Peritoneal Metastasis Research Articles

Exploring membranous NECTIN-4 expression patterns and enfortumab vedotin response in prostate cancer.

Antibody-drug conjugates (ADCs) represent a novel type of targeted cancer therapy combining the specificity of monoclonal antibodies with the cytotoxicity of conventional chemotherapy. Recently, ADCs have demonstrated practice-changing efficacy across diverse solid cancers. The anti-NECTIN-4 ADC enfortumab vedotin (EV) has just been approved for patients with urothelial cancer and is currently under investigation for patients with castration-resistant prostate cancer (CRPC e.g. Phase II ENCORE trial). Our objective was to evaluate the efficacy of EV in established prostate cancer (PCa) cell lines and to examine the membranous NECTIN-4 expression in primary tumours (PRIM) and distant metastases (MET). NECTIN-4 was heterogeneously expressed in the panel of PCa cell lines. EV led to growth inhibition in NECTIN-4 expressing PCa cells (22Rv1 and LNCaP), whereas the NECTIN-4-negative PC-3 cells were significantly less responsive to EV, emphasizing the dependence of EV response on its target expression. Immunohistochemical staining revealed moderate membranous NECTIN-4 expression only in a small subgroup of CRPC patients with lung and peritoneal MET [n = 3/22 with H-score ≥100, median H-score 140 (IQR 130-150)], while 100% of PRIM (n = 48/48) and 86.4% of common MET sites (n = 19/22), including lymph node, bone and liver MET, were NECTIN-4 negative. In summary, EV may be effective in NECTIN-4-positive PCa. However, our findings demonstrate that the tumoural NECTIN-4 expression is predominantly low in metastatic PCa, which suggests that EV may only be effective in a biomarker-stratified subgroup.

Circulating Exosomal MicroRNA Signature Predicts Peritoneal Metastasis in Patients with Advanced Gastric Cancer.

Despite a radical operation, about half of gastric cancer (GC) patients with advanced GC experience peritoneal metastasis (PM), and the patients with PM have a poor prognosis. However, because staging laparoscopy was a highly invasive procedure for patients, identification of PM using a liquid biopsy can be useful for patients with GC. This study analyzed two genome-wide miRNA expression profiling datasets (GSE164174 and TCGA). The study prioritized biomarkers in pretreatment plasma specimens from clinical training and validation cohorts of patients with GC. The authors developed an integrated exosomal miRNA panel and established a risk-stratification model, which was combined with the miRNA panel and currently used tumor markers (CEA, CA19-9, CA125, and CA72-4 levels). The comprehensive discovery effort identified a four-miRNA panel that robustly predicted the metastasis with excellent accuracy in the TCGA dataset (area under the curve [AUC] 0.86). A circulating exosomal miRNA panel was established successfully with remarkable diagnostic accuracy in the clinical training (AUC 0.85) and validation (AUC 0.86) cohorts. Moreover, the predictive accuracy of the panel was significantly superior to that of conventional clinical factors (P < 0.01), and the risk-stratification model was dramatically superior to the panel and currently used clinical factors for predicting PM (AUC 0.94; univariate: odds ratio [OR] 77.00 [P < 0.01]; multivariate OR 57.71 [P = 0.01]). The novel risk-stratification model for predicting PM has potential for clinical translation as a liquid biopsy assay for patients with GC. The study findings highlight the potential clinical impact of the model for improved selection and management of patients with GC.

Sulfatide imaging identifies tumor cells in colorectal cancer peritoneal metastases

Even with systemic chemotherapy, cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy (HIPEC), peritoneal metastases (PM) remain a common site of disease progression for colorectal cancer (CRC) and are frequently associated with a poor prognosis. The mass spectrometry (MS) method known as Matrix-Assisted Laser Desorption/Ionization – Time of Flight (MALDI-TOF) is frequently used in medicine to identify structural compounds and biomarkers. It has been demonstrated that lipids are crucial in mediating the aggressive growth of tumors. In order to investigate the lipid profiles, particularly with regard to histological distribution, we used MALDI-TOF MS (MALDI-MS) and MALDI-TOF imaging MS (MALDI-IMS) on patient-derived tumor organoids (PDOs) and PM clinical samples. According to the MALDI-IMS research shown here, the predominant lipid signature of PDOs in PM tissues, glycosphingolipid (GSL) sulfates or sulfatides, or STs, is unique to the areas containing tumor cells and absent from the surrounding stromal compartments. Bioactive lipids are derived from arachidonic acid (AA), and AA-containing phosphatidylinositol (PI), or PI (18:0–20:4), is shown to be highly expressed in the stromal components. On the other hand, the tumor components contained a higher abundance of PI species with shorter and more saturated acyl chains (C34 and C36 carbons). The cellular subversion of PI and ST species may alter in ways that promote the growth, aggressiveness, and metastasis of tumor cells. Together, these findings suggest that the GSL/ST metabolic programming of PM may contain novel therapeutic targets to impede or halt PM progression.

Transcriptomics-based liquid biopsy panel for early non-invasive identification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer

BackgroundThis study aimed to develop a novel six-gene expression biomarker panel to enhance the early detection and risk stratification of peritoneal recurrence and micrometastasis in locally advanced gastric cancer (LAGC).MethodsWe used genome-wide transcriptome profiling and rigorous bioinformatics to identify a six-gene expression biomarker panel. This panel was validated across multiple clinical cohorts using both tissue and liquid biopsy samples to predict peritoneal recurrence and micrometastasis in patients with LAGC.ResultsThrough genome-wide expression profiling, we identified six mRNAs and developed a risk prediction model using 196 samples from a surgical specimen training cohort. This model, incorporating a 6-mRNA panel with clinical features, demonstrated high predictive accuracy for peritoneal recurrence in gastric cancer patients, with an AUC of 0.966 (95% CI: 0.944–0.988). Transitioning from invasive surgical or endoscopic biopsy to noninvasive liquid biopsy, the model retained its predictive efficacy (AUC = 0.963; 95% CI: 0.926–1.000). Additionally, the 6-mRNA panel effectively differentiated patients with or without peritoneal metastasis in 95 peripheral blood specimens (AUC = 0.970; 95% CI: 0.936–1.000) and identified peritoneal micrometastases with a high efficiency (AUC = 0.941; 95% CI: 0.874–1.000).ConclusionsOur study provides a novel gene expression biomarker panel that significantly enhances early detection of peritoneal recurrence and micrometastasis in patients with LAGC. The RSA model's predictive capability offers a promising tool for tailored treatment strategies, underscoring the importance of integrating molecular biomarkers with clinical parameters in precision oncology.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy in the Management of Colorectal Cancer with Peritoneal Metastasis: A Single-Center Cohort Study.

Multimodal treatment in peritoneal metastases (PM) from colorectal neoplasms may improve overall survival (OS). In this study, we reported our experience in using cytoreductive surgery (CRS) combined with intraperitoneal chemohyperthermia (HIPEC) for the treatment of peritoneal metastases (PM) from colorectal neoplasms. The first aim was to evaluate the overall survival of these patients. Furthermore, using the results of the Prodige 7 Trial and incorporating them with the entropy balance statistical tool, we generated a pseudopopulation on which to test the use of CRS alone. We performed a retrospective analysis based on a prospective database of all 55 patients treated with CRS + HIPEC between March 2004 and January 2023. The median OS was 47 months, with 1-, 3- and 5-year survival rates of 90.8%, 58.7% and 42.7%, respectively. There was no significant difference in the data in the pseudogroup generated with entropy balance. This finding confirms the critical role of complete cytoreduction in achieving the best OS for patients with PM. PCI > 6 seems to be the most important prognostic factor influencing OS. At present, CRS + HIPEC seems to be the therapeutic strategy that guarantees the best results in terms of OS for patients with relatively low PCI and in whom a CCS ≤ 1 can be achieved.

Tumor recurrence and survival prognosis in patients with advanced gastric cancer after radical resection with radiotherapy and chemotherapy.

Advanced gastric cancer is a common malignancy that is often diagnosed at an advanced stage and is still at risk of recurrence after radical surgical treatment. Chemoradiotherapy, as one of the important treatment methods for gastric cancer, is of great significance for improving the survival rate of patients. However, the tumor recurrence and survival prognosis of gastric cancer patients after radiotherapy and chemotherapy are still uncertain. To analyze the tumor recurrence after radical radiotherapy and chemotherapy for advanced gastric cancer and provide more in-depth guidance for clinicians. A retrospective analysis was performed on 171 patients with gastric cancer who received postoperative adjuvant radiotherapy and chemotherapy in our hospital from 2021 to 2023. The Kaplan-Meier method was used to calculate the recurrence rate and survival rate; the log-rank method was used to analyze the single-factor prognosis; and the Cox model was used to analyze the prognosis associated with multiple factors. The median follow-up time of the whole group was 63 months, and the follow-up rate was 93.6%. Stage II and III patients accounted for 31.0% and 66.7%, respectively. The incidences of Grade 3 and above acute gastrointestinal reactions and hematological adverse reactions were 8.8% and 9.9%, respectively. A total of 166 patients completed the entire chemoradiotherapy regimen, during which no adverse reaction-related deaths occurred. In terms of the recurrence pattern, 17 patients had local recurrence, 29 patients had distant metastasis, and 12 patients had peritoneal implantation metastasis. The 1-year, 3-year, and 5-year overall survival (OS) rates were 83.7%, 66.3%, and 60.0%, respectively. The 1-year, 3-year, and 5-year disease-free survival rates were 75.5%, 62.7%, and 56.5%, respectively. Multivariate analysis revealed that T stage, peripheral nerve invasion, and the lymph node metastasis rate (LNR) were independent prognostic factors for OS. Postoperative intensity-modulated radiotherapy combined with chemotherapy for gastric cancer treatment is well tolerated and has acceptable adverse effects, which is beneficial for local tumor control and can improve the long-term survival of patients. The LNR was an independent prognostic factor for OS. For patients with a high risk of local recurrence, postoperative adjuvant chemoradiation should be considered.

Intraperitoneal chemotherapy for colorectal cancer peritoneal metastasis

Peritoneal metastasis is one of the common site of colorectal cancer metastasis and associated with a poor prognosis. The core strategy for colorectal cancer peritoneal metastasis primarily revolves around a comprehensive treatment approach with cytoreductive surgery and systemic chemotherapy as the mainstay, supplemented by intraperitoneal chemotherapy. As an important supplement to treatment, intraperitoneal chemotherapy has broad application prospects. The main modalities are hyperthermic intraperitoneal chemotherapy (HIPEC), neoadjuvant intraperitoneal and systemic chemotherapy (NIPS), early postoperative intraperitoneal chemotherapy (EPIC), sequential postoperative intraperitoneal chemotherapy (SPIC), normothermic intraperitoneal chemotherapy (NIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). To promote the standardized application of intraperitoneal chemotherapy, further research on the mechanisms underlying peritoneal metastasis of colorectal cancer, selection of effective intraperitoneal chemotherapy agents, determination of optimal timing and administration protocols, exploration of the feasibility of sequential intraperitoneal chemotherapy and conduction of valuable basic and clinical research are currently needed. This paper will review the development and origins of intraperitoneal chemotherapy, treatment modalities, as well as the current application status and prospects of various treatment approaches in the context of peritoneal metastasis of colorectal cancer.

Assessment of Intraoperative Scoring Systems for Predicting Cytoreduction Outcome in Peritoneal Metastatic Disease: A Systematic Review and Meta-analysis.

Cytoreductive surgery (CRS) is a widely acknowledged treatment approach for peritoneal metastasis, showing favorable prognosis and long-term survival. Intraoperative scoring systems quantify tumoral burden before CRS and may predict complete cytoreduction (CC). This study reviews the intraoperative scoring systems for predicting CC and optimal cytoreduction (OC)and evaluates the predictive performance of the Peritoneal Cancer Index (PCI) and Predictive Index Value (PIV). Systematic searches were conducted in Embase, MEDLINE, and Web of Science. Meta-analyses of extracted data were performed to compare the absolute predictive performances of PCI and PIV. Thirty-eight studies (5834 patients) focusing on gynecological (n = 34; 89.5%), gastrointestinal (n = 2; 5.3%) malignancies, and on tumors of various origins (n = 2; 5.3%) were identified. Seventy-seven models assessing the predictive performance of scoring systems (54 for CC and 23 for OC) were identified with PCI (n = 39/77) and PIV (n = 16/77) being the most common. Twenty models (26.0%) reinterpreted previous scoring systems of which ten (13%) used a modified version of PIV (reclassification). Meta-analyses of models predicting CC based on PCI (n = 21) and PIV (n = 8) provided an AUC estimate of 0.83 (95% confidence interval [CI] 0.79-0.86; Q = 119.6, p = 0.0001; I2 = 74.1%) and 0.74 (95% CI 0.68-0.81; Q = 7.2, p = 0.41; I2 = 11.0%), respectively. Peritoneal Cancer Index models demonstrate an excellent estimate of CC, while PIV shows an acceptable performance. There is a need for high-quality studies to address management differences, establish standardized cutoff values, and focus on non-gynecological malignancies.

Resiquimod-loaded cationic liposomes cure mice with peritoneal carcinomatosis and induce specific anti-tumor immunity

Peritoneal carcinomatosis (PC) is characterized by a high recurrence rate and mortality following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC), primarily due to incomplete cancer elimination. To enhance the standard of care for PC, we developed two cationic liposomal formulations aimed at localizing a toll-like receptor agonist, resiquimod (R848), in the peritoneal cavity to activate the immune system locally to specifically eradicate residual tumor cells. These formulations effectively extended R848 retention in the peritoneum by >10-fold, resulting in up to a 2-fold increase in interferon α (IFN-α) induction in the peritoneal fluid, without increasing the plasma levels. In a CT26 colon cancer model with peritoneal metastases, these liposomal R848 formulations, when combined with oxaliplatin (OXA)—an agent used in HIPEC that induces immunogenic cell death—increased tumor infiltration of effector immune cells, including DCs, CD4, and CD8 T cells. This led to the complete elimination of PC in 60–70% of the mice, while the control mice reached humane endpoints by 30 days. The cured mice developed specific antitumor immunity, as re-challenging them with the same tumor cells did not result in tumor establishment. However, inoculation with a different tumor line led to tumor development. Additionally, exposing CT26 tumor antigens to the splenocytes isolated from the cured mice induced the expansion of CD4 and CD8 T cells and the release of IFN-γ, demonstrating long-term immune memory to the specific tumor. The anti-tumor efficacy of these liposomal R848 formulations was mediated via CD8 T cells with different levels of involvement of CD4 and B cells, and the combination with an anti-PD-1 antibody achieved a cure rate of 90%.

Predictive value of C-X-C motif chemokine receptor 4-directed molecular imaging in patients with advanced adrenocortical carcinoma.

In patients affected with adrenocortical carcinoma (ACC), C-X-C motif chemokine receptor 4 (CXCR4) is highly expressed in sites of disease in an ex-vivo setting. We aimed to determine the predictive value of CXCR4-targeting [68Ga]Ga-PentixaFor PET/CT for outcome when compared to clinical parameters. We identified 41 metastasized ACC patients imaged with [68Ga]Ga-PentixaFor PET/CT. Scans were assessed visually and on a quantitative level by manually segmenting the tumor burden (providing tumor volume [TV], peak/mean/maximum standardized uptake values [SUV] and tumor chemokine receptor binding on the cell surface [TRB], defined as SUVmean multiplied by tumor volume). Clinical parameters included sex, previous therapies, age, Weiss-Score, and Ki67 index. Following imaging, overall survival (OS) was recorded. After [68Ga]Ga-PentixaFor PET/CT, median OS was 9 months (range, 1-96 months). On univariable analysis, only higher TRB (per 10ml, HR 1.004, 95%CI: 1.0001-1.007, P = 0.005) and presence of CXCR4-positive peritoneal metastases (PM) were associated with shorter OS (HR 2.03, 95%CI: 1.03-4.02, P = 0.04). Presence of CXCR4-positive liver metastases (LM) trended towards significance (HR 1.85, 0.9-4.1, P = 0.11), while all other parameters failed to predict survival. On multivariable analysis, only TRB was an independent predictor for OS (HR 1.0, 95%CI: 1.00-1.001, P = 0.02). On Kaplan-Meier analysis, TRB above median (13.3 months vs. below median, 6.4 months) and presence of CXCR4-positive PM (6.4 months, vs. no PM, 11.4 months) were associated with shorter survival (P < 0.05, respectively). Presence of LM, however, was also linked to less favorable outcome (8.5 months vs. no LM, 18.1 months), without reaching significance (P = 0.07). In advanced ACC, elevated tumor chemokine receptor binding on the tumor cell surface detected through [68Ga]Ga-PentixaFor PET/CT is an independent predictor for OS, while other imaging and clinical parameters failed to provide relevant prognostic information.

A radiomics-boosted deep-learning for risk assessment of synchronous peritoneal metastasis in colorectal cancer

ObjectivesSynchronous colorectal cancer peritoneal metastasis (CRPM) has a poor prognosis. This study aimed to create a radiomics-boosted deep learning model by PET/CT image for risk assessment of synchronous CRPM.MethodsA total of 220 colorectal cancer (CRC) cases were enrolled in this study. We mapped the feature maps (Radiomic feature maps (RFMs)) of radiomic features across CT and PET image patches by a 2D sliding kernel. Based on ResNet50, a radiomics-boosted deep learning model was trained using PET/CT image patches and RFMs. Besides that, we explored whether the peritumoral region contributes to the assessment of CRPM. In this study, the performance of each model was evaluated by the area under the curves (AUC).ResultsThe AUCs of the radiomics-boosted deep learning model in the training, internal, external, and all validation datasets were 0.926 (95% confidence interval (CI): 0.874–0.978), 0.897 (95% CI: 0.801–0.994), 0.885 (95% CI: 0.795–0.975), and 0.889 (95% CI: 0.823–0.954), respectively. This model exhibited consistency in the calibration curve, the Delong test and IDI identified it as the most predictive model.ConclusionsThe radiomics-boosted deep learning model showed superior estimated performance in preoperative prediction of synchronous CRPM from pre-treatment PET/CT, offering potential assistance in the development of more personalized treatment methods and follow-up plans.Critical relevance statementThe onset of synchronous colorectal CRPM is insidious, and using a radiomics-boosted deep learning model to assess the risk of CRPM before treatment can help make personalized clinical treatment decisions or choose more sensitive follow-up plans.Key PointsPrognosis for patients with CRPM is bleak, and early detection poses challenges.The synergy between radiomics and deep learning proves advantageous in evaluating CRPM.The radiomics-boosted deep-learning model proves valuable in tailoring treatment approaches for CRC patients.Graphical

The Ugly: Metastatic Colon Cancer—Surgical Options

AbstractOver 50% of patients with colorectal cancer develop metastatic disease. Although systemic therapy remains the backbone of palliative treatment, select patients may be candidates for surgical resection with curative intent. Given increasing evidence of the association between metastasectomy and prolonged survival, surgery has acquired an increasingly central role in the management of liver, lung, and peritoneal metastases. This is compounded by accumulating advances in local and systemic treatments that have allowed for expansion of the resectability pool, bringing the potential for curative surgical treatment to increasing numbers of patients with stage IV disease. However, as the boundaries of resectability are pushed, patient selection and consideration of tumor-related and technical factors are imperative to the identification of patients for whom surgery would be of the greatest benefit.

Enhancing ovarian cancer treatment with maleimide-modified Pt(IV) prodrug nanoparticles

The limitations of platinum in ovarian cancer therapy, such as poor solubility and significant side effects, often lead to suboptimal therapeutic outcome and mortality. In this study, we have developed a novel approach utilizing biodegradable polymeric nanoparticles as a drug delivery system (NDDS), loaded with advanced platinum (IV) (Pt(IV)) prodrugs. A key feature of our approach is the enhancement of nanoparticles with maleimide, a modification hypothesized to significantly boost tumor tissue accumulation. When tested in mouse models of orthotopic and peritoneal metastasis ovarian cancer, these maleimide-modified nanoparticles are anticipated to show preferential accumulation in tumor tissues, enhancing therapeutic efficiency and minimizing systemic drug exposure. Our findings demonstrate that the maleimide-modified Pt(IV)-loaded NDDSs significantly reduce tumor burden in comparison to traditional cisplatin therapy, while simultaneously reducing adverse side effects. This leads to markedly improved survival rates in models of peritoneal metastasis ovarian cancer, offering a promising new direction in the treatment of this challenging disease.

Development of a deep learning survival model to predict the individual risks of peritoneal metastasis of colorectal cancer

Background : Peritoneal metastasis (PM) has been considered to be the terminal stage of colorectal cancer (CRC) due to poor prognosis. We purposed to construct an AI model of clinicopathological parameters to predict the survival prognosis of PM in CRC. Methods : Our model was constructed through modifying a classic neural network with COX proportional hazards as loss function in the training cohort. It is able to predict the overall survival (OS) of each individual patient with clinicopathological parameters. Multivariate analysis was conducted to identify independent risk factors for the prognosis of PM patients. Results and Conclusion : In the testing cohort, the deep learning model show good performance with the c-index of 0.76 and brier score of 0.20. Conclusions : We have developed a deep learning model to predict the survival of individual patients precisely. It can provide evidence to apply personalized treatments and assisted surgeon to select optical treatments for CRC patients with PM.

Advanced Gastric Cancer: Single-Center Experience

Gastric cancer (GC) is the fifth most diagnosed cancer, but it is the third leading cause of cancer death worldwide. Despite the likelihood of gastric cancer metastasizing to the peritoneum, optimal management strategies for this population remain undefined. We carried out a retrospective analysis to present our findings on patients with advanced gastric cancer (AGC) with peritoneal metastases (CP) who underwent neoadjuvant chemotherapy followed by gastrectomy + hyperthermic intraperitoneal chemotherapy (HIPEC). To better understand the data, we compared these patients with AGC patients without CP who were treated with neoadjuvant chemotherapy and surgery, as well as with another group of patients who underwent upfront surgery. Patients who undergo surgery and HIPEC achieve a higher survival rate than patients in the literature who undergo only palliative chemotherapy with a median overall survival of 28 months with a low incidence of major complications.

Tc-99m-MDP Uptake in Extraosseous Metastases from Ovarian Papillary Serous Adenocarcinoma.

The uptake of Tc-99m-uptake of Tc-99m-methylene diphosphonate (MDP) on bone scintigraphy can be seen at sites other than bone in a varying number of benign and malignant conditions. Extraosseous metastatic calcifications can occur in ovarian papillary serous adenocarcinoma (PSAC). These extraosseous calcifications show Tc-99m-MDP uptake. We report a case of a female in her sixties who had a previous history of PSAC of the ovary. The patient had undergone neoadjuvant chemotherapy (NACT) followed by total abdominal hysterectomy and bilateral salpingo-oophorectomy. She also received adjuvant chemotherapy. Tc-99m-MDP bone scan was performed post chemotherapy because the patient complained of lower backache. The scan showed increased uptake in the lower thoracic and lumbar vertebral regions. However, single-photon emission computed tomography/computed tomography (CT) localizes the uptake to metastatic calcified peritoneal deposits. Further 18F-fluorodeoxyglucose positron emission tomography/CT confirmed widespread peritoneal and omental metastatic disease with increased uptake.

Ileal perforation at the site of peritoneal metastasis with intestinal infiltration by dual EGFR-VEGF pathway inhibition in an EGFR-mutant non-small cell lung cancer patient.

Gastrointestinal (GI) perforation including ileal perforation is a rare complication of antivascular endothelial growth factor (anti-VEGF) therapy. Risk factors of GI perforation have not been fully understood. This report highlights the case of a patient who experienced GI perforation at the site of peritoneal metastasis with intestinal infiltration immediately after treatment with dual epidermal growth factor receptor (EGFR)-VEGF pathway inhibition agents for EGFR-mutant non-small cell lung cancer (NSCLC). The administration of dual EGFR-VEGF pathway inhibition agents in EGFR mutant NSCLC patients appears to elevate the risk of GI perforation. This report provides insights into the association between EGFR mutant NSCLC and the susceptibility to GI perforation following treatment with dual EGFR-VEGF pathway inhibition agents.

Safety evaluation of biopolymer immune implants in rats and rabbits as well as therapeutic effects on gastric cancer peritoneal metastasis carcinoma

Safety evaluation of biopolymer immune implants in rats and rabbits as well as therapeutic effects on gastric cancer peritoneal metastasis carcinoma

ASO Author Reflections: Important Predictive Factors for Prognosis in Patients with Peritoneal Metastasis of Gastric Cancer.

ASO Author Reflections: Important Predictive Factors for Prognosis in Patients with Peritoneal Metastasis of Gastric Cancer.

Outcome of patients with peritoneal metastasis from ovarian cancer treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC).

There are few data on Pressurized IntraPeritoneal Aerosol Chemotherapy with cisplatin and doxorubicin (PIPAC C/D) in women with primary unresectable or recurrent platinum-resistant peritoneal metastasis (PM) from ovarian cancer (OC). We evaluated survival, histological and cytological response, Quality of Life (QoL) and toxicity after PIPAC C/D in these patients. Retrospective analysis of patients from the prospective PIPAC-OPC1 and -OPC2 studies. The histological response was evaluated by the Peritoneal Regression Grading Score (PRGS). QoL questionnaires were collected at baseline and after third PIPAC or 60days. Adverse events were collected until 30days after the last PIPAC. Demographic and survival data were analysed based on intention to treat. Response, QoL and toxicity were analysed per protocol (≥1 PIPAC). Twenty-nine patients were included. Five patients (17 %) were non-accessible at PIPAC 1. One patient was excluded due to liver metastases at PIPAC 1. Thus, 23 patients had 76 PIPACs (median 2, range 1-12). Median overall survival was 8.2months (95 % CI 4.4-10.3) from PIPAC 1. Biopsy data were available for 22 patients, and seven (32 %) patients had a major/complete histological response (PRGS≤2) at PIPAC 3. No cytological conversions were registered. Symptoms and function scores worsened, while emotional scores improved. Three patients had severe adverse reactions (two ileus, one pulmonary embolism); no life-threatening reactions or treatment-related mortality was observed. PIPAC C/D was feasible and induced histological regression in a substantial proportion of patients with platinum-resistant PM from OC. Larger studies are needed to evaluate impact on survival.