Pseudomyxoma peritonei (PMP) is a rare intra-abdominal malignancy characterized by diffuse dissemination of mucinous tumor cells, leading to mucinous ascites. Accurate diagnosis is crucial for appropriate management. This report presents a case of a 55-year-old Lebanese male farmer initially misdiagnosed with liver cirrhosis who presented with progressive abdominal distension refractory to diuretics and dietary modifications. Paracentesis revealed a mucinous exudate, with subsequent clinical and histopathological examination confirming PMP. The patient was referred for further evaluation at a specialized center equipped for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). This case highlights the diagnostic challenges of PMP due to its non-specific presentation, emphasizing the importance of prompt and accurate diagnosis to facilitate optimal therapeutic intervention.

BACKGROUND: In gastric cancer, peritoneal metastasis is the most common form of metastasis and leads to dismal prognosis. We aimed to evaluate the safety and efficacy of combining perioperative intraperitoneal (IP) plus systemic chemotherapy, cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with gastric cancer with limited peritoneal metastasis or even after reducing peritoneal tumor burden by upfront IP chemotherapy.
METHODS: Patients were enrolled in phase Ib in a 3 + 3 dose escalation of IP paclitaxel plus a fixed dose of IP cisplatin and oral S-1. In phase II, patients were managed according to the peritoneal cancer index (PCI) by diagnostic laparoscopy. For patients with a PCI of >12, upfront IP and systemic chemotherapy were given. Patients with a PCI of ≤12 or reduced to ≤12 after upfront chemotherapy underwent CRS with HIPEC. The primary endpoints were safety and the recommended phase II dose (RP2D) confirmation for phase Ib and the 1-year overall survival rate for phase II.
RESULTS: The RP2D was defined as IP 175 mg/m2 paclitaxel and 60 mg/m2 cisplatin and oral 70 mg/m2/day S-1 for 14 days. A total of 22 patients were included. After CRS with HIPEC, there were no grade 3 or higher complications. The median hospital stay was 7 days (range, 6-11). The median overall and progression-free survival were 27.3 months (95% CI, 14.4 to not estimable) and 12.6 months (95% CI, 7.7-14.5), respectively. One-year overall and progression-free survival rates were 81.0% (95% CI, 65.8-99.6) and 54.5% (95% CI, 37.2-79.9), respectively.
CONCLUSIONS: A combination of IP plus systemic chemotherapy, CRS, and HIPEC was safe and resulted in good survival outcomes.

Ovarian cancer, notable for its severe prognosis among gynecologic cancers, has seen substantial progress in treatment approaches recently. Enhanced protocols in chemotherapy and the introduction of poly (ADP-ribose) polymerase (PARP) inhibitors for maintenance therapy have markedly improved outcomes for patients with specific genetic profiles, such as those positive for BRCA mutations or exhibiting homologous recombination deficiency (HRD). Additionally, the method of intraperitoneal chemotherapy administration has emerged as a valuable alternative to traditional transvenous routes, showing promise for wider clinical adoption. The field of surgery has also evolved, with increasing exploration into the benefits and feasibility of laparoscopic methods over more invasive traditional surgeries, aiming for complete tumor removal but with reduced patient impact. The hereditary nature of ovarian cancer underscores the importance of genetic testing, which has become integral in tailoring treatment strategies, particularly in determining suitability for PARP inhibitors. The formation of the East Asian Gynecologic Oncology Trial Group (EAGOT) aims to optimize treatment across Japan, Korea, China, and Taiwan. The ovarian cancer committee of EAGOT shared the current policies, focusing on 5 topics: 1) strategies for maintenance therapy after initial surgery and chemotherapy, 2) drug regimens for platinum-sensitive and platinum-resistant recurrence, 3) intraperitoneal chemotherapy, 4) laparoscopic surgery as an alternative to laparotomy, and 5) current status of genetic testing (BRCA, HRD, and panel tests) for ovarian cancer and its prospects. EAGOT\'s multi-national trials aim to harmonize these evolving treatment strategies, ensuring that the latest and most effective protocols are accessible across the region, thereby significantly impacting patient outcomes in East Asia.

Peritoneal metastasis is a common finding in patients with advanced gastric cancer. Beyond systemic chemotherapy, additive local treatments such as cytoreductive surgery and intraperitoneal chemotherapy are considered an inherent part of different multimodal treatment concepts for selected patients with peritoneal metastatic gastric cancer. This review article discusses the role of cytoreductive surgery (CRS) and intraperitoneal chemotherapy, including HIPEC, NIPS, and PIPAC, as additive therapeutic options with curative and palliative intent.

BACKGROUND: The knowledge of BRCA status offers a chance to evaluate the role of the intraperitoneal route in patients selected by biomolecular profiles after primary cytoreduction surgery in advanced ovarian cancer.
METHODS: We performed a retrospective, multicenter study to assess oncological outcomes depending on adjuvant treatment (intraperitoneal [IP] vs intravenous [IV]) and BRCA status (BRCA1/2 mutated vs. BRCA wild type [WT]). The primary endpoint was to determine progression-free survival. The secondary objectives were overall survival and toxicity.
RESULTS: A total of 288 women from eight centers were included: 177 in the IP arm and 111 in the IV arm, grouped into four arms according to BRCA1/2 status. Significantly better PFS was observed in BRCA1/2-mutated patients with IP chemotherapy (HR: 0.35; 95% CI, 0.16-0.75, p = 0.007), which was not present in BRCA1/2-mutated patients with IV chemotherapy (HR: 0.65; 95% CI, 0.37-1.12, p = 0.14). Significantly better OS was also observed in IP chemotherapy (HR: 0.17; 95% CI, 0.06-043, p < 0.0001), but was not present in IV chemotherapy in relation with BRCA mutation (HR: 0.52; 95% CI, 0.22-1.27, p = 0.15). For BRCA WT patients, worse survival was observed regardless of the adjuvant route used. The IP route was more toxic compared to the IV route, but toxicity was equivalent at the long-term follow-up.
CONCLUSIONS: This retrospective study suggests that BRCA status can help to offer an individualized, systematic treatment after optimal primary surgery for advanced ovarian cancer, but is limited by the small sample size. Prospective trials are essential to confirm these results.

OBJECTIVE: Despite advances in systemic therapy, outcomes of patients with gastric cancer (GC) peritoneal carcinomatosis (PC) remain poor, in part because of poor penetrance of systemic therapy into peritoneal metastasis due to the plasma-peritoneal barrier and anarchic intra-tumoral circulation. Hence, regional treatment approach with administration of chemotherapy directly into the peritoneal cavity (intraperitoneal, IP) under various conditions, combined with or without cytoreductive surgery (CRS) has remained an area of significant research interest. The purpose of this review is to provide high-level evidence for regional treatment approaches in the management of GCPC with limited peritoneal disease.
METHODS: A review of the current literature and ongoing clinical trials for regional IP therapies for GCPC was performed. Studies included in this review comprise of phase III randomized controlled trials, non-randomized phase II studies, high-impact retrospective studies, and active ongoing clinical trials for each available IP modality.
RESULTS: The three common IP approaches are heated intraperitoneal chemotherapy (HIPEC), normothermic intraperitoneal chemotherapy (NIPEC) and more recently introduced, pressurized intraperitoneal aerosolized chemotherapy (PIPAC). These IP approaches have been combined with systemic therapy and/or CRS with varying degrees of promising results, demonstrating evidence of improvements in survival rates and peritoneal disease control. Patient selection, optimization of systemic therapy, and completeness of cytoreduction have emerged as major factors influencing the design of contemporary and ongoing trials.
CONCLUSIONS: IP chemotherapy has a clear role in the management of patients with GCPC, and when combined with CRS in appropriately selected patients has the potential to significantly improve survival. Ongoing and upcoming IP therapy clinical trials hold great promise to shape the treatment paradigm for GCPC.

In our clinical practice, we have shifted away from the use of adjuvant normothermic intraperitoneal (IP) chemotherapy, particularly following the publication of GOG 252. Our decision is rooted in the accumulating evidence indicating a lack of demonstrable superiority, alongside the recognized toxicities and logistical challenges associated with its administration. This strategic departure is also influenced by the rising utilization of maintenance therapies such as bevacizumab and PARP inhibitors, which present viable alternatives for improving patient outcomes. Our utilization of hyperthermic IP chemotherapy (HIPEC) is currently reserved for a specific cohort of patients, mirroring the patient population studied in the OVHIPEC-1 trial. Specifically, our HIPEC protocol applies to patients presenting with newly diagnosed stage IIIC high-grade epithelial ovarian cancer who are deemed ineligible for primary debulking surgery. Patients must exhibit at least stable disease with neoadjuvant platinum-based chemotherapy, maintain a favorable performance status (ECOG score 0-1), possess good nutritional reserves (with no evidence of protein-calorie malnutrition and an albumin level exceeding 3.5), and not have chronic kidney disease. When HIPEC is planned, it is administered at the time of interval debulking surgery, contingent upon the attainment of optimal surgical outcomes (< 1 cm of residual disease). Our HIPEC protocol adheres to the original OVHIPEC-1 trial guidelines, employing cisplatin at a dosage of 100 mg/m2. We administer at least two antiemetics, antihistamines, and sodium thiosulfate to mitigate known side effects. Postoperatively, patients are admitted to the general surgical floor, reserving the intensive care unit for those in critical condition. We follow Enhanced Recovery After Surgery principles, incorporating early ambulation and feeding into our postoperative care strategy. We have encountered encouraging results with this approach, with most patients having largely uncomplicated postoperative courses and resuming adjuvant chemotherapy within 3 to 4 weeks of surgery.

Since the latest practice guidelines for ovarian cancer were developed by the Korean Society of Gynecologic Oncology (KSGO) in 2021, many studies have examined the efficacy and safety of various treatments for epithelial ovarian cancer (EOC). Therefore, the need to develop recommendations for EOC treatments has been raised. This study searched the literature using 4 key items and the Population, Intervention, Comparison, and Outcome: the efficacy and safety of poly-ADP ribose polymerase inhibitors in newly diagnosed advanced EOC; the efficacy and safety of intraperitoneal plus intravenous chemotherapy in optimally debulked advanced EOC; the efficacy and safety of secondary cytoreductive surgery in platinum-sensitive recurrent ovarian cancer; and the efficacy and safety of the addition of bevacizumab to platinum-based chemotherapy in first platinum-sensitive recurrent EOC patients who received prior bevacizumab. The evidence for these recommendations, according to each key question, was evaluated using a systematic review and meta-analysis. The committee of ovarian cancer of the KSGO developed updated guidelines for treatments of EOC.

BACKGROUND: Ovarian cancer is the gynaecological malignancy with the highest mortality and diagnosis often occurs in its advanced stages. Standard treatment in these cases is based on complete cytoreductive surgery with adjuvant intravenous chemotherapy. Other types of treatment are being evaluated to improve the prognosis of these patients, including intraperitoneal chemotherapy and antiangiogenic therapy. These may improve survival or time to relapse in addition to intravenous chemotherapy.
OBJECTIVE: The aim of this meta-analysis is to determine whether treatment with intravenous chemotherapy remains the gold standard, or whether the addition of intraperitoneal chemotherapy has a benefit in overall survival (OS) and disease-free interval (DFS).
METHODS: A literature search was carried out in Pubmed and Cochrane, selecting clinical studies and systematic reviews published in the last 10 years. Statistical analysis was performed using the hazard ratio measure in the RevMan tool.
RESULTS: Intraperitoneal chemotherapy shows a benefit in OS and DFS compared with standard intravenous chemotherapy. The significant differences in OS (HR: 0.81 CI 95% 0.74-0.88) and in DFS (HR: 0.81 CI 95% 0.75-0.87) are statistically significant (p < 0.00001). There were no clinical differences in toxicity and side-effects.
CONCLUSIONS: Intraperitoneal chemotherapy is an option that improves OS and DFS without significant toxicity regarding the use of intravenous chemotherapy alone. However, prospective studies are needed to determine the optimal dose and treatment regimen that will maintain the benefits while minimising side effects and toxicity and the profile of patients who will benefit most from this treatment.

Cytoreductive surgery (CRS), combined with hyperthermic intraperitoneal chemotherapy, has significantly improved survival outcomes in patients with peritoneal carcinomatosis from colorectal cancer (CRC). Regorafenib is an oral agent administered in patients with refractory metastatic CRC. Our aim was to investigate the outcomes of intraperitoneal administration of regorafenib for intraperitoneal chemotherapy (IPEC) or/and CRS in a rat model of colorectal peritoneal metastases regarding immunology and peritoneal cytology. A total of 24 rats were included. Twenty-eight days after carcinogenesis induction, rats were randomized into following groups: group A: control group; group B: CRS only; group C: IPEC only; and group D: CRS + IPEC. On day 56 after carcinogenesis, euthanasia and laparotomy were performed. Serum levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) as well as peritoneal cytology were investigated. Groups B and D had statistically significant lower mean levels of IL-6 and TNF-α compared to groups A and C, but there was no significant difference between them. Both B and D groups presented a statistically significant difference regarding the rate of negative peritoneal cytology, when compared to the control group, but not to group C. In conclusion, regorafenib-based IPEC, combined with CRS, may constitute a promising tool against peritoneal carcinomatosis by altering the tumor microenvironment.