Background PIPAC is a recent approach for intraperitoneal chemotherapy with promising results for patients with peritoneal carcinomatosis (PC). We aimed to evaluate the postoperative outcome of PIPAC in patients with non-resectable PC during our initial experience of the technique. Methods All patients who underwent PIPAC for non-resectable PC in three centers were analyzed regarding postoperative outcomes. Results Seventy-three patients underwent 164 PIPAC. PC was from colorectal, gastric, ovarian, malignant mesothelioma, pseudomyxoma peritonei or other origins in 20, 26, 13, 8, 1 and 5 patients respectively. Forty-five (62%), 31 (42%), 8 (11%), 6 (8%), 1 (1%) patients underwent a second, third, fourth, fifth, and sixth PIPAC respectively. At the time of the first PIPAC, the median PCI was 17 (1–39), 57 patients presented with symptomatic PC (pain: 33; ascites: 35; transit disorder like diarrhea and constipation: 11). PCI improved in 64.5% of patients, 63.5% of patients presented with complete disappearance of symptoms. Major complications occurred as the outcome of 16 PIPAC (9.7%) and 5 (6.8%) patients died within 30 days of the PIPAC procedure. Rate of mortality and major complications 40% and 62% respectively occurred in first 20 treated patients. For 64 (88%) patients, systemic chemotherapy was associated with PIPAC and could be administered after PIPAC with a median delay of 14 days (2–28). Conclusions Implementing a PIPAC program in association with systemic chemotherapy is feasible and is associated with a risk of postoperative morbidity, even in teams highly experienced in PC management and requires a learning curve in patient selection.

Multicentric initial experience with the use of the pressurized intraperitoneal aerosol chemotherapy (PIPAC) in the management of unresectable peritoneal carcinomatosis.

Background
The aim was to determine the incremental value of MRI compared with CT in the preoperative estimation of the peritoneal carcinomatosis index (PCI).

Methods
CT and MRI examinations of patients with peritoneal carcinomatosis were evaluated. CT images were first analysed by two observers who determined a first PCI (PCICT). Then, the two observers reviewed MRI examinations in combination with CT and determined a second PCI (PCICT + MRI). The sensitivity and negative predictive value of the two imaging sets were determined using surgery as a reference standard (PCIRef).

Results
CT plus MRI was more accurate in predicting the surgical PCI than CT alone. The absolute difference between PCICT + MRI and PCIRef was lower than that between PCICT and PCIRef (mean(s.d.) 3·96(4·10) versus 4·89(4·73); P = 0·010). The number of true-positive findings increased from 106 to 125 for reader 1 and from 117 to 132 for reader 2 with the adjunct of MRI. For both readers, an increased sensitivity was obtained when both MRI and CT were used (from 63 to 81 per cent for reader 1; from 44 to 81 per cent for reader 2). The increase in sensitivity was greater for patients with a moderate volume of disease.

Conclusion
The combination of CT and MRI improved the preoperative estimation of PCI compared with CT alone.

Evaluation of the peritoneal carcinomatosis index with CT and MRI.

Background Effective tumor debulking is a major factor associated with a favorable prognosis in patients with advanced ovarian cancer (AOC). However, FIGO staging fails to take full account of the extent of the disease in the peritoneum, making it difficult to plan appropriate surgical treatment. In contrast, the peritoneal cancer index (PCI) can provide more detailed information about peritoneal spread. Method We evaluated the prognostic value of PCI and its association with clinicopathological features in patients with AOC. Data for 80 patients with AOC who underwent primary debulking surgery were analyzed retrospectively. PCI scores of 0–39 were calculated based on the sizes of lesions in 13 abdominopelvic regions, and patients were classified into three categories with scores of 1–10, 11–20, and >20, respectively. Clinicopathological features, including the presence of residual tumor after surgery and the incidence of postoperative complications, were assessed in relation to PCI score. Results PCI was significantly associated with suboptimal surgery and postoperative complications, as well as with preoperative CA125, ascites, prolonged surgery, FIGO stage, positive aortic lymph nodes, prolonged hospitalization, and number of visceral resections. Overall and disease-free survival was also associated with PCI, with an optimal cut-off value of 15. Multivariate analysis identified age, residual tumor, and PCI as independent prognostic factors for survival. A PCI >10 is positively associated with a poor prognosis in patients with AOC. Conclusion Given the importance of effective tumor debulking, PCI may provide important information for surgical planning in patients with AOC.

Prognostic value of peritoneal cancer index in primary advanced ovarian cancer

Background PIPAC is a recent approach with promising results for patients with peritoneal metastasis (PM). We aimed to evaluate survival and postoperative outcome of patients with unresectable PM from gastric origin treated with chemotherapy and PIPAC. Methods A retrospective analysis of a prospective maintained PIPAC database was queried for all patients diagnosed with unresectable PM from gastric cancer who underwent PIPAC before 2018. PIPAC with Cisplatin 7.5 mg/m2 and doxorubicin 1.5 mg/m2 were given for 30 min at 6-week intervals. Outcome criteria were overall survival and adverse events according to (CTCAE) version4.0. Results One hundred Sixty-three PIPAC were done in 42 consecutive patients. Twenty-two (52%) of the patients were female. Signet-ring cells were observed in 33/42 patients (78.6%). At the first PIPAC, median age was 51.5 years (32–74). Median PCI was 17 (1–39). Twenty (47.6%) patients underwent more than 2 lines of pre-PIPAC chemotherapy. All patients had systemic chemotherapy alternating with PIPAC. Median consecutive PIPAC procedures were 3 (1–12). Overall and major complications (CTCAE - III, IV) occurred in 10 (6.1%) and 5 procedures (3.1%), respectively. Two patients (4.7%) died within 30 days of a PIPAC procedure, one related to small bowel obstruction and a pulmonary embolism for the other. Overall Survival was 19.1 months. Six (14.3%) patients became resectable during treatment and underwent curative intent CRS and HIPEC. Conclusions PIPAC with low-dose cisplatin and doxorubicin is safe and feasible in association with systemic chemotherapy for gastric PM. Survival data are encouraging and justify further clinical studies in this indication.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) for unresectable peritoneal metastasis from gastric cancer.

MR imaging provides considerable advantages in the evaluation of patients with peritoneal metastases. A standardized peritoneal MRI protocol, including diffusion-weighted and gadolinium-enhanced sequences, allows an efficient exploration of small peritoneal tumors that are often missed on other imaging tests. In experienced hands, a dedicated reading allows producing a quantitative and qualitative evaluation of lesional localization to better assist surgeons in the selection of candidates for curative surgery by evaluating the possibility of complete resection, and to plan the surgical procedure. Based on a close collaboration between oncologic surgeon and radiologist, MRI provides a powerful tool for accurate preoperative imaging in patients being considered for curative surgery but also in their surveillance to detect an early recurrence.

Peritoneal MRI in patients undergoing cytoreductive surgery and HIPEC: History, clinical applications, and implementation.

Based on the importance of assessing the true extent of peritoneal disease, PeRitOneal MalIgnancy Stage Evaluation (PROMISE) internet application (www.e-promise.org) has been developed to facilitate tabulation and automatically calculate surgically validated peritoneal cancer index (PCI), and other surgically validated scores as Gilly score, simplified peritoneal cancer index (SPCI), Fagotti and Fagotti-modified scores. This application offers computer-assistance to produce simple, quick but precise and standardized pre, intra and postoperative reports of the extent of peritoneal metastases and may help specialized and non-specialized institutions in their current practice but also facilitate research and multicentre studies on peritoneal surface malignancies.

G. Desolneux

Papers

A new internet tool to report peritoneal malignancy extent. PeRitOneal MalIgnancy Stage Evaluation (PROMISE) application