Pre-operative tumour marker status predicts recurrence and survival after complete cytoreduction and hyperthermic intraperitoneal chemotherapy for appendiceal Pseudomyxoma Peritonei: Analysis of 519 patients

[Incidental finding of appendiceal mucinous neoplasms]

Low-grade appendiceal mucinous neoplasms (LAMN) are rare and are diagnosed in at least 0.13% of appendectomies in Germany, although significant underreporting is likely. Perforation of the tumors can result in abdominal mucinous collections, so-called pseudomyxoma peritonei (PMP). The challenge in the treatment of LAMN is the adequate approach to the incidental finding of these tumors. If a mucinous neoplasm is preoperatively suspected in cases of an acute condition, usually appendicitis, it must be weighed up whether a conservative approach is justifiable or whether immediate appendectomy is necessary. If this is the case, an intraoperative perforation of the appendix must be avoided and the complete abdominal cavity must be inspected for mucin deposits. If conservative treatment is possible, further treatment should take place at a specialized center. If the neoplasm is first found incidentally during surgery, perforation of the appendix should also be avoided and the entire abdominal cavity should be inspected for a PMP. If a PMP is present cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) should be performed in a specialized center. If LAMN are found during the postoperative histological work-up, it should be evaluated whether a perforation was present and mucin collections are noted in the surgical report. In the case of LAMN without evidence of a PMP, appendectomy is the adequate treatment. In cases of intra-abdominal mucinous collections, samples should be taken and further treatment should be performed at a center with sufficient expertise. An ileocecal resection or oncological hemicolectomy is not indicated. After adequate treatment, all patients should receive a follow-up using cross-sectional imaging (preferably magnetic resonance imaging, MRI) and determination of the tumor markers CEA, CA 19-9 and CA 125.

Appendiceal Mucinous Neoplasms: From Clinic to Pathology and Prognosis

Appendiceal mucinous neoplasms have been classified differently over time causing confusion when comparing results between working groups in this field and establishing a prognosis of the disease. A historical perspective of the different classification systems of these tumors is essential for the understanding of the evolution of concepts and histopathological definitions that have led up to the present moment. We carried out a systematic review of the pathological classifications of appendiceal mucinous tumors and how they have included the new criteria resulting from clinical and pathological research. The latest classifications by PSOGI and AJCC 8th edition Cancer Staging have made a great effort to incorporate the new pathological descriptions and develop prognostic groups. The introduction of these new classification systems has posed the challenge of verifying how they adapt to our casuistry and which one defines best the prognosis of our patients. We reclassified our series of patients treated for mucinous appendiceal tumors with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy following the PSOGI and the AJCC 8th edition criteria and concluded that both classifications correspond well with the OS and DFS of these patients, with some advantage relative to the PSOGI classification due to a better histopathological description of the different groups.

Analysis of appendiceal neoplasms in 1,423 appendectomy specimens: a 10-year retrospective cohort study from a single institution

OBJECTIVE

This study aimed to reveal the incidence, clinicopathological, and oncological outcomes of appendiceal neoplasms.

METHODS

This is a retrospective cohort study from a single institution. Patients with a pathological diagnosis of malignancy who underwent appendectomy between January 2011 and 2021 were included in the study, and groups were formed according to pathological type. Clinical, pathological, and oncological results were compared in these groups.

RESULTS

The incidence of neoplasia was 2.38% (n=34) in a cohort of 1,423 appendectomy cases. Of the cases, 56% (n=19) were female. The median age in the entire cohort was 55.5 (range: 13-106) years. In the cohort, the rate of neuroendocrine tumor mucinous cystadenoma adenocarcinoma, and low-grade appendiceal mucinous neoplasm, according to the American Joint Committee on Cancer classification of appendiceal neoplasms, was 32.3% (n=11), 26.4% (n=9), 26.4% (n=9), and 14.7% (n=5), respectively. Neuroendocrine tumor patients (median age: 35 years) were younger than the other groups (p=0.021). Secondary complementary surgery was performed in 66.7% (n=6) of adenocarcinoma patients and 27.3% (n=3) of neuroendocrine tumor patients. Right hemicolectomy was performed in all neuroendocrine tumor patients requiring secondary surgery, while right hemicolectomy was performed in three adenocarcinoma patients and cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in three adenocarcinoma patients. After a median follow-up of 44.4 months (95% confidence interval: 18.6-70.1), the mean survival rate was 55% in appendiceal adenocarcinoma patients compared to 100% in neuroendocrine tumor patients.

CONCLUSION

Appendiceal neoplasms are rare but remain an important cause of mortality. Appendiceal adenocarcinomas are associated with poorer oncological outcomes compared to other neoplasms.

Prognostic significance of the immuno-peritoneal cancer index in peritoneal metastatic patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

PURPOSE

A valid comparison of immune function among different patients with different primary pathologies or even with different tumour burdens requires the common use of a reliable assessment of the patient's condition. The combined immuno-PCI system can translate a complex clinical situation into a simple point value to improve postoperative outcomes to assess the prognostic significance of combined immuno-PCI in peritoneal metastatic patients treated with cytoreductive surgery(CRS) and hyperthermic intraperitoneal chemotherapy(HIPEC).

PATIENTS AND METHODS

Four hundred twenty-four patients from the prospectively maintained database of Dokuz Eylul University Peritoneal Surface Malignancy Center were retrospectively analysed. In addition to the demographic findings and the well-known clinicopathologic factors, several systemic inflammation-based prognostic scores, including the modified Glasgow prognostic score (mGPS), CRP-albumin ratio (CAR), neutrophil-lymphocyte ratio (NLR), neutrophil-thrombocyte ratio (NTR), and thrombocyte count, were all searched and stratified into scoring categories as prognostic determinants of surgical complications, final oncologic outcomes, recurrent disease, disease-free survival (DFS), and overall survival (OS). ROC analyses were performed, and cut-off values were obtained for all immune parameters by using the Youden index method.

RESULTS

There were 314 (74%) women and 110 (26%) men. The median age was 56 (ranging from 18 to 86) years. The most frequent sites of peritoneal metastasis were colorectal (n = 204; 48%) and gynaecologic carcinomas (n = 187; 44%). Thirty-three patients (8%) had primary malignant peritoneal mesothelioma. The median follow-up was 37.8 (ranging from 1 to 124) months. The overall survival was 51.7%. The 1-year, 3-year, and 5-year survival rates were estimated as 80%, 48.4%, and 32.6%, respectively. PCI-CAR-NTR (1 to 3) (p < .001) scoring was an independent prognostic factor for DFS. In a Cox backwards regression analysis, anastomotic leak (p = .002), completeness of cytoreduction (p = .0014), number of organ resections (p = .002), lymph node involvement (p = .003), and PCI-CAR-NTR (1 to 3) scoring (p = .001) were found to be independently significant prognostic factors for overall survival.

CONCLUSION

The PCI is a reliable and consistently valid prognostic factor to evaluate the tumour burden and tumour extent in patients treated with CRS/HIPEC. Staging the host by combining the PCI with an immunoscore may help to improve the outcomes of complications and overall survival in these complex cancer patients. The aggregate maximum immuno-PCI tool may be a better prognostic measure for outcome evaluation.

Development and Validation of Nomograms to Predict Survival in Patients Undergoing Complete Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei of Appendiceal Origin

Importance

Pseudomyxoma peritoni, a rare condition characterized by mucinous ascites and peritoneal deposits, mainly originates from a ruptured mucinous appendix tumor and is considered an indolent disease but can progress and become fatal. Optimal treatment to improve cure and survival rates involves complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Accurate predictive models are useful in supporting and informing treatment strategies and stratifying patient follow-up.

Objective

To evaluate the prognostic significance of clinically important variables and generate validated nomograms to predict overall (OS) and disease-free survival (DFS) following CCRS and hyperthermic intraperitoneal HIPEC for pseudomyxoma peritonei (PMP) of appendiceal origin.

Design, Setting, and Participants

This retrospective study used prospectively collected data on patients who had cytoreductive surgery (CRS) and HIPEC in a single institution between 1994 and 2018. The cohort was randomly allocated into development (70%) and validation (30%) sets. Univariate and multivariate analyses were performed with Cox proportional hazards regression.

Main Outcomes and Measures

A prediction model was developed with significant prognostic factors identified by multivariate analysis. The model's prognostic performance was evaluated with the concordance index (C index). The nomogram was calibrated by comparing the predicted and observed probabilities.

Results

Of 2637 CRS and HIPEC operations, 1102 patients (female, 64.4%; median age [IQR], 57.0 [48.0-66.0] years) (41.8%) had CCRS for PMP of appendiceal origin. Elevated tumor markers, peritoneal carcinomatosis index, gastrectomy, and tumor grade were independent predictive factors for DFS. Gender, age, elevated tumor makers, peritoneal carcinomatosis index, and tumor grade influenced OS. The nomograms were generated with respective prognostic factors. The nomograms showed good performance in predicting survival. Median OS of the cohort was 16.5 years (95% CI, 13.7-19.2) with a 5-year probability of survival of 80.2%. The median DFS was 10.3 years (95% CI, 7.2- 13.3) and the 5-year probability of recurrence-free survival was 60.5%.

Conclusions and Relevance

Clinically important independent predictors for survival and recurrence were selected to develop the nomograms for OS and DFS. These 2 nomograms are user friendly and useful tools for patient management with clinical trial design applications.

Pseudomyxoma peritonei induced by a well-differentiated appendicular mucinous adenocarcinoma: An uncommon cause of isolated ascites in a young man patient

Pseudomyxoma peritonei (PMP) remains difficult to diagnose and has a reserved prognosis. Pseudomyxoma peritonei is a rare entity, of appendicular origin in the majority of cases. Its clinical symptomatology is not specific, and the diagnosis is evoked by imaging and surgery and confirmed by histology.

Prognostic Factors in Pseudomyxoma Peritonei with Emphasis on the Predictive Role of Peritoneal Cancer Index and Tumor Markers

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare peritoneal condition where mucus-secreting tumorous cells progressively produce a thick, gelatin-like substance. The prognosis of patients with PMP is determined by the degree of cellularity within the mucin (low-grade (LAMN) vs. high-grade (HAMN) histologic features) and by the extent of the disease.

METHODS

Prognostic relevance of tumor markers CA19-9 and CEA, gender, Peritoneal Cancer Index (PCI), and completeness of cytoreduction (CC) after cytoreductive surgery were evaluated on 193 consecutive PMP patients, based on a retrospective analysis of prospectively gathered data from a German tertial referral center.

RESULTS

We demonstrated that low PCI, CC0 status, low-grade histology, and female gender were independent positive prognostic factors for both overall survival (OS) and progression-free survival (PFS). Furthermore, LAMN patients with achieved CC0 status show significantly better OS and PFS compared to those with CC1 status (p = 0.0353 and p = 0.0026 respectively). In contrast, the duration and drug of hyperthermic intraperitoneal chemotherapy (HIPEC) were not prognostic in any comparison. Increased CA19-9 and CEA levels were significantly associated with HAMN cases, but also predicted recurrence in patients with low-grade histologies.

CONCLUSION

Our study confirmed the prognostic role of tumor markers and emphasized the importance of CC status and PCI in a large cohort of PMP- and LAMN patients.

Serum and ascites tumor markers in the diagnostic and prognostic prediction for appendiceal pseudomyxoma peritonei

BACKGROUND

To investigate the expression of carcinoembryonic antigen (CEA), cancer antigen 199 (CA199) and CA125 in serum and ascites of appendiceal pseudomyxoma peritonei (PMP) patients relative to their diagnostic and predictive value.

METHODS

The study comprised 183 patients with pathologically confirmed appendiceal PMP, enrolled from May 2012 to June 2020, in Aerospace Center Hospital. Serum and ascites tumor markers were obtained, and their diagnostic values were compared by receiver operating characteristic (ROC) curves. The prognostic factors of appendiceal PMP with different pathologic subgroups were calculated by univariate and multivariate Cox proportional hazard regression models.

RESULTS

There were significant differences between the numbers of patients with positive CEA and CA199 in serum vs. ascites: p = 0.034 in CEA and p = 0.006 in CA199, respectively. The sensitivities with optimal cut-off values for ascites markers of CEA, CA199 and CA125 were 83.5%, 88.9% and 72.6%, respectively. CEA in ascites showed significant difference in the diagnosis of appendiceal PMP (p = 0.000); the areas under the ROC curves (AUROCs) and specificity were 0.725, 70.7%, respectively. Univariate analysis showed that the higher the ascites tumor markers, the poorer the survival (p = 0.014). Multivariate analysis indicated that completeness of cytoreduction (CCR), ascites CEA and pathological grade were independent risk factors for overall survival (OS).

CONCLUSION

CEA in ascites can be used to help specify the origin of PMP. Furthermore, elevation of ascites CEA, high pathological grade and incomplete cytoreduction predicted poor prognosis of appendiceal PMP.

Diagnostic and Therapeutic Algorithm for Appendiceal Tumors and Pseudomyxoma Peritonei: A Consensus of the Peritoneal Malignancies Oncoteam of the Italian Society of Surgical Oncology (SICO)

Aim: Pseudomyxoma peritonei (PMP) is an uncommon pathology, and its rarity causes a lack of scientific evidence, precluding the design of a prospective trial. A diagnostic and therapeutic algorithm (DTA) is necessary in order to standardize the disease treatment while balancing optimal patient management and the correct use of resources. The Consensus of the Italian Society of Surgical Oncology (SICO) Oncoteam aims at defining a diagnostic and therapeutic pathway for PMP and appendiceal primary tumors applicable in Italian healthcare. Method: The consensus panel included 10 delegated representatives of oncological referral centers for Peritoneal Surface Malignancies (PSM) affiliated to the SICO PSM Oncoteam. A list of statements regarding the DTA of patients with PMP was prepared according to recommendations based on the review of the literature and expert opinion. Results: A consensus was obtained on 33 of the 34 statements linked to the DTA; two flowcharts regarding the management of primary appendiceal cancer and peritoneal disease were approved. Conclusion: Currently, consensus has been reached on pathological classification, preoperative evaluation, cytoreductive surgery technical detail, and systemic treatment; some controversies still exist regarding the exclusion criteria for HIPEC treatment. A shared Italian model of DTA is an essential tool to ensure the appropriateness and equity of treatment for these patients.

Prognostic prediction of preoperative nutritional status in low-grade appendiceal mucinous neoplasms

To describe the preoperative nutritional status of Low-grade Appendiceal Mucinous Neoplasms (LAMNs) and identify prognostic factors for survival. Medical records from 165 patients with LAMNs who attended the Aerospace Center Hospital, Beijing, China between January 2017, and December 2018 were retrospectively reviewed. Survival analysis was performed with the Kaplan-Meier method, the log-rank test, and a Cox proportional hazards model. Among 165 patients, 59 (36%) were male and 106 (64%) were female. Patient's median age was 58 years (range 20 to 78 years). Univariate analysis indicated that gender, weight loss, prior surgical score (PSS), red blood cell, albumin, peritoneal cancer index (PCI), completeness of cytoreduction (CCR), and hyperthermic intraperitoneal chemotherapy (HIPEC) were related to prognosis. Multivariate analysis showed that PSS, CCR and HIPEC were independent predictors of prognosis. The preoperative nutritional status of patients plays an important role in predicting prognosis. Patients can benefit from a complete cytoreductive surgery (CCRS) and HIPEC in an experienced institution for the first medical treatment.

A proposal for changing nomenclature from pseudomyxoma peritonei (PMP) to abdomino-peritoneal mucinous carcinoma (APM) based on its long journey and experience from tertiary oncology center in India

Introduction

Pseudomyxoma peritonei (PMP) is a generalized term, usually known as “jelly belly” since 1884. Incidence is very low, 1–3 per million people per year. Because of its indolent nature, it is usually diagnosed at an advanced stage, thereby impacting the quality of life. The 5-year survival rate varies from 23 to 86% in world literature. Even 10 years and 20 years of survival have been described. With our experience, we like to propose rename of PMP as abdomino-peritoneal mucinous carcinoma (APM) as we strongly feel the time has come to specify the term and standardize the management strategy.

Methodology

In the premier institute of India and as a tertiary referral center, we experienced the maximum number of advanced cases of APM. From 2012 to 2021, we analyzed all the APM patients based on a prospectively maintained computerized database in the department of surgical oncology and found the reasons for renaming from this traditional one.

Results

We included a total of 87 patients who underwent surgical intervention. Thirty-five patients underwent cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC), and 52 patients underwent debulking. In CRS-HIPEC patients, CC-0 was achieved in 28 patients (80%), CC-1 in 4 patients (11.4%), and CC-2 in 3 patients (8.6%). Palliative intent HIPEC was done in 3 patients (8.6%). Clavien-Dindo grade III and IV morbidity was observed in 18.8% of patients with 90 days mortality of 5.7%.

Conclusion

With our long-term experience and advancement of scientific evidence, we like to propose a new name for PMP as APM. We strongly believe this paper will give a clear picture of this rare disease and standard management outlines.

Comprehensive Understanding and Evolutional Therapeutic Schemes for Pseudomyxoma Peritonei: A Literature Review

Pseudomyxoma peritonei is an infrequent solid tumor in clinical practice. The low morbidity and deficient understanding of this mucus-secreting malignant disease increase the risks of delayed identification or uncontrollable deterioration. In quite a lot cases, patients go through complete cytoreduction surgery and hyperthermic intraperitoneal chemotherapy could receive a long time survival over 5 years. But the recurrence rate is also hard to overlook. Unlike other types of cancer, the standard treatment for this considerable groups has not been confirmed yet. With the advanced medical progression, studies have been carrying out based on pathogenesis, biological characters, and mutated gene location. All but a few get statistical survival benefits, let alone the breaking progress on research or therapeutic practice in the field. We try to give a comprehensive exposition of pseudomyxoma peritonei around the epidemiology, radiologic features, clinical manifestation, present treatment and promising schemes, hoping to arise much attention and reflection on the feasible solutions, especially for the recrudescent part.

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.

Prognostic Impact of Pathology, Cytoreduction, and Tumor Markers in Pseudomyxoma Peritonei

INTRODUCTION

The pathologic classification of pseudomyxoma peritonei is controversial. This study aimed to standardize the histopathological evaluation of pseudomyxoma peritonei and identify the clinicopathological factors associated with survival.

METHODS

A pathologic review was performed to systematize the pathology report and verify the relationship between clinical features and survival. Terminology was based on the World Health Organization and Peritoneal Surface Oncology Group International definitions. Preoperative serum levels of carcinoembryonic antigen, CA19-9, and CA-125 were evaluated to determine their association with overall survival (OS) and ability to predict CC0-1 cytoreduction.

RESULTS

Among 109 patients with carcinomas resulting from primary appendiceal neoplasms, 72 had pseudomyxoma peritonei of appendiceal origin and underwent debulking surgery. CC0-1 cytoreduction and CC2-3 cytoreduction were achieved in 61% and 39% of patients, respectively. Patients in the CC0-1 and CC2-3 groups had an OS of 122.80 and 32.92 mo, respectively. The histologic grade was associated with CC0-1 cytoreduction; however, it did not influence OS. Patients with CC0-1 cytoreduction, acellular mucin, and low-grade lesions had better disease-free survival. Higher preoperative CA19-9 levels were associated with poor OS. Normal carcinoembryonic antigen values were associated with 100% sensitivity for predicting CC0-1. CA19-9 levels of 625 U/mL were associated with a low possibility of predicting CC0-1.

CONCLUSIONS

Histologic grades are associated with disease-free survival when CC0-1 cytoreduction is achieved. Normal preoperative CA19-9 levels were associated with a better OS. CC0-1 cytoreduction is the main determinant of longer survival.

Overall Survival is More Closely Associated with Peritoneal than Primary Appendiceal Pathological Grade in Pseudomyxoma Peritonei with Discordant Pathology

BACKGROUND

The WHO classification of mucinous appendix neoplasms and pseudomyxoma peritonei (PMP) describes low- and high-grade histology and is of prognostic importance. The metastatic peritoneal disease grade can occasionally be different from the primary appendix tumor. This analysis aimed to report outcomes from a high-volume center in patients with pathological discordance.

METHODS

This was a retrospective analysis of prospective data of patients treated by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for PMP at a single institution between January 2016 and December 2020. Reporting was by pathologists with a special interest in peritoneal malignancy. Discordant pathology was classified as a low-grade primary appendix tumor with high-grade peritoneal disease, or a high-grade primary appendix tumor with low-grade peritoneal disease. Outcomes analyzed were overall and recurrence-free survival, and Kaplan-Meier survival curves and the log-rank test were used to analyze the outcomes.

RESULTS

Between 2016 and 2020, 830 patients underwent CRS and HIPEC for PMP, of whom 37 (4.4%) had discordant pathology. The primary appendix tumors were low-grade in 23 patients and high-grade in 14 patients. The median Peritoneal Cancer Index (PCI) was significantly higher in patients with a low-grade primary tumor (31 vs. 16; p = 0.001), while complete cytoreduction (CC0/1) was achieved in 31/37 (83.8%) patients. The median follow-up was 19 months. Overall survival was worse in those with high-grade peritoneal disease (p = 0.029), whereas recurrence-free survival was similar in both groups (p = 0.075).

CONCLUSION

In PMP with pathological discordance, the peritoneal disease grade influences prognosis and survival.

Prevalence of Carcinoma in Appendectomy Specimens for Patients Presenting With Acute Appendicitis: A Single-Center Study

Introduction Acute appendicitis is the most common general surgical emergency globally. Its etiology includes the presence of luminal obstruction by faecoliths, lymphoid hyperplasia, impacted stool, and rarely by appendiceal or caecal cancer. Malignancy related to acute appendicitis is usually seen in the older age group. Aim To identify the subset rate of patients operated for acute appendicitis who have appendiceal carcinoma and analyze the outcome of their post-operative management. Material and methods A retrospective study of a cohort of 529 patients aged > 40 diagnosed with acute appendicitis with subsequent appendectomy in the period between 1 January 2014 and 31 December 2019 at Basildon and Thurrock University Hospital, Essex, United Kingdom was conducted. We analyzed the clinical data of the cohort including demographic information, diagnosis, pre-operative imaging, histological diagnosis as well as post-operative management where indicated. Results The median age of patients was 54.5 years (range 40-92). The male to female ratio in the appendicectomy cohort was 1:1.1. About 45% were aged 40-49 years, 24.8% were aged 50-59 and 30.2% were ≥60 years. Post-operative histology revealed acute appendicitis in 82.4% of the group. In 11% of the patients, the histology revealed the presence of other benign pathology as mucocele of the appendix, acute diverticulitis, follicular hyperplasia, and fibrous obliteration. The diagnosis of appendicular malignancy was seen in 1.9%. Conclusion Incidental appendiceal cancers in the resected specimens after acute appendicitis are rare but may be associated with a poor prognosis. It is recommended to consider such diagnosis in particular when dealing with acute appendicitis in older patients with longer symptom history, and in presence of peri-appendicular mass.

Nomogram to predict overall survival of patients with pseudomyxoma peritonei of appendiceal origin: A retrospective cohort study

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare disease, with the rate of overall survival (OS) influenced by many factors. The present study aimed to define independent predictors and establish a nomogram for individual risk prediction in PMP patients.

METHODS

One hundred forty-seven PMP patients were consecutively included between June 1, 2013, and November 22, 2019. The log-rank test was used to compare the OS rate between groups; subsequently, variables with p < .10 were subjected to multivariate Cox modeling for defining independent prediction indicators. Finally, a nomogram was established based on independent prognosticators and assessed for internal validation.

RESULTS

Multivariate Cox analysis showed that D-dimer level, carbohydrate antigen (CA) 125 level, CA 19-9 level, degree of radical surgery, and histological grade were all independently associated with OS in PMP patients. A nomogram was plotted and underwent internal validation. The discrimination ability of the nomogram revealed a good predictive ability as indicated by the C-index value (0.825), and calibration plots confirmed good consistency between the predicted and observed survival probabilities.

CONCLUSIONS

Five independent prognostic factors for predicting the survival of PMP patients were identified, and the nomogram based on these independent indicators showed a reasonable discrimination ability for individual risk prediction.

Nomogram to Predict Incomplete Cytoreduction for Pseudomyxoma Peritonei

BACKGROUNDS

The completeness of cytoreduction is one of the most important prognostic factors for patients with pseudomyxoma peritonei (PMP). To date, no nomograms have been established to predict incomplete cytoreduction (IC) for patients with PMP. The current study therefore proposed a nomogram to predict individual IC risk for PMP patients.

METHODS

Between 1 June 2013, and 22 November 2019, 144 consecutive PMP patients who underwent cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for the first time in our center were included in a retrospective study. Possible predictors of cytoreducibility were analyzed using logistic regression modeling to predict IC for PMP patients. A nomogram was developed based on the multivariate analysis and further investigated for internal validation.

RESULTS

After CRS, the 144 participants were divided into complete CRS (CCRS) (n = 46) and IC (n = 98) subgroups. Four independent predictors (sex, disease duration, anemia, and carbohydrate antigen 19-9 (CA 199)) were included in the prediction model. Then, a nomogram predicting IC was established based on the aforementioned variables, which demonstrated good predictive accuracy (C-index, 0.837; 95 % confidence interval [CI], 0.764-0.894). The predicted probability was close to the actual observed outcome according to the calibration plot.

CONCLUSIONS

The current work led to the development of a nomogram capable of predicting IC for PMP patients who demonstrated good performance. Risk stratification by the established nomogram had ability to optimize individual IC prediction and help physicians to establish meticulous preoperative plans.

Appendiceal pseudomyxoma peritonei: predictors of recurrence and iterative surgery

AIM

Appendiceal pseudomyxoma peritonei (PMP) is a rare entity, with recurrence rates up to 26% despite optimal cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Evidence specific to PMP originating from non-infiltrative appendiceal mucinous neoplasms (low grade - LAMN and high grade - HAMN) is lacking. The aim of this study was to identify patterns of recurrence and predictive factors for patients appropriate for iterative surgery.

METHOD

A bi-institutional retrospective analysis was performed on patients undergoing complete cytoreduction and HIPEC for PMP derived from perforated LAMN or HAMN. Multivariate logistic regression was performed to identify independent predictors for re-do CRS. Five-year overall survival (OS) was stratified according to surgical intervention, and 5-year disease-free survival (DFS) was stratified according to histological PMP grade. Cox regression analysis was performed to identify independent predictors for OS and DFS.

RESULTS

Sixty of 239 (25.1%) patients developed peritoneal recurrence between 2007 and 2020. The median time to recurrence was 20.7 months. The risk of disease recurrence was highest with high-grade PMP (P <0.001) and increasing PCI (P <0.001). Patients with high-grade histology from their index procedure and aged over 60 years were less likely to be offered iterative surgery on multivariate analysis. Patients who underwent iterative CRS and HIPEC had a 5-year survival of 100%.

CONCLUSION

Iterative CRS and HIPEC is feasible in selected patients with recurrent PMP, displaying good oncological outcomes. Age, index histology and level of abdominal quadrant involvement are predictive of proceeding to re-do surgery.

Clinicopathological Characteristics and Prognostic Prediction in Pseudomyxoma Peritonei Originating From Mucinous Ovarian Cancer

Objective

To describe the clinicopathological characteristics of mucinous ovarian cancer (MOC)-derived pseudomyxoma peritonei (PMP) and identify prognostic factors for survival.

Methods

Medical records from patients with MOC-derived PMP who attended the Aerospace Center Hospital, Beijing, China between January 2009, and December 2019 were retrospectively reviewed. Survival analysis was performed with the Kaplan-Meier method, the log-rank test, and a Cox proportional hazards model.

Results

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for PMP originating from MOC were performed on 22 patients, who had a median age of 52 years at the time of surgery. At the last follow-up in June 2020, 9 (41%) patients were still alive. Median OS was 12 months (range, 1 to 102 months), and the 2-, 3-, and 5-year survival rates were 23, 9, and 5%, respectively.

Conclusion

Histopathologic subtype and PCI may be applied as predictors of prognosis in patients with MOC-derived PMP. Patients with high-grade disease could benefit from completeness of cytoreduction (CCR) 0/1.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the management of peritoneal surface malignancies - An evidence-based review

BACKGROUND

Traditionally, peritoneal surface malignancies (PSM) were considered terminal diseases because of their advanced nature, therefore, systemic chemotherapy was given with palliative intent only. As a result, very poor survival outcomes were observed. But with the introduction of complete Cytoreductive surgery (CRS) and Hyperthermic intraperitoneal chemotherapy (HIPEC), the scenario has changed dramatically.

METHODOLOGY

An objective electronic database search was performed in Pubmed, NLM Catalog, Google scholar, Bookshelf, and Pubmed Central published in the time period from 2000 till 2020. All the randomized studies were included. In the absence of randomized studies, both prospective and retrospective studies were included. The outcomes of HIPEC were measured in terms of median survival, disease-free survival, overall survival, complications and drug toxicities.

RESULTS

CRS and HIPEC are considered the standard of care for PMP and MPM even in the absence of level 1 evidence due to lack of an effective alternative treatment. In colorectal and gastric cancer, several phase-three trials are showing overall survival benefit in selected cases while there is a prophylactic and palliative role of HIPEC in gastric cancer. Three reported phase 3 trials showed positive results in ovarian cancer. In peritoneal sarcomatosis, the role of HIPEC is yet to be proven.

CONCLUSION

The patient selection is the key to the successful outcomes after HIPEC. HIPEC should be performed by the experienced surgeons in specialized centres with a strong critical care and intensive care support to reduce the morbidity and mortality. Ongoing trials and future directions will prove to be an indispensable arm in the oncological armamentarium.

Pseudomyxoma Peritonei Originating from Transverse Colon Mucinous Adenocarcinoma: A Case Report and Literature Review

Background

Pseudomyxoma peritonei (PMP) is a rare neoplasm involving the peritoneum. Most PMPs are low-grade appendicular mucinous neoplasms (LAMNs). There have been no reports of PMP originating from a transverse colonic mucinous adenocarcinoma and causing metastatic mucinous adenocarcinoma. Case Presentation. We report a 46-year-old woman who presented with a right abdominal mass of more than 4-month duration. Transverse colonic mucinous adenocarcinoma, PMP, and ovarian metastatic mucinous adenocarcinoma were diagnosed. The patient's diet was normal, and she had no abdominal pain or bloating. The abdomen mass increased in the month before treatment. After chemotherapy, the transverse colon mass and ovarian giant cyst were resected and about 2000 mL of gelatinous tumor tissue was removed. Postoperative histology confirmed PMP from the transverse colonic mucinous adenocarcinoma, ovarian metastatic mucinous adenocarcinoma, and mesocolon metastatic cancer. Multiple lung metastases appeared 8 months after surgery. The patient died 29 months after surgery because of an inability to eat and poor nutrition. A systematic literature review of the management and outcome of all known similar cases is also presented.

Conclusions

This is the first report of PMP originating from a transverse colonic mucinous adenocarcinoma. It was diagnosed during resective surgery, involved ovarian metastasis, and survival was short. We did an extensive literature review in order to describe the clinical characteristics, histopathological findings, genetic profile, and potential treatments of PMP caused by nonappendiceal mucinous adenocarcinoma.

Updates in Appendix Pathology: The Precarious Cutting Edge

Mucinous appendiceal tumors include low-grade appendiceal mucinous neoplasm, high-grade appendiceal mucinous neoplasm, and mucinous adenocarcinoma. Nonmucinous adenocarcinomas are less frequent. Recent consensus guidelines and the latest edition of the World Health Organization classification will allow consistent use of agreed nomenclature. Accurate diagnosis is important not only for patient management but also to allow comparison of results between centers and tumor registries. Serrated polyps are the most common benign polyp in the appendix. They need to be distinguished from low-grade appendiceal mucinous neoplasm, which can also mimic other benign conditions. Goblet cell adenocarcinomas are a distinctive type of appendiceal neoplasm.

Improved Outcome Prediction for Appendiceal Pseudomyxoma Peritonei by Integration of Cancer Cell and Stromal Transcriptional Profiles

In recent years, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have substantially improved the clinical outcome of pseudomyxoma peritonei (PMP) originating from mucinous appendiceal cancer. However, current histopathological grading of appendiceal PMP frequently fails in predicting disease outcome. We recently observed that the integration of cancer cell transcriptional traits with those of cancer-associated fibroblasts (CAFs) improves prognostic prediction for tumors of the large intestine. We therefore generated global expression profiles on a consecutive series of 24 PMP patients treated with CRS plus HIPEC. Multiple lesions were profiled for nine patients. We then used expression data to stratify the samples by a previously published “high-risk appendiceal cancer” (HRAC) signature and by a CAF signature that we previously developed for colorectal cancer, or by a combination of both. The prognostic value of the HRAC signature was confirmed in our cohort and further improved by integration of the CAF signature. Classification of cases profiled for multiple lesions revealed the existence of outlier samples and highlighted the need of profiling multiple PMP lesions to select representative samples for optimal performances. The integrated predictor was subsequently validated in an independent PMP cohort. These results provide new insights into PMP biology, revealing a previously unrecognized prognostic role of the stromal component and supporting integration of standard pathological grade with the HRAC and CAF transcriptional signatures to better predict disease outcome.

Pseudomyxoma peritonei: visceral scalloping on CT is a predictor of recurrence after complete cytoreductive surgery

OBJECTIVES

Pseudomyxoma peritonei (PMP) is characterized by peritoneal dissemination of gelatinous ascites following rupture of a mucinous tumor. Treatment by cytoreductive surgery (CRS) has improved its prognosis. Although visceral scalloping, notably liver scalloping, on computed tomography (CT) is a typical feature of PMP, its prognostic value remains unknown. We aimed to investigate the efficacy of liver scalloping in predicting recurrence in PMP patients.

METHODS

Among 159 consecutive patients with PMP who had contrast-enhanced CT between September 2012 and December 2018, 64 treatment-naïve patients who subsequently underwent CRS with complete resection (i.e., completeness of cytoreduction score (CC)-0 or CC-1), were included in analysis. Presence of liver scalloping and maximum thickness of mucin deposition at the liver surface were evaluated on CT. Disease-free survival (DFS) was determined based on the combination of postoperative CT features and tumor marker values.

RESULTS

Median follow-up was 24.3 months. CT revealed liver scalloping in 40/64 (63.4%) patients. Kaplan-Meier analysis showed significantly shorter DFS in patients with scalloping than in those without (p = 0.001; hazard ratio, 4.3). In patients with scalloping, greater mucin deposition (thickness ≥ 20 mm) significantly correlated with poorer DFS (p = 0.042). In multivariate Cox proportional hazards regression including CC status, pathologic type, and tumor markers, the presence of scalloping independently and significantly correlated with DFS (p = 0.031).

CONCLUSIONS

Liver scalloping was an independent predictor even after adjusting for clinical covariates. The presence of liver scalloping can lead to a high recurrence rate after CRS.

KEY POINTS

• The presence of liver scalloping is a prognostic factor independent of histological grade and tumor markers. • Greater mucin deposition (thickness ≥ 20 mm at the liver surface) is associated with higher recurrence rates in patients with liver scalloping.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Preoperative Risk Score for Predicting Incomplete Cytoreduction: A 12-Institution Study from the US HIPEC Collaborative

BACKGROUND

For patients with peritoneal carcinomatosis undergoing cytoreductive surgery with heated intraperitoneal chemotherapy (CRS/HIPEC), incomplete cytoreduction (CCR2/3) confers morbidity without survival benefit. The aim of this study is to identify preoperative factors which predict CCR2/3.

METHODS

All patients who underwent curative-intent CRS/HIPEC of low/high-grade appendiceal, colorectal, or peritoneal mesothelioma cancers in the 12-institution US HIPEC Collaborative from 2000 to 2017 were included (n = 2027). The primary aim is to create an incomplete-cytoreduction risk score (ICRS) to predict CCR2/3 CRS utilizing preoperative data. ICRS was created from a randomly selected cohort of 50% of patients (derivation cohort) and verified on the remaining patients (validation cohort).

RESULTS

Within our derivation cohort (n = 998), histology was low-grade appendiceal neoplasms in 30%, high-grade appendiceal tumor in 41%, colorectal tumor in 22%, and peritoneal mesothelioma in 8%. CCR0/1 was achieved in 816 patients and CCR 2/3 in 116 patients. On multivariable analysis, preoperative factors associated with incomplete cytoreduction were male gender [odds ratio (OR) 3.4, p = 0.007], presence of ascites (OR 2.8, p = 0.028), cancer antigen (CA)-125 ≥ 40 U/mL (OR 3.4, p = 0.012), and carcinoembryonic antigen (CEA) ≥ 4.2 ng/mL (OR 3.2, p = 0.029). Each preoperative factor was assigned a score of 0 or 1 to form an ICRS from 0 to 4. Scores were grouped as zero (0), low (1-2), or high (3-4). Incidence of CCR2/3 progressively increased by risk group from 1.6% in zero to 13% in low and 39% in high. When ICRS was applied to the validation cohort (n = 1029), this relationship was maintained.

CONCLUSION

The incomplete cytoreduction risk score incorporates preoperative factors to accurately stratify the risk of CCR2/3 resection in CRS/HIPEC. This score should not be used in isolation, however, to exclude patients from surgery.

Short- and Long-Term Outcomes of Patients Requiring Gastrectomy During Cytoreductive Surgery and Intraperitoneal Chemotherapy for Lower-Gastrointestinal Malignancies: A Propensity Score-Matched Analysis

OBJECTIVES

This study was designed to assess the short- and long-term outcomes of gastric resection in cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) for lower gastrointestinal (GI) malignancies.

METHODS

Patients with adenocarcinoma and appendiceal mucinous neoplasms were included. Redo and incomplete cytoreductions were excluded. A total of 756 patients were identified. Of these, 65 underwent gastric resection, 11 underwent wedge, 43 distal, and 11 subtotal and total gastrectomy. Preoperative differences were assessed for and addressed with matching. Perioperative outcomes, overall survival (OS), and risk-free survival (RFS) were assessed in two analyses: first all gastric resections were included and the second excluded wedge resections. Subgroup analysis according to diagnosis subtype was conducted.

RESULTS

Demographic analysis revealed that markers of tumor aggression and poor nutrition were prevalent in the gastrectomy group. The matched analysis for gastric resections revealed higher rates of reoperation (38% vs. 22%, p = 0.028). After excluding wedge resections, increased rates of reoperation (40% vs. 22%, 0.019), grade 3/4 morbidity (76% vs. 59%, p = 0.036), and hospital stay (34 vs. 27 days, p = 0.012) were observed. For the unmatched cohort, OS (103 vs. 69 months, p = 0.501) and RFS (17 vs. 18 months, p = 0.181) for patients with CC = 0 were insignificantly different. In comparison for CC > 0, OS (31 vs. 83 months, p < 0.001) and RFS (9 vs. 20 months, p < 0.001) were significantly reduced in gastric resection. For the matched cohort, after excluding wedges, gastrectomy did not significantly decrease OS. However, RFS was decreased (11 vs. 20 months, p = 0.016).

CONCLUSIONS

Despite high postoperative morbidity, when complete cytoreduction is achieved, the need for gastric resection is not associated with inferior long-term outcomes.

Selection and Characteristics of Patients with Peritoneal Dissemination from Appendiceal Cancer with Exceptional/Poor Survival After CRS/HIPEC

BACKGROUND

Survival in peritoneal dissemination from appendiceal cancer after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) varies within each histopathologic subtype. Analyzing patients with unique responses may uncover the mechanisms behind their extreme outcomes. We proposed a method to identify retrospectively and to characterize patients who responded exceptionally well or very poorly within each histopathologic subtype.

METHODS

Retrospective review of patients with low-grade mucinous carcinoma peritonei (LGMCP), high-grade MCP (HGMCP), and HGMCP with signet ring cells (HGMCP-S) with complete CRS/HIPEC (CC-0/1) was performed. Patients were divided by recurrence status. Median follow-up was calculated for each. Exceptional responders (ExR) were defined as alive without recurrence after median follow-up of the nonrecurrent group. Poor responders (PoR) were defined as disease recurrence before median follow-up of the recurrent group. Perioperative characteristics were analyzed.

RESULTS

LGMCP, HGMCP, and HGMCP-S had 48 (41%), 19 (23%), and 7 (14%) ExR and 11 (10%), 20 (24%), and 20 (39%) PoR, respectively. All ExR had lower median PCI (26 vs. 36 [p = 0.004]; 13 vs. 33.5 [p < 0.001]; 3 vs. 29.5 [p = 0.001]). Fewer LGMCP and HGMCP ExR had abnormal tumor markers (36% vs. 90% [p = 0.003]; 22% vs. 74% [p = 0.003]). More HGMCP and HGMCP-S ExR had CC-0 (vs. CC-1) cytoreductions (84% vs. 50%, p = 0.041; 100% vs. 40%, p = 0.008).

CONCLUSIONS

Stratifying patients by recurrence status and follow-up time successfully selects ExR and PoR within each histopathologic subtype. Perioperative characteristics of ExR versus PoR differ across histopathologic subtypes, except for disease burden. Genetic analysis may further elucidate differences and aid in the development of novel targeted therapies.

Pseudomyxoma peritonei induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer: a case report and literature review

Background

Pseudomyxoma peritonei (PMP) is a disease involving the peritoneum characterized by the production of large quantities of mucinous ascites. PMP has a low incidence, is difficult to diagnose, and has a guarded prognosis. PMP induced by low-grade appendiceal mucinous neoplasm is extremely rare, and PMP accompanied by rectal cancer is even rarer.

Case presentation

We present a unique case of a 70-year-old male with PMP induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer. The patient’s clinical, surgical, and histologic data were reviewed. The patient had persistent distended abdominal pain without radiating lower back pain, abdominal distension for 1 month, and no exhaustion or defecation for 4 days. A transabdominal ultrasound-guided biopsy was performed on the first day. The patient received an emergency exploratory laparotomy because of increased abdominal pressure. We performed cytoreductive surgery, enterolysis, intestinal decompression, special tumour treatment and radical resection of rectal carcinoma. The postoperative course was uneventful. The postoperative histological diagnoses were PMP, low-grade appendiceal mucinous neoplasm and rectal medium differentiated adenocarcinoma. At the 1-year follow-up visit, no tumour recurrence was observed by computed tomography (CT). We also performed a literature review.

Conclusions

We should be aware that PMP can rarely be accompanied by rectal cancer, which represents an easily missed diagnosis and increases the difficulty of diagnosis and treatment. Additionally, there are some typical characteristics of PMP with respect to diagnosis and treatment.

Survival after complete cytoreductive surgery and HIPEC for extensive pseudomyxoma peritonei

INTRODUCTION

The optimal treatment for pseudomyxoma peritonei (PMP) combines complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Yet, achieving CRS is challenging in the case of extensive involvement of the peritoneal cavity and the survival benefit in this setting remains uncertain. The present study evaluated the surgical outcomes according to the peritoneal extent.

METHODS

Between 1992 and 2014, 245 patients underwent CRS and HIPEC for PMP in our institution. Their characteristics were reviewed using a prospective database. Extensive PMP was defined as a peritoneal cancer index (PCI) ≥ 28. Sixty-one patients with extensive PMP were compared to 184 with non-extensive PMP.

RESULTS

Severe complications were more frequent in the extensive group (46% vs. 23%, p < 0.001) but the post-operative mortality was not significantly different (8% vs. 3%, p = 0.1). The 5-year disease-free survival reached 45% in the extensive and 78% in the non-extensive group (p < 0.0001). The 5-year overall survival was 70% and 90% in the extensive and non-extensive group respectively (p < 0.021).

CONCLUSION

CRS with HIPEC offers prolonged survival even in the case of extensive PMP. Because of the high rate of surgical morbidity in the extensive group, patients should be carefully selected.

Factors influencing long-term survival after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei originating from appendiceal neoplasms

Background

Pseudomyxoma peritonei (PMP) is a rare disease, most commonly of appendiceal origin. Treatment consists of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS–HIPEC). The aim of this study was to identify prognostic factors for recurrence and survival.

Methods

This was an observational study using a prospectively designed database containing consecutive patients with PMP originating from the appendix, undergoing CRS–HIPEC at a tertiary referral centre between 1996 and 2015. Histopathological slides were reassessed. Cox regression was used for multivariable analyses.

Results

Of 225 patients identified, 36 (16·0 per cent) were diagnosed with acellular mucin, 149 (66·2 per cent) had disseminated peritoneal adenomucinosis (DPAM) and 40 (17·8 per cent) had peritoneal mucinous carcinomatosis (PMCA). The 5‐year overall survival (OS) rates were 93, 69·8 and 55 per cent respectively. Recurrence was observed in 120 patients (53·3 per cent), 39 of whom (17·3 per cent) were treated with a second CRS–HIPEC procedure. Factors independently associated with poor disease‐free survival were six or seven affected regions (hazard ratio (HR) 6·01, 95 per cent c.i. 2·04 to 17·73), incomplete cytoreduction (R2a resection: HR 1·67, 1·05 to 2·65; R2b resection: HR 2·00, 1·07 to 3·73), and more than threefold raised carcinoembryonic antigen (CEA) and/or carbohydrate antigen (CA) 19‐9 level (HR 2·31, 1·30 to 4·11). Factors independently associated with poorer OS were male sex (HR 1·74, 1·09 to 2·77), incomplete cytoreduction (R2a resection: HR 1·87, 1·14 to 3·08; R2b resection: HR 2·28, 1·19 to 4·34), and more than threefold raised CEA and/or CA19‐9 level (HR 2·89, 1·36 to 6·16).

Conclusion

CEA and CA19‐9 levels raised more than threefold above the upper limit identify patients with PMP of appendiceal origin and poorer survival.

A unique presentation of superinfected pseudomyxoma peritonei secondary to a low-grade appendiceal mucinous neoplasm

Background

Pseudomyxoma peritonei (PMP) is an uncommon condition characterized by diffuse mucinous material in the abdomen and pelvis, generally arising from a perforated epithelial neoplasm. Typically, the disease presents as suspected acute appendicitis, ovarian mass, abdominal distension, or ventral hernia. Our case represents a very rare presentation of superinfected PMP.

Case presentation

A 46-year-old female with a past medical history notable for depression, asthma, and uterine leiomyomas presented to an urgent care with 5 days of progressive abdominal pain, bloating, nausea, and subjective fevers. The patient had a diffusely tender abdomen, without peritonitis, was mildly tachycardic, and had a white blood cell count of 15 K. A CT of the abdomen/pelvis was consistent with PMP with a ruptured appendiceal mucocele versus PMP secondary to an adnexal ovarian neoplastic pathology with an infectious component. The patient initially improved on antibiotics but ultimately required two surgeries, the first of which controlled intraabdominal sepsis while the second permitted definitive management of PMP with cytoreductive surgery (CRS) and HIPEC.

Conclusion

Superinfected PMP is a rare entity with very few documented cases. A staged approach that incorporates clearing the peritoneal infection, with or without resection of the primary tumor, followed by rehabilitation and definitive surgery appears to be a safe and effective management strategy.

Outcomes in Peritoneal Dissemination from Signet Ring Cell Carcinoma of the Appendix Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is standard treatment for peritoneal dissemination from appendiceal cancer (AC); however, its role in high-grade histopathologic subtypes (high-grade mucinous carcinoma peritonei [HGMCP] and HGMCP with signet ring cells [HGMCP-S]) is controversial due to their aggressive behavior. This study analyzed clinical outcomes of high-grade AC after CRS/HIPEC.

METHODS

A prospective database of CRS/HIPEC procedures for HGMCP performed from 1998-2017 was reviewed. Perioperative variables and survival were analyzed.

RESULTS

Eighty-six HGMCP and 65 HGMCP-S were identified. HGMCP had more positive tumor markers (TM) (CEA/CA-125/CA-19-9) than HGMCP-S (63% vs 40%, p = 0.005). HGMCP had higher Peritoneal Cancer Index (32 vs 26, p = 0.097) and was less likely to have positive lymph nodes (LN) than HGMCP-S (28% vs 69%, p = < 0.001). Complete cytoreduction was achieved in 84% and 83%, respectively. PFS at 3- and 5-years was 59% and 48% for HGMCP vs 31% and 14% for HGMCP-S. Median PFS was 4.3 and 1.6 years, respectively (p < 0.001). OS at 3- and 5-years was 84% and 64% in HGMCP vs 38% and 25% in HGMCP-S. Median OS was 7.5 and 2.2 years, respectively (p < 0.001). LN negative HGMCP-S had longer median PFS and OS than LN positive HGMCP-S (PFS: 3.4 vs 1.5 years, p = 0.03; OS: 5.6 vs 2.1 months, p = 0.021).

CONCLUSIONS

The aggressive histology of HGMCP-S is associated with poor OS, has fewer abnormal TM, and is more likely to have positive LN. However, CRS/HIPEC can achieve a 5-year survival of 25%, which may improve to 51% with negative LN.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei in a liver-transplanted patient: a case report

Background

Diagnostic work-ups in transplanted immunosuppressed patients are a challenge as non-specific findings may be interpreted as transplant-related complications. If the disease in question is rare and slowly developing like pseudomyxoma peritonei (PMP), it is even more difficult. Cytoreductive surgery (CRS) and subsequent hyperthermic intraperitoneal chemotherapy (HIPEC) is the recommended treatment for PMP even with extensive peritoneal spread. CRS-HIPEC for PMP after liver transplantation (LTX) has not been described before.

Case presentation

A 48-year-old female patient with end-stage primary sclerosing cholangitis (PSC) underwent orthotopic LTX and subsequent pancreaticoduodenectomy after the finding of cholangiocarcinoma in situ in the native common bile duct. Ten years after the transplantation, she developed symptoms and signs suspected to represent graft-related complications. An extensive work-up revealed PMP. Upon reassessment, a cystic mass near the coecum could be seen on computed tomography scan 1 year after transplantation. The multidisiplinary team was hesitant to accept the patient for CRS-HIPEC because of extensive PMP and possible risk to the graft. However, she was eventually accepted and underwent the procedure. The Peritoneal Cancer Index (PCI) was 28 of 39, and surgical debulking was performed followed by HIPEC. The transplant control 2 months after surgery showed no harm to the graft.

Conclusions

Previous LTX should not exclude the possibility for CRS-HIPEC in PMP, even with extensive burden of disease.

The Role of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Appendiceal Tumors and Colorectal Adenocarcinomas

Peritoneal surface disease (PSD) has historically been used interchangeably with the term peritoneal carcinomatosis (PC) and has a dismal natural history. A variety of malignant pathologies, including colorectal and appendiceal primary tumors, can disseminate throughout the peritoneal cavity, leading to bowel obstruction and death. In general, peritoneal spread from high-grade appendiceal and colorectal primaries has the potential of hepatic and distant spread and best classified as PC. Low-grade appendiceal tumors are better categorized as PSD, due to low cellularity, high mucin production, and lack of potential spread outside the peritoneal cavity. Growing international experience with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) over the past 30 years has presented a therapeutic option to patients with PSD from colorectal and appendiceal tumors that can provide significant disease control, as well as potential for previously unattainable long-term survival. The proliferation of HIPEC centers and ongoing prospective trials are helping to standardize HIPEC techniques and patient selection.

Approach to pseudomyxoma peritonei

Pseudomyxoma peritonei (PMP) is a mucinous tumour of the appendix that spreads into the peritoneal cavity in the form of gelatinous deposits. The incidence of PMP is believed to be approximately 1-3 out of a million per year. Nonetheless, due to its indolent nature, it is usually discovered at an advanced stage and severely impacts quality of life. Curative treatment for PMP is complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). An extensive literature review was conducted searching EMBASE, MEDLINE, PubMed, and Google Scholar databases for PMP in aims to delineate a clinical approach to diagnosis and treatment. Literature was limited to the years 2007-2018. We found the 5-year overall survival with CRS and HIPEC estimated to be between 23%-82% and rates of major complications as high as 24%. Therefore, it is important to appropriately stage and select patients that should undergo CRS with HIPEC. Modalities like MDCT radiological scores have been shown to have sensitivity and specificity of 94% and 81%, respectively, in being able to predict resectability and survival. Despite treatment, the disease often recurs. Tumor markers have significant potential for establishing prognosis pre-operatively, and this paper will review the most recent evidence in support of them.

Glycomic Profiling Highlights Increased Fucosylation in Pseudomyxoma Peritonei

Pseudomyxoma peritonei (PMP) is a subtype of mucinous adenocarcinoma that most often originates from the appendix, and grows in the peritoneal cavity filling it with mucinous ascites. KRAS and GNAS mutations are frequently found in PMP, but other common driver mutations are infrequent. As altered glycosylation can promote carcinogenesis, we compared N-linked glycan profiles of PMP tissues to those of normal appendix. Glycan profiles of eight normal appendix samples and eight low-grade and eight high-grade PMP specimens were analyzed by mass spectrometry. Our results show differences in glycan profiles between PMP and the controls, especially in those of neutral glycans, and the most prominent alteration was increased fucosylation. We further demonstrate up-regulated mRNA expression of four fucosylation-related enzymes, the core fucosylation performing fucosyltransferase 8 and three GDP-fucose biosynthetic enzymes in PMP tissues when compared with the controls. Up-regulated protein expression of the latter three enzymes was further observed in PMP cells by immunohistochemistry. We also demonstrate that restoration of fucosylation either by salvage pathway or by introduction of an expression of intact GDP-mannose 4,6-dehydratase enhance expression of MUC2, which is the predominant mucin molecule secreted by the PMP cells, in an intestinal-derived adenocarcinoma cell line with defective fucosylation because of deletion in the GDP-mannose 4,6-dehydratase gene. Thus, altered glycosylation especially in the form of fucosylation is linked to the characteristic mucin production of PMP. Glycomic data are available via ProteomeXchange with identifier PXD010086.

A proposal of Brazilian Society of Surgical Oncology (BSSO/SBCO) for standardizing cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) procedures in Brazil: pseudomixoma peritonei, appendiceal tumors and malignant peritoneal mesothelioma

Cytoreductive surgery plus hypertermic intraperitoneal chemotherapy has emerged as a major comprehensive treatment of peritoneal malignancies and is currently the standard of care for appendiceal epithelial neoplasms and pseudomyxoma peritonei syndrome as well as malignant peritoneal mesothelioma. Unfortunately, there are some worldwide variations of the cytoreductive surgery and hypertermic intraperitoneal chemotherapy techniques since no single technique has so far demonstrated its superiority over the others. Therefore, standardization of practices might enhance better comparisons between outcomes. In these settings, the Brazilian Society of Surgical Oncology considered it important to present a proposal for standardizing cytoreductive surgery plus hypertermic intraperitoneal chemotherapy procedures in Brazil, with a special focus on producing homogeneous data for the developing Brazilian register for peritoneal surface malignancies.

Pseudomyxoma peritonei: natural history and treatment

Pseudomyxoma peritonei (PMP) is an uncommon disease characterised by mucinous ascites, classically originating from a ruptured low grade mucinous neoplasm of the appendix. The natural history of PMP revolves around the "redistribution phenomenon", whereby mucinous tumour cells accumulate at specific sites with relative sparing of the motile small bowel and to a lesser extent other parts of the gastrointestinal tract. Peritoneal tumour accumulates due to gravity and at the sites of peritoneal fluid absorption, namely, the greater and lesser omentum and the under-surface of the diaphragm, particularly on the right. The optimal treatment is complete macroscopic tumour excision termed cytoreductive surgery (CRS) combined with Hyperthermic Intra-Peritoneal Chemotherapy (HIPEC). Total operating time for complete CRS and HIPEC for extensive PMP is around 10 h and generally involves bilateral parietal and diaphragmatic peritonectomies, right hemicolectomy, radical greater omentectomy with splenectomy, cholecystectomy and liver capsulectomy, a pelvic peritonectomy with, or without, rectosigmoid resection and bilateral salpingo-oophorectomy with hysterectomy in females. A unique feature of low grade PMP, which differs from other peritoneal malignancies, includes slow disease progression, which may be asymptomatic until advanced stages. Additionally, very extensive disease with a high "PCI" (Peritoneal Carcinomatosis Index) may still be amenable to complete excision and cure. In cases where complete tumour removal is not feasible, maximum tumour debulking can still result in long-term survival in PMP. PMP is challenging, complex but nevertheless the most rewarding peritoneal malignancy amenable to cure by CRS and HIPEC.

The pre-operative neutrophil-lymphocyte ratio predicts overall and disease-free survival following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with pseudomxyoma peritonei of appendiceal origin

AIM

The neutrophil-lymphocyte ratio (NLR) and other inflammation-based scores have been used as a prognostic tool to predict survival in solid tumours including pseudomyxoma peritonei (PMP). The aim was to evaluate the prognostic value of this marker and risk stratify PMP patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

Retrospective analysis was conducted of a prospectively collected database of patients with PMP who underwent CRS and HIPEC between 1994 and 2015. The NLR was calculated by dividing the pre-operative neutrophil count by lymphocyte count. Predicted overall survival (OS) and disease-free interval (DFI) were calculated using a Kaplan-Meier survival model.

RESULTS

The study included 699 patients, stratified into four groups as defined by their NLR. Group A: 200 (28.6%) patients (NLR = 0.10-2.00), Group B: 160 (22.8%) patients (NLR = 2.10-2.78), Group C: 184 (26.3%) patients (NLR = 2.79-4.31) and Group D: 155 (22.2%) patients (NLR ≥ 4.32). The median follow-up for this cohort was 36 months. The predicted DFI was 132.2, 113.1, 84.4 and 47.9 months and the OS was 141.1, 117.6, 88.7 and 51.2 months for Groups A, B, C and D, respectively. As the NLR increases, there is a reduction in long-term survival.

CONCLUSION

The pre-operative NLR is cost effective and has equivalent prognostic value to pre-operative tumour markers for patients with PMP treated with CRS and HIPEC. The NLR is a reliable tool that may have a role in predicting outcomes following CRS and HIPEC for patients with PMP of appendiceal origin.