The contemporary management of peritoneal metastasis: A journey from the cold past of treatment futility to a warm present and a bright future.

Peritoneal metastasis (PM) is often regarded as a less frequent pattern of spread; however, collectively across all spectra of primary tumors, the consequences of PM impact a large population of patients annually. Unlike other modes of metastasis, symptoms at presentation or during the treatment course are common, representing an additional challenge in the management of PM. Early efforts with chemotherapy and incomplete surgical interventions transiently improved symptoms, but durable symptom control and survival extension were rare, which established a perspective of treatment futility for PM through most of the 20th century. Notably, the continued development of better systemic therapy combinations, optimization of cytoreductive surgery (CRS), and rigorous investigation of combining regional therapy-specifically hyperthermic intraperitoneal chemotherapy-with CRS, have resulted in more effective multimodal treatment options for patients with PM. In this article, the authors provide a comprehensive review of the data establishing the contemporary approach for tumors with a high frequency of PM, including appendix, colorectal, mesothelioma, and gastric cancers. The authors also explore the emerging role of adding hyperthermic intraperitoneal chemotherapy to the well established paradigm of CRS and systemic therapy for advanced ovarian cancer, as well as the recent clinical trials identifying the efficacy of poly(adenosine diphosphate ribose) polymerase maintenance therapy. Finally, recent data are included that explore the role of precision medicine technology in PM management that, in the future, may help further improve patient selection, identify the best systemic therapy regimens, detect actionable mutations, and identify new targets for drug development.

Phase 1 trial of intraperitoneal paclitaxel in patients with gastric adenocarcinoma and carcinomatosis or positive cytology.

BACKGROUND: The purpose of this phase 1 trial was to evaluate the safety and toxicity of repeated normothermic intraperitoneal paclitaxel (PTX) for patients with gastric cancer metastatic to the peritoneum. METHODS: A Bayesian optimal interval design was used to prospectively identify the safety and tolerability of escalating doses of intraperitoneal paclitaxel at weekly treatments for 3 weeks, followed by a 1-week break, and then three additional treatments. The primary objective was to define the maximum tolerated dose. Secondary end points included safety, tolerability, and antitumor activity. RESULTS: A total of 25 patients were treated between January 2020 and April 2023. Five dose-limiting toxicities were observed at 100 mg/m2. Treatment-related grade 3-4 toxicity included leukopenia (32%) and neutropenia (32%). Seven patients required a schedule change to every other week treatments. The maximum tolerated dose for intraperitoneal PTX was 100 mg/m2. The peritoneum post-intraperitoneal PTX demonstrated progression in five (20%), stable disease in five (20%), improvement in 10 (40%), and not evaluable in five (20%). Eight patients (32%) had resolution of their peritoneal disease and seven (28%) underwent attempted resection. The median overall survival (OS) from the diagnosis of metastatic disease was 18.8 months and from the date of treatment initiation was 10.8 months. One-, 2-, and 3-year OS rates from the diagnosis of metastatic disease were 84%, 38%, and 25%, respectively. CONCLUSIONS: Paclitaxel may be safely used at intraperitoneal doses of 100 mg/m2. Neutropenia associated with weekly treatments was common. Peritoneal complete clinical response rates with multimodality therapy including PTX were promising.

Cytoreduction and Hyperthermic Intraperitoneal Paclitaxel and Cisplatin for Gastric Cancer with Peritoneal Metastasis.

BACKGROUND: Peritoneal metastasis (PM) is the most common site of dissemination of gastric cancer (GC) and is associated with a poor prognosis. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for GC with PM remains controversial due to modest survival and significant morbidity. METHODS: We conducted a retrospective analysis of patients with GC and PM treated with CRS and HIPEC with cisplatin and paclitaxel for 90 min from June 2019 to December 2022. RESULTS: Twenty-two patients were included and received a median of 7 (interquartile range [IQR] 4-8) cycles of neoadjuvant systemic therapy. Seventeen patients (77%) underwent a single neoadjuvant laparoscopic HIPEC, and six (27%) patients received chemoradiation. The median Peritoneal Carcinomatosis Index at the time of CRS was 1 (IQR 0-4), and 21 patients (95%) underwent complete cytoreduction (CC-0). An R0 resection was achieved in 20 (91%) patients, and the median length of stay was 5.5 (IQR 4-7.5) days. There were six (27%) 90-day major complications (Clavien-Dindo grade ≥ 3), one (4%) Common Terminology Classification for Adverse Events (CTCAE) grade 4 cytopenia, and one (4%) acute kidney injury. The rate of anastomotic leak (all grades) was 14%, the 30-day readmission rate was 18%, and the 90-day mortality rate was 0%. At a median follow-up of 24 months, the median progression-free survival (PFS) and overall survival (OS) were not reached. The 1-, 2-, and 3-year PFS rates were 65%, 56%, and 40%, respectively, and the 1-, 2-, and 3-year OS rates were 96%, 78%, and 55%, respectively. CONCLUSIONS: CRS and HIPEC with paclitaxel and cisplatin is well tolerated and is associated with favorable oncologic and perioperative outcomes.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: HIPEC Technologies.

This manuscript reports the results of an international consensus on technologies of hyperthermic intraperitoneal perioperative chemotherapy (HIPEC) performed with the following goals: To provide recommendations for the technological parameters to perform HIPEC. To identify the role of heat and its application forms in treating peritoneal metastases. To provide recommendations regarding the correct dosimetry of intraperitoneal chemotherapy drugs and their carrier solutions. To identify for each intraperitoneal chemotherapy regimen the best dosimetry and fractionation. To identify areas of future research pertaining to HIPEC technology and regimens. This consensus was performed by the Delphi technique and comprised two rounds of voting. In total, 96 of 102 eligible panelists replied to both Delphi rounds (94.1%) with a consensus of 39/51 questions on HIPEC technical aspects. Among the recommendations that met with the strongest consensus were those concerning the dose of HIPEC drug established in mg/m2, a target temperature of at least 42°C, and the use of at least three temperature probes to pursue hyperthermia. Ninety minutes as the ideal HIPEC duration seemed to make consensus. These results should be considered when designing new clinical trials in patients with peritoneal surface malignancies.

Insight into Predictors of Cytoreduction Score Following Cytoreductive Surgery-Hyperthermic Intraperitoneal Chemotherapy for Gastric Peritoneal Carcinomatosis Improves Patient Selection and Prognostic Outcomes.

BACKGROUND: Peritoneal metastases due to gastric adenocarcinoma (GCPM) carry a dismal prognosis. A promising treatment strategy is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), but clear eligibility criteria for GCPM are lacking. We sought to identify factors associated with overall survival (OS) following CRS-HIPEC for GCPM to help optimize patient selection and clinical outcomes. PATIENTS AND METHODS: In this single-center retrospective cohort study, we examined CRS-HIPEC outcomes for patients with GCPM between 2001 and 2021. After analyzing patient demographic, clinicopathologic, and perioperative variables, we applied multivariable Cox hazard models to assess factors associated with OS. We then assessed associations between baseline predictors and prognostically important variables using multivariable logistic regression. RESULTS: We analyzed 55 patients with GCPM who underwent CRS-HIPEC. Median age was 54 years and 42% were female. Median peritoneal carcinomatosis index (PCI) was 8, and 75% of patients achieved a cytoreduction completeness score (CC score) of 0. Median progression-free survival (PFS) was 6.9 months, and median OS was 14.1 months. On adjusted analysis, a CC score > 0 (HR 2.3, p = 0.02) was significantly associated with worse OS. A peritoneal carcinomatosis index greater than 13 (OR 52.6, p = 0.001) and fewer lymph nodes (especially < 18) resected with the primary tumor (OR 0.86, p = 0.042) in the metachronous setting were significantly associated with incomplete macroscopic cytoreduction (CC score > 0). CONCLUSIONS: We demonstrated that PCI > 13 and primary lymph nodes harvested < 18 in metachronous tumors are associated with CC score > 0, which in turn portends a worse OS. Although these results warrant prospective validation, they provide insight into improved selection of patients with GCPM for CRS-HIPEC.

Cytoreductive Surgery with Bidirectional Intraoperative Chemotherapy (BDIC) Using Intravenous Ifosfamide Plus Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Patients with Peritoneal Sarcomatosis: A Retrospective Cohort Study.

BACKGROUND: Peritoneal sarcomatosis (PS) is a rare tumor with limited therapeutic options. Bidirectional intraoperative chemotherapy (BDIC) using intravenous ifosfamide and doxorubicin-based hyperthermic intraperitoneal chemotherapy (HIPEC) after cytoreductive surgery (CRS) is an emerging treatment for peritoneal malignancies. PATIENTS AND METHODS: Patients with PS who underwent CRS/BDIC using intravenous ifosfamide and HIPEC from January 2017 to July 2021 were retrospectively analyzed. The last follow-up date was May 2022. RESULTS: A total of 29 patients were included. Overall survival (OS) rates at 6, 12, 24, and 48 months after CRS/BDIC were 93.1%, 89.2%, 81.4%, and 73.3%, respectively. As of May 2022, 6 patients (20.6%) had died, including four (13.8%) with a proven recurrent tumor and two with incomplete tumor resection [completeness of cytoreduction (CC)-2 or CC-3]. Of the 20 patients (68.9%) with CC-0 or CC-1, 7 had locoregional tumor recurrence without distant metastasis, whereas the other 13 were alive with no evidence of recurrent tumor in May 2022. Disease recurrence rates were 15% at 6 months and 35% at 12, 24, and 48 months after CRS/BDIC. Clavien-Dindo class ≥ IIIa complications developed in 9 patients (31.0%) with no deaths. Leukopenia occurred in 5 patients (17.2%) and thrombocytopenia in 12 patients (41.3%); these hematologic abnormalities resolved. A total of 9 (31.0%) patients developed nephrotoxicity; all recovered except one, who progressed to chronic kidney disease. CONCLUSIONS: CRS/BDIC using intravenous ifosfamide and doxorubicin-based HIPEC is a potentially effective treatment for PS and has an acceptable rate of complications.

2022 Peritoneal Surface Oncology Group International Consensus on HIPEC Regimens for Peritoneal Malignancies: Colorectal Cancer.

BACKGROUND: Selected patients with peritoneal metastases of colorectal cancer (PM-CRC) can benefit from potentially curative cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC), with a median overall survival (OS) of more than 40 months. OBJECTIVE: The aims of this evidence-based consensus were to define the indications for HIPEC, to select the preferred HIPEC regimens, and to define research priorities regarding the use of HIPEC for PM-CRC. METHODS: The consensus steering committee elaborated and formulated pertinent clinical questions according to the PICO (patient, intervention, comparator, outcome) method and assessed the evidence according to the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework. Standardized evidence tables were presented to an international expert panel to reach a consensus (4-point, weak and strong positive/negative) on HIPEC regimens and research priorities through a two-round Delphi process. The consensus was defined as ≥ 50% agreement for the 4-point consensus grading or ≥ 70% for either of the two combinations. RESULTS: Evidence was weak or very weak for 9/10 clinical questions. In total, 70/90 eligible panelists replied to both Delphi rounds (78%), with a consensus for 10/10 questions on HIPEC regimens. There was strong negative consensus concerning the short duration, high-dose oxaliplatin (OX) protocol (55.7%), and a weak positive vote (53.8-64.3%) in favor of mitomycin-C (MMC)-based HIPEC (preferred choice: Dutch protocol: 35 mg/m2, 90 min, three fractions), both for primary cytoreduction and recurrence. Determining the role of HIPEC after CRS was considered the most important research question, regarded as essential by 85.7% of the panelists. Furthermore, over 90% of experts suggest performing HIPEC after primary and secondary CRS for recurrence > 1 year after the index surgery. CONCLUSIONS: Based on the available evidence, despite the negative results of PRODIGE 7, HIPEC could be conditionally recommended to patients with PM-CRC after CRS. While more preclinical and clinical data are eagerly awaited to harmonize the procedure further, the MMC-based Dutch protocol remains the preferred regimen after primary and secondary CRS.

Decision Regret in Patients with Appendiceal Cancer Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

BACKGROUND: Decision regret is an emerging patient reported outcome. The aim of this study was to assess the incidence of regret in patients with appendiceal cancer (AC) who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). PATIENTS AND METHODS: An anonymous survey was distributed to patients through the Appendix Cancer and Pseudomyxoma Peritonei (ACPMP) Research Foundation. The Decision Regret Scale (DRS) was employed, with DRS > 25 signifying regret. Patient demographics, tumor characteristics, postoperative outcomes, symptoms (FACT-C), and PROMIS-29 quality of life (QoL) scores were compared between patients who regretted or did not regret (NO-REG) the procedure. RESULTS: A total of 122 patients were analyzed. The vast majority had no regret about undergoing CRS-HIPEC (85.2%); 18 patients expressed regret (14.8%). Patients with higher regret had: income ≤ $74,062 (72.2% vs 44.2% NO-REG; p = 0.028), major complications within 30 days of surgery (55.6% vs 15.4% NO-REG; p < 0.001), > 30 days hospital stay (38.9% vs 4.8% NO-REG; p < 0.001), a new ostomy (27.8% vs 7.7% NO-REG; p = 0.03), >1 CRS-HIPEC procedure (56.3% vs 12.6% NO-REG; p < 0.001). Patients with worse FACT-C scores had more regret (p < 0.001). PROMIS-29 QOL scores were universally worse in patients with regret. Multivariable analysis demonstrated > 30 days in the hospital, new ostomy and worse gastrointestinal symptom scores were significantly associated with regret. CONCLUSIONS: The majority of patients with AC undergoing CRS-HIPEC do not regret undergoing the procedure. Lower income, postoperative complications, an ostomy, undergoing > 1 procedure, and with worse long-term gastrointestinal symptoms were associated with increased regret. Targeted perioperative psychological support and symptom management may assist to ameliorate regret.

Metastatic Colorectal Cancer Treated with Combined Liver Resection, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): Predictive Factors for Early Recurrence.

BACKGROUND: Selection of colorectal cancer patients with concomitant peritoneal (PM) and liver metastases (LM) for radical treatment with cytoreductive surgery (CRS), including liver resection and hyperthermic intraperitoneal chemotherapy (HIPEC), needs improvement. This retrospective, monocentric study was designed to evaluate the predictive factors for early recurrence, disease-free survival (DFS), and overall survival (OS) in such patients treated in a referral center. METHODS: Consecutive colorectal cancer patients with concomitant LM and PM treated with curative intent with perioperative systemic chemotherapy, simultaneous complete CRS, liver resection, and HIPEC in 2011-2022 were included. Clinical, radiological (before and after preoperative chemotherapy), surgical, and pathological data were investigated, along with long-term oncologic outcomes. A multivariate analysis was performed to identify predictive factors associated with early recurrence (diagnosed <6 months after surgery), DFS, and OS. RESULTS: Of more than 61 patients included, 31 (47.1%) had pT4 and 27 (40.9%) had pN2 primary tumors. Before preoperative chemotherapy, the median number of LM was 2 (1-4). The median surgical PCI (peritoneal carcinomatosis index) was 3 (5-8.5). The median DFS and OS were 8.15 (95% confidence interval [CI] 5.5-10.1) and 34.1 months (95% CI 28.1-53.5), respectively. In multivariate analysis, pT4 (odds ratio [OR] = 4.14 [1.2-16.78], p = 0.032]) and pN2 (OR = 3.7 [1.08-13.86], p = 0.042) status were independently associated with an early recurrence, whereas retroperitoneal lymph node metastasis (hazard ratio [HR] = 39 [8.67-175.44], p < 0.001) was independently associated with poor OS. CONCLUSIONS: In colorectal cancer patients with concomitant PM and LM, an advanced primary tumor (pT4 and/or pN2) was associated with a higher risk of early recurrence following a radical multimodal treatment, whereas RLN metastases was strongly detrimental for OS.

Predictive Value of C-Reactive Protein for Infectious Complications After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: A Single-Center Prospective Study.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can be associated with significant morbidity and prolonged hospital stay. Postoperative infections account for a high burden of these complications. This study aimed to assess the predictive value of postoperative C-reactive protein (CRP) levels for overall infectious complications and anastomotic leaks. METHODS: This was a single-center prospective study of patients undergoing CRS and HIPEC for peritoneal metastases between 2018 and 2020 at Maisonneuve-Rosemont Hospital in Montreal, QC, Canada. CRP levels were measured daily for 10 days following surgery. A comparison was made between patients with infectious complications and those without. RESULTS: Ninety-nine patients were included. Thirty patients had infectious complications (30.3%) and four patients presented an anastomotic leak (4%). CRP levels were significantly higher in patients with infectious complications from postoperative days (PODs) 2-10. Daily cut-off values most accurately predicted infectious complications on day 8 (94.3 mg/L; area under the curve [AUC] 0.85, sensitivity [SE] 76.2%, specificity [SP] 94.7%, positive predictive value [PPV] 88.9%, negative predictive value [NPV] 87.8%; p < 0.0001) and day 9 (72.7 mg/L; AUC 0.89, SE 95.2%, SP 81.8%, PPV 76.9%, NPV 96.4%; p < 0.0001). Patients with infectious complications had longer operative time, higher peritoneal cancer index, and a higher number of intestinal anastomoses, while their baseline characteristics were comparable. CONCLUSION: Measurement of CRP helps predict infectious complications following CRS and HIPEC, particularly on PODs 8 and 9. Cut-off values are more accurate after the first postoperative week, especially in ruling out infectious complications.

Comparison of EPIC Versus HIPEC in the Treatment of Colorectal Peritoneal Metastases and Appendix Tumors Using Inverse Probability of Treatment Weighting.

BACKGROUND: The selection of hyperthermic intraperitoneal chemotherapy (HIPEC) or early postoperative intraperitoneal chemotherapy (EPIC) for peritoneal metastases from colorectal cancer or appendiceal neoplasms following cytoreductive surgery (CRS) depends on the surgeon's discretion. This study was designed to compare postoperative and oncologic outcomes of HIPEC and EPIC using inverse probability of treatment weighting (IPTW). METHODS: This study included 175 patients who received HIPEC or EPIC following CRS at a single tertiary university hospital between December 1999 and December 2020. Inverse probability of treatment weighting analysis was performed to control for pretreatment characteristics between the two groups. Multivariate analysis was performed to determine factors associated with postoperative and survival outcomes. RESULTS: After IPTW, no significant differences in baseline demographics and tumor characteristics were observed between the two groups. The HIPEC group had a significantly longer operation time than the EPIC group. The EPIC group showed a significantly higher postoperative mortality rate than the HIPEC group. Operation time (odds ratio [OR] 1.01; 95% confidence interval [CI] 1.01-1.02; p < 0.001), bowel anastomosis (OR 7.25; 95% CI 1.16-45.2; p = 0.034), neoadjuvant chemotherapy (OR 7.62; 95% CI 1.85-31.4; p = 0.005), and EPIC (OR 8.76; 95% CI 2.16-35.5; p = 0.002) were independent risk factors for major surgical complications. No association was observed between intraperitoneal chemotherapy type and major hematologic toxicity, overall survival, progression-free survival, or peritoneal progression-free survival. CONCLUSIONS: EPIC was a risk factor for major surgical complications. Survival outcomes were similar between the two types of intraperitoneal chemotherapy.

Biopsychosocial Late Effects After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastases from Colorectal and Appendiceal Cancer: A National Prospective Cohort Study.

BACKGROUND: Colorectal cancer with peritoneal metastases can be treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Treatment may result in biopsychosocial late effects (LEs). We explored the frequency and severity of the following biopsychosocial LEs: anxiety, depression, fear of cancer recurrence (FCR), insomnia, fatigue, cognitive impairment, and pain, and evaluated their impact on quality of life (QoL). METHOD: This was a national prospective cohort study screening for LEs during the period January 2021-May 2023. Patients completed the following questionnaires: General Anxiety Disorder-7, Patient Health Questionnaire-9, FCR Inventory-Short Form, Insomnia Severity Index, Functional Assessment of Chronic Illness Therapy-Fatigue, cognitive impairment (six items from the European Organisation for Research and Treatment of Cancer Item Library), and the Rectal Cancer Pain Score. Preregistration was completed at ClinicalTrials.gov (NCT04956107). RESULT: In total, 99 patients were included. The mean age was 61 years and 57% were women. At 3 months after surgery, the frequent LEs were fatigue (72%), FCR (58%), and pain (48%), and at 12 months after surgery, the frequent LEs were FCR (65%), fatigue (40%), and insomnia (33%). More than half of the patients (54%) reported at least two LEs after 12 months. Patients with moderate-to-severe LEs reported a lower QoL than patients with no/mild LEs. Patients with no/mild LEs had a similar QoL as the Danish norm population. CONCLUSION: Biopsychosocial LEs were prevalent. The QoL of patients reporting LEs in the worst severity categories was negatively impacted. Screening and treatment for these LEs should be a focus in cancer survivor follow-up.

Improved Postoperative Pain Management Outcomes After Implementation of Enhanced Recovery After Surgery (ERAS) Protocol for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS-HIPEC).

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for patients with peritoneal carcinomatosis is promising but has potential for significant morbidity and prolonged hospitalization. Enhanced Recovery After Surgery (ERAS) is a standardized protocol designed to optimize perioperative care. This study describes trends in epidural and opioid use after implementing ERAS for CRS-HIPEC at a tertiary academic center. METHODS: A retrospective analysis of patients undergoing CRS-HIPEC from January 2020 to September 2023 was conducted. ERAS was implemented in February 2022. Medication and outcomes data were compared before and after ERAS initiation. All opioids were converted to morphine milligram equivalents (MMEs). RESULTS: A total of 136 patients underwent CRS-HIPEC: 73 (54%) pre- and 63 (46%) post-ERAS. Epidural usage increased from 63% pre-ERAS to 87% post-ERAS (p = 0.001). Compared with those without epidurals, patients with epidurals had decreased total 7-day oral and intravenous (IV) opioid requirements (45 MME vs. 316 MME; p < 0.001). There was no difference in 7-day opioid totals between pre- and post-ERAS groups. After ERAS, more patients achieved early ambulation (83% vs. 53%; p < 0.001), early diet initiation (81% vs. 25%; p < 0.001), and early return of bowel function (86% vs. 67%; p = 0.012). CONCLUSIONS: ERAS implementation for CRS-HIPEC was associated with increased epidural use, decreased oral and IV opioid use, and earlier bowel function return. Our study demonstrates that epidural analgesia provides adequate pain control while significantly decreasing oral and IV opioid use, which may promote gastrointestinal recovery postoperatively. These findings support the implementation of an ERAS protocol for effective pain management in patients undergoing CRS-HIPEC.

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.

Ovarian cancer cells regulate their mitochondrial content and high mitochondrial content is associated with a poor prognosis.

Most cancer patients ultimately die from the consequences of distant metastases. As metastasis formation consumes energy mitochondria play an important role during this process as they are the most important cellular organelle to synthesise the energy rich substrate ATP, which provides the necessary energy to enable distant metastasis formation. However, mitochondria are also important for the execution of apoptosis, a process which limits metastasis formation. We therefore wanted to investigate the mitochondrial content in ovarian cancer cells and link its presence to the patient's prognosis in order to analyse which of the two opposing functions of mitochondria dominates during the malignant progression of ovarian cancer. Monoclonal antibodies directed against different mitochondrial specific proteins, namely heat shock proteins 60 (HSP60), fumarase and succinic dehydrogenase, were used in immunohistochemistry in preliminary experiments to identify the antibody most suited to detect mitochondria in ovarian cancer cells in clinical tissue samples. The clearest staining pattern, which even delineated individual mitochondria, was seen with the anti-HSP60 antibody, which was used for the subsequent clinical study staining primary ovarian cancers (n = 155), borderline tumours (n = 24) and recurrent ovarian cancers (n = 26). The staining results were semi-quantitatively scored into three groups according to their mitochondrial content: low (n = 26), intermediate (n = 50) and high (n = 84). Survival analysis showed that high mitochondrial content correlated with a statistically significant overall reduced survival rate In addition to the clinical tissue samples, mitochondrial content was analysed in ovarian cancer cells grown in vitro (cell lines: OVCAR8, SKOV3, OVCAR3 and COV644) and in vivo in severe combined immunodeficiency (SCID) mice.In in vivo grown SKOV3 and OVCAR8 cells, the number of mitochondria positive cells was markedly down-regulated compared to the in vitro grown cells indicating that mitochondrial number is subject to regulatory processes. As high mitochondrial content is associated with a poor prognosis, the provision of high energy substrates by the mitochondria seems to be more important for metastasis formation than the inhibition of apoptotic cell death, which is also mediated by mitochondria. In vivo and in vitro grown human ovarian cancer cells showed that the mitochondrial content is highly adaptable to the growth condition of the cancer cells.

Immunological impact of intraperitoneal and intravenous chemotherapy in ovarian cancer, translational analyses of the Phase 3 iPocc trial.

BACKGROUND: The iPocc trial, a randomized, global phase 3 study that compared intraperitoneal (IP) and intravenous (IV) carboplatin with dose-dense paclitaxel chemotherapy in epithelial ovarian cancer (EOC) patients, demonstrated improved progression-free survival in patients who received IP chemotherapy. The present study aimed to investigate the role of preexisting tumor immunity in the clinical outcomes of patients receiving IP chemotherapy. METHODS: This study involved analyzing patient data from the iPocc trial, selectively of those whose tumor specimens were preserved at the time of primary surgery. A total of 116 cases ((IP; n = 59), (IV; n = 57)) were subjected to microarray analysis. Single-sample gene set enrichment analyses were performed to evaluate the tumor immune microenvironment. RESULTS: Patients with enhanced tumor infiltration of T cells, natural killer (NK) cells, and cytotoxic lymphocytes in the IP group had a longer overall survival (OS) than those in the IV group, but not in the group with low infiltration. IP therapy improved the OS of patients with high expression of immune-related genes such as CD8A and FOXP3. In patients' subdivided into "immune Hot" and "immune Cold" groups based on hierarchical clustering analysis using four parameters representing "Innate immunity," "T cells," "IFNG response" and "Inhibitory molecules," IP therapy significantly improved prognosis in the "immune Hot" group, but not in the "immune Cold" group compared to that of IV therapy. CONCLUSIONS: IP chemotherapy enhances the survival rates of patients with EOC with an immune-Hot phenotype in the tumor microenvironment prior to treatment. (Japan Registry of Clinical Trials number, jRCTs031180141.).

Intraperitoneal immunotherapy with denileukin diftitox (ONTAK) in recurrent refractory ovarian cancer.

BACKGROUND: Denileukin diftitox (ONTAK) is a diphtheria/IL-2R fusion protein able to deplete regulatory T cells in peripheral blood. Regulatory T cells in the local immune microenvironment have been shown to be associated with poor prognosis in ovarian cancer. This study examined whether denileukin diftitox (ONTAK) could be safely administered intraperitoneal in patients with advanced refractory ovarian cancer and assessed its effects on regulatory T cells and tumor associated cytokines in ascites and peripheral blood. PATIENTS AND METHODS: A phase I dose escalation study of intraperitoneal denileukin diftitox (ONTAK) enrolled 10 patients with advanced, refractory ovarian carcinoma at 3 doses (5 µg/kg, 15 µg/kg, and 25 µg/kg). Serial CA-125 measurements assessed clinical response. Regulatory T cells were quantified using RT-PCR and cytokine levels measured by Luminex. RESULTS: The maximum tolerated dose was 15 µg/kg with a dose limiting toxicity observed in 1 out of 6 patients in the expansion group. The majority of adverse events were transient grades 1-2. One patient treated at the 25 µg/kg dose experienced cytokine storm with prolonged hospitalization. 3 patients had decreases in CA-125 after treatment but none met criteria for partial response. Treatment with denileukin diftitox (ONTAK) decreased regulatory T cells in peripheral blood and ascites. Treated patients did not show any significant changes in IL-8, TGF-ß, sIL2Ra in ascites or peripheral blood. CONCLUSIONS: Denileukin diftitox (ONTAK) can be safely administered intraperitoneally to recurrent refractory ovarian cancer patients. Regulatory T cells were reduced in ascites and peripheral blood, but there were no significant changes in cytokine levels. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov # NCT00357448.

Determining the maximum tolerated dose of paclitaxel combined with fixed dose of cisplatin for hyperthermic intraperitoneal chemotherapy in ovarian cancer: A multicenter phase I trial.

OBJECTIVE: To determine the maximum tolerated dose (MTD) of paclitaxel combined with a fixed dose of cisplatin (75 mg/m2) delivered via hyperthermic intraperitoneal chemotherapy (HIPEC) to patients with ovarian cancer. METHODS: This multicenter Phase I trial employed a Bayesian Optimal Interval (BOIN) design. The MTD was determined to have a target dose-limiting toxicity (DLT) rate of 25%. The starting dose was 175 mg/m2. The Data and Safety Monitoring Board made decisions regarding dose escalation or de-escalation in increments of 25 mg/m2 for subsequent patient cohorts, up to a maximum sample size of 30 or 12 patients treated at a given dose. RESULTS: Twenty-one patients participated in this study. Among the three evaluable patients who received 150 mg/m2 paclitaxel, no DLTs were observed. Among the 12 evaluable patients who received 175 mg/m2 paclitaxel, two reported DLTs: one had grade 4 neutropenia and one had grade 4 anemia, neutropenia, and leukopenia. Four of the six evaluable patients who received 200 mg/m2 paclitaxel reported DLTs: one patient had grade 4 diarrhea, one had grade 3 kidney injury, and two had grade 4 anemia. The isotonic estimate of the DLT rate in the 175 mg/m2 dose group was 0.17 (95% confidence interval, 0.02-0.42), and this dose was selected as the MTD. CONCLUSION: Paclitaxel, when combined with a fixed dose of cisplatin (75 mg/m2), can be safely administered intraperitoneally at a dose of 175 mg/m2 in patients with ovarian cancer who received HIPEC (43 °C, 90 min) following cytoreductive surgery.

Omission of intraoperative drain placement during robotic partial nephrectomy and robotic radical prostatectomy is safe: an analysis of 18,000 patients.

PURPOSE: Placement of a drain during robotic assisted partial nephrectomy (RAPN) and robotic assisted radical prostatectomy (RARP) is standard practice for many urologists and can aid in assessment and management of complications such as urine leak, lymphocele, or bleeding. However, drain placement can cause discomfort and delay patient discharge, with questionable benefit. We aim to assess the correlation between drain placement with post operative complications. METHODS: The NSQIP targeted database was queried for patients who underwent RAPN or RARP from 2019 to 2021. Our primary outcomes included 30-day complication rates stratified by intraoperative drain placement. Secondary outcomes included procedure-specific complications, length of stay (LOS), and readmissions. Multivariable regression analyses, with Bonferroni correction, were performed for each post-operative complication. RESULTS: We identified 4738 and 13,948 patients who underwent RAPN and RARP, respectively. Drains were not placed in 2258 (47.7%) and 6700 (48%) patients, respectively. On adjusted multivariable analysis in the RAPN cohort, omission of drain placement was associated with decreased LOS (ß -0.45; 99.58% CI [-0.59, -0.32]) but no difference in overall complication rates. After adjusted analysis in the RARP cohort, omission of drain placement was associated with decreased risk of any complication (OR 0.73 [0.62-0.87]), infectious complication (OR 0.66 [0.49-0.89]), and LOS (ß -0.30 [-0.37, -0.24]). CONCLUSIONS: Using a large contemporary database, this study demonstrates that omission of drains during RAPN and RARP was safe without increased risk of postoperative complications. Despite inherent selection bias in this cohort, our data suggests that routine drain placement is not necessary for these procedures.

Management of Peritoneal Surface Malignancies in Saudi Arabia: An Update.

Peritoneal surface malignancies (PSM) are aggressive and associated with poor prognosis. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) have been used to treat PSM since 1990. In Saudi Arabia, the first HIPEC and pressurized intraperitoneal aerosol chemotherapy (PIPAC) were performed in 2008 and 2019, respectively. With increasing incidences of PSM in Saudi Arabia, the demand for such procedures has grown. This article outlines the status of PSM management in Saudi Arabia and its prospects.