Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1000 patients with perforated appendiceal epithelial tumours

Cisplatin + docetaxel improves survival over cisplatin + mitomycin C in hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei: a retrospective study based on propensity score matching

OBJECTIVE

Pseudomyxoma peritoneum (PMP) of appendiceal origin poses significant treatment challenges with hyperthermic intraperitoneal chemotherapy (HIPEC) regimens offering viable outcomes. This study aimed to compare the efficacy and safety profiles of two HIPEC regimens: cisplatin + docetaxel (CD) and cisplatin + mitomycin C (CM).

METHODS

PMP patients who underwent cytoreductive surgery (CRS) and HIPEC between January 2008 and December 2023 at our center were retrospectively analyzed. Patients were divided into CD and CM groups and matched for baseline characteristics using propensity score matching (PSM). Clinicopathological data, efficacy, and safety profiles were compared. Univariate and multivariate analyses identified independent prognostic factors, and subgroup analyses further compared the two regimens.

RESULTS

After PSM, 104 patients met the inclusion criteria (52 in each group). The median overall survival (mOS) was significantly longer in the CD group (156.3 vs. 60.9 months, p = 0.018), with no significant differences in adverse event severity between groups. Multivariate analysis identified HIPEC regimen, completeness of cytoreduction (CC), and pathological type as independent prognostic factors. Subgroup analysis showed significant mOS benefit for the CD regimen in patients with peritoneal carcinomatosis index (PCI) ≥ 27, CC 2/3, high grade pathology, tumor markers ≥1 evaluated and BMI < 25 (all p < 0.005).

CONCLUSIONS

Following CRS, the CD regimen offers superior survival benefits compared to the CM regimen for PMP patients. These findings highlight the potential of personalized HIPEC strategies to optimize outcomes for PMP treatment.

Selective Gastrectomy with Knowledge of Gastric Anatomy and Blood Supply are Key to Complete Tumour Removal in Advanced Pseudomyxoma: Single-Centre Experience with 120 Gastrectomies Over 20 Years

BACKGROUND

The role of gastrectomy to achieve complete cytoreduction (CCR) for pseudomyxoma peritonei (PMP) is controversial due to uncertain risk/benefit ratio. The outcomes of patients who gastrectomy over a twenty-year period in a high-volume unit are reported.

METHODS

All patients requiring gastrectomy to achieve CCR for appendiceal PMP between 2000 and 2020 were reviewed. Demographics, disease, operative, complication, and survival data were analysed. The first and second decades were compared.

RESULTS

A total of 2148 patients underwent CRS and HIPEC, of which 78% had CCR. Gastrectomy was performed in 7.1%. Median age was 55 years, and 52% were female. Among gastrectomy patients, 94.2% had ≥1 elevated tumour marker, and 18% had high-grade disease. Median PCI was 30, and 30% required subtotal colectomy. Clavien-Dindo III-IV complications occurred in 32%, and 90-day mortality was 1.75%. Median survival was 104 months, and 10-year OS was 47%. Comparing the two decades, total CRS cases almost tripled, with a greater proportion achieving CCR (82.2% vs. 67.8%) but fewer requiring gastrectomy (5.3% vs. 13.5%). In those who had gastrectomy, disease was more advanced (higher PCI, more high-grade disease, more colectomies) in the later period. However, on multivariable analysis, there was no difference in survival between decades. High-grade histology was the only predictor of survival.

CONCLUSIONS

Gastrectomy can achieve good long-term survival with low mortality and acceptable morbidity and should not deter surgeons from achieving CCR. However, increasing experience shows CCR can be achieved, preserving the stomach in the majority of cases through careful consideration of the anatomy and gastric blood supply.

Repeat Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Using Open and Closed Abdomen Techniques for Colorectal Peritoneal Metastases and Peritoneal Pseudomyxoma Recurrences: Results from Six French Expert Centers

BACKGROUND

Standard treatment for resectable peritoneal metastases (PM) combines cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC); however, the rate of recurrence remains high and repeat CRS/HIPEC may be considered in well-selected patients. We describe our postoperative and oncological outcomes.

METHODS

Between 1994 and 2024, data from 132 repeat CRS/HIPEC procedures were analyzed in this retrospective multicenter study. Morbimortality, overall survival (OS) and recurrence-free survival (RFS) were evaluated for colorectal peritoneal metastases (CRPM) and peritoneal pseudomyxoma (PMP).

RESULTS

Overall, 63 patients, including 55 patients with CRPM (87.3%) and 8 patients with PMP (12.7%), underwent CRS/HIPEC. Of these patients, 58 (92%) underwent CRS/HIPEC twice, 4 (6.3%) underwent CRS/HIPEC three times, and 1 (1.6%) underwent CRS/HIPEC four times. Peritoneal Carcinomatosis Index (PCI) score, operating room occupancy, complication and readmission rates at day 90, and length of intensive care unit and hospital stay were similar between the initial and first repeat CRS/HIPEC procedures. No 90-day postoperative mortality occurred. For CRPM, the median OS was 82.3, 53.9, and 74.5 months from the initial, first, and second repeat CRS/HIPEC procedures, respectively, with a median RFS of 22.0, 36.9, and 13.2 months, respectively. For PMP, after a median follow-up of 70.8 and 39.3 months from the initial and first repeat CRS/HIPEC procedures, respectively, all patients were alive, with a median RFS of 22.4 and 39.4 months, respectively. Multivariate analysis shown that no factor was significantly related to severe complications (Dindo-Clavien 3-4) or OS.

CONCLUSIONS

In selected patients with CRPM and PMP, CRS/HIPEC shows comparable results between the initial and repeat procedures in terms of postoperative outcomes, and appears to improve survival, especially for PMP. Repeat CRS/HIPEC is an option to be considered in patients presenting with CRPM or PMP.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: Pseudomyxoma Peritonei

BACKGROUND

The combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) constitutes the established standard of care for pseudomyxoma peritonei patients. However, the role of HIPEC lacks validation through randomized trials, leading to diverse proposed treatment protocols. This consensus seeks to standardize HIPEC regimens and identify research priorities for enhanced clarity.

METHODS

The steering committee applied the patient, intervention, comparator, and outcome method to formulate crucial clinical questions. Evaluation of evidence followed the Grading of Recommendations, Assessment, Development, and Evaluation system. Consensus on HIPEC regimens and research priorities was sought through a two-round Delphi process involving international experts.

RESULTS

Out of 90 eligible panelists, 71 (79%) participated in both Delphi rounds, resulting in a consensus on six out of seven questions related to HIPEC regimens. An overwhelming 84% positive consensus favored combining HIPEC with CRS, while a 70% weak positive consensus supported HIPEC after incomplete CRS. Specific HIPEC regimens also gained consensus, with 53% supporting Oxaliplatin 200 mg/m2 and 51% favoring the combination of cisplatin (CDDP) associated with mitomycin-C (MMC). High-dose MMC regimens received an 89% positive recommendation. In terms of research priorities, 61% of panelists highlighted the importance of studies comparing HIPEC regimens post CRS. The preferred regimens for such studies were the combination of CDDP/MMC and high-dose MMC.

CONCLUSIONS

The consensus recommends the application of HIPEC following CRS based on the available evidence. The combination of CDDP/MMC and high-dose MMC regimens are endorsed for both current clinical practice and future research efforts.

Recurrence and metastasis of pseudomyxoma peritonei: A rare case report

Pseudomyxoma peritonei (PMP) is a relatively uncommon condition primarily associated with neoplasms of the appendiceal epithelium. It is characterized by non-specific clinical manifestations, leading to a high rate of misdiagnosis. This report describes the case of a 62-year-old male patient with recurrent and metastatic PMP. The patient first experienced unexplained epigastric pain and paroxysmal abdominal pain accompanied by distension over 8 years ago. He underwent surgical interventions for the condition in other hospitals in 2015 and 2018, respectively.

What is the optimum post treatment surveillance imaging protocol for low-grade appendiceal mucinous neoplasms and pseudomyxoma peritoneii?

Appendiceal mucinous neoplasms are rare and can be associated with the development of disseminated peritoneal disease known as pseudomyxoma peritonei (PMP). Mucinous tumours identified on appendicectomy are therefore followed up to assess for recurrence and the development of PMP. In addition, individuals who initially present with PMP and are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) are followed up to assess for recurrence. However, despite the concerted efforts of multiple expert groups, the optimal imaging follow-up protocol is yet to be established. The purpose of this article is to review the available evidence for imaging surveillance in these populations to identify the optimum post-resection imaging follow-up protocol.

Long-term outcomes and survival analysis of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy in patients with pseudomyxoma peritonei at a newly established peritoneal malignancy centre in Japan

Background

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is established in the management of pseudomyxoma peritonei (PMP), selected cases of peritoneal mesothelioma, and resectable colorectal or ovarian peritoneal metastases in Western countries. However, the efficacy and feasibility of these techniques are not well established in the Asian population, and little has been reported on long-term survival outcomes for surgically resected PMP patients.

Materials and Methods

Retrospective analysis of a prospective database of short- and longer-term outcomes of consecutive patients who underwent CRS and HIPEC for PMP in a newly established peritoneal malignancy unit in Japan between 2010 and 2016.

Results

A total of 105 patients underwent CRS and HIPEC and 57 maximal tumor debulking (MTD) for pseudomyxoma peritonei. In the CRS group, the primary tumor was appendiceal in 94 patients (90%) followed by ovarian and colorectal. Major postoperative complications occurred in 22/105 patients (21%) with one in-hospital mortality (0.9%). The 5-year overall and disease-free survival rates for the CRS group were 74.2% and 50.1%, respectively. Multivariate analysis revealed unfavorable histology to be the significant predictor of reduced overall and disease-free survival. Completeness of cytoreduction, CA19-9, and CA125 were also associated with disease-free survival.

Conclusions

This is the first report on long-term outcomes and survival analysis of CRS and HIPEC for PMP in the Asian population. CRS and HIPEC can be conducted with reasonable safety and favorable survival in a new center. Complete tumor removal and histological type are the strongest prognostic factors for both overall and disease-free survival.

Analysis of causes and prognostic impact of tube occlusion during hyperthermic intraperitoneal chemotherapy for appendiceal pseudomyxoma peritonei

BACKGROUND

Appendiceal pseudomyxoma peritonei (PMP), a rare tumor from mucinous appendiceal origins, is treated with Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC). However, tubing blockages during HIPEC treatment pose a common challenge, impeding the smooth progression of therapy. Few studies to date have explored the incidence and risk factors of tube occlusion during HIPEC in patients with appendiceal PMP, as well as its adverse impact on postoperative complications.

METHODS

From October 2017 to June 2023, a total of 80 patients with appendiceal PMP undergoing combined CRS and HIPEC were included in this study. Tubing blockage events were strictly defined, with patients experiencing blockages during HIPEC treatment allocated to the study group, while those with unobstructed perfusion were assigned to the control group. A comparative analysis was conducted between the two groups regarding post-HIPEC health assessments and occurrence of complications. Risk factors for luminal occlusion during closed HIPEC procedures were identified through univariate and multivariate analysis of data from 303 HIPEC treatments.

RESULTS

Tubing blockages occurred in 41 patients (51.3%). The study group experienced prolonged gastrointestinal decompression time (4.1 ± 3.0 vs. 2.5 ± 1.7 days, P = 0.003) and prolonged time to bowel movement (6.1 ± 2.3 vs. 5.1 ± 1.8 days, P = 0.022) compared to the control group. There was no significant difference in the incidence of complications between the two groups. The 1-year survival rate postoperatively was 97%, and the 3-year survival rate was 81%, with no association found between tubing blockage and poorer survival. Additionally, In 303 instances of HIPEC treatment among these 80 patients, tube occlusion occurred in 89 cases (89/303, 29.4%). Multivariable logistic regression analysis revealed age, diabetes, hypertension, and pathology as independent risk factors for tube occlusion.

CONCLUSION

Tubing blockages are a common occurrence during HIPEC treatment, leading to prolonged postoperative gastrointestinal functional recovery time. When patients are elderly and have concomitant hypertension and diabetes, along with a histological type of low-grade mucinous tumor, the risk of tube occlusion increases. However, this study did not find a significant correlation between tubing blockage and the incidence of postoperative complications or overall patient survival.

Peritoneal malignancy in the global COVID-19 pandemic: experience of recovery and restoration in a high-volume centre through NHS and independent sector collaboration

INTRODUCTION

Treatment of peritoneal malignancy with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) requires substantial critical care, theatre and nursing resources. The COVID-19 pandemic caused challenges in providing a high volume, tertiary referral service.

METHODS

We reviewed data on referrals and operations performed in a tertiary referral centre in both NHS and independent sector settings. The impact of COVID-19 on activity was assessed using 2019 as a benchmark.

RESULTS

New patient referrals were similar, with 891 in 2019 compared with 833 in 2020. Delivery of CRS and HIPEC operations were initially impacted by COVID-19. NHS and independent sector collaboration facilitated recovery, with 284 patients treated in 2020 compared with 280 in 2019.

CONCLUSIONS

Close collaboration and structural organisation between the clinical and management teams in the NHS and independent sectors facilitated recovery and restoration of a complex tertiary referral service for peritoneal malignancy during the COVID pandemic.

Complexity of surgery and treatment burden in patients with peritoneal malignancy is not determined by addition of hyperthermic intraperitoneal chemotherapy

BACKGROUND

This study describes surgical and quality of life outcomes in patients with peritoneal malignancy treated by cytoreductive surgery (CRS) alone compared with a subgroup treated with CRS and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

Peritoneal malignancy patients undergoing surgery between 2017 and 2023 were included. The cohort was divided into patients treated by CRS and HIPEC and those treated by CRS without HIPEC (including CRS only or maximal tumour debulking (MTB)). Main outcomes included surgical outcomes, survival, and quality of life. Groups were compared using non-parametric tests and log-rank test was used to compare survival curves.

RESULTS

403 had CRS and HIPEC, 25 CRS only and 15 MTB. CRS and HIPEC patients had a lower peritoneal carcinomatosis index (12.0 vs. 17.0 vs. 35.0; P < 0.001) and longer surgical operative time (9.3 vs. 8.3 vs. 5.2 h; P < 0.001), when compared to CRS only and MTB, respectively. No other significant difference between groups was observed.

CONCLUSIONS

The optimal management of selected patients with resectable peritoneal malignancy incorporates a combined strategy of CRS and HIPEC. When HIPEC is not utilized, due to significant residual disease or comorbidity precluding safe delivery, CRS alone is associated with good outcomes. Hospital stay and complications are acceptable but not significantly different to the CRS and HIPEC group. CRS alone is a complex intervention requiring comparable resources with good outcomes. In view of our findings 'intention to treat' with CRS and HIPEC should be the basis for resource allocation and funding.

Long-term survival following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in Waikato, Aotearoa New Zealand: a 12-year experience

BACKGROUNDS

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have improved survival for selected cases of peritoneal surface malignancy. In 2008, a CRS/HIPEC service was first established in Aotearoa New Zealand (AoNZ) at Waikato and Braemar Hospitals in the Waikato region.

METHODS

This is a retrospective review of a prospectively maintained database of all patients undergoing CRS/HIPEC from 1 January 2008 to 1 November 2020 at Waikato and Braemar Hospitals. We analysed long-term survival and predictors of survival for each tumour type.

RESULTS

240 procedures were performed for 221 patients, including 22 re-do procedures. Cases had a median peritoneal cancer index of 16. Complete cytoreduction (CC0-1) was achieved in 196 cases (81.7%). All complete cytoreduction cases received HIPEC. There were 152 pseudomyxoma peritonei (PMP), 39 colorectal cancers (CRC), 29 appendiceal cancers, eight ovarian cancers, six peritoneal mesotheliomas, and six other cancers. The 5-year overall survival (OS) for PMP with acellular mucin, low-grade mucinous carcinoma peritonei, and high-grade mucinous carcinoma peritonei with or without signet cells were 91.6%, 80.5%, and 72.2%, respectively. 2- and 5-year OS in CRC were 56.7% and 40.4%. The achievement of complete cytoreduction improved the 5-year OS to 87.9% across all PMP and 45.1% in colorectal cancer. Incomplete cytoreduction predicted worse survival in appendiceal PMP. In colorectal cancer, worse survival was predicted in those who had incomplete cytoreduction, liver metastasis, and presentation with obstruction and perforation.

CONCLUSION

Favourable long-term outcomes following CRS/HIPEC for peritoneal surface malignancy have been achieved in AoNZ through the Waikato peritonectomy service.

Appendicitis to multivisceral transplantation: a career experience with appendiceal malignancy

John Hunter is regarded as the father of scientific surgery. His principles involved reasoning, observation and experimentation. His most powerful saying was: "Why not try the experiment?" This manuscript charts a career in abdominal surgery ranging from the treatment of appendicitis to the development of the largest appendiceal tumour centre in the world. The journey has led to the first report of a successful multivisceral and abdominal wall transplant for patients with recurrent non-resectable pseudomyxoma peritonei. We all stand on the shoulders of giants and surgery progresses by learning from the past while being prepared to experiment into the future.

Global trends in research of pseudomyxoma peritonei: a bibliometric and visualization analysis

Objective

Pseudomyxoma peritonei (PMP) was a complex disease that had attracted increasing attention. However, there had been no bibliometric analysis of this disease so far. This study aimed to explore the current situation and frontier trend of PMP through bibliometric and visualization analysis, and to indicate new directions for future research.

Methods

The original research articles and reviews related to the PMP research were downloaded from Web of Science Core Collection on September 11, 2023. CiteSpace (6.2.R4) and VOSviewer(1.6.18) were used to perform bibliometric analysis of the publications, and establish the knowledge map. The data collected was analyzed using the Online Analysis Platform of Bibliometric to evaluate the cooperation of countries in this field.

Results

We identified 1449 original articles and reviews on PMP published between 1998 and 2023. The number of publications on PMP increased continuously. The United States, the United Kingdom and China were the top contributors. The most productive organization was the MedStar Washington Hospital Center. Sugarbaker, Paul H. was the most prolific author and the most cited. Keyword analysis showed that "Pseudomyxoma peritonei", "cancer", "cytoreductive surgery", and "hyperthermic intraperitoneal chemotherapy" were the most common keywords. The earliest and latest used keywords were "mucinous tumors" and "impact", respectively. "classification", "cytoreductive surgery", "appendiceal" were the top 3 strongest citation bursts. The reference "Carr NJ, 2016, AM J SURG PATHOL" had the highest co-citations.

Conclusion

This bibliometric analysis showed an increasing trend in literature related to PMP. The research trends and hotspots identified in this study could guide the future research directions in this field, in order to promote the development of PMP.

A case of pseudomyxoma peritonei arising from a perforated intraductal papillary mucinous neoplasm that underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Pseudomyxoma peritonei (PMP) of pancreatic origin arising from an intraductal papillary mucinous neoplasm (IPMN) is rare. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has been established as the optimal treatment for PMP. However, the benefits and safety of CRS with HIPEC for treating PMP of pancreatic origin remain unclear. Herein, we describe a case of PMP of pancreatic origin that was treated with CRS and HIPEC without postoperative complications. A 75-year-old woman was referred to our department. Computed tomography (CT) revealed a multilocular cystic tumor in the pancreatic tail, notable mucinous ascites in the abdominal cavity, and scalloping of the liver and spleen. CT did not reveal the appendix, and the ovaries were normal in size. The patient was diagnosed with PMP of pancreatic origin, and CRS and HIPEC were performed. Intraoperatively, the pancreatic tumor was perforated, and there was a large amount of mucinous ascites. We performed distal pancreatectomy in addition to CRS and HIPEC, with no intraoperative complications. The postoperative course was uneventful, and the patient survived after 6 months without recurrence. CRS with HIPEC may be a feasible treatment option for PMP of pancreatic origin.

Genome-Wide Analysis of DNA Methylation in Pseudomyxoma Peritonei Originated from Appendiceal Neoplasms

INTRODUCTION

Pseudomyxoma peritonei (PMP) is a disease characterized by progressive accumulation of intraperitoneal mucinous ascites produced by neoplasms in the abdominal cavity. Since the prognosis of patients with PMP remains unsatisfactory, the development of effective therapeutic drug(s) is a matter of pressing concern. Genetic analyses of PMP have clarified the frequent activation of GNAS and/or KRAS. However, the involvement of global epigenetic alterations in PMPs has not been reported.

METHODS

To clarify the genetic background of the 15 PMP tumors, we performed genetic analysis using AmpliSeq Cancer HotSpot Panel v2. We further investigated global DNA methylation in the 15 tumors and eight noncancerous colonic epithelial tissues using MethylationEPIC array BeadChip (Infinium 850k) containing a total of 865,918 probes.

RESULTS

This is the first report of comprehensive DNA methylation profiles of PMPs in the world. We clarified that the 15 PMPs could be classified into at least two epigenotypes, unique methylation epigenotype (UME) and normal-like methylation epigenotype (NLME), and that genes associated with neuronal development and synaptic signaling may be involved in the development of PMPs. In addition, we identified a set of hypermethylation marker genes such as HOXD1 and TSPYL5 in the 15 PMPs.

CONCLUSIONS

These findings may help the understanding of the molecular mechanism(s) of PMP and contribute to the development of therapeutic strategies for this life-threatening disease.

Hyperthermic intraperitoneal chemotherapy in patients with incomplete cytoreduction for appendiceal pseudomyxoma peritonei: a 10-year treatment experience in China

BACKGROUND

To explore the application value of hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with incomplete cytoreduction for appendiceal pseudomyxoma peritonei (PMP).

METHODS

We retrospectively analyzed the clinical data of 526 patients with incomplete cytoreduction for appendiceal PMP to discover its prognostic factors, and the therapeutic value of HIPEC.

RESULTS

The 5-year and 10-year overall survival rates of patients after cytoreductive surgery (CRS) treated with HIPEC were significantly higher than those without HIPEC (5y-OS: 58% vs. 48%, 10y-OS: 37% vs. 16%, P = 0.032). The median progression-free survival (PFS) following CRS was 20 months, with a 20% 3-year PFS. The median PFS following CRS + HIPEC was 33 months, with a 60% 3-year PFS (P = 0.000). Univariate analysis indicated that HIPEC, gender, completeness of cytoreduction (CCR) and pathological grade had statistical difference. Multivariate analysis showed that CRS without HIPEC and high pathological grade were independent risk factors for poor prognosis and rapid tumor progression.

CONCLUSIONS

HIPEC may prolong the survival in patients with incomplete cytoreduction for low-grade appendiceal PMP. High pathological grade indicates poor survival and rapid tumor progression.

Occult appendix pathology in patients undergoing colorectal cancer resection and prophylactic appendectomy

BACKGROUND

The risk-benefit balance of prophylactic appendectomy in patients undergoing left colorectal cancer resection is unclear. The aim of this report is to assess the proportion of histologically abnormal appendices in patients undergoing colorectal cancer resection in a unit where standard of care is appendectomy, with consent, when left-sided resection is performed.

METHODS

A retrospective study on a prospectively collected database was conducted in a single tertiary-care center. Overall, 717 consecutive patients undergoing colorectal cancer resection between January 2015 and June 2021 were analyzed. The primary outcome was the proportion of histologically abnormal appendix specimens at prophylactic appendectomy. The secondary outcome was complications from prophylactic appendectomy.

RESULTS

Overall, 576/717 (80%) patients had appendectomy at colorectal cancer surgery. In total, 234/576 (41%) had a right-/extended-right hemicolectomy or subtotal colectomy which incorporates appendectomy, and 342/576 (59%) had left-sided resection (left-hemicolectomy, anterior resection or abdominoperineal excision) with prophylactic appendectomy. At definitive histology, 534/576 (92.7%) had a normal appendix. The remaining 42/576 (7.3%) showed abnormal findings, including: 14/576 (2.4%) inflammatory appendix pathology, 2/576 (0.3%) endometriosis, 8/576 (1.4%) hyperplastic polyp, and 18/576 (3.1%) appendix tumors, which encompassed six low-grade appendiceal mucinous neoplasms (LAMNs), three carcinoids, and nine serrated polyps. In the 342 patients who had prophylactic appendectomy, 10 (2.9%) had a neoplasm (two LAMN, three carcinoids, and five serrated polyps). There were no complications attributable to appendectomy.

CONCLUSION

Occult appendix pathology in patients undergoing colorectal cancer resection is uncommon when prophylactic appendectomy was performed. However, approximately 3% of patients had a synchronous appendix neoplasm.

Analysis of the characteristics and outcomes of patients with pseudomyxoma peritonei of appendiceal origin treated with curative-intent surgery

BACKGROUND

There are no previous studies on pseudomyxoma peritonei regarding the details of surgical procedures included in cytoreductive surgery and quantitative evaluation for peritoneal metastases by region in the abdominal cavity. This study aimed to describe the characteristics and procedural details involved in cytoreductive surgery, and survival outcomes of patients with pseudomyxoma peritonei originating from appendiceal mucinous neoplasm, and identify differences in the difficulty of cytoreductive surgery based on tumor location.

METHODS

Patient characteristics and survival outcomes were studied through a retrospective review. The complete cytoreduction rate (i), the 5-year survival rate for patients with complete cytoreduction (ii), and an index as a complement (i × ii × 100) were described for patients who had tumors larger than 50 mm in one of the 13 regions of the abdominal cavity.

RESULTS

A total of 989 patients were treated with curative-intent cytoreductive surgery. The median peritoneal cancer index was 18 (interquartile range, 6-29), with complete cytoreduction achieved in 702 patients (71%); the major complication rate was 17%. The median overall survival was 92.9 months, compared to 53.8 months for patients who underwent total gastrectomy and 30.4 months for those who underwent total colectomy. In the 13 abdominal regions, the index scores indicating cytoreduction difficulty were categorized into three risk groups: upper and mid-abdominal (>20), lateral abdominal (10-20), and small bowel (<10).

CONCLUSIONS

Cytoreductive surgery offered favorable survival outcomes, even in cases involving total gastrectomy. The difficulty of achieving complete cytoreduction varied across abdominal regions and was classified into three levels.

Health related quality of life is excellent and sustained at two decades after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in survivors of pseudomyxoma peritonei of appendiceal origin

INTRODUCTION

Optimal management of pseudomyxoma peritonei (PMP) is by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), which can achieve 20-year disease-free, and overall survival. There is limited information on the health-related quality of life (HRQOL) of PMP survivors beyond five years. We report longitudinal HRQOL in patients with PMP of appendiceal origin up to 17-years after their CRS and HIPEC in 2003-2004.

METHODS

Patients had HRQOL assessed with EORTC QLQ-C30 questionnaires pre-operatively, and at 1-, 10- and 17-years post-operatively. Comparisons in global health-related QOL (global-HRQOL) measures were made with (1) an age- and sex-matched normal European population, (2) between patients who underwent complete cytoreduction (CRS CC0/1) versus maximal tumor debulking (MTD), and (3) between those with and without peritoneal recurrence.

RESULTS

Forty-six patients underwent CRS & HIPEC for appendiceal PMP. One patient withdrew from the study. Of the 45 patients, 23 patients were alive at ten and 15 patients at 17-years post-operatively. 21/23 (91%) and 14/15 patients (93%) completed questionnaires respectively. Pre-operatively, patients had significantly lower global-HRQOL compared with the reference population. Over follow-up, patients experienced improvements in their global-HRQOL. By post-operative year-10 and -17, there was no difference between the global-HRQOL of patients and reference population. As expected, patients with CC0/1 and without peritoneal tumor recurrence had better global-HRQOL at ten- and 17-years post-operatively compared with those with MTD or recurrence.

CONCLUSIONS

Optimal CRS and HIPEC is an effective treatment for appendiceal PMP that can achieve long-term survival. HRQOL is excellent and maintained, in those who have CC0/1 without recurrence.

Long-term survival in patients with PMP: a single-institutional retrospective study from China

BACKGROUND

As the standard treatment for pseudomyxoma peritonei (PMP), cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) can significantly prolong the survival of PMP patients, and some patients can even achieve long-term survival (LTS) or clinical cure. The purpose of this study was to analyze the clinicopathological and treatment features of PMP patients with LTS and to explore the survival benefit factors of PMP patients.

METHODS

The clinicopathological and prognostic data of PMP patients who received CRS + HIPEC at our center from December 2004 to May 2023 were retrospectively analyzed. PMP patients were divided into LTS group (≥ 10 years) and short-term survival (STS) group (< 5 years) according to the length of natural history. Univariate and multivariate analyses were performed to explore the beneficial factors of PMP patients with LTS.

RESULTS

A total of 609 patients with PMP received CRS + HIPEC treatment at our center. Two-hundred one patients with PMP were included in the study after screening, including 39 patients (19.4%) in the LTS group and 162 patients (80.6%) in the STS group. In STS group and LTS group, median overall survival based on natural history was 29.2 (2.4-59.9) vs. 138.9 (120.3-416.7) months. Univariate analysis revealed 8 factors (P < 0.05) with statistically significant differences between the two groups: gender, chemotherapy history, previous surgical score, Karnofsky Performance Status score, pathological diagnosis, lymphatic metastasis, peritoneal cancer index, and completeness of cytoreduction (CC). Multivariate analysis identified only two factors independently associated with LTS of PMP patients: CC and pathological diagnosis.

CONCLUSION

Complete CRS and pathological features are two key factors affecting LTS in PMP 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.

[Surgical treatment for recurrent intra-abdominal mucinous neoplasms]

BACKGROUND

The gold standard in the treatment of mucinous intra-abdominal neoplasms is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Despite complete cytoreduction up to 45% of patients develop recurrences.

METHOD

A search and analysis of the current literature were carried out.

RESULTS

There is still controversy regarding the best treatment strategy for patients with recurrent pseudomyxoma peritonei (PMP) after CRS and HIPEC. The clinical management of these patients depends on many factors, such as the site and volume of recurrence, histological subtype and symptoms. Treatment options range from repeated surgery with curative intent with or without HIPEC to watch and wait strategies. In selected patients redo surgery is feasible and safe with low morbidity and mortality. Iterative complete CRS can result in a median 5‑year overall survival of more than 80%. Debulking surgery leads to a prolonged survival and to symptom control fora period with of nearly 2 years.

CONCLUSION

Repeated complete cytoreduction of recurrent PMP can result in long-term survival. Tumor debulking surgery may be particularly beneficial for symptomatic patients.

[Surgical treatment of pseudomyxoma peritonei-Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy]

BACKGROUND

Pseudomyxoma peritonei syndrome (PMP) is an orphan disease. Surgery is the fundament of treatment.

METHOD

Short review summarizing the state of the art treatment.

RESULTS

Cytoreductive surgery (CRS) in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) form the foundations of treatment for PMP. The peritoneal cancer index should be preoperatively determined based on imaging and/or laparoscopy, intraoperatively validated and both should be documented. An extraperitoneal surgical preparation technique leads to effective en bloc resection of the peritoneum and the affected abdominal area. The HIPEC technique should be performed with mitomycin C for 60-90 min. Complete CRS (CC = 0, CC = 1) and the histological subtype are relevant for the prognosis. Structured educational programs and mentoring can optimize the learning curve. The aftercare should be performed at the surgical center. After follow-up imaging at 3 months after CRS, in the first 2 years a control should be carried out every 6 months. Thereafter, the intervals can be extended to 1 year.

CONCLUSION

Standardized surgical treatment and HIPEC, optimized specific surgical training and structured follow-up at the center lead to an excellent long-term prognosis for patients with PMP.

Etiological analysis of infection after CRS + HIPEC in patients with PMP

BACKGROUND

Cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) is the standard treatment for pseudomyxoma peritonei (PMP). It can significantly prolong the survival of patients, but at the same time may increase the risk of postoperative infection.

METHOD

Patients with PMP who underwent CRS + HIPEC at our center were retrospectively analyzed. According to PMP patients, basic clinical data and relevant information of postoperative infection, we analyzed the common sites of postoperative infection, results of microbial culture and the antibiotics sensitivity. Univariate and multivariate analysis were performed to explore infection-related risk factors.

RESULT

Among the 482 patients with PMP, 82 (17.0%) patients were infected after CRS + HIPEC. The most common postoperative infection was central venous catheter (CVC) infection (8.1%), followed by abdominal-pelvic infection (5.2%). There were 29 kinds of microbes isolated from the culture (the most common was Staphylococcus epidermidis), including 13 kinds of Gram-positive bacteria, 12 kinds of Gram-negative bacteria, and 4 kinds of funguses. All the antibiotics sensitivity results showed that the most sensitive antibiotics were vancomycin to Gram-positive bacteria (98.4%), levofloxacin to Gram-negative bacteria (68.5%), and fluconazole to fungus (83.3%). Univariate and multivariate analysis revealed the infection independent risk factors as follow: intraoperative blood loss ≥ 350 mL (P = 0.019), ascites volume ≥ 300 mL (P = 0.008).

CONCLUSION

PMP patients may have increased infection risk after CRS + HIPEC, especially CVC, abdominal-pelvic and pulmonary infections. The microbial spectrum and antibiotics sensitivity results could help clinicians to take prompt prophylactic and therapeutic approaches against postoperative infection for PMP patients.

Intraperitoneal BromAc® Does Not Interfere with the Healing of Colon Anastomosis

A combination of bromelain and acetylcysteine, BromAc®, is an efficient intraperitoneal mucolytic for thick mucus secreted in pseudomyxoma peritonei (PMP). Patients with PMP quite often undergo colon anastomosis. Hence, we investigated the effect of the intraperitoneal delivery of BromAc® on colon-anastomosis healing in a rat model. Sixteen Wistar rats were divided into two groups (N = 8). The controls received intraperitoneal saline after anastomosis, whilst the other group received BromAc®. They were monitored for body-weight and general health parameters. Half the rats in each group (N = 4) were culled at 4 or 13 days post-surgery for assessment. The healing process of the tissues was assessed by burst pressure and collagen density with histology to assess the integrity of the internal organs. The results indicated that there was a similar pattern of weight fluctuation during the experiment, although the rats treated with the BromAc® showed slightly greater weight loss during the first 4 days. Although the burst pressure was similar in both groups, the BromAc® group at day 13 showed a slightly higher burst pressure, which was complemented by a higher collagen density (albeit not statistically significant). The histology of the internal organs was comparable to those of the controls. This study indicates that the intraperitoneal delivery of BromAc® in a rat model does not interfere with the healing process of colonic anastomosis.

Overall survival and morbidity are not associated with advanced age for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: a single centre experience

Objectives

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has enabled better prognosis for patients with peritoneal surface malignancies. However, in older age groups, short -and long-term outcomes are still perceived as poor. We evaluated patients aged 70 and over and determine if age is a predictor of morbidity, mortality and overall survival (OS).

Methods

A retrospective cohort analysis was performed on CRS/HIPEC patients and categorised by age. The primary outcome was overall survival. Secondary outcomes included morbidity, mortality, hospital and incentive care unit (ICU) stay and early postoperative intraperitoneal chemotherapy (EPIC).

Results

A total of 1,129 patients were identified with 134 aged 70+ and 935 under 70. There was no difference in OS (p=0.175) or major morbidity (p=0.051). Advanced age was associated with higher mortality (4.48 vs. 1.11 %, p=0.010), longer ICU stay (p<0.001) and longer hospitalisation (p<0.001). The older group was less likely to achieve complete cytoreduction (61.2 vs. 73 %, p=0.004) and receive EPIC (23.9 vs. 32.7 %, p=0.040).

Conclusions

In patients undergoing CRS/HIPEC, age of 70 and above does not impact OS or major morbidity but is associated with increased mortality. Age alone should not be a limiting factor in selecting CRS/HIPEC patients. Careful multi-disciplinary approach is needed when considering those of advanced age.

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.

Determining a minimum data set for reporting clinical and radiologic data for pseudomyxoma peritonei

Objectives

Pseudomyxoma peritonei (PMP) is a rare cancer currently affecting over 11,736 patients across Europe. Since PMP is so uncommon, collaboration between scientific centers is key to discovering the mechanisms behind the disease, efficient treatments, and targets pointing to a cure. To date, no consensus has been reached on the minimum data that should be collected during PMP research studies. This issue has become more important as biobanking becomes the norm. This paper begins the discussion around a minimum data set that should be collected by researchers through a review of available clinical trial reports in order to facilitate collaborative efforts within the PMP research community.

Content

A review of articles from PubMed, CenterWatch, ClinicalTrials.gov and MedRxiv was undertaken, and clinical trials reporting PMP results selected.

Summary

There is a core set of data that researchers report, including age and sex, overall survival, peritoneal cancer index (PCI) score, and completeness of cytoreduction, but after this, reports become variable.

Outlook

Since PMP is a rare disease, it is important that reports include as large of a number of standardised data points as possible. Our research indicates that there is still much ground to cover before this becomes a reality.

Elevated temperatures and longer durations improve the efficacy of oxaliplatin- and mitomycin C-based hyperthermic intraperitoneal chemotherapy in a confirmed rat model for peritoneal metastasis of colorectal cancer origin

Introduction

In patients with limited peritoneal metastasis (PM) originating from colorectal cancer, cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is a potentially curative treatment option. This combined treatment modality using HIPEC with mitomycin C (MMC) for 90 minutes proved to be superior to systemic chemotherapy alone, but no benefit of adding HIPEC to CRS alone was shown using oxaliplatin-based HIPEC during 30 minutes. We investigated the impact of treatment temperature and duration as relevant HIPEC parameters for these two chemotherapeutic agents in representative preclinical models. The temperature- and duration- dependent efficacy for both oxaliplatin and MMC was evaluated in an in vitro setting and in a representative animal model.

Methods

In 130 WAG/Rij rats, PM were established through i.p. injections of rat CC-531 colon carcinoma cells with a signature similar to the dominant treatment-resistant CMS4 type human colorectal PM. Tumor growth was monitored twice per week using ultrasound, and HIPEC was applied when most tumors were 4-6 mm. A semi-open four-inflow HIPEC setup was used to circulate oxaliplatin or MMC through the peritoneum for 30, 60 or 90 minutes with inflow temperatures of 38°C or 42°C to achieve temperatures in the peritoneum of 37°C or 41°C. Tumors, healthy tissue and blood were collected directly or 48 hours after treatment to assess the platinum uptake, level of apoptosis and proliferation and to determine the healthy tissue toxicity.

Results

In vitro results show a temperature- and duration- dependent efficacy for both oxaliplatin and MMC in both CC-531 cells and organoids. Temperature distribution throughout the peritoneum of the rats was stable with normothermic and hyperthermic average temperatures in the peritoneum ranging from 36.95-37.63°C and 40.51-41.37°C, respectively. Treatments resulted in minimal body weight decrease (&lt;10%) and only 7/130 rats did not reach the endpoint of 48 hours after treatment.

Conclusions

Both elevated temperatures and longer treatment duration resulted in a higher platinum uptake, significantly increased apoptosis and lower proliferation in PM tumor lesions, without enhanced normal tissue toxicity. Our results demonstrated that oxaliplatin- and MMC-based HIPEC procedures are both temperature- and duration-dependent in an in vivo tumor model.

Secondary cytoreductive surgery for 86 patients with mucinous appendiceal adenocarcinoma

BACKGROUND

After patients have a surgical procedure for a gastrointestinal cancer, follow-up is indicated. If cancer progression is documented in patients with mucinous appendiceal adenocarcinoma (MACA), a secondary cytoreductive surgery (SCRS) may be considered.

METHODS

In patients who had a prior complete cytoreductive surgery (CRS), variables associated with the index CRS and SCRS were extracted. These variables were statistically assessed for their impact on survival.

RESULTS

Of 198 MACA patients, 86 (43.4%) had SCRS. The median follow-up was 5.0 years and the median survival was 7 years. Significant prognostic variables associated with the index CRS by univariant analysis was histopathologic grade of MACA-Intermediate (MACA-Int) as compared to other MACA histologic subtypes (p = 0.0164). Significant prognostic variables associated with the SCRS were bowel obstruction (p = 0.0149), interval of CRS to SCRS (p = 0.0059), and completeness of cytoreduction (p = 0.0014).

CONCLUSIONS

In the analysis of variables from SCRS, the interval from CRS to SCRS ≤24 months indicates an aggressive biology of the disease. The CC score of complete versus incomplete decreased median survival from 11 to 4 years. A composite of these two variables allowed prediction of survival of 50% when patients showed these two favorable variables and only 9.1% when these variables were unfavorable.

Staging of appendiceal mucinous neoplasms: challenges and recent updates

Low-grade appendiceal mucinous neoplasms are unique tumors of the appendix, characterized by low-grade mucinous epithelium with villiform, undulating, or flat architecture. These tumors lack infiltrative growth or destructive invasion, but can extend into the appendiceal wall by a "pushing" pattern of invasion, with a broad front that can mimic a diverticulum. These neoplasms have a propensity for peritoneal dissemination, resulting in the clinical presentation of pseudomyxoma peritonei. The pathologic staging of these neoplasms is challenging and fraught with confusing terminology and numerous classification systems. This review focuses on the AJCC pathologic staging of these tumors with a focus on challenging situations.

Secondary cytoreductive surgery for lymph node positive mucinous appendiceal neoplasms

BACKGROUND

Patients who have surgery for a gastrointestinal cancer routinely have clinical and radiological tests in an effort to detect recurrent disease. If cancer progression is documented, additional surgery performed in a timely manner may prolong survival and help maintain an optimal quality of life. In mucinous appendiceal cancer patients a secondary cytoreductive surgery (SCRS) may be considered if recurrent disease is detected.

METHODS

In patients with both lymph node metastases and peritoneal metastases from a mucinous appendiceal adenocarcinoma (MACA-LN) who had a prior complete cytoreductive surgery (CRS), the clinical- and treatment-related variables associated with the index CRS and the SCRS were extracted from a database and secured research files. These variables were statistically assessed for their impact on survival.

RESULTS

Twelve of 39 lymph node positive patients (30.8%) had SCRS. The mean follow-up was 7.6 years and the median survival was 4.5 years. There were 4 males (33%) and median age was 44 years. Significant prognostic variables associated with improved survival with the index CRS by univariant analysis was the use of early postoperative intraperitoneal chemotherapy (EPIC) (p = 0.0469). For the SCRS, no significant prognostic variables, not even completeness of cytoreduction, were discovered.

CONCLUSIONS

In MACA-LN patients, improved survival with SCRS was shown as compared to patients who recurred but did not undergo SCRS. In this group of patients with an aggressive disease, if SCRS was possible it improved survival with long-term (greater than 5 years) follow-up.

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.

Effect of standardized fluid management on cardiac function after CRS + HIPEC in patients with PMP: a single-center case-control study

OBJECTIVE

To investigate the effects of standardized fluid management (SFM) on cardiac function in patients with pseudomyxoma peritonei (PMP) after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHOD

Patients with PMP who underwent CRS + HIPEC at our center were retrospectively analyzed. The patients were divided into control and study groups according to whether SFM was applied after CRS + HIPEC. We compared the preoperative and postoperative cardiac and renal function parameters, daily fluid volume three days after CRS, and cardiovascular-related adverse events. Univariate and multivariate analyses were performed to identify the indicators affecting clinical prognosis.

RESULT

Among the 104 patients, 42 (40.4%) were in the control group and 62 (59.6%) in the study group. There were no statistically significant differences between the two groups in the main clinicopathological characteristics, preoperative cardiac and renal function parameters, and CRS + HIPEC-related indicators. The incidences of cardiac troponin I (CTNI) > upper limit of normal (ULN), >2 × ULN, >3 × ULN, serum creatinine > ULN, and blood urea nitrogen > ULN were higher in the control group than in the study group (p < 0.05). The median daily fluid volume of the control group was higher than that of the study group 3 days after CRS (p < 0.05). Postoperative CTNI > 2 × ULN was an independent risk factor for serious circulatory adverse events. Survival analysis revealed pathological grading, completeness of cytoreduction score, and postoperative CTNI > ULN as independent prognostic factors.

CONCLUSIONS

SFM after CRS + HIPEC in patients with PMP may reduce cardiovascular adverse events risk and improve clinical outcomes.

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.

[Current treatment recommendations for pseudomyxoma peritonei]

BACKGROUND

The term pseudomyxoma peritonei (PMP) describes a clinical syndrome characterized by the presence of gelatinous intraperitoneal accumulation of mucus. It mostly originates from a mucocele of the vermiform appendix. Affected patients are often asymptomatic for a long time. Because of its indolent nature it is usually diagnosed at an advanced stage. Clinical presentation is determined by the dissemination of the tumor.

METHOD

A search and analysis of the current literature were carried out.

RESULTS

Based on the morphological characteristics PMP subtypes with various malignant potential can be differentiated. The prognosis depends on the histopathological differentiation and the clinical stage. The treatment spectrum varies from laparoscopic appendectomy to complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC).

CONCLUSION

Due to the rarity of PMP there are no prospective randomized studies. Therefore, there is still controversy regarding the best stage-dependent treatment strategy. This review article attempts to clarify the optimal management of mucinous neoplasms of the appendix and PMP taking the clinical presentation and the histological differentiation into consideration.

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

Survival prediction by Bayesian network modeling for pseudomyxoma peritonei after cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy

OBJECTIVES

To establish a survival prognostic model for pseudomyxoma peritonei (PMP) treated with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) based on Bayesian network (BN).

METHODS

453 PMP patients were included from the database at our center. The dataset was divided into a training set to establish BN model and a testing set to perform internal validation at a ratio of 8:2. From the training set, univariate and multivariate analyses were performed to identify independent prognostic factors for BN model construction. The confusion matrix, receiver operating characteristic (ROC) curve and the area under curve (AUC) were used to evaluate the performance of the BN model.

RESULTS

The univariate and multivariate analyses identified 7 independent prognostic factors: gender, previous operation history, histological grading, lymphatic metastasis, peritoneal cancer index, completeness of cytoreduction and splenectomy (all p < 0.05). Based on independent factors, the BN model of training set was established. After internal validation, the accuracy and AUC of the BN model were 70.3% and 73.5%, respectively.

CONCLUSION

The BN model provides a reasonable level of predictive performance for PMP patients undergoing CRS + HIPEC.

Validation of a Nomogram to Predict Recurrence in Patients with Mucinous Neoplasms of the Appendix with Peritoneal Dissemination After Cytoreductive Surgery and HIPEC

BACKGROUND

Survival of patients affected by mucinous appendiceal neoplasms with peritoneal dissemination (PD) is mainly related to histopathological features. However, prognostic stratification is still a concern, as the clinical course of the disease is often unpredictable. The aim of this study is to construct and externally validate a nomogram predicting disease-free survival (DFS) in mucinous appendiceal neoplasms with PD treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

PATIENTS AND METHODS

Patients treated in two referral centers were included: Hospital General Universitario Gregorio Marañón, Madrid, Spain (derivation cohort) and Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy (validation cohort). Cox regression analysis identified factors associated with shorter DFS in the derivation cohort. The nomogram performance was externally evaluated in the validation cohort using concordance index and calibration plots. Histology was classified according to the Peritoneal Surface Oncology Group International (PSOGI).

RESULTS

The derivation cohort included 95 patients, and the validation cohort 348. Five-year DFS rates were 51.5 and 62%, respectively. Cox regression analysis (derivation cohort) identified PSOGI histology of the peritoneal components, number of preoperative elevated tumor marker, and peritoneal disease extent, as assessed by peritoneal carcinomatosis index, to be predictors of DFS. The model's predictive capacity was higher than that of PSOGI classification alone, with respective concordance indexes of 0.702 ± 0.023 and 0.610 ± 0.018 (validation cohort). The nomogram approximated the perfect model in the calibration plots at 3- and 5-year DFS.

CONCLUSIONS

An easy-to-use model that provides better prognostic stratification than histopathological features has been constructed. This nomogram may help clinicians in individualized survival predictions and informed clinical decision-making.

Update of randomized controlled trials evaluating cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in prevention and therapy of peritoneal metastasis: a systematic review

Background

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with favorable short- and long-term oncological outcomes in highly selected patients with peritoneal metastasis (PM). The aim of our review was to review published, recruiting or ongoing randomized controlled trials (RCTs) evaluating CRS and HIPEC vs. other strategies (systemic chemotherapy or CRS alone) and to update the studies recently described in 2016.

Content

Systematic review according to PRISMA guidelines. Searches for published and ongoing trials were based, respectively, on PubMed and international clinical databases since 2016.

Summary

46 trials randomized 9,063 patients: 13 in colorectal cancer (3 in therapeutic strategy and 10 in prophylactic strategy), 16 in gastric cancer (4 in therapeutic strategy and 12 in prophylactic strategy) and 17 in ovarian cancer (12 in front-line therapy and 5 in recurrence settings).

Outlook

In contrast to many recruiting studies, few published studies analyzed the potential advantage of CRS and HIPEC in therapeutic and prophylactic treatment of PM. The potential effect of this combined treatment has been proven in ovarian cancer in interval surgery, but remains still debated in other situations. Promising trials are currently recruiting to provide further evidence of the effectiveness of CRS and HIPEC.

Validating the PSOGI classification of peritoneal disease from non-carcinoid epithelial appendiceal neoplasms in the curative and palliative setting: an observational retrospective study

BACKGROUND

Few studies on long-term survival have been published since the new updated pseudomyxoma peritonei (PMP) classification was published in 2016. The aim was to investigate long-term survival according to the Peritoneal Surface Oncology Group International (PSOGI) classification and compare prognostic factors.

METHODS

From Uppsala University Hospital, consecutive patients referred for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) from 2004 to 2017 with peritoneal disease from non-carcinoid mucinous epithelial appendiceal neoplasms were included in the study. The peritoneal disease was divided into four groups: mucin only, low-grade mucinous carcinoma peritonei (MCP-1), high-grade (MCP-2), and high-grade with signet ring cells (MCP-3). Survival curves were rendered, and prognostic factors were compared.

RESULTS

The study included 223 patients: 36 with mucin only, 112 with MCP-1, 70 with MCP-2, and 5 with MCP-3. Thirty-eight patients had a palliative debulking or open/close procedure. The 5- and 10-year overall survival was 97% and 97% for mucin only, 83% and 70% for MCP-1, 69% and 49% for MCP-2, with no patients still under follow-up after 5 years in the MCP-3 group. In a multivariable analysis, completeness of cytoreduction (CC) score 2-3 and PSOGI class MCP-3 were significantly associated with lower survival. The 5-year overall survival in the palliative setting was 40% vs. 44% (MCP-1 vs. MCP-2, P>0.05) with median survival 51 vs. 53 months, respectively.

CONCLUSIONS

The PSOGI classification of PMP provides a solid differentiation of prognostic groups after CRS/HIPEC treatment, but not in the palliative setting.

The Correlation Between Intra-Abdominal Pressure and Tolerance to Postoperative Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei

Objective

To evaluate the correlation between pain intensity and comfort level in patients with pseudomyxoma peritoneum (PMP) before and after hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods

From June 2018 to June 2019, patients who underwent HIPEC for PMP after surgical treatment in our institute were selected. The intra-abdominal pressure (IAP) and pain intensity (PI) before and after HIPEC were recorded, and the correlation between them was analyzed.

Results

Seventy-four patients received HIPEC 253 times. IAP and PI were significantly higher after perfusion than before perfusion (P < 0.05). When IAP < 12 cmH₂O, the change of PI was not correlated to the increase of IAP, and the patient tolerated the treatment. However, when IAP > 12 cmH₂O, the increase of PI was significantly associated with IAP and cause significant discomfort during the treatment.

Conclusion

IAP may be a monitoring index for the comfort of PMP patients during the postoperative HIPEC treatment.

Clinical Trial Protocol for HyNOVA: Hyperthermic and Normothermic intraperitoneal chemotherapy following interval cytoreductive surgery for stage III epithelial OVArian, fallopian tube and primary peritoneal cancer (ANZGOG1901/2020)

BACKGROUND

Ovarian cancer is the most lethal gynecological cancer, causing over 200,000 deaths worldwide in 2020. Initial standard treatment for primary ovarian cancer is optimal cytoreductive surgery (CRS) preceded and/or followed by intravenous platinum-based chemotherapy. However, most women develop recurrence within the peritoneal cavity and die of disease. Results of the OVIHIPEC 1 trial (2018) showed improved survival of 34% when hyperthermic intraperitoneal chemotherapy (HIPEC) was given immediately following interval-CRS in women with stage III disease. However, it is unknown if the effect of HIPEC is due to hyperthermia, one extra cycle of intraperitoneal (IP) chemotherapy, or other factors. There is also concern that hyperthermia might be associated with an increase in adverse events (AEs) due to a heightened systemic inflammatory response. HyNOVA is a seamless, multi-stage randomized study that attempts to answer these questions by comparing HIPEC to normothermic intraperitoneal chemotherapy (NIPEC), focusing on safety (stage 1), then assessing activity (stage 2) and effectiveness (stage 3). In this initial study, we hypothesize that NIPEC will result in a lower rate of severe AEs compared to HIPEC.

METHODS

This initial stage of HyNOVA is a phase II study of 80 women with International Federation of Gynaecology and Obstetrics stage III epithelial ovarian cancer, with at least stable disease following 3-4 cycles of neoadjuvant chemotherapy, achieving interval-CRS to <2.5 mm residual disease. Participants are randomized 1:1 to receive IP cisplatin 100 mg/m² for 90 minutes either as HIPEC, heated to 42°C (41.5°C-42.5°C), or NIPEC, at 37°C (36.5°C-37.5°C). The primary outcome is the proportion of AEs ≥ grade 3 occurring within 90 days. Secondary outcomes are AE of interest, surgical morbidity, patient reported outcomes, resource allocation, feasibility, progression-free survival and overall survival. AEs are measured using both CTCAE v5.0 and Clavien-Dindo classification, particularly infection, pain, bowel dysfunction, and anemia. Tertiary outcomes are potential predictive biomarkers measured before and after HIPEC/NIPEC including circulating cell-free tumor DNA, tissue factors, and systemic inflammatory markers. There are 4 participating Australian sites with experience in CRS and HIPEC for peritoneal malignancy. HyNOVA is funded by an MRFF grant (APP1199155).

TRIAL REGISTRATION

ANZCTR Identifier: ACTRN12621000269831.

Primary and metastatic peritoneal surface malignancies

Peritoneal surface malignancies comprise a heterogeneous group of primary tumours, including peritoneal mesothelioma, and peritoneal metastases of other tumours, including ovarian, gastric, colorectal, appendicular or pancreatic cancers. The pathophysiology of peritoneal malignancy is complex and not fully understood. The two main hypotheses are the transformation of mesothelial cells (peritoneal primary tumour) and shedding of cells from a primary tumour with implantation of cells in the peritoneal cavity (peritoneal metastasis). Diagnosis is challenging and often requires modern imaging and interventional techniques, including surgical exploration. In the past decade, new treatments and multimodal strategies helped to improve patient survival and quality of life and the premise that peritoneal malignancies are fatal diseases has been dismissed as management strategies, including complete cytoreductive surgery embedded in perioperative systemic chemotherapy, can provide cure in selected patients. Furthermore, intraperitoneal chemotherapy has become an important part of combination treatments. Improving locoregional treatment delivery to enhance penetration to tumour nodules and reduce systemic uptake is one of the most active research areas. The current main challenges involve not only offering the best treatment option and developing intraperitoneal therapies that are equivalent to current systemic therapies but also defining the optimal treatment sequence according to primary tumour, disease extent and patient preferences. New imaging modalities, less invasive surgery, nanomedicines and targeted therapies are the basis for a new era of intraperitoneal therapy and are beginning to show encouraging outcomes.

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.

Half of Postoperative Deaths After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Could be Preventable: A French Root Cause Analysis on 5562 Patients

OBJECTIVE

To perform a retrospective root-cause analysis of postoperative death after CRS and HIPEC procedures.

BACKGROUND

The combination of CRS and HIPEC is an effective therapeutic strategy to treat peritoneal surface malignancies, however it is associated with significant postoperative mortality.

METHODS

All patients treated with a combination of CRS and HIPEC between January 2009 and December 2018 in 22 French centers and died in the hospital, were retrospectively analyzed. Perioperative data of the 101 patients were collected by a local senior surgeon with a sole junior surgeon. Three independent experts investigated the typical root cause of death and provided conclusions on whether postoperative death was preventable (PREV group) or not (NON-PREV group). A typical root cause of preventable postoperative death was classified on a cause-and-effect diagram.

RESULTS

Of the 5562 CRS+HIPEC procedures performed, 101 in-hospital deaths (1.8%) were identified, of which a total of 18 patients of 70 years old and above and 20 patients with ASA score of 3. Etiology of peritoneal disease was mainly colorectal. A total of 54 patients (53%) were classified in the PREV group and 47 patients (47%) in the NON-PREV group. The results of the study show that in the PREV group, WHO performance status 1-2 was more frequent and the Median Peritoneal Cancer Index was higher compared with those of the NON-PREV group. The cause of death in the PREV group was classified as: (i) preoperatively for debatable indication (59%), (ii) intraoperatively (30%) and (iii) postoperatively in 17 patients (31%). A multifactorial cause of death was found in 11 patients (20%).

CONCLUSION

More than half of the postoperative deaths after combined CRS and HIPEC may be preventable, mainly by following guidelines regarding preoperative selection of the patients and adequate intraoperative decisions.