Correlation of Morphological Appearance of Peritoneal Lesions at Laparotomy and Disease at Pathological Assessment in Patients Undergoing Cytoreductive Surgery for Peritoneal Malignancy: Results of Phase I of the PRECINCT Study in 707 Patients.

BACKGROUND: The PRECINCT (Pattern of peritoneal dissemination and REsponse to systemic Chemotherapy IN Common and uncommon peritoneal Tumors) is a prospective, multicenter, observational study. This report from phase I of PRECINCT outlines variations in recording the surgical peritoneal cancer index (sPCI) at experienced peritoneal malignancy centers and the incidence of pathologically confirmed disease in morphologically different peritoneal lesions (PL). METHODS: The sPCI was recorded in a prespecified format that included the morphological appearance of PL. Six prespecified morphological terms were provided. The surgical and pathological findings were compared. RESULTS: From September 2020 to December 2021, 707 patients were enrolled at 10 centers. The morphological details are routinely recorded at two centers, structure bearing the largest nodule, and exact size of the largest tumor deposit in each region at four centers each. The most common morphological terms used were normal peritoneum in 3091 (45.3%), tumor nodules in 2607 (38.2%) and confluent disease in 786 (11.5%) regions. The incidence of pathologically confirmed disease was significantly higher in 'tumor nodules' with a lesion score of 2/3 compared with a lesion score of 1 (63.1% vs. 31.5%; p < 0.001). In patients receiving neoadjuvant chemotherapy, the incidence of pathologically confirmed disease did not differ significantly from those undergoing upfront surgery [751 (47.7%) and 532 (51.4%) respectively; p = 0.069]. CONCLUSIONS: The sPCI was recorded with heterogeneity at different centers. The incidence of pathologically confirmed disease was 49.2% in 'tumor nodules'. Frozen section could be used more liberally for these lesions to aid clinical decisions. A large-scale study involving pictorial depiction of different morphological appearances and correlation with pathological findings is indicated.

Neoadjuvant chemotherapy does not improve survival for patients with high volume colorectal peritoneal metastases undergoing cytoreductive surgery.

BACKGROUND: Colorectal peritoneal metastases (CRPM) affects 15% of patients at initial colorectal cancer diagnosis. Neoadjuvant chemotherapy (NAC) prior to cytoreductive surgery (CRS) has been demonstrated to be a safe and feasible option, however there is limited data describing its efficacy in advanced peritoneal disease. This study evaluated the effect of NAC on survival in patients with high volume CRPM undergoing CRS with or without HIPEC. METHODS: A retrospective review of all patients who underwent CRS with or without HIPEC for CRPM from 2004 to 2019 at our institution was performed. The cohort was divided based on peritoneal carcinomatosis index (PCI) at surgery: Low Volume (PCI ≤ 16) and High Volume (PCI > 16). RESULTS: A total of 326 patients underwent CRS with HIPEC for CRPM. There were 39 patients (12%) with High Volume disease, and 15 of these (38%) received NAC. Patients with High Volume disease had significantly longer operating time, lower likelihood of complete macroscopic cytoreduction (CC-0 score), longer intensive care unit length of stay and longer hospital stay compared to Low Volume disease. In High Volume disease, the NAC group had a significantly shorter median survival of 14.4 months compared to 23.8 months in the non-NAC group (p = 0.046). CONCLUSION: Patients with High Volume CRPM achieved good median survival following CRS with HIPEC, which challenges the current PCI threshold for offering CRS. The use of NAC in this cohort did not increase perioperative morbidity but was associated with significantly shorter median survival compared to upfront surgery.

Controversy Over Liver Transplantation or Resection for Neuroendocrine Liver Metastasis: Tumor Biology Cuts the Deal.

BACKGROUND: In patients with neuroendocrine liver metastasis (NELM), liver transplantation (LT) is an alternative to liver resection (LR), although the choice of therapy remains controversial. In this multicenter study, we aim to provide novel insight in this dispute. METHODS: Following a systematic literature search, 15 large international centers were contacted to provide comprehensive data on their patients after LR or LT for NELM. Survival analyses were performed with the Kaplan-Meier method, while multivariable Cox regression served to identify factors influencing survival after either transplantation or resection. Inverse probability weighting and propensity score matching was used for analyses with balanced and equalized baseline characteristics. RESULTS: Overall, 455 patients were analyzed, including 230 after LR and 225 after LT, with a median follow-up of 97 months [95% confidence interval (CI): 85-110 months]. Multivariable analysis revealed G3 grading as a negative prognostic factor for LR [hazard ratio (HR)=2.22, 95% CI: 1.04-4.77, P =0.040], while G2 grading (HR=2.52, 95% CI: 1.15-5.52, P =0.021) and LT outside Milan criteria (HR=2.40, 95% CI: 1.16-4.92, P =0.018) were negative prognostic factors in transplanted patients. Inverse probability-weighted multivariate analyses revealed a distinct survival benefit after LT. Matched patients presented a median overall survival (OS) of 197 months (95% CI: 143-not reached) and a 73% 5-year OS after LT, and 119 months (95% CI: 74-133 months) and a 52.8% 5-year OS after LR (HR=0.59, 95% CI: 0.3-0.9, P =0.022). However, the survival benefit after LT was lost if patients were transplanted outside Milan criteria. CONCLUSIONS: This multicentric study in patients with NELM demonstrates a survival benefit of LT over LR. This benefit depends on adherence to selection criteria, in particular low-grade tumor biology and Milan criteria, and must be balanced against potential risks of LT.

The CEA/PCI ratio is a superior prognosticator than mCOREP for colorectal cancer patients with peritoneal carcinomatosis.

Background: The CEA/PCI ratio, which evaluates tumour marker and burden, has been demonstrated as a prognosticator for patients with colorectal cancer with peritoneal carcinomatosis. The aim of this study was to compare the CEA/PCI ratio with the Modified Colorectal Peritoneal Score (mCOREP) for overall survival (OS) and recurrence free survival (RFS). There is no literature currently comparing both markers for RFS. Methods: Data was collected retrospectively for patients undergoing CRS and hyperthermic intraperitoneal chemotherapy (HIPEC) at the Peritonectomy Unit at St. George Hospital, NSW from January 2015 to December 2021. Results: From 187 patients, an increase in CEA/PCI ratio was associated with reduced OS (p < 0.01) and RFS (p < 0.01), whereas mCOREP score did not demonstrate such association with OS (p = 0.5) nor RFS (p = 0.4). However, CEA/PCI ratio greater than the median of 0.63 was correlated with an increased OS (p = 0.01), whereas the mCOREP greater than the median of 4 correlated with reduced OS (p < 0.01). Median mCOREP also demonstrated association with reduced RFS in patients with PCI <15 (p = 0.03), whereas CEA/PCI ratio above 0.63 demonstrated association with reduced RFS in patients with PCI ≥ 15 (p = 0.02). Conclusion: The CEA/PCI ratio is more associated with OS and RFS in patients with colorectal cancer with peritoneal carcinomatosis, when compared with mCOREP. CEA/PCI ratio above 0.63 was correlated with increased OS, whereas mCOREP above 4 is correlated with reduced OS. CEA/PCI ratio above 0.63 demonstrated reduced RFS for patients with higher PCIs. By contrast, mCOREP >4 illustrated reduced RFS in patients with lower PCIs.

Outcomes for Colorectal Cancer Cases With Peritoneal Metastases Treated With Cytoreductive Surgery With or Without Hyperthermic Intraperitoneal Chemotherapy: A Comparative Analysis of Survival Between Peritoneal Carcinomatosis Scores - PCI in a Single Centre.

BACKGROUND/AIM: Peritoneal cancer index (PCI) has been a strong indicator of prognosis for patients receiving cytoreductive surgery. The aim of this single institution study was to compare the survival of peritoneal carcinoma cases treated with cytoreduction surgery arising from colorectal cancer grouped by PCI scores. PATIENTS AND METHODS: A retrospective study of a prospective dataset maintained from 2000 till September 2022, for peritoneal metastases from colorectal cancers was carried out. Of the total of 1,625 peritoneal metastases cases, 415 were identified with colorectal cancer and considered for analysis. Survival was followed for 60 months since the index-peritonectomy for cases in this study. RESULTS: Hazard ratio for 5-year survival using the Cox regression analysis over time (t) with a Log-rank (Mantel-Cox) test for significance between the groups indicated, <15 vs. 15 (HR=2.121, p=0.0338), <15 vs. 16-20 (HR=2.748, p<0.0001), <15 vs. >20 (HR=3.158, p<0.0001), 15 vs. 16-20 (HR=1.262, p=0.5658), 15 vs. >20 (HR=1.566, p=0.2771) and for PCI category 16-20 vs. >20 (HR=1.204, p=0.5355) for survival. Median survival for the categories of PCI <15, PCI-15, PCI-16-20, and PCI >15 was 43.967 (95%CI=28.31-59.63), 20.67 (95%CI=5.01-36.33), 19.50 (95%CI=3.84-35.16), and 14.30 (95%CI=1.36-29.96), respectively. CONCLUSION: A correlation of PCI with survival was confirmed in this study reinforcing the need for assessment of PCI at surgery to help prognostication. Detecting synchronous peritoneal metastases early and prompt treatment can help prevent recurrence and increase survival.

Increased Incidence of Liver Metastases in Colorectal Versus Appendiceal Adenocarcinoma Peritonectomy Patients Despite Equivocal Survival.

BACKGROUND/AIM: Colorectal adenocarcinoma (CRAdenoCa) and appendiceal adenocarcinoma (AAdenoCa) are diseases of the same histopathological type that metastasise to the liver and peritoneum. In selected subgroups, peritonectomy and heated intraperitoneal chemotherapy (HIPEC) may be indicated as part of the multimodal treatment plan. However, literature comparing the survival outcomes and preoperative tumour activity and burden of CRAdenoCa and AAdenoCa peritonectomy patients without synchronous liver metastases (sLM) is scarce. Little is also known about the comparative incidence of sLM and metachronous LM (mLM) between CRAdenoCa and AAdenoCa peritonectomy patients. This study aimed to clarify the above. PATIENTS AND METHODS: A retrospective cohort study of 684 CRAdenoCa and AAdenoCa primary peritonectomy patients between 2001-2021 was conducted at St George Hospital in Sydney, Australia. RESULTS: Median overall survival (years) was equivocal between CRAdenoCa and AAdenoCa peritonectomy patients (1.7 vs. 1.9, p=0.35). Peritoneal cancer index and preoperative carcinoembryonic antigen (CEA) were significantly elevated (25 vs. 9, p<0.0001 and 7.9 vs. 5, p=0.0080) in AAdenoCa versus CRAdenoCa peritonectomy patients without sLM. The incidence of sLM and mLM was increased in CRAdenoCa peritonectomy patients (24% vs. 3.1%, p<0.0001 and 26% vs. 10%, p=0.0001). CONCLUSION: This study demonstrates similar survival outcomes between CRAdenoCa and AAdenoCa peritonectomy patients. Despite elevated preoperative tumour burden and biological activity in AAdenoCa patients, CRAdenoCa patients had higher rates of sLM and mLM. Further studies are warranted to validate and identify cellular and molecular targets that increase CRAdenoCa's ability to metastasise to the liver.

The 'Starburst' Sign: A Novel Description of PET Images in Carcinoma of Unknown Primary.

BACKGROUND/AIM: Carcinoma of unknown primary (CUP) poses a formidable diagnostic challenge, characterised by high mortality rates and an elusive primary tumour site. While Positron emission tomography (PET) scans are routinely employed in the initial evaluation of CUP patients, identifying the primary tumour remains an ongoing struggle. In light of this, the aim of this case report is to introduce a novel radiological description, termed the 'Starburst' sign, derived from distinctive PET scan appearances associated with CUP. CASE REPORT: In this report, we present the case of a 47-year-old female patient who presented with abdominal symptoms. Upon investigation, extensive peritoneal disease was observed, yet the primary tumour source remained unidentified. Despite further diagnostic efforts, including a normal gastroscopy, a PET scan was able to confirm the presence of high-volume metastatic disease, without an identifiable primary tumour. Palliative treatment was initiated, but unfortunately, the patient's condition deteriorated rapidly, leading to her demise. CONCLUSION: The 'Starburst' sign, a unique radiological description of CUP in PET scans, has significant potential in advancing our understanding of the disease. It provides a visual analogy to a dying star, aiding comprehension of complex pathophysiology and implications of metastatic lesions. The introduction of the 'Starburst' sign benefits patients and healthcare professionals, enhancing education, assessment, and treatment of CUP. This novel description contributes to knowledge in the field and can impact clinical management.

Survival benefits with EPIC in addition to HIPEC for low grade appendiceal neoplasms with pseudomyxoma peritonei: a propensity score matched study.

Objectives: Appendiceal cancer is a rare malignancy, occurring in roughly 1.2 per 100,000 per year. Low grade appendiceal neoplasams (LAMN) in particular can lead to pseudomyxoma peritonei (PMP), and respond poorly to systemic chemotherapy. Standard treatment includes cytoreduction surgery (CRS) with addition of heated intraoperative peritoneal chemotherapy (HIPEC). Several centres include early postoperative intraperitoneal chemotherapy (EPIC) however; the literature is mixed on the benefits. We aim to examine the benefits of additional EPIC through a propensity-matched analysis. Methods: Patients with LAMN with PMP who underwent cytoreductive surgery at St George hospital between 1996 and 2020 were included in this retrospective analysis. Propensity score matching was performed with the following used to identify matched controls; sex, age, American Society of Anesthesiologists (ASA) grade, peritoneal cancer index (PCI) and morbidity grade. Outcomes measured included length of stay and survival. Results: A total of 224 patients were identified of which 52 received HIPEC alone. Propensity matching was performed to identify 52 matched patients who received HIPEC + EPIC. Those receiving HIPEC + EPIC were younger at 54.3 vs. 58.4 years (p=0.044). There was a median survival benefit of 34.3 months for HIPEC + EPIC (127.3 vs. 93.0 months, p=0.02). Median length of stay was higher in those who received EPIC (25.0 vs. 23.5 days, p=0.028). Conclusions: In LAMN with PMP, the addition of EPIC to HIPEC with CRS improves overall survival in propensity score matched cases but results in prolonged hospitalisation. The use of EPIC should still be considered in selected patients.

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.

Peritoneal metastasis of advanced epithelial ovarian carcinoma treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: A retrospective international multicentric data analysis.

INTRODUCTION: The purpose of our study was to evaluate outcome data after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with peritoneal metastasis originating from advanced epithelial ovarian carcinoma (PMOC). PATIENTS AND METHODS: A retrospective international multi-institutional registry was established through collaborative efforts of participating units affiliated with the Peritoneal Surface Oncology Group. RESULTS: One thousand four hundred and ninety-one patients from 11 specialized units underwent CRS and HIPEC that of those 326 (21.9%) upfront surgeries, 504 (33.8%) interval surgery, and 661(44.3%) recurrent cases. Complete Cytoreduction(CC0/1) was achieved in 1213 patients (81.3%). Treatment -related mortality was 0.8%, major operative complications (Grades 3-5) was 25.1%. Factors associated with major operative complications include prior surgical score (PSS for recurrent cases; RC) PSS>2,p = 0.000), PCI(≤15, >15 cut-off level; p ≤ 0.000), completeness of cytoreduction (CC, p=0.000), high CA125 levels (>25 mg/dl), presence of ascites, high CRP (>5 mg/dl) levels and low albumin levels (below to 2.5 mg/dl) (p ≤ 0.05). The median survival was 58 months in upfront surgery(UFS), 60 months in interval surgery(IS), and 42 months in RC. The overall survival for five years was 45% for UFS, 37% for IS, 28% for RC cases. CCscore (p = 0.000), CA125, CRP and albumin levels (p ≤ 0.05) were predictors for progression free survival. PCI(p ≤ 0.000), major postoperative complications (p = 0.004), incomplete CRS(CC2/3)(p < 0.001), prior chemotherapy (hazard ratio [HR], 3-8; p < 0.001) and PSS>2 for RC were independent predictors of poor overall survival. CONCLUSION: The combined treatment strategy for PMOC may be performed safely with acceptable morbidity and mortality in the specialized units.

Case series on high grade appendiceal cancer with peritoneal and liver carcinomatosis undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC).

BACKGROUND: Pseudomyxoma Peritonei (PMP) is a mucin producing cancer with appendix as primary site. Cytoreductive Surgery (CRS) combined with hyper-thermic intraperitoneal chemotherapy (HIPEC) is an established form of therapy known to prolong survival in patients with PMP and peritoneal carcinomatosis. Methods/patients In our case series, we present five cases of PMP with synchronous liver and peritoneal metastasis treated with CRS and HIPEC. It is a very rare condition which needs more research to be able to comment on overall survival. RESULTS: However, in our study, we found lower age, female gender and complete cytoreduction in surgery to be favourable predictors for improved morbidity. CONCLUSION: In our experience, CRS/HIPEC seem to be feasible for patients with PMP with synchronous liver and peritoneal metastasis.

Cytoreductive Surgery and HIPEC for Malignant Peritoneal Mesothelioma: Outcomes and Survival From an Australian Centre.

BACKGROUND/AIM: The aim of the study was to determine outcomes and overall survival (OS) in patients undergoing cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) for malignant peritoneal mesothelioma (MPM). PATIENTS AND METHODS: This was a retrospective cohort study from a prospectively maintained database of patients that underwent CRS/HIPEC for MPM from April 1999 to December 2021. RESULTS: A total of 81 patients were identified with MPM. Median OS was 53 months with a 1-, 3- and 5-year OS of 76%, 55% and 49% respectively. Multivariate analysis identified lymph node status, PCI and CC score as statistically significant prognostic factors that impact survival. Median OS for PCI 0-20 was 103 months vs. 33 months for PCI 21-39 (p=0.005). Median OS for CC0, CC1 and CC2 were 104, 30 and 2.7 months respectively (p<0.001). Hazard ratio for node-positive disease over node-negative was 2.14 (95% CI=1.07-4.31, p<0.033). Grade III/IV complication rate was 43.2% and mortality 4.9%. CONCLUSION: CRS/HIPEC remains the gold standard for treating patients with MPM with excellent patient OS. Lymph node status, PCI and CC score were independent prognostic factors that affect OS.

Second-look Surgery for Appendiceal High Grade and Colorectal Cancers Following Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC).

BACKGROUND/AIM: Up to a third of patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis (PC) of appendiceal or colorectal origin receive a stoma during primary surgery. Stoma reversal provides an opportunity for second-look surgery. PATIENTS AND METHODS: We performed a retrospective analysis of prospectively collected data of patients with colorectal cancer (CRC) or high-grade appendiceal cancer (AC) from 2006 to 2021 from our database. A total of 34 consecutive stoma closure patients with no evidence of preoperative disease recurrence (tumor markers and CT scans) were compared with 141 consecutive re-do CRS/HIPEC patients with known recurrence. RESULTS: Eleven patients (32.4%) were identified to have peritoneal recurrence at stoma closure. Time between first and second CRS was 12 months (4 to 64.2) in the stoma closure group vs. 24.6 months (5.8 to 119.8) in the re-do group, while median peritoneal cancer index (PCI) was 4 (3 to 6) vs. 8 (1 to 39), respectively (p=0.0143). CONCLUSION: Second-look laparotomy during stoma closure identified unexpected PC in 32.4% of our patients with significantly lower PCI than planned re-do operations.

Cost-effectiveness of Iterative Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for the Treatment of Peritoneal Carcinomatosis.

BACKGROUND: Iterative cytoreduction (iCRS) and hyperthermic intraperitoneal chemotherapy is a treatment for recurrence of peritoneal carcinomatosis. There are considerable upfront costs for this approach for which the cost-effectiveness has not been evaluated. PATIENTS AND METHODS: We used a prospectively maintained database of patients having undergone primary and iterative cytoreduction at St. George Hospital between January 1, 2014, and December 31, 2017, which was linked with financial data. Cost effectiveness and survival outcomes were used to compare primary cytoreduction (pCRS) and iterative cytoreduction (iCRS) in addition to comparison with other treatment modalities. RESULTS: The average cost per patient in Australian dollars was $69,295 ($14,691-$696,002) and the average cost per life-year was $15,842. There was no difference in cost-effectiveness between those who had undergone pCRS and those who had undergone iCRS. The overall survival was 52.5 months (95% confidence interval=49.7-55.2 months) with no difference in survival between pCRS and iCRS groups. The median length of hospital stay was significantly longer for patients in the pCRS treatment group (25.51 days) when compared to the iCRS treatment group (21.15 days, p=0.034). CONCLUSION: iCRS is a cost-effective treatment in the management of recurrent peritoneal carcinomatosis.

Risk factors and clinical outcomes in patients undergoing cytoreductive surgery with concomitant ureteric reimplantation.

OBJECTIVES: There are currently scarce data exploring ureteric reimplantation (UR) during cytoreductive surgery (CRS). METHODS: We identified patients undergoing CRS for peritoneal surface malignancies (PSM) of any origin at a single high-volume unit. UR was defined as ureteroureterostomy, transureterouretostomy, ureteroneocystostomy, ureterosigmoidostomy or ileal conduit performed during CRS. Peri-operative outcomes, long-term survival and risk factors for requiring UR were analysed. RESULTS: Seven hundred and sixty-seven CRSs were identified. Twenty-three (3.0%) procedures involved UR. Bladder resection and colorectal cancer (CRC) were associated with increased risk of UR (bladder resection: OR 12.90, 95% CI 4.91-33.90, p<0.001; CRC: OR 2.51, 95% CI 1.05-6.01, p=0.038). UR did not increase the risk of Grade III-IV morbidity or mortality. The rate of ureteric leak was 3/23 (13.0%) in the UR group. Mean survival was equivocal in patients with CRC (58.14 vs. 34.25 months, p=0.441) but significantly lower in those with high-grade appendiceal mucinous neoplasm (HAMN) undergoing UR (73.98 vs. 30.90 months, p=0.029). CONCLUSIONS: UR during CRS does not increase major morbidity or mortality for carefully selected patients, and is associated with low rates of urologic complications. Whilst decreased survival was apparent in patients with HAMN undergoing UR, it is unclear whether this relationship is causal.

Peritoneal Spread of Low-grade Appendiceal Tumours - 2 Days of Early Postoperative Intra-peritoneal Chemotherapy Are Enough.

BACKGROUND/AIM: While controversial, cytoreductive surgery (CRS) with heated intra-peritoneal chemotherapy (HIPEC) and early postoperative intra-peritoneal chemotherapy (EPIC) remains the mainstay of treatment for low grade appendiceal neoplasm with pseudomyxoma peritonei (PMP). Our study aimed to investigate the difference in survival when administering HIPEC alone vs. HIPEC + EPIC. Additionally, we examined whether the duration of EPIC affects survival. PATIENTS AND METHODS: We compared the difference in survival in 238 patients who underwent CRS + HIPEC alone vs. CRS + HIPEC/EPIC combination for low grade appendiceal cancer. We also compared short course (1-2 days) vs. long course (3-5 days) of EPIC. RESULTS: HIPEC/EPIC combination group (n=179) showed a significantly better 5-year survival of 95% compared to 71% in HIPEC alone (n=59). There was no statistically significant difference in 5-year survival between short course (n=22) and long course of EPIC (n=157). CONCLUSION: Combined use of HIPEC and EPIC improves 5-year survival in low-grade appendiceal neoplasm. Two days of EPIC are sufficient.

Patterns of peritoneal dissemination and response to systemic chemotherapy in common and rare peritoneal tumours treated by cytoreductive surgery: study protocol of a prospective, multicentre, observational study.

INTRODUCTION: Despite optimal patient selection and surgical effort, recurrence is seen in over 70% of patients undergoing cytoreductive surgery (CRS) for peritoneal metastases (PM). Apart from the Peritoneal Cancer Index (PCI), completeness of cytoreduction and tumour grade, there are other factors like disease distribution in the peritoneal cavity, pathological response to systemic chemotherapy (SC), lymph node metastases and morphology of PM which may have prognostic value. One reason for the underutilisation of these factors is that they are known only after surgery. Identifying clinical predictors, specifically radiological predictors, could lead to better utilisation of these factors in clinical decision making and the extent of peritoneal resection performed for different tumours. This study aims to study these factors, their impact on survival and identify clinical and radiological predictors. METHODS AND ANALYSIS: There is no therapeutic intervention in the study. All patients with biopsy-proven PM from colorectal, appendiceal, gastric and ovarian cancer and peritoneal mesothelioma undergoing CRS will be included. The demographic, clinical, radiological, surgical and pathological details will be collected according to a prespecified format that includes details regarding distribution of disease, morphology of PM, regional node involvement and pathological response to SC. In addition to the absolute value of PCI, the structures bearing the largest tumour nodules and a description of the morphology in each region will be recorded. A correlation between the surgical, radiological and pathological findings will be performed and the impact of these potential prognostic factors on progression-free and overall survival determined. The practices pertaining to radiological and pathological reporting at different centres will be studied. ETHICS AND DISSEMINATION: The study protocol has been approved by the Zydus Hospital ethics committee (27 July, 2020) and Lyon-Sud ethics committee (A15-128). TRIAL REGISTRATION NUMBER: CTRI/2020/09/027709; Pre-results.