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.

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.

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.

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.

Evaluating geographical disparities on clinical outcomes following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

BACKGROUND: Rural Australians typically encounter disparities in healthcare access leading to adverse health outcomes, delayed diagnosis and reduced quality of life (QoL) parameters. These disparities may be exacerbated in advanced malignancies, where treatment is only available at highly specialised centres with appropriate multidisciplinary expertise. Thus, this study aims to determine the association between patient residence on oncological, surgical and QoL outcomes following cytoreductive surgery (CRS) and hyperthermic intra-peritoneal chemotherapy (HIPEC). METHODS: A retrospective analysis was conducted on consecutive patients undergoing CRS and HIPEC at Royal Prince Alfred Hospital from January 2017 to March 2022. On the basis of their postcode of residence, patients were stratified into metropolitan and regional groups. Data encompassing demographics, oncological, surgical and QoL outcomes were compared. Statistical analysis included chi-square test, t-tests and Kaplan-Meier survival curves. RESULTS: Among the 317 patients, 228 (72%) were categorised as metropolitan and 89 (28%) as regional. Metropolitan patients presented higher rates of recurrence (61.8% versus 40.0%, p = 0.014) and shorter overall mean survival [3.8 years (95% CI: 3.44-4.09) versus 4.2 years (95% CI: 3.76-4.63), p = 0.019] compared with regional patients. No other statistically significant differences were observed in oncological, surgical and QoL outcomes. CONCLUSIONS: Most oncological, surgical and QoL parameters did not differ by geographical location of patients undergoing CRS and HIPEC for peritoneal malignancies at a high-volume quaternary referral centre. Observed differences in recurrence and survival may be attributed to the selective nature of surgical referrals and variable follow-up patterns. Future research should focus on characterising referral pathways and its influence on post-operative outcomes.

Can the Heald anal stent help to reduce anastomotic or rectal stump leak in elective and emergency colorectal surgery? A single-center experience.

Anastomotic and rectal stump leaks are feared complications of colorectal surgery. Diverting stomas are commonly used to protect low rectal anastomoses but can have adverse effects. Studies have reported favorable outcomes for transanal drainage devices instead of diverting stomas. We describe our use of the Heald anal stent and its potential impact in reducing anastomotic or rectal stump leak after elective or emergency colorectal surgery. We performed a single-center retrospective analysis of patients in whom a Heald anal stent had been used to "protect" a colorectal anastomosis or a rectal stump, in an elective or emergency context, for benign and malignant pathology. Intraoperative and postoperative outcomes were reviewed using clinical and radiological records. The Heald anal stent was used in 93 patients over 4 years. Forty-six cases (49%) had a colorectal anastomosis, and 47 (51%) had an end stoma with a rectal stump. No anastomotic or rectal stump leaks were recorded. We recommend the Heald anal stent as a simple and affordable adjunct that may decrease anastomotic and rectal stump leak by reducing intraluminal pressure through drainage of fluid and gas.

Evaluating analgesia strategies in patients who have undergone oesophagectomy-a systematic review and network meta-analysis of randomised clinical trials.

Optimal pain control following esophagectomy remains a topic of contention. The aim was to perform a systematic review and network meta-analysis (NMA) of randomized clinical trials (RCTs) evaluating the analgesia strategies post-esophagectomy. A NMA was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-NMA guidelines. Statistical analysis was performed using Shiny and R. Fourteen RCTs which included 565 patients and assessed nine analgesia techniques were included. Relative to systemic opioids, thoracic epidural analgesia (TEA) significantly reduced static pain scores at 24 hours post-operatively (mean difference (MD): -13.73, 95% Confidence Interval (CI): -27.01-0.45) (n = 424, 12 RCTs). Intrapleural analgesia (IPA) demonstrated the best efficacy for static (MD: -36.2, 95% CI: -61.44-10.96) (n = 569, 15 RCTs) and dynamic (MD: -42.90, 95% CI: -68.42-17.38) (n = 444, 11 RCTs) pain scores at 48 hours. TEA also significantly reduced static (MD: -13.05, 95% CI: -22.74-3.36) and dynamic (MD: -18.08, 95% CI: -31.70-4.40) pain scores at 48 hours post-operatively, as well as reducing opioid consumption at 24 hours (MD: -33.20, 95% CI: -60.57-5.83) and 48 hours (MD: -42.66, 95% CI: -59.45-25.88). Moreover, TEA significantly shortened intensive care unit (ICU) stays (MD: -5.00, 95% CI: -6.82-3.18) and time to extubation (MD: -4.40, 95% CI: -5.91-2.89) while increased post-operative forced vital capacity (MD: 9.89, 95% CI: 0.91-18.87) and forced expiratory volume (MD: 13.87, 95% CI: 0.87-26.87). TEA provides optimal pain control and improved post-operative respiratory function in patients post-esophagectomy, reducing ICU stays, one of the benchmarks of improved post-operative recovery. IPA demonstrates promising results for potential implementation in the future following esophagectomy.

MRI-predicted extramural vascular invasion and tumour deposit are main predictors of disease-free survival in patients undergoing surgical resection for rectal cancer.

BACKGROUND: MRI is crucial in staging patients with rectal cancer and planning treatment. The aim was to analyse the prognostic role of MRI-predicted tumour deposits and/or extramural vascular invasion (mrTD/EMVI) in a cohort of patients with rectal cancer undergoing surgical resection, with selective neoadjuvant chemoradiotherapy (nCRT). METHOD: Retrospective analysis of a single-centre cohort of consecutive patients with rectal cancer undergoing low anterior resection or abdominoperineal excision between 2008 and 2020. Unit policy was selective nCRT for MRI-predicted threatened or involved circumferential resection margin (mrCRM), or radiologically involved pelvic sidewall nodes. The primary outcome was disease-free survival. Secondary outcomes were rates of local recurrence, distant recurrence and overall survival. RESULTS: A total of 314 patients were analysed. Median age was 65 years (female/male: 114/200). A total of 54/314 (17%) had nCRT and 35 patients (11%) underwent abdominoperineal excision. Median follow-up was 64 months. Overall, local recurrence was detected in 18/314 (5.7%) and distant recurrence in 45/314 (14.3%). In patients not receiving nCRT (n = 260), local recurrence was detected in 11/260 (4.2%) and distant recurrence in 35/260 (13.5%). Disease-free survival was 80.5% at 5 years. Specifically, disease-free survival was 89% in mrTD/EMVI-negative and mrCRM-negative, 67% in mrTD/EMVI-positive and mrCRM-negative, and 64% in the mrCRM-positive rectal cancer (log-rank, P < 0.001). On multivariable Cox-regression analysis mrTD/EMVI was the only MRI variable associated with disease-free survival (hazard ratio 2.95; P < 0.001). CONCLUSION: mrTD/EMVI is a major prognostic indicator. Rectal cancer patients with mrCRM-negative and mrTD/EMVI-negative have excellent long-term outcomes with surgery alone. Patients with mrTD/EMVI-positive should be selectively stratified for neoadjuvant treatments in future clinical trials.

A global analysis of nutrition support practices in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignancy.

BACKGROUND: Perioperative nutritional care has been identified as an important factor in the management of patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Nevertheless, there is no published consensus on best practice for nutritional management specific to this patient group. The purpose of this study was to identify the current nutrition care practices among international centres performing CRS and HIPEC for patients with peritoneal malignancy. METHODS: An online survey was developed and sent to experienced CRS and HIPEC centres. The survey questions covered clinician and institution demographics, formal nutrition care pathways, pre-operative nutrition care, post-operative nutrition support and post-discharge nutritional follow-up. RESULTS: Eighty-two centres were contacted, and 42 responses were received. Respondents were from 20 different countries and were mostly dietitians (71%). Nutrition assessments were frequently completed (52% pre-operatively and 86% post-operatively) and most centres used a validated nutrition screening or assessment tool (79%). Perioperative nutrition support with respect to the use of enteral nutrition, parenteral nutrition and enhanced recovery after surgery varied widely between centres. The use of routine parenteral and enteral nutrition was significantly higher in Europe compared with other locations (p = 0.028). CONCLUSIONS: Nutrition care is pivotal and has been positively integrated into the complex management of patients undergoing CRS and HIPEC globally, however variation in practice is evident. The findings highlight a unique opportunity to collaboratively investigate the role nutrition plays in determining outcomes and to identify the most appropriate nutrition support methods to achieve improved clinical outcomes for these high-risk patients.

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.

Potential of damage associated molecular patterns in synergising radiation and the immune response in oesophageal cancer.

BACKGROUND: There is an intimate crosstalk between cancer formation, dissemination, treatment response and the host immune system, with inducing tumour cell death the ultimate therapeutic goal for most anti-cancer treatments. However, inducing a purposeful synergistic response between conventional therapies and the immune system remains evasive. The release of damage associated molecular patterns (DAMPs) is indicative of immunogenic cell death and propagation of established immune responses. However, there is a gap in the literature regarding the importance of DAMP expression in oesophageal adenocarcinoma (OAC) or by immune cells themselves. AIM: To investigate the effects of conventional therapies on DAMP expression and to determine whether OAC is an immunogenic cancer. METHODS: We investigated the levels of immunogenic cell death-associated DAMPs, calreticulin (CRT) and HMGB1 using an OAC isogenic model of radioresistance. DAMP expression was also assessed directly using ex vivo cancer patient T cells (n = 10) and within tumour biopsies (n = 9) both pre and post-treatment with clinically relevant chemo(radio)therapeutics. RESULTS: Hypoxia in combination with nutrient deprivation significantly reduces DAMP expression by OAC cells in vitro. Significantly increased frequencies of T cell DAMP expression in OAC patients were observed following chemo(radio)therapy, which was significantly higher in tumour tissue compared with peripheral blood. Patients with high expression of HMGB1 had a significantly better tumour regression grade (TRG 1-2) compared to low expressors. CONCLUSION: In conclusion, OAC expresses an immunogenic phenotype with two distinct subgroups of high and low DAMP expressors, which correlated with tumour regression grade and lymphatic invasion. It also identifies DAMPs namely CRT and HMGB1 as potential promising biomarkers in predicting good pathological responses to conventional chemo(radio)therapies currently used in the multimodal management of locally advanced disease.

Correlation between PSOGI pathological classification and survival outcomes of patients with pseudomyxoma peritonei treated using cytoreductive surgery and HIPEC: national referral centre experience and literature review.

Objectives: The Peritoneal Surface Oncology Group International (PSOGI) consensus subdivided pseudomyxoma peritonei (PMP) into four groups according to histopathological features. The aim of this paper is to report survival outcomes after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) from a national referral centre and to correlate the PSOGI classification with survival. Methods: A retrospective study of a prospectively maintained database was performed. Consecutive patients treated with CRS + HIPEC for PMP of appendiceal origin were included (September-2013 to December-2021). Pathological features of the peritoneal disease were used to classify patients into the four groups proposed by PSOGI. Survival analysis was performed to evaluate the correlation of pathology on overall survival (OS) and disease-free survival (DFS). Results: Overall, 104 patients were identified; 29.6 % were reclassified as acellular mucin (AM), 43.9 % as low-grade mucinous carcinoma peritonei (LGMCP), 22.4 % as high-grade MCP (HGMCP) and 4.1 % as HGMCP with signet ring cells (HGMCP-SRC). Median PCI and rate of optimal cytoreduction were 19 and 82.7 %, respectively. Median OS and DFS were not reached, 5-year OS and DFS were 88.6(SD 0.04) % and 61.6(SD 0.06) %, respectively. Log-Rank test revealed significant differences in terms of OS and DFS across the different histological subgroups (p<0.001 in both cases). However, histology did not retain its significance in the multivariate analysis for OS or DFS (p=0.932 and p=0.872, respectively). Conclusions: Survival outcomes after CRS + HIPEC for PMP are excellent. The PSOGI pathological classification correlates with OS and DFS, but differences were not significant at multivariate analysis when adjusted for other prognostic factors.

PD-1 blockade attenuates surgery-mediated immunosuppression and boosts Th1 immunity perioperatively in oesophagogastric junctional adenocarcinoma.

Introduction: This timely study assesses the immunosuppressive effects of surgery on cytotoxic Th1-like immunity and investigates if immune checkpoint blockade (ICB) can boost Th1-like immunity in the perioperative window in upper gastrointestinal cancer (UGI) patients. Methods: PBMCs were isolated from 11 UGI patients undergoing tumour resection on post-operative days (POD) 0, 1, 7 and 42 and expanded ex vivo using anti-CD3/28 and IL-2 for 5 days in the absence/presence of nivolumab or ipilimumab. T cells were subsequently immunophenotyped via flow cytometry to determine the frequency of T helper (Th)1-like, Th1/17-like, Th17-like and regulatory T cell (Tregs) subsets and their immune checkpoint expression profile. Lymphocyte secretions were also assessed via multiplex ELISA (IFN-γ, granzyme B, IL-17 and IL-10). The 48h cytotoxic ability of vehicle-, nivolumab- and ipilimumab-expanded PBMCs isolated on POD 0, 1, 7 and 42 against radiosensitive and radioresistant oesophageal adenocarcinoma tumour cells (OE33 P and OE33 R) was also examined using a cell counting kit-8 (CCK-8) assay to determine if surgery affected the killing ability of lymphocytes and whether the use of ICB could enhance cytotoxicity. Results: Th1-like immunity was suppressed in expanded PBMCs in the immediate post-operative setting. The frequency of expanded circulating Th1-like cells was significantly decreased post-operatively accompanied by a decrease in IFN-γ production and a concomitant increase in the frequency of expanded regulatory T cells with an increase in circulating levels of IL-10. Interestingly, PD-L1 and CTLA-4 immune checkpoint proteins were also upregulated on expanded Th1-like cells post-operatively. Additionally, the cytotoxic ability of expanded lymphocytes against oesophageal adenocarcinoma tumour cells was abrogated post-surgery. Of note, the addition of nivolumab or ipilimumab attenuated the surgery-mediated suppression of lymphocyte cytotoxicity, demonstrated by a significant increase in tumour cell killing and an increase in the frequency of Th1-like cells and Th1 cytokine production. Conclusion: These findings support the hypothesis of a surgery-mediated suppression in Th1-like cytotoxic immunity and highlights a rationale for the use of ICB within the perioperative setting to abrogate tumour-promoting effects of surgery and ameliorate the risk of recurrence.