Background/Objectives: Kaposi sarcoma (KS) is a common lymphatic endothelial cancer among children with and without HIV in central and eastern Africa. Despite its clinical heterogeneity, its various clinical phenotypes are often grouped together in staging and treatment algorithms. Patients with KS tumor-associated edema, referring to hard, non-pitting lesions which often lead to chronic disability, represent a unique, understudied subgroup of children with KS. To continue our work defining the distinct phenotypes of pediatric KS, this study aimed to assess the clinical progression and outcomes of KS edema in children. Methods: A retrospective cohort study was conducted at Kamuzu Central Hospital in Lilongwe, Malawi, focusing on children diagnosed with KS edema between 2010 and 2023. Results: We identified 52 children with KS edema, representing 27% of all patients with KS. Initial chemotherapy resulted in a clinical response in 92% of patients, but 46% experienced relapse or disease progression with a median time to first relapse of 12 months. Multiple progressions were common, with 31% of patients experiencing two or more events. Event-free survival at two years was 32%, dropping to 24% at five years, while overall survival was 73% at two years and 57% at five years. Relapse was more common among patients with KS edema versus those without it (relative risk = 2.1; 95%CI, 1.4–3.2;p< 0.001). Eight patients (15%) relapsed with visceral disease, five of whom originally presented with KS edema alone. Conclusions: Patients with KS edema have a unique, relapsing-remitting pattern of disease with a high risk of relapse relative to other forms of KS with subsequent long-term mortality, even after initial positive treatment responses. Late relapse and mortality with visceral disease are possible even among children presenting initially with KS edema alone. Children with KS edema require long-term follow-up, and novel treatment approaches tailored towards preventing frequent relapse are needed.
背景/目的：卡波西肉瘤（KS）是中非和东非地区儿童（无论是否感染HIV）中常见的淋巴管内皮癌。尽管其临床异质性显著，但在分期和治疗方案中，其不同的临床表型常被归为一类。KS肿瘤相关性水肿患者（指坚硬、非凹陷性病变，常导致慢性功能障碍）构成了一个独特且研究不足的儿童KS亚群。为继续推进我们对儿童KS不同表型的研究，本研究旨在评估儿童KS水肿的临床进展和预后。方法：在马拉维利隆圭的卡姆祖中心医院开展了一项回顾性队列研究，重点关注2010年至2023年间诊断为KS水肿的儿童。结果：我们共识别出52例KS水肿患儿，占所有KS患者的27%。初始化疗后，92%的患者出现临床缓解，但46%的患者出现复发或疾病进展，中位首次复发时间为12个月。多次进展较为常见，31%的患者经历了两次或以上事件。两年无事件生存率为32%，五年降至24%；而两年总生存率为73%，五年为57%。与无水肿的KS患者相比，KS水肿患者的复发更为常见（相对风险=2.1；95%CI 1.4–3.2；p<0.001）。8例患者（15%）出现内脏疾病复发，其中5例最初仅表现为KS水肿。结论：KS水肿患者具有独特的复发-缓解疾病模式，与其他形式的KS相比复发风险更高，且即使在初始治疗反应良好后，仍存在长期死亡风险。即使最初仅表现为KS水肿的儿童，也可能出现晚期复发和内脏疾病导致的死亡。KS水肿患儿需要长期随访，并需开发针对预防频繁复发的新型治疗方法。
肿瘤(癌症)患者之家