Classic Kaposi sarcoma in a patient of Miao ethnicity followed up for 7 years: a case report

Background Classic Kaposi sarcoma (CKS) is a vascular sarcoma associated with human herpesvirus 8 (HHV-8), which is known to be more common in Mediterranean elderly men and is characterized by indolent clinical behavior. Xinjiang province in China is considered an endemic region for Kaposi's sarcoma-associated herpesvirus (KSHV), with higher incidence among adults of Kazak and Uyghur ethnicities. Cases of CKS are rarely reported in inland China. Here, we followed a case of CKS for 7 years in a patient of Miao ethnic background in southwestern China. Case presentation A 63-year-old Miao (southwestern China) man was initially diagnosed with CKS in 2010, having a history of limb lesions for 37 years, with left eyelid and binaural lesions for 9 years. He did not have sexual contact with men and was human immunodeficiency virus (HIV)-negative. Due to his lumbago and fever, spinal tuberculosis in the lumbar vertebra was highly suspected after computed tomography (CT) scan. However, diagnostic antituberculosis treatment for 4 weeks failed. The patient was followed up in 2016, when the rash was recovering as the systemic symptoms improved. A new CT was performed, which showed a partial response despite the absence of any medical treatment. The open reading frame (ORF)-K1 of KSHV from skin tissue of the foot was amplified and sequenced, and K1 belonged to subtype A. This genotype is consistent with the typical subtype present in Xinjiang. Conclusions We describe spontaneous partial regression of CKS in a patient of Miao ethnicity in inland China. Our sample may represent an unknown, novel genotype. Surveillance and regulating the immune state may represent a valuable approach for this rare disease.