组织学器官受累（HOI）程度可能对腹膜后脂肪肉瘤患者的预后产生影响。本研究调查了这些患者中HOI的发生率、特点和风险因素。回顾性分析了2009-2014年接受多器官切除术治疗原发性脂肪肉瘤的患者的数据。HOI是感兴趣的变量，并分为四个程度：未发现（HOI-0）、周围器官（HOI-1）、初级受累（HOI-2）和高级受累（HOI-3）。主要终点是总生存期（OS），次要终点是无病生存期（DFS）。校正了术前治疗和Sarculator预测得分的HOI的预后价值。共纳入109名患者。其中9例患者（8.3%）、11例患者（10.1%）、43例患者（39.4%）和46例患者（42.2%）出现了HOI-0、HOI-1、HOI-2和HOI-3。中位随访时间为8.4年【四分位距（IQR）7.2-9.6年】。共观察到68例复发和50例患者死亡，导致10年OS和DFS分别为51.1%（95%置信区间（CI）41.9-62.1%）和34.1%（95% CI 25.2-46.1%）。良、恶性不分化的脂肪肉瘤中分别发现了35/45（77.8%）和54/64（84.4%）例临床相关的HOI-2和HOI-3。在多变量生存分析中，与HOI-0/HOI-1相比，HOI-3患者的OS（HR 2.92；p = 0.012）和DFS（HR 2.23；p = 0.045）显著较短，与预测得分（OS：HR 2.93；p < 0.001；DFS：HR 1.78；p = 0.003）无关。初级和高级的HOI在良、恶性不分化的脂肪肉瘤中经常出现，支持可能需要多器官切除术。HOI可分层患原发性腹膜后脂肪肉瘤的风险。©2023年，外科肿瘤学会。

The extent of histological organ involvement (HOI) to organs and structures of a retroperitoneal liposarcoma may have prognostic implications. This study investigated incidence, characteristics, and risk association of HOI in these patients.Data of patients who underwent multivisceral resection for primary liposarcoma (2009-2014) were retrospectively analyzed. HOI was the variable of interest and was classified into four degrees: absent (HOI-0), perivisceral (HOI-1), initial (HOI-2), and advanced (HOI-3). Primary endpoint was overall survival (OS). Secondary endpoint was disease-free survival (DFS). The prognostic value of HOI was adjusted for preoperative treatment and the Sarculator nomogram score.A total of 109 patients were included. HOI-0, HOI-1, HOI-2, and HOI-3 were detected in 9 (8.3%), 11 (10.1%), 43 (39.4%), and 46 (42.2%) patients. Median follow-up was 8.4 years [interquartile range (IQR) 7.2-9.6 years]. There were 68 recurrences and 50 patient deaths observed, resulting in a 10-year OS and DFS of 51.1% [95% confidence interval (CI) 41.9-62.1%] and 34.1% (95% CI 25.2-46.1%), respectively. Clinically relevant HOIs (HOI-2 and HOI-3) were found in 35/45 (77.8%) and 54/64 (84.4%) cases of well- and de-differentiated liposarcomas, respectively. On multivariable survival analysis, patients with HOI-3 had significantly shorter OS (HOI-3 vs HOI-0/HOI-1 HR 2.92; p = 0.012) and DFS (HOI-3 vs HOI-0/HOI-1 HR 2.23; p = 0.045), independently of the nomogram score (OS: HR 2.93; p < 0.001; DFS: HR 1.78; p = 0.003).Initial and advanced HOIs are frequently detected in both well-differentiated and de-differentiated liposarcomas, supporting that multivisceral resection may be needed. HOI stratifies the risk of patients with primary retroperitoneal liposarcoma.© 2023. Society of Surgical Oncology.