The fifth subtype of Kaposi's sarcoma in HIV-negative, sexually active male patients. A retrospective cohort study at a New York City cancer center, 2000–2022

Abstract

In addition to the four known variants of Kaposi's sarcoma (classical, endemic, iatrogenic, and epidemic), there is a fifth subtype that has recently gained greater recognition. It is called non-epidemic Kaposi's sarcoma and occurs in men-sex-men (MSM) patients. It is postulated that this group is more likely to engage in high-risk sexual practices, facilitating the transmission of HHV-8.

This study included 72 HIV-negative MSM patients, and additional data were collected, including country of origin, use of immunosuppression, comorbidities, treatments received, and overall survival.

In addition to the four known variants of Kaposi's sarcoma (classical, endemic, iatrogenic, and epidemic), there is a fifth subtype that has recently gained greater recognition. It is called non-epidemic Kaposi's sarcoma and occurs in men-sex-men (MSM) patients. It is postulated that this group is more likely to engage in high-risk sexual practices, facilitating the transmission of HHV-8.

It was also suggested that strict subtyping was imperfect. As an example, they presented a 70-year-old male patient of Mediterranean descent with rheumatoid arthritis treated with immunosuppressants (MSM), who overlapped with criteria for classic, iatrogenic, and fifth variant Kaposi's sarcoma. The authors ultimately recognized the fifth variant as such when the main risk factor was being MSM, which increases the likelihood of contracting HHV-8. They emphasized that the age at presentation was younger than in the classic variant.