Arjona-Sánchez Álvaro, Martínez-López Ana, Valenzuela-Molina Francisca, Rufián-Andújar Blanca, Rufián-Peña Sebastián, Casado-Adam Ángela, Sánchez-Hidalgo Juan Manuel, Rodríguez-Ortiz Lidia, Medina-Fernández Francisco Javier, Díaz-López Cesar, Granados-Rodríguez Melissa, Ortega-Salas Rosa, Castaño Justo P, Tena-Sempere Manuel, Briceño-Delgado Javier, Romero-Ruíz Antonio
Unit of Surgical Oncology, Department of Surgery, Reina Sofia University Hospital, Córdoba, Spain.
GE09 Research in Peritoneal and Retroperitoneal Oncological Surgery, Maimonides Biomedical Research Institute of Cordoba (IMIBIC), Reina Sofia University Hospital, University of Cordoba, ReinaCórdoba, Spain.
Ann Surg Oncol. 2022 Jan;29(1):126-136. doi: 10.1245/s10434-021-10372-9. Epub 2021 Jul 2.
Pseudomyxoma peritonei (PMP) is a rare malignancy, classified according to the Peritoneal Surface Oncology Group International (PSOGI) classification, whose response to treatment remains highly heterogeneous within the high-grade (HG) category. Molecular profiling of PMP cases might help to better categorize patients and predict treatment responses.
We studied the Ki-67 proliferation rate and P53 overexpression in tissue samples from our historical cohort of HG-PMP patients. We established as cut-off levels the third quartile of each marker to perform univariate and multivariate Cox regression survival analyses. According to these results, the HG-PMP category was divided into subcategories and a new survival analysis was performed.
A total of 90/117 patients with PMP undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) were selected for secondary analysis. The survival analysis of the HG-PMP category for preoperative variables showed that a proliferation index defined by Ki-67 >15% is a bad prognostic factor, with a hazard ratio (HR) of 3.20 (95% confidence interval [CI] 1.24-8.25). Accordingly, the HG-PMP group was divided using the Ki-67 15% cut-off. The new PSOGI/Ki-67 variable was an independent prognostic factor for overall survival (OS), with an HR of 3.74 (95% CI 1.88-7.47), and disease-free survival (DFS), with an HR of 4.184 (95% CI 1.79-9.75). The estimated 5-year OS rate was 100%, 70% and 24% for the LG-PMP, HG-PMP ≤15% and HG-PMP >15% groups, respectively (p = 0.0001), while the 5-year DFS rate was 90%, 44% and 0%, respectively (p = 0.0001).
Division of the HG-PMP category of the PSOGI classification, according to the Ki-67 proliferation index, provides two well-defined subcategories, with significant differences in terms of OS and DFS, and hence high prognostic value.
腹膜假黏液瘤（PMP）是一种罕见的恶性肿瘤，根据国际腹膜表面肿瘤学组（PSOGI）分类，其在高级别（HG）类别中对治疗的反应仍然高度异质性。PMP病例的分子谱分析可能有助于更好地对患者进行分类并预测治疗反应。
我们研究了HG-PMP患者历史队列组织样本中的Ki-67增殖率和P53过表达情况。我们将每个标志物的第三个四分位数确定为截断水平，以进行单变量和多变量Cox回归生存分析。根据这些结果，将HG-PMP类别分为亚类并进行了新的生存分析。
总共选择了117例接受减瘤手术（CRS）和热灌注化疗（HIPEC）的PMP患者中的90例进行二次分析。HG-PMP类别术前变量的生存分析表明，由Ki-67>15%定义的增殖指数是一个不良预后因素，风险比（HR）为3.20（95%置信区间[CI]1.24-8.25）。因此，使用Ki-67 15%的截断值对HG-PMP组进行划分。新的PSOGI/Ki-67变量是总生存期（OS）的独立预后因素，HR为3.74（95%CI 1.88-7.47），也是无病生存期（DFS）的独立预后因素，HR为4.184（95%CI 1.79-9.75）。LG-PMP、HG-PMP≤15%和HG-PMP>15%组的估计5年OS率分别为100%、70%和24%（p = 0.0001），而5年DFS率分别为90%、44%和0%（p = 0.0001）。
根据Ki-67增殖指数对PSOGI分类中的HG-PMP类别进行划分，可提供两个明确的亚类，在OS和DFS方面存在显著差异，因此具有较高的预后价值。
