Randomized Controlled Trial Investigating Perioperative Immunonutrition for Patients Undergoing Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC).

BACKGROUND: Immunonutrition has been shown to reduce hospital stay and postoperative morbidity in patients undergoing gastrointestinal, and head and neck surgery. However, its use has not been demonstrated in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). This study aims to determine the effectiveness of perioperative immunonutrition on patients undergoing CRS-HIPEC in reducing length of hospitalization and postoperative complications. PATIENTS AND METHODS: From April 2017 to December 2018, patients undergoing CRS-HIPEC for peritoneal metastases in a single center were enrolled in a randomized controlled trial. Patients with evidence of intestinal obstruction or with diabetes mellitus were excluded. Patients were randomly assigned in a 1:1 fashion to receive perioperative oral immunonutrition or standard nutritional feeds. Length of hospital stay and rates of wound infection and complications were recorded and compared between the two groups in an intention-to-treat manner. RESULTS: A total of 62 patients were recruited and randomized into two groups. Compliance to nutritional feeds in the preoperative period was significantly higher in the standard nutrition group (95.2% versus 75.4%, p = 0.004). There was no difference in postoperative compliance rates. Length of hospital stay and rates of wound infection and postoperative complications were higher in the standard nutrition group when compared with patients on immunonutrition (15.5 versus 11.1 days, p = 0.186; 19% versus 9.7%, p = 0.473; 16% versus 9.7%, p = 0.653; respectively). CONCLUSIONS: Patients undergoing CRS-HIPEC who received perioperative immunonutrition had shorter hospitalization and less wound infections and postoperative complications, although the differences with the standard nutrition group were not statistically significant. Potential benefits of perioperative immunonutrition need to be further evaluated in larger studies.

Implications of peritoneal cancer index distribution on patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Objectives: Peritoneal cancer index (PCI) score is a common prognostication tool in peritoneal metastases (PM). We hypothesize that the distribution of PCI score and involvement of specific regions affects survival and morbidity outcomes. Methods: Data was collected from a prospective database of patients who underwent CRS and HIPEC for PM at the National Cancer Centre Singapore. We evaluate the relationship between PCI, PCI distribution, and survival and morbidity outcomes. Results: One hundred and fifty-two patients underwent CRS and HIPEC with a median PCI score of nine (range 0-31). Median overall survival (OS) and progression free survival (PFS) were 43 and 17 months, respectively. Region six (pelvis) was most commonly involved and had the highest frequency of heavy disease burden. Presence of PM in the lower abdomen, flanks, and small bowel were associated with poorer OS (p=0.01, 0.03, <0.001) and PFS (p=0.04, 0.02, <0.001). Involvement of porta hepatitis predicted poorer OS but not PFS (p=0.03). Involvement of the gastric antrum resulted in higher rates of postoperative complications. Conclusions: The pattern of PCI distribution may be associated with varying survival and morbidity outcomes.

Can baseline quality of life scores predict for morbidity and survival after CRS and HIPEC: a prospective study of 151 patients.

Objectives: Various studies have shown that good quality of life (QoL) can be achieved after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). There is prognostic value of baseline QoL in post-operative outcome in Western setting. Our prospective study aims to validate these observations and elucidate clinical factors that predict poorer QoL in Asian peritoneal carcinomatosis patients. Methods: European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire was administered to patients before CRS and HIPEC and thereafter at 3, 6 and 12 months. Results: A total of 151 patients underwent 155 surgeries. Four hundred and seventy two questionnaires were completed. Median disease-free survival (DFS) was 16.5 months. Three year DFS and overall survival (OS) were 24.0% and 73.0% respectively. Post-operative global health status significantly increased at 3, 6 and 12 months. The decreases in functional scales recovered to baseline by 1-year post-surgery. Peritoneal carcinomatosis index (PCI), presence of stoma, peritonectomy duration, death within one year, post-operative complication and length of SICU stay negatively influenced QoL. Complication rates were higher in patients with lower global health status, physical and role functioning scores and higher symptom summary scores at baseline. Lower social functioning score, and higher pain, dyspnoea and symptom summary scores at baseline were significantly associated with poorer OS. Conclusions: Various clinical factors can help us predict a patient's QoL after surgery. Several baseline factors were also able to predict morbidity and survival. Going forward, we can use these factors to help us better select patients who will have a greater benefit from CRS and HIPEC.

Prospective Comparison of the Performance of MRI Versus CT in the Detection and Evaluation of Peritoneal Surface Malignancies.

Background: The performance of MRI versus CT in the detection and evaluation of peritoneal surface malignancies (PSM) remains unclear in the current literature. Our study is the first prospective study in an Asian center comparing the two imaging modalities, validated against intra-operative findings. Methods: A total of 36 patients with PSM eligible for CRS-HIPEC underwent both MRI and CT scans up to 6 weeks before the operation. The scans were assessed for the presence and distribution of PSM and scored using the peritoneal cancer index (PCI), which were compared against PCI determined at surgery. Results: Both MRI and CT were 100% sensitive and specific in detecting the overall presence of PSM. Across all peritoneal regions, the sensitivity and specificity for PSM detection was 49.1% and 93.0% for MRI, compared to 47.8% and 95.1% for CT (p = 0.76). MRI was more sensitive than CT for small bowel disease, although the difference did not reach statistical significance. Comparing PCI on imaging with intra-operative PCI, the mean difference was found to be −3.4 ± 5.4 (p < 0.01) for MRI, and −3.9 ± 4.1 (p < 0.01) for CT. The correlation between imaging and intra-operative PCI was poor, with a concordance coefficient of 0.76 and 0.79 for MRI and CT, respectively. Within individual peritoneal regions, there was also poor agreement between imaging and intra-operative PCI for both modalities, other than in regions 1 and 3. Conclusion: MRI and CT are comparable in the detection and evaluation of PSM. While sensitive in the overall detection of PSM, they are likely to underestimate the true disease burden.

Ligand-mediated PAI-1 inhibition in a mouse model of peritoneal carcinomatosis.

Peritoneal carcinomatosis (PC) present a ubiquitous clinical conundrum in all intra-abdominal malignancies. Via functional and transcriptomic experiments of ascites-treated PC cells, we identify STAT3 as a key signaling pathway. Integrative analysis of publicly available databases and correlation with clinical cohorts (n = 7,359) reveal putative clinically significant activating ligands of STAT3 signaling. We further validate a 3-biomarker prognostic panel in ascites independent of clinical covariates in a prospective study (n = 149). Via single-cell sequencing experiments, we uncover that PAI-1, a key component of the prognostic biomarker panel, is largely secreted by fibroblasts and mesothelial cells. Molecular stratification of ascites using PAI-1 levels and STAT3 activation in ascites-treated cells highlight a therapeutic opportunity based on a phenomenon of paracrine addiction. These results are recapitulated in patient-derived ascites-dependent xenografts. Here, we demonstrate therapeutic proof of concept of direct ligand inhibition of a prognostic target within an enclosed biological space.

A machine learning approach to identify predictive molecular markers for cisplatin chemosensitivity following surgical resection in ovarian cancer.

Ovarian cancer is associated with poor prognosis. Platinum resistance contributes significantly to the high rate of tumour recurrence. We aimed to identify a set of molecular markers for predicting platinum sensitivity. A signature predicting cisplatin sensitivity was generated using the Genomics of Drug Sensitivity in Cancer and The Cancer Genome Atlas databases. Four potential biomarkers (CYTH3, GALNT3, S100A14, and ERI1) were identified and optimized for immunohistochemistry (IHC). Validation was performed on a cohort of patients (n = 50) treated with surgical resection followed by adjuvant carboplatin. Predictive models were established to predict chemosensitivity. The four biomarkers were also assessed for their ability to prognosticate overall survival in three ovarian cancer microarray expression datasets from The Gene Expression Omnibus. The extreme gradient boosting (XGBoost) algorithm was selected for the final model to validate the accuracy in an independent validation dataset (n = 10). CYTH3 and S100A14, followed by nodal stage, were the features with the greatest importance. The four gene signature had comparable prognostication as clinical information for two-year survival. Assessment of tumour biology by means of gene expression can serve as an adjunct for prediction of chemosensitivity and prognostication. Potentially, the assessment of molecular markers alongside clinical information offers a chance to further optimise therapeutic decision making.

Melanoma in Singapore: A 20-year review of disease and treatment outcomes.

INTRODUCTION: Melanomas in Asians have different clinicopathological characteristics and prognosis from melanomas in Caucasians. This study reviewed the epidemiology and treatment outcomes of cutaneous melanoma diagnosed at a tertiary referral dermatology centre in Singapore, which has a multiracial population. The study also determined whether Asians had comparable relapse-free and overall survival periods to Caucasians in Singapore. METHOD: This is a retrospective review of cutaneous melanoma cases in our centre between 1996 and 2015. RESULTS: Sixty-two cases of melanoma were diagnosed in 61 patients: 72.6% occurred in Chinese, 19.4% in Caucasians and 3.2% in Indians, with an over-representation of Caucasians. Superficial spreading melanoma, acral lentiginous melanoma and nodular melanoma comprised 37.1%, 35.5% and 22.6% of the cases, respectively. The median time interval to diagnosis was longer in Asians than Caucasians; median Breslow's thickness in Asians were significantly thicker than in Caucasians (2.6mm versus 0.9mm, P=0.018) and Asians tend to present at a later stage. The mortality rates for Asians and Caucasians were 52% and 0%, respectively. CONCLUSION: More physician and patient education on skin cancer awareness is needed in our Asian-predominant population for better outcomes.

Gene Expression Changes Associated with Dedifferentiation in Liposarcoma Predict Overall Survival.

Up to 10% of well-differentiated liposarcoma (WDLS) progress to dedifferentiated liposarcoma (DDLS). We aimed to identify gene expression changes associated with dedifferentiation and whether these were informative of tumour biology of DDLS. We analysed datasets from the Gene Expression Omnibus (GEO, ID = GSE30929) database to identify differentially expressed genes between WDLS (n = 52) and DDLS (n = 39). We validated the signature on whole and laser-capture microdissected samples from patients with tumours consisting of mixed WDLS and DDLS components. A subset of this signature was applied to an independent dataset from The Cancer Genome Atlas (TCGA, n = 58 DDLS) database to segregate samples based on gene expression and compared for recurrence and overall survival (OS). A 15-gene signature consisting of genes with increased expression in DDLS compared to WDLS was generated. This signature segregated WDLS and DDLS samples from patients with mixed component tumours and across multiple recurrences. A further subset of this signature, consisting of five genes (AQP7, ACACB, FZD4, GPD1, LEP), segregated DDLS in a TCGA cohort with a significant difference in OS (p = 0.019) and recurrence-free survival (RFS) (p = 0.061). The five-gene model stratified DDLS into prognostic groups and outperformed clinical factors in existing models in retroperitoneal DDLS.

Predicting Early and Late Readmissions Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

BACKGROUND: Postoperative readmissions not only burden the healthcare system but may also affect clinical outcomes of cancer patients. Despite this, little is known about readmissions after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), or their impact on survival outcomes. PATIENTS AND METHODS: A single-institution retrospective cohort study of CRS-HIPEC procedures from April 2001 and September 2019 was performed. Early readmission (ERA) was defined as hospitalization within 30 days of discharge post-CRS/HIPEC, while late readmission (LRA) was defined as hospitalization between day 31 and 90 after discharge. Patient demographic, oncological, and perioperative factors were analyzed to identify predictors of readmission, and comparison of survival outcomes was performed. RESULTS: Overall, 342 patients who underwent CRS-HIPEC were included in the study. The incidence of ERA and LRA was 18.5% and 7.4%, respectively. High-grade postoperative complication was the only independent predictor of ERA (HR 3.64, 95% CI 1.47-9.02), while comorbid hypertension (HR 2.71, 95% CI 1.17-6.28) and stoma creation (HR 2.83, 95% CI 1.23-6.50) were independent predictors for LRA. Patients with readmission had significantly worse disease-free survival than patients who had no readmission (NRA) (LRA 1.1 years, ERA 1.2 years, NRA 1.8 years, p = 0.002), and patients with LRA had worse median overall survival (2.1 years) than ERA patients (3.3 years) or patients without readmission (4.4 years) (p < 0.001). CONCLUSIONS: Readmission following CRS-HIPEC is associated with adverse survival outcomes. In particular, LRA may portend worse prognosis than ERA.

Postoperative Inflammatory Marker Surveillance in Colorectal Peritoneal Carcinomatosis.

BACKGROUND: The prognostic significance of inflammatory markers in solid cancers is well-established, albeit with considerable heterogeneity. This study sought to investigate the postoperative inflammatory marker trend in peritoneal carcinomatosis (PC), with a focus on colorectal PC (CPC), and to propose optimal surveillance periods and cutoffs. METHODS: Data were collected from a prospectively maintained database of PC patients treated at the authors' institution from April 2001 to March 2019. The platelet-lymphocyte ratio (PLR), the neutrophil-lymphocyte ratio (NLR), and the lymphocyte-monocyte ratio (LMR) were collected preoperatively and on postoperative days 0, 1 to 3, 4 to 7, 8 to 21, 22 to 56, and 57 to 90 as averages. Optimal surveillance periods and cutoffs for each marker were determined by maximally selected rank statistics. The Kaplan-Meier method and Cox proportional hazard regression models were used to investigate the association of inflammatory markers with 1-year overall survival (OS) and recurrence-free survival (RFS) using clinicopathologic parameters. RESULTS: The postoperative inflammatory marker trend and levels did not differ between the patients with and those without hyperthermic intraperitoneal chemotherapy (HIPEC). Low postoperative LMR (days 4-7), high postoperative NLR (days 8-21), and high postoperative PLR (days 22-56) were optimal for prognosticating poor 1-year OS, whereas high postoperative PLR and NLR (days 57-90) and low postoperative LMR (days 8-21) were associated with poor 1-year RFS. A composite score of these three markers was prognostic for OS in CPC. CONCLUSIONS: The reported cutoffs should be validated in a larger population of CPC patients. Future studies should account for the inflammatory response profile when selecting appropriate surveillance periods.

Neoadjuvant tyrosine kinase inhibitors in rectal gastrointestinal stromal tumours: a provision for enhanced oncological and functional outcomes.

BACKGROUND: The role of tyrosine kinase inhibitors (TKI) in the neoadjuvant setting and the optimal duration of therapy remains poorly defined. As such, we aim to evaluate the impact of neoadjuvant TKI on oncological and functional outcomes in our cohort of patients with rectal GISTs. METHODS: A retrospective analysis of 36 consecutive patients who underwent treatment for rectal GIST at the National Cancer Centre Singapore from February 1996 to October 2017 was analysed. Surgical, recurrence and survival outcomes between the groups who underwent neoadjuvant therapy and those who underwent upfront surgery were compared. RESULTS: Patients who received neoadjuvant treatment had significantly larger tumours (median size 7.1 vs. 6.0 cm, p = 0.04) and lower mitotic count (> 10 per 50 HPF, 14 vs. 70%, p = 0.03) when compared with the non-neoadjuvant group. With TKI pre-treatment (median duration 8.8 months), majority of patients (82%) achieved at least partial response to the therapy coupled with a significant downsizing effect of up to 39% (median size of 7.1-3.6 cm), resulting in similar rates of sphincter-sparing surgery (75 vs. 76%, p = 0.94) when compared with the non-neoadjuvant group. In general, neoadjuvant group had lower rates of local recurrence (0 vs. 69%, p = 0.04) and higher overall survival (7.4 vs. 5.7 years, p = 0.03) as compared to the non-neoadjuvant group. CONCLUSIONS: Neoadjuvant TKI has the benefit of downsizing unresectable rectal GIST to benefit from sphincter-sparing procedure and also confers protection against local recurrence and improves overall survival.

Palliative Gastrointestinal Surgery in Patients With Advanced Peritoneal Carcinomatosis: Clinical Experience and Development of a Predictive Model for Surgical Outcomes.

BACKGROUND: Palliative gastrointestinal (GI) surgery potentially relieves distressing symptoms arising from intestinal obstruction (IO) in patients with advanced peritoneal carcinomatosis (PC). As surgery is associated with significant morbidity risks in advanced cancer patients, it is important for surgeons to select patients who can benefit the most from this approach. Hence, we aim to determine predictors of morbidity and mortality after palliative surgery in patients with PC. In addition, we evaluate the utility of the UC Davis Cancer Care nomogram (UCDCCn) and develop a simplified model to predict short-term surgical mortality in these patients. METHODS: A retrospective review of patients with IO secondary to PC undergoing palliative GI surgery was performed. Logistic regression was used to determine independent predictors of 30-day morbidity and mortality after surgery. UCDCCn was evaluated using the area under the curve (AUC) for discriminatory power and the Hosmer-Lemeshow test for calibration. Our simplified model was developed using logistic regression and evaluated using cross-validation. RESULTS: A total of 254 palliative GI surgeries were performed over a 10-year duration. The 30-day morbidity and mortality were 43% (n = 110) and 21% (n = 53), respectively. Preoperative albumin, age, and emergency nature of surgery were significant independent predictors for 30-day morbidity. A simplified model using preoperative Eastern Cooperative Oncology Group (ECOG) status and albumin (AUC = 0.71) achieved better predictive power than UCDCCn (AUC = 0.66) for 30-day mortality. CONCLUSION: Good ECOG status and high preoperative albumin levels were independently associated with good short-term outcomes after palliative GI surgery. Our simplified model may be used to conveniently and efficiently select patients who stand to benefit the most from surgery.

Multiomic analysis and immunoprofiling reveal distinct subtypes of human angiosarcoma.

Angiosarcomas are rare, clinically aggressive tumors with limited treatment options and a dismal prognosis. We analyzed angiosarcomas from 68 patients, integrating information from multiomic sequencing, NanoString immuno-oncology profiling, and multiplex immunohistochemistry and immunofluorescence for tumor-infiltrating immune cells. Through whole-genome sequencing (n = 18), 50% of the cutaneous head and neck angiosarcomas exhibited higher tumor mutation burden (TMB) and UV mutational signatures; others were mutationally quiet and non-UV driven. NanoString profiling revealed 3 distinct patient clusters represented by lack (clusters 1 and 2) or enrichment (cluster 3) of immune-related signaling and immune cells. Neutrophils (CD15+), macrophages (CD68+), cytotoxic T cells (CD8+), Tregs (FOXP3+), and PD-L1+ cells were enriched in cluster 3 relative to clusters 2 and 1. Likewise, tumor inflammation signature (TIS) scores were highest in cluster 3 (7.54 vs. 6.71 vs. 5.75, respectively; P < 0.0001). Head and neck angiosarcomas were predominant in clusters 1 and 3, providing the rationale for checkpoint immunotherapy, especially in the latter subgroup with both high TMB and TIS scores. Cluster 2 was enriched for secondary angiosarcomas and exhibited higher expression of DNMT1, BRD3/4, MYC, HRAS, and PDGFRB, in keeping with the upregulation of epigenetic and oncogenic signaling pathways amenable to targeted therapies. Molecular and immunological dissection of angiosarcomas may provide insights into opportunities for precision medicine.

Retrospective quality of life study in patients with retroperitoneal sarcoma in an Asian population.

BACKGROUND: Retroperitoneal sarcoma represents 15% of sarcomas. The mainstay of treatment is surgery where a majority of patients require multi-visceral resections that may significantly impact their quality of life (QOL) following surgery. Studies in other cancers have shown that QOL may not be significantly impacted after radical or extensive surgery. However, there are limited studies examining the QOL specifically in patients with retroperitoneal sarcoma. In this pilot study, we retrospectively evaluated the QOL of patients with retroperitoneal sarcoma. METHODS: 32 out of 90 patients who underwent surgical intervention for retroperitoneal sarcoma in National Cancer Centre Singapore from January 1999 to August 2018 who were alive and on follow-up were included in this study. EORTC-QLQ-C30 was administered to the patients. RESULTS: The median age of our patients was 59 years (range, 35-84), and median time from surgery to the implementation of questionnaire was 2.5 years (range, 0.05-9.6). Younger patients had significantly better differences in global health, physical and role functioning scores as compared to older individuals. Female patients reported higher global health, physical, emotional and social functioning scores than males. Patients who were more than 2 years post-surgery exhibited better QOL scores as compared to those who had more recent surgery. Our patients had comparable global health and functioning scores compared to a reference group of outpatient cancer patients at our institution. CONCLUSIONS: Our pilot study investigating the QOL of patients with retroperitoneal sarcoma has shown that patients need to be followed up for at least 2 years following surgery to evaluate their QOL. In general, they achieved better functioning scores when compared with other cancer patients. These findings support the need for larger-scale prospective studies to further evaluate the QOL of these patients.

Management of synchronous lateral pelvic nodal metastasis in rectal cancer in the era of neoadjuvant chemoradiation: A systemic review.

BACKGROUND: Lateral pelvic lymph node (LLN) metastasis (LLNM) occur in up to 28% of patients with low rectal tumours. While prophylactic lateral pelvic lymph node dissection (LLND) has been abandoned by most western institutions in the era of neoadjuvant chemoradiation therapy (CRT), the role of selective LLND in patients with enlarged LLN on pre-CRT imaging remains unclear. Some studies have shown improved survival and recurrence outcomes when LLNs show "response" to CRT. However, no management algorithm exists to differentiate treatment for "responders" vs "non-responders". AIM: To determine if selective LLND in patients with enlarged LLNs results in improved survival and recurrence outcomes. METHODS: A systemic search of PubMed and Embase databases for studies reporting on patients with synchronous radiologically suspicious LLNM (s-LLNM) in rectal cancer receiving preoperative-CRT was performed. RESULTS: Fifteen retrospective, single-centre studies were included. 793 patients with s-LLNM were evaluated: 456 underwent TME while 337 underwent TME with LLND post-CRT. In the TME group, local recurrence (LR) rates range from 12.5% to 36%. Five-year disease free survival (DFS) was 42% to 75%. In the TME with LLND group, LR rates were 0% to 6%. Five years DFS was 41.2% to 100%. Radiological response was seen in 58%. Pathologically positive LLN was found in up to 94% of non-responders vs 0% to 20% in responders. Young age, low tumour location and radiological non-response were associated with final positive LLNM and lowered DFS. CONCLUSION: LLND is associated with local control in patients with s-LLNM. It can be performed in radiological non-responders given a large majority represent true LLNM. Its role in radiological responders should be considered in selected high risk patients.

Axillary Lymph Node Dissection in Angiosarcomas of the Breast: An Asian Institutional Perspective.

Angiosarcomas of the breast (ASB) are rare, making up to less than 8% of all angiosarcomas. The surgical management for this disease continues to vary throughout centres worldwide due to the current limited evidence. We aim to examine the necessity of axillary lymph node dissection in this pathology through a retrospective study of axillary metastasis and recurrence patterns in patients treated at our institution. A retrospective review of a prospectively-maintained database was performed. All adult patients with a histologically confirmed diagnosis of ASB seen at the National Cancer Centre Singapore between 2006 and 2019 were identified. Axillary lymph node status, treatment, survival, and recurrence data were collated. Thirteen patients were identified with a confirmed diagnosis of ASB, of which there were 11 primary and 2 secondary angiosarcoma cases. Eight patients had some form of axillary lymph node dissection and 5 did not. No positive nodes were found in any examined axillary nodes despite high median number of nodes harvested (13, range 8-24). 5/13 patients had disease progression, of whom none had locoregional recurrence to the axilla. ASB continues to be rare and recurrent and presents as a challenge to treat. Axillary lymph node involvement is most likely not present in a majority of patients. Prophylactic removal is unwarranted in patients presenting without lymph node involvement due to the lack of axillary metastasis.

Novel prognostic score for outcomes after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal cancer with metachronous peritoneal carcinomatosis.

BACKGROUND: This study aimed to determine pre- and peri-operative parameters with significant predictive value for post-operative outcomes in patients with recurrent colorectal cancer presenting as peritoneal carcinomatosis undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), and to develop a novel prognostic scoring system for prediction of survival outcomes. METHODS: A single-institution review of prospectively collected data from all patients who underwent CRS-HIPEC between October 2005 and October 2017 was conducted. Univariate and multivariate analyses were used to identify significant parameters for prediction of post-CRS-HIPEC disease-free survival and overall survival (OS). RESULTS: A total of 278 patients underwent CRS-HIPEC, of whom 72 were for peritoneal carcinomatosis from recurrent colorectal cancer. Disease-free interval (DFI; P = 0.006), peritoneal cancer index (PCI; P = 0.001) and left upper quadrant disease (P = 0.023) were significant independent predictors of 3-year OS. DFI (0.007), PCI (P < 0.001) and intraoperative blood loss (BL; P = 0.001) were significant independent predictors of 5-year OS. PCI and BL were significant independent predictors of both 3-year (P = 0.026, PCI; P = 0.009, BL) and 5-year (P = 0.002, PCI; P = 0.011, BL) disease-free survival. Predictive models were developed for risk stratification of OS. CONCLUSION: PCI, DFI, left upper quadrant disease and BL have significant predictive value for post-CRS-HIPEC outcomes. Risk stratification models allow for more prudent patient selection and ultimately more accurate prognostication of post-operative outcomes.

The importance of synchronicity in the management of colorectal peritoneal metastases with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

BACKGROUND: Colorectal peritoneal metastases (CPM) occur in up to 13% of patients with colorectal cancer, presenting either synchronously or metachronously. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) have been increasingly utilised for selected CPM patients with favourable outcomes, though its benefits may differ for synchronous (s-CPM) and metachronous CPM (m-CPM). METHODS: A retrospective analysis of CPM patients treated with CRS and HIPEC at the National Cancer Centre Singapore over 15 years was performed. In the s-CPM group, CPM was diagnosed at primary presentation with CRS and HIPEC performed at the time of or within 6 months from primary surgery. In the m-CPM group, patients developed CPM > 6 months after primary curative surgery. RESULTS: One hundred two patients with CPM were treated with CRS and HIPEC. Twenty (19.6%) patients had s-CPM and 82 (80.4%) had m-CPM. Recurrences occurred in 45% of s-CPM and in 54% of m-CPM (p = 0.619). Median overall survival was significantly prolonged in patients with m-CPM (45.2 versus 26.9 months, p = 0.025). In a subset of m-CPM patients with limited PCI in whom ICU stay was not required, a survival advantage was seen (p = 0.031). CONCLUSION: A survival advantage was seen a subset of m-CPM patients, possibly representing differences in disease biology.