Combined ultrasonography and CT for prognosis and predicting clinical outcomes of patients with pseudomyxoma peritonei.

OBJECTIVES: This study aimed to identify the diagnostic accuracy of combined ultrasonography (US) and computed tomography (CT) in evaluating the tumor burden of pseudomyxoma peritonei (PMP). Besides, we assessed the ability of this combination to predict the likelihood of complete resection. METHODS: This retrospective study involved 504 patients diagnosed with PMP and scheduled for cytoreduction surgery. We compared tumor burden-quantified as peritoneal cancer index (PCI) by preoperative US and CT (US-CT-PCI)-with surgical findings. Next, we assessed the prognostic value of US-CT PCI and imaging features in determining the completeness of cytoreduction (CCR) score using multivariate analysis. RESULTS: US-CT PCI demonstrated a high PCI evaluation accuracy under moderate tumor burden. Higher US-CT PCI could predict incomplete resection. In addition, we identified imaging features such as mesenteric involvement as an independent predictor of incomplete resection (hazard ratio (HR) = 2.006; p = 0.007). CONCLUSIONS: US-CT PCI allowed us to predict the completeness of cytoreductive surgery in patients with PMP. Moreover, the combined US and CT imaging detected several features indicating incomplete cytoreduction. KEY POINTS: • Ultrasonography (US) can act as a complementary diagnostic modality in peritoneal cancer index (PCI) evaluation by combining CT in the small bowel area and US in the abdominal area. • A modified peritoneal cancer index (US-CT PCI) helps preoperatively evaluate tumor burden with high accuracy and allows to predict incomplete resection. • US-CT PCI of 20 or above and the involvement of particular structures such as mesentery, independently indicate incomplete resection.

Significance of laparoscopic cytoreductive surgery for appendiceal pseudomyxoma peritonei with limited disease and low tumor burden.

OBJECTIVE: To investigate the clinical value of laparoscopic cytoreductive surgery (CRS) in treating of appendiceal pseudomyxoma peritonei with limited disease and low tumor burden. METHODS: The clinical data of patients with appendiceal pseudomyxoma peritonei treated by surgery with CRS at the Aerospace Center Hospital from January 2018 to December 2021 were retrospectively analyzed. The patients were divided into laparoscopic or open CRS groups according to the operation method. A propensity score-matched (PSM) analysis (1:1) was performed, the related clinical variables were compared between the two groups, and the effect on progression-free survival (PFS) was also analyzed. RESULTS: One hundred and eight patients were included in this study. After PSM, 33 patients were selected from each group and the age and peritoneal cancer index were matched between the two groups. There were significant differences in operation time (P < 0.001), intraoperative bleeding (P < 0.001), intraoperative blood transfusion (P = 0.007), hospital stay (P < 0.001). The analysis of PFS showed that there was no significant difference between the two operation methods. After multivariate analysis, the pathologic subtype (P = 0.012) was identified as an independent prognostic factor for PFS. CONCLUSION: The curative effect of laparoscopic CRS is like that of open operation, which can significantly shorten the operation time and hospital stay and reduce intraoperative bleeding and blood transfusion event. The laparoscopic CRS is safe and feasible in strictly selected patients. The pathologic subtype is an independent factor affecting the prognosis for PFS.

Preoperative systemic chemotherapy does not benefit for appendiceal pseudomyxoma peritonei.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a clinically malignant tumour syndrome mainly derived from mucin-producing appendiceal tumours. This study aimed to explore the effect of preoperative systemic chemotherapy (PSC) before cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) on the safety and postoperative survival in patients with appendiceal PMP. METHODS: We performed a retrospective analysis including consecutive patients with PMP undergoing primary surgery between January, 2008 and December, 2019 in Aerospace Center Hospital. The clinical data and postoperative survival were compared between PSC group and non-PSC group. RESULTS: Seven hundred and fifty patients were included in the study. Significant differences were found between PSC group and non-PSC group on clinicopathological data and perioperative outcomes and the independent risk factor of serious complications was blood loss >1000 mL (P = 0.026). Shorter median overall survival (OS) was found (42 months, 95% CI 31.9-52.1) in PSC group than that (67 months 95% CI 44.5-89.5) in non-PSC group. In the stratified study with PCI < 20, CC 0/1 and low-grade pathological subtype, the OS from non-PSC group was significantly better than that in PSC group (log rank P-values are <0.001, 0.006 and <0.001, respectively). Multivariate survival analysis showed that CC 0/1, HIPEC, PCI < 20 and low-grade pathological subtype were the independent prognostic factors for better OS. CONCLUSIONS: PSC does not increase the risk of major perioperative complications in patients with appendiceal PMP, but it also does not bring postoperative survival benefits to patients either.

Radiomics analysis based on CT's greater omental caking for predicting pathological grading of pseudomyxoma peritonei.

The objective of this study was to predict the preoperative pathological grading and survival period of Pseudomyxoma peritonei (PMP) by establishing models, including a radiomics model with greater omental caking as the imaging observation index, a clinical model including clinical indexes, and a combined model of these two. A total of 88 PMP patients were selected. Clinical data of patients, including age, sex, preoperative serum tumor markers [CEA, CA125, and CA199], survival time, and preoperative computed tomography (CT) images were analyzed. Three models (clinical model, radiomics model and combined model) were used to predict PMP pathological grading. The models' diagnostic efficiency was compared and analyzed by building the receiver operating characteristic (ROC) curve. Simultaneously, the impact of PMP's different pathological grades was evaluated. The results showed that the radiomics model based on the CT's greater omental caking, an area under the ROC curve ([AUC] = 0.878), and the combined model (AUC = 0.899) had diagnostic power for determining PMP pathological grading. The imaging radiomics model based on CT greater omental caking can be used to predict PMP pathological grading, which is important in the treatment selection method and prognosis assessment.

Case Report: Stage IIIc primary malignant mixed Müllerian tumor of the fallopian tube: A case of 5-year disease-free survival after cytoreductive surgery combined with peritoneal resection and adjuvant chemotherapy with paclitaxel plus carboplatin.

Malignant mixed Müllerian tumor (MMMT) of the fallopian tube is rare and has a poor prognosis. For the patient with fallopian tube MMMT, complete resection of the tumor invading the viscera and the peritoneum is a prerequisite for long-term survival. We report a case of stage IIIc MMMT of the fallopian tube treated by cytoreductive surgery (CRS), peritoneal resection, and adjuvant chemotherapy (paclitaxel plus carboplatin), with 5-year tumor-free survival. Postoperative chemotherapy combining platinum and paclitaxel is the most potent adjuvant therapy.

Prognostic Value of CEA, CA19-9, CA125, CA724, and CA242 in Serum and Ascites in Pseudomyxoma Peritonei.

PURPOSE: To investigate the expression of carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), CA19-9, CA724, and CA242 in serum and ascites of pseudomyxoma peritonei (PMP) patients and evaluate the predictive value of these elevated biomarkers in pathological grade, completeness of cytoreduction (CC), and survival. METHODS: From May 2009 to October 2019, a total of 512 patients diagnosed with PMP through pathology in Aerospace Center Hospital were enrolled. The serum and ascites tumor biomarkers were obtained. The diagnostic values between serum and ascites biomarkers in pathology and CC were compared by the receiver operating characteristic (ROC) curves. The correlation between pathology, cytoreduction, and biomarkers was calculated by univariate and multivariate logistic regression. The associations between different numbers of elevated biomarkers and survival status were examined using univariate and multivariate backward Cox proportional hazard regression models. RESULTS: The results showed that the areas under the ROC curves (AUROC) in the diagnosis of CC were 0.798 (95% CI: 0.760-0.836) and 0.632 (95% CI: 0.588-0.676) in serum and ascites biomarkers, respectively. The elevated serum and ascites biomarkers were independent risk factors for both pathology and CC. The 1-year, 3-year, and 5-year survival rates were 89.07%, 73.22%, and 66.94%, respectively. Longer survival was observed in patients who had less than two elevated serum biomarkers compared with those with 2-3 and 4-5 elevated serum biomarkers (p < 0.001). CONCLUSION: CEA, CA125, CA19-9, CA724, and CA242 in serum and ascites can be used to judge the severity and predict the resectability. Furthermore, different numbers of elevated biomarkers can help determine the prognosis of PMP.

Complete Cytoreductive Surgery vs. Debulking Surgery for pseudomyxoma peritonei of appendiceal origin: A propensity score-matched study based on a single-center experience.

OBJECTIVE: This study aimed to report the prognostic predictors and compare the long-term outcomes of complete cytoreductive surgery (CCRS) vs. debulking surgery (DS) in patients with pseudomyxoma peritonei (PMP) of appendiceal origin. METHODS: A retrospective analysis of 1008 consecutive patients with PMP undergoing primary surgery from January 2008 to December 2019 was performed. A propensity score-matched (PSM) analysis (1:1) was performed, and oncologic outcomes were compared between the CCRS and DS groups. RESULTS: Out of 1008 patients, 258 patients were excluded. Baseline characteristics differed significantly between the CCRS and DS groups (total n = 750). After PSM, 106 patients were selected from each group and the baseline characteristics were matched between groups. There were significant differences between groups in operative time, the incidence of major complications (P = 0.017), and the numbers of organs removed. The median follow-up was 28 (1-131) months. Median overall survival (OS) for the 212 patients was 52.0 months (95% CI 40.2-63.8), and 10-year OS was 39.0%. Median OS could not be calculated for the CCRS group; in the DS group, this value was 41 months (P = 0.010). The 10-year OS rate was 54.2% in the CCRS group and 31.2% in the DS group. Multivariate analyses identified CCRS (P = 0.012) and histopathologic subtype (P < 0.001) as independent prognostic factors for OS. CONCLUSIONS: In this matched-pair analysis of patients with appendiceal PMP, CCRS was safe and associated with better prognosis than DS. The completeness of cytoreduction and histopathologic subtype were two independent prognostic factors for OS.

The mutational landscape and prognostic indicators of pseudomyxoma peritonei originating from the ovary.

Pseudomyxoma peritonei (PMP) is a rare disorder with unique pathological and genetic changes. Although several studies have reported the clinical features and mutational changes of PMP that originates from the appendix, few studies on PMP originating from the ovary have been reported due to its extreme rarity. In order to characterize the somatic mutational landscape and to investigate the prognosis predicting factors of ovary-originating PMP, we examined 830 cases of PMP and identified 16 patients with PMP that originated from the ovary. Whole-exome sequencing (WES) was performed on 12 cases using formalin-fixed, paraffin-embedded (FFPE) tissue samples. We found that 25% (3/12) of the patients carried mutations in cancer driver genes, including TP53, ATM and SETD2, and 16.7% (2/12) of the patients carried mutations in cancer driver genes, including ATRX, EP300, FGFR2, KRAS, NOCR1 and RB1. The MUC16 (58.33%), BSN (41.67%), PCNT (41.67%), PPP2R5A (41.67%), PRSS36 (41.67%), PTPRK (41.67%) and SBF1 (41.67%) genes presented the highest mutational frequencies. The PI3K-Akt signaling pathway, human papillomavirus infection pathway, cell skeleton, cell adhesion, and extracellular matrix and membrane proteins were the major pathways or functions that were affected. Patients were followed up to 174 months (median: 48.26 months). The 5-year OS rate for all patients was 71.2% and the median OS was not reached. PTPRK mutations, presurgical CA199 level, completeness of cytoreduction (CCR) and peritoneal cancer index (PCI) were identified as potential predictive factors for patient survival. In conclusion, the mutational landscape for ovary-originating PMP was revealed and exhibited unique features distinct from appendix-originating PMP. PTPRK, CA199, CCR and PCI may predict patient survival.

Management and prognostic prediction of appendiceal mucinous adenocarcinoma with peritoneal metastasis: a single center study in China.

BACKGROUND: To investigate the clinical and pathological characteristics of appendiceal mucinous adenocarcinoma with peritoneal metastasis and analyze the prognostic factors. METHODS: A retrospective analyses of clinicopathological features of 50 patients with appendiceal mucinous adenocarcinoma with peritoneal metastasis from January, 2013 to December, 2017 in Aerospace Central Hospital, Beijing, China. Survival data calculation and comparison were respectively performed with the Kaplan-Meier method and the log-rank test. The Cox proportional hazards regression method was used for multivariate survival analyses. RESULTS: Cytoreduction for appendiceal mucinous adenocarcinoma was conducted on 50 patients (24 males and 26 females), with a median age of 52.5 years at the time of surgery (range 31-71 years). The median overall survival (OS) time was 24 months, with 2-,3- and 5-year survival rates of 53, 24 and 8%, respectively. At the last follow-up in December 2018, 13 patients were still alive. Multivariate analysis revealed that patients who had low Ki-67 expression (less than 50%) and CCR (completeness of cytoreduction) 0/1/2 score had significantly better OS rate than their respective counterparts. CONCLUSIONS: Ki-67 expression statue and CCR score could be employed as the prognosis prediction in patients with appendiceal mucinous adenocarcinoma.