in the oral cavity should have a high degree of awareness and consider other differential diagnoses along with merely an exacerbation of PV.

Kaposi's sarcoma, biologics and small molecules: Navigating the complex interplay between host immunity and viral biology. A case series with focused review of the literature

The consequences of cytokine-specific immune modulation in the development and course of Kaposi's sarcoma (KS) are poorly understood. A retrospective chart review of patients treated with biologic/small molecule drugs and followed at the dedicated KS outpatient service of our Dermatology Unit was performed. The literature on biologic and small molecule drug use in KS patients was also reviewed. Data concerning 12 KS patients treated with biologic/small molecule drugs were collected. After a median delay of 6 months following biologic or small molecule drug introduction, nine patients experienced either KS onset or reactivation. Drugs associated with KS onset or flaring were: rituximab, infliximab, ruxolitinib apremilast (1), mirikizumab, abatacept (1). After a median follow-up of 25 months, all cases achieved persistent complete response through culprit drug discontinuation or drug withdrawal plus treatment. No effect on KS course was recorded with tocilizumab and vedolizumab. Based on our experience with the largest case series reported to date as well as the available literature, tocilizumab and ustekinumab seem to exert an overall neutral effect on KS. On the other hand, rituximab, infliximab, and ruxolitinib have been associated with the development or worsening of pre-existing KS and should be carefully pondered before use. Due to limited and partly controversial evidence, no definitive conclusions can be drawn on vedolizumab, apremilast, mirikizumab, abatacept.

Refractory Thrombotic Thrombocytopenic Purpura in a patient with Kaposi sarcoma

The case is here presented of a 70-year old male patient with rare coexistence of Kaposi Sarcoma and resistant Thrombotic Thrombocytopenic Purpura (TTP). The Kaposi lesions were determined before the diagnosis of TTP and were exacerbated after receiving TTP-associated immunosuppressive therapy, in particular associated with rituximab. TTP in this case was resistant to conventional therapies such as steroid and plasma exchange and current immunosuppressive (rituximab, cyclophosphamide, vincristin) treatments. Novel treatment agents consisting of bortezomib and eculizumab given to the patient were also ineffective. To the best of our knowledge, this case presents the first case of coexistence of TTP and Kaposi sarcoma from Turkey and the challenge of refractory TTP management.

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

Background

Kaposi’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 presentation

Here, 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.

Conclusions

To 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: a Retrospective Cohort Study in an Italian Tertiary Care Centre

AIMS

Kaposi's sarcoma (KS) is a lymphoangioproliferative multicentric disorder. Among its four distinct clinical variants, iatrogenic KS (iKS) typically affects patients who have received immunosuppressant regimens for organ transplants, proliferative disorders, or immune-mediated diseases. The aim of the current study was to examine the characteristics of a cohort of patients with iKS, evaluating the differences in terms of epidemiological and clinical features, management and outcomes between organ transplant recipients (OTR) and patients immunosuppressed for other medical conditions.

MATERIALS AND METHODS

This retrospective study included, out of 1389 KS patients, 143 patients suffering from iKS being followed in an Italian tertiary care centre from November 1995 to December 2016. Demographic data, clinical features, previous immunosuppressive therapies, management, and outcomes were recorded for each patient.

RESULTS

We detected iKS in 10.3% of the analysed KS population. The mean age was 71.9 years in non-OTR versus 51.4 years in OTR (P = 0.04). Staging at diagnosis showed a more severe disease in non-OTR than in OTR, with stage IA observed in 33.3% of OTR versus 11.8% of non-OTR (P < 0.001) and stage IVB in 29.1% of non-OTR versus 12.1% of OTR (P = 0.001). Corticosteroids represented the most frequent immunosuppressive drugs at diagnosis in both groups, in conjunction with cyclosporine A in OTR. Immunosuppressant reduction or withdrawal was carried out in 93.9% of OTR versus 63.6% of non-OTR (P < 0.001).

CONCLUSIONS

As corticosteroids and cyclosporine A are the most common iKS-inducing drugs, their reduction or withdrawal, wherever possible, is needed. Differences in disease severity at presentation between OTR and non-OTR may interfere with the choice of management strategy and the consequent outcome.