Abstract
Background: Kaposi sarcoma (KS) is a human herpesvirus 8 (HHV-8)–associated angioproliferative malignancy with distinct epidemiological and clinical variants. While HIV-associated KS has been extensively studied, data on HIV-negative KS remain limited, particularly in North Africa. Morocco represents a unique geographic setting at the intersection of Mediterranean and sub-Saharan epidemiological influences, yet contemporary cohort data are scarce. Objective: To describe the clinical, epidemiological, therapeutic, and survival characteristics of HIV-negative Kaposi sarcoma in a Moroccan tertiary referral center over a 13-year period. Methods: We conducted a retrospective study of HIV-negative patients with histologically confirmed KS managed at Ibn Rochd University Hospital (Casablanca, Morocco) between January 2012 and January 2025. Clinical, demographic, pathological, and treatment data were extracted from medical records. Overall survival was estimated using the Kaplan–Meier method. Analyses were descriptive and exploratory. Results: A total of 26 HIV-negative patients were included. The cohort comprised 62% males, with a mean age at diagnosis of 62.5 years (SD = 23.3). The classic variant predominated (77%), followed by iatrogenic (15%) and endemic (8%) forms. Nearly half of patients (46%) presented with advanced stage IV disease. Lesions were predominantly peripheral, involving both upper and lower limbs in 65.4% of cases, with frequent mucosal (23.1%) and visceral (11.5%) involvement. Comorbidities were present in 61.5% of patients, mainly cardiovascular and metabolic disorders. Paclitaxel and bleomycin were the most commonly used treatments, with heterogeneous outcomes reflecting disease severity and treatment selection bias. Secondary malignancies and/or suspected visceral involvement occurred in 26.9% of patients, predominantly pulmonary lesions (57.1% of this subgroup). Kaplan–Meier analysis revealed a biphasic survival pattern, suggesting coexistence of aggressive and indolent clinical trajectories. Conclusion: HIV-negative Kaposi sarcoma in Morocco is characterized by elderly onset, frequent advanced-stage presentation, and significant clinical heterogeneity. The observed biphasic survival pattern and notable rate of secondary malignancies or suspected visceral involvement of Kaposi sarcoma underscore the complexity of disease behavior in this population. These findings highlight the need for earlier diagnosis, improved risk stratification, and further studies exploring host susceptibility factors, including potential genetic and immunological determinants.