Specific lineage transition of tumor-associated macrophages elicits immune evasion of ascitic tumor cells in gastric cancer with peritoneal metastasis

BACKGROUND

Gastric cancer with peritoneal metastasis (PM-GC), recognized as one of the deadliest cancers. However, whether and how the tumor cell-extrinsic tumor microenvironment (TME) is involved in the therapeutic failure remains unknown. Thus, this study systematically assessed the immunosuppressive tumor microenvironment in ascites from patients with PM-GC, and its contribution to dissemination and immune evasion of ascites-disseminated tumor cells (aDTCs).

METHODS

Sixty-three ascites and 43 peripheral blood (PB) samples from 51 patients with PM-GC were included in this study. aDTCs in ascites and circulating tumor cells (CTCs) in paired PB were immunophenotypically profiled. Using single-cell RNA transcriptional sequencing (scRNA-seq), crosstalk between aDTCs and the TME features of ascites was inspected. Further studies on the mechanism underlying aDTCs-immune cells crosstalk were performed on in vitro cultured aDTCs.

RESULTS

Immune cells in ascites interact with aDTCs, prompting their immune evasion. Specifically, we found that the tumor-associated macrophages (TAMs) in ascites underwent a continuum lineage transition from cathepsinhigh (CTShigh) to complement 1qhigh (C1Qhigh) TAM. CTShigh TAM initially attracted the metastatic tumor cells to ascites, thereafter, transitioning terminally to C1Qhigh TAM to trigger overproliferation and immune escape of aDTCs. Mechanistically, we demonstrated that C1Qhigh TAMs significantly enhanced the expression of PD-L1 and NECTIN2 on aDTCs, which was driven by the activation of the C1q-mediated complement pathway.

CONCLUSIONS

For the first time, we identified an immunosuppressive macrophage transition from CTShigh to C1Qhigh TAM in ascites from patients with PM-GC. This may contribute to developing potential TAM-targeted immunotherapies for PM-GC.

Low-dose radiotherapy synergizes with iRGD-antiCD3-modified T cells by facilitating T cell infiltration

BACKGROUND AND PURPOSE

Poor penetration of transferred T cells represents a critical factor impeding the development of adoptive cell therapy in solid tumors. We demonstrated that iRGD-antiCD3 modification promoted both T cell infiltration and activation in our previous work. Interest in low-dose radiotherapy has recently been renewed due to its immuno-stimulatory effects including T cell recruitment. This study aims to explore the synergistic effects between low-dose radiotherapy and iRGD-antiCD3-modified T cells.

MATERIALS AND METHODS

Flow cytometry was performed to assess the expression of iRGD receptors and chemokines. T cell infiltration was evaluated by immunohistofluorescence and in vivo real-time fluorescence imaging and antitumor effects were investigated by in vivo bioluminescence imaging in the gastric cancer peritoneal metastasis mouse model.

RESULTS

We found that 2 Gy irradiation upregulated the expression of all three iRGD receptors and T-cell chemokines. The addition of 2 Gy low-dose irradiation boosted the accumulation and penetration of iRGD-antiCD3-modified T cells in peritoneal tumor nodules. Combining 2 Gy low-dose irradiation with iRGD-antiCD3-modified T cells significantly inhibited tumor growth and prolonged survival in the peritoneal metastasis mouse model with a favorable safety profile.

CONCLUSION

Altogether, we demonstrated that low-dose radiotherapy could improve the antitumor potency of iRGD-antiCD3-modified T cells by promoting T cell infiltration, providing a rationale for exploring low-dose radiotherapy in combination of other adoptive T cell therapies in solid tumors.

Dual-energy CT quantitative parameters to evaluate occult peritoneal metastasis in advanced gastric cancer preoperatively

PURPOSE

To explore whether dual-energy CT (DECT) quantitative parameters could provide analytic value for the diagnosis of patients with occult peritoneal metastasis (OPM) in advanced gastric cancer preoperatively.

MATERIALS AND METHODS

This retrospective study included 219 patients with advanced gastric cancer and DECT scans. The patient's clinical data and DECT related iodine concentration (IC) parameters and effective atomic number (Zeff) were collated and analyzed among noun-peritoneal metastasis (NPM), OPM and radiologically peritoneal metastasis (RPM) groups. The predictive performance of the DECT parameters was compared with that of the conventional CT features and clinical characteristics through evaluating area under curve of the precision-recall (AUC-PR), F1 score, balanced accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

RESULTS

Borrmann IV type diagnosed on CT and serum tumor indicator CA125 index were statistically different between the NPM and OPM groups. DECT parameters included IC, normalized IC (NIC), and Zeff of PM group were lower than the NPM group. The DECT predictive nomogram combined three independent DECT parameters produced a better diagnostic performance than the conventional CT feature Borrmann IV type and serum CA125 index in AUC-PR with 0.884 vs 0.368 vs 0.189, but similar to the combined indicator which was based on the DECT parameters, the conventional CT feature, and serum CA125 index in AUC-PR with 0.884 vs 0.918.

CONCLUSION

The lower quantitative NIC, IC ratio, and Zeff on DECT was associated with peritoneal metastasis in advanced gastric cancer and was promising to identify patients with OPM noninvasively.

Detection of Residual Peritoneal Metastases Following Cytoreductive Surgery Using Pegsitacianine, a pH-Sensitive Imaging Agent: Final Results from a Phase II Study

BACKGROUND

For patients with peritoneal carcinomatosis, extent of disease and completeness of cytoreductive surgery (CRS) are major prognostic factors for long-term survival. Assessment of these factors could be improved using imaging agents. Pegsitacianine is a pH-sensitive polymeric micelle conjugated to the fluorophore indocyanine green. The micelle disassembles in acidic microenvironments, such as tumors, resulting in localized fluorescence unmasking. We assessed the utility of pegsitacianine in detecting residual disease following CRS.

PATIENTS AND METHODS

NCT04950166 was a phase II, non-randomized, open-label, multicenter US study. Patients eligible for CRS were administered an intravenous dose of pegsitacianine at 1 mg/kg 24-72 h before surgery. Following CRS, the peritoneal cavity was reexamined under near-infrared (NIR) illumination to evaluate for fluorescent tissue. Fluorescent tissue identified was excised and evaluated by histopathology. The primary outcome was the rate of clinically significant events (CSE), defined as detection of histologically confirmed residual disease excised with pegsitacianine or a revision in the assessment of completeness of CRS. Secondary outcomes included acceptable safety and pegsitacianine performance.

RESULTS

A total of 53 patients were screened, 50 enrolled, and 40 were evaluable for CSE across six primary tumor types. Residual disease was detected with pegsitacianine in 20 of 40 (50%) patients. Pegsitacianine showed high sensitivity and was well tolerated with no serious adverse events (SAEs). Transient treatment-related, non-anaphylactic infusion reactions occurred in 28% of patients.

CONCLUSIONS

Pegsitacianine was well tolerated and facilitated the recognition of occult residual disease following CRS. The high rate of residual disease detected suggests that the use of pegsitacianine augmented surgeon assessment and performance during CRS.

Cytoreduction surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) as treatment choice of metastatic Urachal carcinoma

INTRODUCTION

Urachal carcinoma accounts for approximately 0.01 % of all adult malignancies and 1 % of bladder cancers. Its prognosis remains poor, with a 5-year overall survival rate of less than 50 %.

PRESENTATION OF CASE

A 51-years-old black female, affected by peritoneal malignancies from urachal carcinoma, underwent multiple surgical cytoreduction (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) with different chemotherapy regimen, alternating with intravenous chemotherapy. Thirty-two months recurrence-free survival was registered, and overall survival was more than 5 years.

DISCUSSION

Our case suggests the importance of rigorous follow-up with both tumor marker testing (CEA) and imaging studies. Optimal debulking surgery plays a pivotal role in controlling primary and recurrent disease. The use of combined intraperitoneal and intravenous chemotherapy may have contributed to her long-term survival.

CONCLUSION

CRS and HIPEC combined with intravenous chemotherapy may be potential candidates for treating patients with urachal carcinoma with peritoneal metastases. Our patient is a challenging case in daily surgical practice.

Meet-Uro27

BACKGROUND

Peritoneal metastases (PM) have been reported in approximately 1% of patients with metastatic Renal Cell Carcinoma (mRCC). Outcome data are limited due to the rarity of this metastatic site. Therefore, the aim of our study is to describe renal cell carcinoma (RCC) patients with PM treated as per clinical practice.

MATERIALS AND METHODS

Baseline characteristics and outcome data of patients with PM from RCC were retrospectively collected from 18 Italian oncological referral centers adhering to the Meet-Uro group, from January 2016 to January 2023.

RESULTS

We collect 81 RCC patients with PM. 78/81 received systemic treatment, 3/81 only best supportive care. First line treatment included tyrosine-kinase inhibitors (TKI) (46/78), ImmuneOncology (IO)-TKI (26/78) and IO-IO (6/78), with different Objective Response Rate (ORR) (43.4% in TKI monotherapy group vs 50% in IO-TKI group, respectively) and Disease Control Rate (DCR) (60.8% in TKI treated patients vs. 76.9% in IO-TKI treated patients). Median PFS was 6.4 months (95%CI 4.18-14.8) in patients treated with TKI monotherapy vs 23.7 months (95%CI 11.1-NR) in patients treated with IO-TKI (p < 0.015). The median OS (mOS) was 22.7 months (95%CI 13.32 - 64.7) in the TKI monotherapy group vs 34.5 mo (95%CI NR-NR) in the IO-TKI group with 53.8% of patients alive at 1 years in the latter group, (p < 0.16). Primary refractory patients were 36.9% for TKI and 15.3% for IO-TKI. According to International Metastatic renal cell carcinoma Database Consortium (IMDC) score, mPFS and mOS were consistent among risk categories. Median PFS was 36.6 months (95%CI 10.9-NR) for good risk patients compared to 10 months (95%CI 7.5-29.8) for intermediate risk and 2.96 months (95%CI 2.43-11.28) for poor risk population (p < 0.0005) whereas mOS was NR (95%CI 28.65-NR) for good risk patients compared to 35.3 months (95%CI 24.6-NA) and 12.4 months (95%CI 3.52-NR) for intermediate and poor risk population, respectively, (p < 0.0002). Only 34/78 (43.5%) received a second line treatment that was TKI (ORR 8.3% and DCR 41.6%) or IO (ORR 18.1% and DCR 40.9%).

CONCLUSION

We report one of the largest case series regarding PM from RCC. Characteristics of patients suggest a more aggressive behavior of PM from mRCC. Outcome data suggest that TKI-IO as first line treatment, and TKI as second line, confirm their activity for these patients with dismal prognosis.

Genetic specificity study using next-generation sequencing (NGS) of peritoneal metastatic colorectal cancer compared to primary colorectal cancer

BACKGROUND

In patients with colorectal cancer, peritoneal metastases are the second most frequent metastatic lesion after liver metastases. Peritoneal metastases have a very poor prognosis, with a median survival time of 5-7 months. Currently, there is a lack of research on the genetic differences between primary colorectal cancer and peritoneal metastases. Therefore, we aimed to identify their genetic characteristics through a cancer panel test using next-generation sequencing.

OBJECTIVE

We aim to investigate the specificity of genetic variants in primary colorectal cancer and peritoneal metastases.

METHODS

We recruited patients with stage I, II, and III primary colorectal cancer and peritoneal metastases for genetic analysis using NGS. Samples were collected from patients who underwent surgery at Dankook University Hospital and consented to genetic testing. NGS was performed using a cancer panel.

RESULTS

Among 36 patients with primary cancer, TP53 gene mutation was identified the most in 25 patients (69%), followed by APC gene mutation in 19 patients (53%), and KRAS gene mutation in 17 patients (47%). In the peritoneal metastasis patient group, unlike the primary cancer patient group, KRAS gene mutations were the most common 6 patients (55%), followed by TP53 gene mutations in 4 patients (36%) and PIK3CA gene mutations in 2 patients (18%).

CONCLUSION

The small number of surgical cases of peritoneal metastases was a limitation of our sample size. Nevertheless, we identified differences in the alterations of specific genes between primary and peritoneal metastases. Acquiring additional cases and collecting more data will provide deeper insights into these cancers.

N6-methyladenosine-modified MIB1 promotes stemness properties and peritoneal metastasis of gastric cancer cells by ubiquitinating DDX3X

BACKGROUND

Peritoneal metastasis (PM), one of the most typical forms of metastasis in advanced gastric cancer (GC), indicates a poor prognosis. Exploring the potential molecular mechanism of PM is urgently necessary, as it has not been well studied. E3 ubiquitin ligase has been widely established to exert a biological function in various cancers, but its mechanism of action in GC with PM remains unknown.

METHODS

The effect of MIB1 on PM of GC was confirmed in vitro and in vivo. Co-immunoprecipitation (Co-IP) and mass spectrometry demonstrated the association between MIB1 and DDX3X. Western blot, flow cytometry and immunofluorescence determined that DDX3X was ubiquitylated by MIB1 and promoted stemness. We further confirmed that METTL3 promoted the up-regulation of MIB1 by RNA immunoprecipitation (RIP), luciferase reporter assay and other experiments.

RESULTS

We observed that the E3 ubiquitin ligase Mind bomb 1 (MIB1) was highly expressed in PMs, and patients with PM with high MIB1 expression showed a worse prognosis than those with low MIB1 expression. Mechanistically, our study demonstrated that the E3 ubiquitin ligase MIB1 promoted epithelial-mesenchymal transition (EMT) progression and stemness in GC cells by degrading DDX3X. In addition, METTL3 mediated m6A modification to stabilize MIB1, which required the m6A reader IGF2BP2.

CONCLUSIONS

Our study elucidated the specific molecular mechanism by which MIB1 promotes PM of GC, and suggested that targeting the METTL3-MIB1-DDX3X axis may be a promising therapeutic strategy for GC with PM.

Appendiceal adenocarcinoma, diagnosed after acute perforated appendicitis: Potential contribution of HIPEC

INTRODUCTION

Treatment of peritoneal metastasis from appendicular adenocarcinoma consists of cyto-reductive surgery (CRS) and Hyperthermic IntraPEritoneal Chemotherapy (HIPEC). In case of acute appendicular syndrome (AAS) the tumor is likely to be perforated. In that case, there is no treatment recommendation. We propose CRS and HIPEC.

MATERIALS AND METHOD

We listed 21 consecutive patients who were addressed for discovery of appendiceal adenocarcinoma. The emergency surgery was performed in a primary-care hospital. We evaluated the therapeutic algorithms, per operative decision, survival and recurrent rate.

RESULTS

Among the 21 patients, 4 patients were diagnosed as synchronous appendicular peritoneal metastasis, and underwent CRS and HIPEC. The other 17 patients with diagnosis of adenocarcinoma on anatomopathological samples, without peritoneal metastasis during appendectomy, were addressed. Between them 2 patients were denied CRS. Among the 15 operated patients, 8 patients had no peritoneal metastasis discovery during surgery, and therefore underwent prophylactic CRS and HIPEC. Peritoneal metastasis were discovered for the other 7 patients, who also underwent CRS and HIPEC. For the prophylactic group, the recurrence rate is 12,5 %, overall survival (OS) is 100 %. The rate of grade III-IV surgical complications after CRS and HIPEC was 36 % among the 19 patients who underwent surgery.

CONCLUSION

In case of appendectomy in emergency situations for perforated adenocarcinoma, half of the patients may have peritoneal metastasis. In case of non-identified peritoneal metastasis during CRS, performing a prophylactic HIPEC seems to be associated with an encouraging rate of peritoneal disease free situation at 5 years.

Oncological outcomes of conversion therapy in gastric cancer patients with peritoneal metastasis: a large-scale retrospective cohort study

BACKGROUND

Data on the long-term oncological outcomes of patients who undergo conversion surgery (CS) in gastric cancer (GC) patients with peritoneal metastasis (PM) are limited.

METHODS

GC patients with PM who received intraperitoneal (ip) and systemic chemotherapy between April 2015 and January 2021 were enrolled. Multivariate analysis was performed to identify risk factors associated with survival. Clinicopathological and survival outcomes were compared between those with CS and those without CS (NCS). The paclitaxel (PTX) plus tegafur-gimeracil-oteracil potassium capsules (S-1) (PS) + ip PTX and oxaliplatin plus S-1 (SOX) + ip PTX groups were matched in a 1:1 ratio using propensity score matching. Oncological and survival data were collected and analyzed.

RESULTS

A total of 540 patients who received ip chemotherapy via subcutaneous port and systemic chemotherapy were analyzed and 268 patients were enrolled, including 113 who underwent CS and 155 who did not. Overall survival (OS) were 27.0 months and 11.8 months in the CS and NCS groups (P < 0.0001), respectively. R0 resection was an independent prognostic factor for patients who underwent CS. The OS of patients with or without ovariectomy was 21.3 or 12.0 months (P < 0.0001). No difference of clinicopathological and survival outcomes was found between the PS + ip PTX and SOX + ip PTX groups.

CONCLUSION

Conversion therapy is safe and adverse events were manageable. CS improves the survival of GC patients with PM after ip and systemic chemotherapy. R0 is an important prognostic factor. Furthermore, outcomes are comparable between the PS + ip PTX and SOX + ip PTX groups.

Conversion therapy with pembrolizumab for a peritoneal metastasis of rectal cancer causing hydronephrosis in a patient with Lynch syndrome

A 44-year-old woman with Lynch syndrome was referred to our hospital for treatment of recurrence of microsatellite instability-high rectal cancer. [18F]Fluorodeoxyglucose (18FDG)-positron emission tomography revealed a peritoneal metastasis with invasion to the small intestine and left ureter. The peritoneal metastasis was diagnosed initially as unresectable because of extensive invasion to the left ureter requiring nephrectomy. Hence, first-line treatment with pembrolizumab was started. After the first course of pembrolizumab, she developed hydronephrosis and a resulting urinary tract infection (UTI). A percutaneous nephrostomy was performed to control the UTI. After six courses of pembrolizumab, 18FDG-positron emission tomography showed that the peritoneal metastasis was smaller with significantly reduced 18FDG uptake, and it was then diagnosed as resectable without nephrectomy. She underwent R0 resection of the peritoneal metastasis with partial resection of the small intestine. Intraoperatively, the peritoneal metastasis showed no invasion of the left ureter, allowing its preservation. The percutaneous nephrostomy was removed postoperatively, and she has not developed any subsequent UTIs. Histopathologically, the tumor showed a pathological complete response to pembrolizumab. To the best of our knowledge, this is the first case of conversion therapy with pembrolizumab for peritoneal metastasis with hydronephrosis.

Prophylactic hyperthermic intraperitoneal chemotherapy in T4 colorectal cancer: Can it improve the oncologic prognosis? - A propensity score matching study

BACKGROUND

Some studies show that cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) may improve overall survival and is a possible curative treatment for selected colorectal cancer (CRC) patients with restricted peritoneal metastasis (PM). The value of HIPEC in preventing PM of CRC is still controversial.

MATERIALS AND METHODS

In this retrospective propensity score matching (PSM) cohort study, all patients with cT4N0-2M0 undergoing treatment at a single institution in China (2014-2018) were reviewed. The 3-year disease-free survival (DFS) was set as the primary outcome, and the 3-year PM rate was also analyzed.

RESULTS

220 patients were included in this study for analysis. After 1:3 PSM: HIPEC (n = 45) and No HIPEC (n = 135). Through analysis, it was found that prophylactic HIPEC correlated to better DFS [hazard ratio (HR) 0.43, 95 % confidence interval (CI) 0.19-0.95; p = 0.037], and N2 stage correlated to worse DFS [HR 1.97, 95 % CI 1.09-3.56; p = 0.025]. For laparoscopic surgery subgroup analyses, 3-year PM rate of patients with laparoscopic surgery was 13.8 % in No HIPEC group, and 2.6 % in HIPEC group (p = 0.070). Besides, no post-operative death occurred, the anastomotic leakage rate was 2.2 % in HIPEC group and 0.7 % in the control group (p = 0.439).

CONCLUSIONS

Prophylactic HIPEC may improve the prognosis in patients with cT4N0-1M0 CRC, but not in cT4N2M0 CRC, and it does not significantly increase surgery-related complications. Laparoscopic surgery followed by HIPEC for T4 stage CRC may not increase risk of PM.

Early port site and peritoneal metastasis following robot-assisted radical cystectomy: a rare case report

Radical cystectomy with pelvic lymph node dissection is the recommended treatment for managing muscle-invasive carcinoma of the urinary bladder. Early recurrence is observed in only about 4.1% of cases. Port-site metastasis following robot-assisted radical cystectomy is extremely rare. We encountered a challenging and a rare case of bladder cancer that manifested with port-site and peritoneal metastasis within 6 weeks of surgery.

miR-1286, a Tumor Suppressor of Gastric Cancer, Serves as a Promising Biomarker for Screening Gastric Cancer from Gastritis

Gastric cancer (GC) is one of the crucial causes of cancer-associated death worldwide. This study aimed to investigate the biological function of miR-1286 in GC progression in vitro, evaluate the clinical value of serum miR-1286 to screen GC patients and explore its relationship with helicobacter pylori (HP) infection and peritoneal metastasis in GC patients. Expression of miR-1286 was measured by RT-qPCR. Cell Counting Kit-8 assay was utilized for measuring GC cell proliferation ability. The migration and invasion abilities of GC cells were measured using Transwell assays. Serum samples were obtained from 108 GC patients, 62 gastritis cases and 62 healthy volunteers. The diagnostic performance of miR-1286 was assessed using ROC analysis, and the predictive value of miR-1286 for peritoneal metastasis onset was analyzed using logistic regression analysis. miR-1286 played as a tumor suppressor in GC progression by inhibiting GC cell proliferation, migration and invasion. In GC patients, significantly decreased miR-1286 was observed compared to gastritis and healthy controls, and had considerable diagnostic accuracy to distinguish GC from the controls. A significant association was found between miR-1286 expression and HP infection, peritoneal metastasis and TNM stage. Moreover, miR-1286 was lowly expressed in GC patients with peritoneal metastasis, and independently predicted the occurrence of peritoneal metastasis in GC. miR-1286 acts as a tumor suppressor and a biomarker in GC, and is closely associated with HP infection and peritoneal metastasis onset. The methods to regulate miR-1286 may be novel strategies to improve the treatment of GC.

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.

Targeted delivery of cathepsin-activatable near-infrared fluorescence probe for ultrahigh specific imaging of peritoneal metastasis

Inadequate cytoreductive surgery (CRS) has been identified as a prognostic factor for poor patient outcomes in cases of peritoneal metastasis. While imaging probes are used to identify peritoneal metastasis to facilitate CRS, many of these probes exhibit high background signals, resulting in a significant delay in achieving a satisfactory tumor-to-normal ratio (TNR) due to prolonged clearance time. In this study, we designed a novel fluorescent probe named Tras-AA-Cy NH2, which enables the relatively rapid imaging of subcutaneous tumors and peritoneal tumors while maintaining a high TNR. Mechanistically, Tras-AA-Cy NH2 exhibits selective targeting towards the Human epidermal growth factor receptor 2 on the surface of cancer cells. Following internalization, it undergoes enzymatic cleavage catalyzed by the overexpressed cathepsin, leading to the subsequent release of near-infrared fluorophores. Consequently, Tras-AA-Cy NH2 achieved a TNR of 7.8 at 6 h and 21.4 at 24 h in subcutaneous tumor mice. Even after 522 h of in vivo circulation, the TNR remained above 5, indicating an ultralong imaging time window. It is noteworthy that Tras-AA-Cy NH2 has demonstrated successful utilization for peritoneal tumor-specific imaging and further affirmed its tumor tissue-specific recognition capability using human resected tissues. In summary, these findings underscore the rational design of Tras-AA-Cy NH2 for visualizing peritoneal tumors.

Combined Intraperitoneal Paclitaxel and Systemic Chemotherapy for Patients with Massive Malignant Ascites Secondary to Pancreatic Cancer: A Report of Two Patients

The prognosis of patients with peritoneal metastases from pancreatic cancer is poor, largely due to massive ascites, which precludes systemic treatment. Two patients with a poor performance status and malignant ascites were treated with cell-free and concentrated ascites reinfusion therapy followed by combined chemotherapy with intraperitoneal paclitaxel, intravenous gemcitabine, and nab-paclitaxel. These patients achieved a survival of 19 and 36 weeks with a relatively good quality of life. Combined intraperitoneal paclitaxel and systemic chemotherapy may provide effective palliative management for some patients with peritoneal metastases from pancreatic cancer.

Prognostic value of hyperthermic intraperitoneal chemotherapy in gastric cancer with synchronous peritoneal metastases: a real-world retrospective study

PURPOSE

Peritoneal metastasis in gastric cancer (GC) is a late-stage condition with a poor prognosis. Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a popular treatment for peritoneal metastases. Here, we aim to investigate the real-world application and efficacy of HIPEC alone for GC patients with synchronous peritoneal metastases.

METHODS

We conducted a retrospective analysis on GC patients with synchronous peritoneal metastasis at the Sixth Affiliated Hospital of Sun Yat-sen University between January 2011 and December 2022. Survival analyses and Cox regression models were performed based on overall survival (OS) and cancer-specific survival (CSS), and subgroup analysis was used to determine the prognostic value of HIPEC across different treatment.

RESULTS

We enrolled 250 patients, of whom 120 (48%) received HIPEC while 130 (52%) did not. HIPEC showed no survival benefit for GC patients (P = 0.220 for OS and P = 0.370 for CSS). However, subgroup analysis found that HIPEC can only improve OS and CSS when combined with primary tumor resection (P = 0.034 for OS and P = 0.036 for CSS). Moreover, survival analyses also demonstrated that HIPEC independently improved OS (HR for OS = 0.58, 95% CI 0.37-0.92, P = 0.020) and CSS (HR for CSS = 0.58, 95% CI 0.37-0.93, P = 0.024) for patients who underwent primary site resection, but not for those who did not.

CONCLUSION

HIPEC can improve survival in GC patients with synchronous peritoneal metastases who have primary tumor resection, but not in those without primary tumor resection.

Single-cell RNA sequencing reveals the lineage of malignant epithelial cells and upregulation of TAGLN2 promotes peritoneal metastasis in gastric cancer

BACKGROUND

Peritoneal metastasis (PM) is an important factor contributing to poor prognosis in patients with gastric cancer (GC). Transcriptomic sequencing has been used to explore the molecular changes in metastatic cancers, but comparing the bulk RNA-sequencing data between primary tumors and metastases in PM studies is unreasonable due to the small proportion of tumor cells in PM tissues.

METHODS

We performed single-cell RNA-sequencing analysis on four gastric adenocarcinoma specimens, including one primary tumor sample (PT), one adjacent nontumoral sample (PN), one peritoneal metastatic sample (MT) and one normal peritoneum sample (MN), from the same patient. Pseudotime trajectory analysis was used to display the process by which nonmalignant epithelial cells transform into tumor cells and then metastasize to the peritoneum. Finally, in vitro and in vivo assays were used to validate one of the selected genes that promote peritoneal metastasis.

RESULTS

Single-cell RNA sequencing showed that a development curve was found from normal mucosa to tumor tissues and then into metastatic sites on peritoneum. TAGLN2 was found to trigger this metastasis process. The migration and invasion capability of GC cells were changed by downregulating and upregulating TAGLN2 expression. Mechanistically, TAGLN2 might modulate tumor metastasis via alterations in cell morphology and several signaling pathways, thus promoting epithelial-mesenchymal transition (EMT).

CONCLUSIONS

In summary, we identified and validated TAGLN2 as a novel gene involved in GC peritoneal metastasis. This study provided valuable insight into the mechanisms of GC metastasis and developed a potential therapeutic target to prevent GC cell dissemination.

Exosomes released from PD-L1+ tumor associated macrophages promote peritoneal metastasis of epithelial ovarian cancer by up-regulating T cell lipid metabolism

Epithelial ovarian cancer (EOC) tends to metastasize to the peritoneum, and the prognosis of patients is poor. In the peritoneum of patients with EOC, TAMs (tumor associated macrophages) regulate the imbalance of T cell ratio and promote the progression and metastasis of EOC. However, the mechanism of peritoneal metastasis in EOC patients remains unclear. Here, we confirmed that the percentages of PD-L1+ TAMs in EOC tissues increased significantly, and TAMs-derived PD-L1+ exosomes affected the transcription factor PPARα to up-regulate the expression of CPT1A in CD8+ T cells, promote fatty acid oxidation, and increase reactive oxygen species to cause cell damage. The apoptosis of CD8+ T cells was increased, and the expressions of their exhaustion markers LAG3, TIM-3, and PD-1 were also up-regulated. TAMs affect T cell function through lipid metabolism, leading to peritoneal immune imbalance and promoting peritoneal metastasis of EOC. This study reveals the mechanism by which TAMs in the peritoneal microenvironment regulate T cell lipid metabolism through exosome delivery of PD-L1, and the effect of lipid metabolism on T cell function, reveals the molecular mechanism of tumor immune microenvironment affecting EOC metastasis, and further explores related pathways whether molecular blockade can be used as a means to intervene in disease progression is expected to establish a new strategy for the diagnosis and treatment of EOC.

CT-based deep learning model: a novel approach to the preoperative staging in patients with peritoneal metastasis

Peritoneal metastasis (PM) is a frequent manifestation of advanced abdominal malignancies. Accurately assessing the extent of PM before surgery is essential for patients to receive optimal treatment. Therefore, we propose to construct a deep learning (DL) model based on enhanced computed tomography (CT) images to stage PM preoperatively in patients. All 168 patients with PM underwent contrast-enhanced abdominal CT before either open surgery or laparoscopic exploration, and peritoneal cancer index (PCI) was used to evaluate patients during the surgical procedure. DL features were extracted from portal venous-phase abdominal CT scans and subjected to feature selection using the Spearman correlation coefficient and LASSO. The performance of models for preoperative staging was assessed in the validation cohort and compared against models based on clinical and radiomics (Rad) signature. The DenseNet121-SVM model demonstrated strong patient discrimination in both the training and validation cohorts, achieving AUC was 0.996 in training and 0.951 validation cohort, which were both higher than those of the Clinic model and Rad model. Decision curve analysis (DCA) showed that patients could potentially benefit more from treatment using the DL-SVM model, and calibration curves demonstrated good agreement with actual outcomes. The DL model based on portal venous-phase abdominal CT accurately predicts the extent of PM in patients before surgery, which can help maximize the benefits of treatment and optimize the patient's treatment plan.

Gastric cancer with peritoneal metastases: a single center outline and comparison of different surgical and intraperitoneal treatments

INTRODUCTION

Gastric cancer with peritoneal metastasis (GCPM) has an unfavourable prognosis. Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC) are promising treatment options that have been shown to improve survival. The aim of this study was to assess the impact of different treatments such as systemic chemotherapy, systemic chemotherapy + PIPAC, and CRS + HIPEC in patients with GCPM.

MATERIAL AND METHODS

This single-centre retrospective study included 82 patients with GCPM treated between January 2016 and June 2021. After first-line chemotherapy, depending on disease response and burden, the patients were divided into three treatment groups: chemotherapy alone, chemotherapy + PIPAC, and CRS + HIPEC. The primary outcome was overall survival (OS) from diagnosis, which was compared among the treatment groups.

RESULTS

Thirty-seven (45.1%) patients were administered systemic chemotherapy alone, 25 (30.4%) received chemotherapy + PIPAC, and 20 (24.4%) underwent CRS + HIPEC. The CRS + HIPEC group had better OS (median 24 months) than the PIPAC group (15 months, p = 0.01) and chemotherapy group (5 months, p = 0.0001). Following CRS + HIPEC, the postoperative grade 3-4 complication rate was 25%, and no postoperative in-hospital deaths occurred. The median disease-free survival (DFS) was 12 months. Multivariate analysis identified peritoneal carcinomatosis index (PCI) > 7 as an independent predictor of worse DFS. No independent predictors of OS were identified.

CONCLUSION

Among patients with GCPM, we identified a highly selected population with oligometastatic disease. In this group, CRS + HIPEC provided a significant survival advantage with an acceptable major complication rate compared with other available therapies (systemic chemotherapy alone or in combination with PIPAC).

High-precision detection and navigation surgery of colorectal cancer micrometastases

Surgical resection is an effective treatment for colorectal cancer (CRC) patients, whereas occult metastases hinder the curative effect. Currently, there is no effective method to achieve intraoperatively diagnosis of tumor-positive lymph nodes (LNs). Herein, we adopt a near-infrared-II (NIR-II) organic donor-pi-acceptor-pi-donor probe FE-2PEG, which exhibits bright fluorescence over 1100 nm, excellent photostability, blood circulation time, and biocompatibility, to achieve high-performance bioimaging with improved temporal and spatial resolution. Importantly, the FE-2PEG shows efficient passive enrichment in orthotopic CRC, metastatic mesenteric LNs, and peritoneal metastases by enhanced permeability and retention effect. Under NIR-II fluorescence-guided surgery (FGS), the peritoneal micrometastases were resected with a sensitivity of 94.51%, specificity of 86.59%, positive predictive value (PPV) of 96.57%, and negative predictive value of 79.78%. The PPV still achieves 96.07% even for micrometastases less than 3 mm. Pathological staining and NIR-II microscopy imaging proved that FE-2PEG could successfully delineate the boundary between the tumor and normal tissues. Dual-color NIR-II imaging strategy with FE-2PEG (1100 ~ 1300 nm) and PbS@CdS quantum dots (> 1500 nm) successfully protects both blood supply and normal tissues during surgery. The NIR-II-based FGS provides a promising prospect for precise intraoperative diagnosis and minimally invasive surgery of CRC.

A novel risk model for predicting peritoneal metastasis in colorectal cancer based on the SEER database

BACKGROUND

Early detection and intervention could significantly improve the prognosis of patients with peritoneal metastasis (PM). Our main purpose was to develop a model to predict the risk of PM in patients with colorectal cancer (CRC).

METHODS

Patients from the Surveillance, Epidemiology, and End Results (SEER) database with CRC classified according to the AJCC 8th TNM staging system were selected for the study. After data pre-processing, the dataset was divided into a training set and a validation set. In the training set, univariate logistic analysis and stepwise multivariate logistic regression analysis were utilized to screen clinical features and construct a risk prediction model. Then, we validated the model using the confusion matrix, receiver operating characteristic (ROC) curves, decision curve analysis (DCA), and calibration curves to examine its performance.

RESULTS

The model constructed using stepwise multivariate logistic regression analysis incorporated the following eight clinical features: age, tumor location, histological type, T stage, carcinoembryonic antigen (CEA) level, tumor deposits (TDs), log odds (LODDS) of metastatic lymph nodes, and extraperitoneal metastasis (EM). The areas under the curve (AUCs) of the model in the training and validation sets were 0.924 and 0.912, respectively. The accuracy and the recall ratio were higher than 0.8 in both cohorts. DCA and the calibration curves also confirmed its excellent predictive power.

CONCLUSIONS

Our model can effectively predict the risk of PM in CRC patients, which is of great significance for the timely identification of patients at high risk of PM and further clinical decision-making.

Prognostic Analysis of Prophylactic Hyperthermic Intraperitoneal Chemotherapy for Advanced Gastric Cancer: a Propensity Score-Matched Analysis

PURPOSE

To investigate the efficacy of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) for advanced gastric cancer (AGC).

METHODS

We included 198 patients treated from December 2016 to January 2019; of these patients, the 132 who had clinical T4 gastric cancer were divided into a hyperthermic intraperitoneal chemotherapy group (HIPEC group) and a radical gastrectomy and D2 lymph node dissection group (control group). Because this study was retrospective, we used propensity score matching (PSM) to reduce selectivity bias; we then assessed risk factors for recurrence and compared prognosis in terms of survival in the gastrectomy and prophylactic HIPEC groups.

RESULTS

Prophylactic HIPEC reduced the risk of postoperative peritoneal metastasis (PM: 27.5% vs. 10.5%, P = 0.015) and did not increase the risk of postoperative complications, but there was no significant difference in the effect on hepatic metastases or other distant metastases. Risk factors for recurrence included pT4 staging and positive lymph node metastases. Both disease-free survival (DFS: HR 0.592; 95% CI 0.354-0.990; P = 0.042) and peritoneal recurrence-free survival (PFS: HR 0.314; 95% CI 0.127-0.774; P = 0.008) were better in the prophylactic HIPEC group than in the gastrectomy-only group. In addition, there was no difference in the prognosis of patients between the two groups of raltitrexed (RT) and paclitaxel (PTX) for perfusion dosing.

CONCLUSION

Our study showed that prophylactic HIPEC could prevent postoperative PM in patients with AGC and did not increase the incidence of postoperative complications. However, it was not found to be effective in the prevention of other metastases, such as hepatic metastases.

Predictive performance of radiomics for peritoneal metastasis in patients with gastric cancer: a meta-analysis and radiomics quality assessment

PURPOSE

The purpose of this meta-analysis is to systematically review the diagnostic performance of radiomic techniques in predicting peritoneal metastasis in patients with gastric cancer, and to evaluate the quality of current research.

METHODS

We searched PubMed, Web of Science, EBSCO, Embase, and Cochrane databases for relevant studies up to April 3, 2023. Data extraction and quality evaluation were performed by two independent reviewers. Then we performed statistical analysis, including plotting the forest plot and summary receiver operating characteristic (SROC) curve, and source of heterogeneity analysis, through the MIDAS module in Stata 15. We performed meta-regression and subgroup analyses to analyze the sources of heterogeneity. Using the QUADAS-2 scale and the RQS scale to assess the quality of retrieved studies.

RESULTS

Ten studies with 6199 patients were finally included in our meta-analysis. Pooled sensitivity and specificity were 0.77 (95% confidence interval [CI]: 0.66, 0.86), and 0.88 (95% CI 0.80, 0.93), respectively. The overall AUC was 0.89 (95% CI 0.86, 0.92). The heterogeneity of this meta-analysis was high, with I2 = 88% (95% CI 75,100). The result of meta-regression showed that QUADAS-2 results, RQS results and machine learning method led to heterogeneity in sensitivity and specificity (P < 0.05). Furthermore, the image segmentation area and the presence or absence of combined clinical factors were associated with sensitivity heterogeneity and specificity heterogeneity, respectively.

CONCLUSION

Undoubtedly, radiomics has potential value in diagnosing peritoneal metastasis of gastric cancer, but the quality of current research is inconsistent, and more standardized and high-quality research is still needed in the future to achieve the transformation of radiomics results into clinical applications.

Peritoneal Cell-Free Tumor DNA is a Biomarker of Locoregional and Peritoneal Recurrence in Resected Pancreatic Ductal Adenocarcinomas

BACKGROUND

Recurrence after curative-intent pancreatectomy for pancreatic ductal adenocarcinomas (PDAC) is quite frequent with locoregional and peritoneal recurrence in about one-third of cases. We hypothesize that peritoneal cell-free tumor DNA (ptDNA) present in the intraoperative peritoneal lavage (PL) fluid may be used as a predictive biomarker of locoregional and peritoneal recurrence.

PATIENTS AND METHODS

Under institutional review board (IRB)-approved protocol, pre- and postresection PL fluids were collected from PDAC patients undergoing curative-intent pancreatectomy. PL fluids from PDAC patients with pathologically proven peritoneal metastasis were also collected as positive controls. Cell-free DNA was extracted from PL fluids. Droplet digital PCR (ddPCR) was performed using ddPCR KRAS G12/G13 screening kit. Recurrence-free survival (RFS) based on KRAS-mutant ptDNA level was determined using Kaplan-Meier methods.

RESULTS

KRAS-mutant ptDNA was detected in PL fluids from all PDAC patients. KRAS-mutant ptDNA was detected in 11/21 (52%) preresection and 15/18 (83%) postresection PL fluid samples. With a median follow-up of 23.6 months, 12 patients developed recurrence (8 locoregional/peritoneal recurrence, 9 pulmonary/hepatic recurrence); 5/8 (63%) and 6/6 (100%) patients with mutant allele frequency (MAF) of > 0.10% in pre- and postresection PL fluids, respectively, developed recurrence. Using a cutoff value of 0.10% MAF, the presence of KRAS-mutant ptDNA in postresection PL fluid predicted a significantly shortened time to locoregional and peritoneal recurrence (median RFS of 8.9 months versus not reached, P = 0.003).

CONCLUSIONS

This study suggests that ptDNA in postresection PL fluids may be a useful biomarker to predict locoregional and peritoneal recurrence in resected PDAC patients.

Morbimortality after 1321 consecutive CRS + HIPEC procedures: seeking excellence in surgery for peritoneal surface malignancy

PURPOSE

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) treatment has classically presented a percentage of associated complications that have limited its expansion. The aim of this study is to describe the morbimortality results obtained from a referral center implemented with the support of a governmental health agency and directed by a surgical team experienced in CRS for Peritoneal Surface Malignancies (PSM).

METHODS

Data from the Peritoneal Carcinomatosis Program of Catalonia (PCPC) prospective database, including patients who underwent CRS + HIPEC between September 2006 and January 2021, were analyzed.

RESULTS

A total of 1151 consecutive patients underwent 1321 CRS + HIPEC procedures. Colonic origin of peritoneal metastasis was the most frequent (47.3%). Median PCI was 7 and most patients had CC0-1 (96.1%). Multivisceral resection was performed in 44% of all patients, 57% required digestive anastomosis. Median hospital stay was 11 days (range 6-144 days). High-grade complications occurred in 20% of all patient, most of them surgical complications. Anastomotic leak occurred in 0.6% of all cases. The overall in-stay and 30-day mortality rate was 0.4%. The low-rate of complications and the high rate of complete CRS were achieved from the beginning of the PCPC. Median overall survival was 54.7 months, with a 5-year survival rate of 47.5%.

CONCLUSIONS

Implementation of a CRS + HIPEC referral program for the treatment of PSM with preferably an experienced surgical team enables acceptable rates of severe morbidity (20%) and mortality (< 1%).

Hyperthermic intraperitoneal chemotherapy (HIPEC) plus systemic chemotherapy versus systemic chemotherapy alone in locally advanced gastric cancer after D2 radical resection: a randomized-controlled study

BACKGROUND

Currently, there is a lack of an effective strategy for the prevention of peritoneal metastasis (PM) from locally advanced gastric cancer (AGC). This randomized-controlled study aimed to evaluate the outcome of D2 radical resection with hyperthermic intraperitoneal chemotherapy (HIPEC) plus systemic chemotherapy versus systemic chemotherapy alone in locally AGC patients.

METHODS

All enrolled patients were randomly assigned to receive HIPEC plus systemic chemotherapy (HIPEC group) or systemic chemotherapy alone (non-HIPEC group) after radical gastrectomy. HIPEC was performed intraperitoneally with cisplatin (40 mg/m2) within 72 h after surgery, while systemic chemotherapy based on the SOX regimen (S-1 combined with oxaliplatin) was administered 4-6 weeks after radical surgery. Patterns of recurrence, adverse events, 3-year disease-free survival (DFS), and overall survival (OS) were analyzed.

RESULTS

A total of 134 patients were enrolled in the present study. The 3-year DFS rate was 73.8% in the HIPEC group, which was significantly higher than that in the non-HIPEC group (61.2%, P = 0.031). The 3-year OS rate was 73.9% in the HIPEC group and 77.6% in the non-HIPEC group, with no significant difference (P = 0.737). PM was the most common distant metastasis in both groups. The occurrence rate of PM in the HIPEC group was statistically lower than that in the non-HIPEC group (20.9% vs. 40.3%, P = 0.015). Grade 3 or 4 adverse events occurred in 19 (14.2%) patients, and there was no significant difference between the two groups.

CONCLUSION

Radical surgery followed by HIPEC combined with systemic chemotherapy is a safe and feasible strategy for locally AGC patients and could effectively improve DFS and reduce the occurrence of PM. However, more prospective randomized studies with a large sample size are warranted.

TRIAL REGISTRATION

This study was registered with www.medresman.org.cn as ChiCTR2200055966 on 10/12/2016.

Clinical significance of intraperitoneal paclitaxel combined with systemic chemotherapy for gastric cancer with peritoneal metastasis

BACKGROUND

Despite investigations of intraperitoneal paclitaxel as a personalized treatment for peritoneal metastasis of gastric cancer, few studies have evaluated its prognostic impact on conversion surgery for unresectable gastric cancer with peritoneal metastasis. Our study aimed to close this gap in knowledge.

METHODS

We retrospectively enrolled 128 patients who underwent chemotherapy for peritoneal metastasis from gastric cancer and assigned them into intraperitoneal (IP) (n = 36) and non-IP (n = 92) groups, based on the use of intraperitoneal paclitaxel plus systemic chemotherapy.

RESULTS

Disease control rates were 94% and 69% in the IP and non-IP groups, respectively, with the former having a significantly higher tumor response rate than the latter (p < 0.01). The median survival times in the IP and non-IP groups were 665 and 359 days, respectively, with the former having significantly better prognosis than the latter (p = 0.02). Fifteen (42%) and sixteen (17%) patients underwent conversion surgery after chemotherapy in the IP and non-IP groups, respectively, with the former having a significantly higher conversion surgery induction rate than the latter (p < 0.01). Although the prognosis of the conversion surgery group was significantly better than that of the non-conversion surgery group (p < 0.01), there was no significant difference in prognosis between patients in the IP and non-IP groups who underwent conversion surgery (p = 0.22). Multivariate analysis identified performance status and conversion surgery as independent prognostic factors (all p < 0.01).

CONCLUSION

Our study demonstrated that the IP chemotherapy was one of important factors for conversion surgery induction, while it was not a risk factor for prognosis.

Efficacy and Safety of Extensive Intraperitoneal Lavage for Patients with Gastric Cancer - A Systematic Review and Meta-analysis

PURPOSE

Extensive  intraperitoneal lavage (EIPL) is a novel therapeutic intervention that aims to limit the chance of peritoneal metastasis during gastrectomy. Clinical trials on using EIPL after gastrectomy show controversial results. We aimed to summarize the evidence of efficacy and safety for using EIPL after gastrectomy to limit the possibility of peritoneal metastasis and improve survival.

METHODS

A literature search on PubMed, Scopus, Embase, and Web of Sciences was conducted till June 2023 to identify eligible RCTs that assess the efficacy and safety of EIPL after gastrectomy. The hazard ratio with 95% CI was used to determine the survival probability, the risk ratio with 95% CI was used to assess the surgical outcomes, and ROB-2 and GRADE guidelines were used to assess the risk of bias and the certainty of evidence respectively.

RESULTS

Six eligible studies with a total of 1993 patients were included in the meta-analysis. Regarding survival benefits, the survival of the EIPL group did not differ significantly from the non-EIPL group, and the pooled HR of overall survival was 0.86 (95% CI 0.58-1.26) P = 0.44, the disease-free survival was 0.81 (0.58-1.13) P = 0.21, and peritoneal recurrence-free survival was 0.97 (0.79-1.2) P = 0.25. There is no significant association between EIPL and short-term postoperative outcomes. The use of EIPL does not appear to affect postoperative mortality, infection, anastomotic leakage, bleeding, ileus, or hospital stay.

CONCLUSION

Our study yielded insufficient evidence about the survival benefits and surgical outcomes of EIPL in patients with gastric cancer after gastrectomy. Therefore, it is not recommended for treating gastric cancer patients.

Intraoperative Pathological Evaluation of Suspicious Peritoneal Nodules for Surgical Decision-making in Gastric Cancer

BACKGROUND

When frozen pathological results of suspicious peritoneal nodules found in gastric cancer (GC) patients are negative or indeterminant, whether to perform gastrectomy will always be a dilemma for surgeons. This study aimed to facilitate intraoperative surgical decision-making based on frozen section (FS) results and clinicopathological characteristics.

METHODS

From January 2015 to July 2021, 318 GC patients were enrolled retrospectively. The correlations between frozen and paraffin pathology of peritoneal nodules were examined. Then, predictive factors of positive paraffin section (PS) results were identified, and a nomogram was constructed. The survival significance of gastrectomy was also explored.

RESULTS

Of 70 FS-negative patients, 59 (84.3%) had concordant negative PS results, while the PS results of 11 (15.7%) were positive. Forty-six (93.9%) and 3 (6.1%) of 49 patients with indeterminant FS results had positive and negative PS results, respectively. The PS results of 95 FS-positive patients were all positive. A nomogram for predicting positive PS results was developed based on Lauren type, nodule distribution, and CA125. Gastrectomy for FS-negative patients improved survival compared to no gastrectomy (HR 0.26, 95% CI 0.11-0.62; P = 0.0012). Survival benefits for gastrectomy vs. no gastrectomy were not demonstrated in patients with indeterminant (HR 0.74, 95% CI 0.27-2.01; P = 0.53) and positive (HR 0.87, 95% CI 0.43-1.74; P = 0.69) FS results.

CONCLUSIONS

Gastrectomy can be justified for the treatment of operable GC patients with negative frozen pathological results of peritoneal nodules. For patients with positive and indeterminant frozen pathological results, gastrectomy is not recommended unless it is performed as palliative surgery.

Peritoneal metastasis of advanced epithelial ovarian carcinoma treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: A retrospective international multicentric data analysis

INTRODUCTION

The purpose of our study was to evaluate outcome data after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with peritoneal metastasis originating from advanced epithelial ovarian carcinoma (PMOC).

PATIENTS AND METHODS

A retrospective international multi-institutional registry was established through collaborative efforts of participating units affiliated with the Peritoneal Surface Oncology Group.

RESULTS

One thousand four hundred and ninety-one patients from 11 specialized units underwent CRS and HIPEC that of those 326 (21.9%) upfront surgeries, 504 (33.8%) interval surgery, and 661(44.3%) recurrent cases. Complete Cytoreduction(CC0/1) was achieved in 1213 patients (81.3%). Treatment -related mortality was 0.8%, major operative complications (Grades 3-5) was 25.1%. Factors associated with major operative complications include prior surgical score (PSS for recurrent cases; RC) PSS>2,p = 0.000), PCI(≤15, >15 cut-off level; p ≤ 0.000), completeness of cytoreduction (CC, p=0.000), high CA125 levels (>25 mg/dl), presence of ascites, high CRP (>5 mg/dl) levels and low albumin levels (below to 2.5 mg/dl) (p ≤ 0.05). The median survival was 58 months in upfront surgery(UFS), 60 months in interval surgery(IS), and 42 months in RC. The overall survival for five years was 45% for UFS, 37% for IS, 28% for RC cases. CCscore (p = 0.000), CA125, CRP and albumin levels (p ≤ 0.05) were predictors for progression free survival. PCI(p ≤ 0.000), major postoperative complications (p = 0.004), incomplete CRS(CC2/3)(p < 0.001), prior chemotherapy (hazard ratio [HR], 3-8; p < 0.001) and PSS>2 for RC were independent predictors of poor overall survival.

CONCLUSION

The combined treatment strategy for PMOC may be performed safely with acceptable morbidity and mortality in the specialized units.

Efficacy of palliative surgery for gastric cancer patients with peritoneal metastasis who still have residual peritoneal dissemination after chemotherapy

PURPOSE

Gastric cancer patients with peritoneal metastasis (PM) are generally treated with systemic chemotherapy. When PM has disappeared because of chemotherapy, radical gastrectomy (so-called conversion surgery) is usually performed. We have previously reported the efficacy of conversion surgery, but there are no reports examining the efficacy of palliative gastrectomy for patients with residual PM after chemotherapy. The purpose of this study was to investigate the efficacy of palliative surgery for gastric cancer patients with PM who still have residual peritoneal dissemination after chemotherapy.

METHODS

Twenty-five gastric cancer patients with PM confirmed by laparoscopy and who had received chemotherapy but who still had residual PM were included in this study. Among the 25 patients, palliative surgery was performed in 20 patients (PS group) and chemotherapy was continued in 5 patients (CTx group), and their therapeutic outcomes were compared.

RESULTS

In the PS group, total and distal gastrectomies were performed. Clavien-Dindo grade I postoperative complications occurred in two patients (10%). There were no treatment-related deaths. Postoperative chemotherapy was performed all cases. In the PS group, the median survival time (MST) reached 22.5 months, with 1- and 2-year overall survival (OS) rates of 95% and 45%, respectively, whereas in the CTx group, the MST was 15.8 months, and the 1- and 2-year OS rates were 60% and 0%, respectively. The PS group had significantly longer OS than the CTx group (P=0.044).

CONCLUSIONS

Palliative surgery is safe and may prolong survival in gastric cancer patients with residual PM after chemotherapy.

Proteomic profiling of gastric cancer with peritoneal metastasis identifies a protein signature associated with immune microenvironment and patient outcome

BACKGROUND

Peritoneal metastasis (PM) frequently occurs in patients with gastric cancer (GC) and is a major cause of mortality. Risk stratification for PM can optimize decision making in GC treatment.

METHODS

A total of 25 GC patients (13 with synchronous, 6 with metachronous PM and 6 PM-free) were included in this study. Quantitative proteomics by high-depth tandem mass tags labeling and whole-exome sequencing were conducted in primary GC and PM samples. Proteomic signature and prognostic model were established by machine learning algorithms in PM and PM-free GC, then validated in two external cohorts. Tumor-infiltrating immune cells in GC were analyzed by CIBERSORT.

RESULTS

Heterogeneity between paired primary and PM samples was observed at both genomic and proteomic levels. Compared to primary GC, proteome of PM samples was enriched in RNA binding and extracellular exosomes. 641 differently expressed proteins (DEPs) between primary GC of PM group and PM-free group were screened, which were enriched in extracellular exosome and cell adhesion pathways. Subsequently, a ten-protein signature was derived based on DEPs by machine learning. This signature was significantly associated with patient prognosis in internal cohort and two external proteomic datasets of diffuse and mixed type GC. Tumor-infiltrating immune cell analysis showed that the signature was associated with immune microenvironment of GC.

CONCLUSIONS

We characterized proteomic features that were informative for PM progression of GC. A protein signature associated with immune microenvironment and patient outcome was derived, and it could guide risk stratification and individualized treatment.

Galectin-1 promotes gastric cancer peritoneal metastasis through peritoneal fibrosis

BACKGROUND

Peritoneal metastasis is one of the main causes of death in patients with gastric cancer (GC). Galectin-1 regulates various undesirable biological behaviors in GC and may be key in GC peritoneal metastasis.

METHODS

In this study, we elucidated the regulatory role of galectin-1 in GC cell peritoneal metastasis. GC and peritoneal tissues underwent hematoxylin-eosin (HE), immunohistochemical (IHC), and Masson trichrome staining to analyze the difference in galectin-1 expression and peritoneal collagen deposition in different GC clinical stages. The regulatory role of galectin-1 in GC cell adhesion to mesenchymal cells and in collagen expression was determined using HMrSV5 human peritoneal mesothelial cells (HPMCs). Collagen and corresponding mRNA expression were detected with western blotting and reverse transcription PCR, respectively. The promoting effect of galectin-1 on GC peritoneal metastasis was verified in vivo. Collagen deposition and collagen I, collagen III, and fibronectin 1 (FN1) expression in the peritoneum of the animal models were detected by Masson trichrome and IHC staining.

RESULTS

Galectin-1 and collagen deposition in the peritoneal tissues was correlated with GC clinical staging and were positively correlated. Galectin-1 enhanced the ability of GC cells to adhere to the HMrSV5 cells by promoting collagen I, collagen III, and FN1 expression. The in vivo experiments confirmed that galectin-1 promoted GC peritoneal metastasis by promoting peritoneal collagen deposition.

CONCLUSION

Galectin-1-induced peritoneal fibrosis may create a favorable environment for GC cell peritoneal metastasis.

Comparison of genetic variation between primary colorectal cancer and metastatic peritoneal cancer

BACKGROUND

Among cancer metastases by primary colorectal cancer (CRC), peritoneal metastasis is the second most common metastatic lesion after liver metastasis. In treating metastatic CRC, it is very important to differentiate targeted-therapy and chemotherapy according to the characteristics of each lesion because the genetic variation of the primary and metastatic lesions are different. However, there are few studies of genetic characteristics on peritoneal metastasis caused by primary CRC, so molecular-level studies are continuously required.

OBJECTIVE

We propose an appropriate peritoneal metastasis treatment policy by identifying the genetic characteristics between primary CRC and synchronous peritoneal metastatic lesions.

METHODS

Primary CRC and synchronous peritoneal metastasis samples were analyzed in pairs from six patients using Comprehensive Cancer Panel (409 cancer-related genes, Thermo Fisher Scientific, USA) and next-generation sequencing (NGS).

RESULTS

The mutations were commonly found on the KMT2C and THBS1 genes in both primary CRC and peritoneal metastasis. The PDE4DIP gene was mutated in all cases except for on a sample of peritoneal metastasis. As a result of analysis using the mutation database, we confirmed that the gene mutations of primary CRC and the peritoneal metastasis derived from it showed the same tendency, although we did not accompany the gene expression level or epigenetic study.

CONCLUSION

It is thought that the treatment policy through molecular genetic testing of primary CRC can also be applied to peritoneal metastasis treatment. Our study is expected to be the basis for further peritoneal metastasis research.

Prolonged hyperthermic intraperitoneal chemotherapy duration with 90 minutes cisplatin might increase overall survival in gastric cancer patients with peritoneal metastases

BACKGROUND

Advanced gastric cancer with synchronous peritoneal metastases (GC-PM) is associated with a poor prognosis. Although cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is a promising approach, only a limited number of Western studies exist.

AIM

To investigate the clinicopathological outcomes of patients who underwent CRS-HIPEC for GC-PM.

METHODS

A retrospective analysis of patients with GC-PM was conducted. All patients were seen at the Department of General and Visceral Surgery, Hospital Barmherzige Brüder, Regensburg, Germany between January 2011 and July 2021 and underwent CRS-HIPEC. Preoperative laboratory results, the use of neoadjuvant trastuzumab, and the details of CRS-HIPEC, including peritoneal carcinomatosis index, completeness of cytoreduction, and surgical procedures were recorded. Disease-specific (DSS), and overall survival (OS) of patients were calculated.

RESULTS

A total of 73 patients were included in the study. Patients treated with neoadjuvant trastuzumab (n = 5) showed longer DSS (P = 0.0482). Higher white blood cell counts (DSS: P = 0.0433) and carcinoembryonic antigen levels (OS and DSS: P < 0.01), and lower hemoglobin (OS and DSS: P < 0.05) and serum total protein (OS: P = 0.0368) levels were associated with shorter survival. Longer HIPEC duration was associated with more advantageous median survival times [60-min (n = 59): 12.86 mo; 90-min (n = 14): 27.30 mo], but without statistical difference. To obtain additional data from this observation, further separation of the study population was performed. First, propensity score-matched patient pairs (n = 14 in each group) were created. Statistically different DSS was found between patient pairs (hazard ratio = 0.2843; 95% confidence interval: 0.1119-0.7222; P = 0.0082). Second, those patients who were treated with trastuzumab and/or had human epidermal growth factor receptor 2 positivity (median survival: 12.68 mo vs 24.02 mo), or had to undergo the procedure before 2016 (median survival: 12.68 mo vs 27.30 mo; P = 0.0493) were removed from the original study population.

CONCLUSION

Based on our experience, CRS-HIPEC is a safe and secure method to improve the survival of advanced GC-PM patients. Prolonged HIPEC duration may serve as a good therapy for these patients.

Towards an optimal model for gastric cancer peritoneal metastasis: current challenges and future directions

Peritoneal metastasis is a challenging aspect of clinical practice for gastric cancer. Animal models are crucial in understanding molecular mechanisms, assessing drug efficacy, and conducting clinical intervention studies, including those related to gastric cancer peritoneal metastasis. Unlike other xenograft models, peritoneal metastasis models should not only present tumor growth at the transplant site, but also recapitulate tumor cell metastasis in the abdominal cavity. Developing a reliable model of gastric cancer peritoneal metastasis involves several technical aspects, such as the selection of model animals, source of xenograft tumors, technology of transplantation, and dynamic monitoring of the tumor progression. To date, challenges remain in developing a reliable model that can completely recapitulate peritoneal metastasis. Thus, this review aims to summarize the techniques and strategies used to establish animal models of gastric cancer peritoneal metastasis, providing a reference for future model establishment.

Intraperitoneal seeding of a testicular mixed germ cell tumor following spontaneous intraperitoneal mass rupture with associated anti-NMDA paraneoplastic encephalitis

A 25-year-old male was admitted to the neurological intensive care unit for neurologic deterioration, likely caused by a paraneoplastic syndrome secondary to testicular malignancy. He experienced spontaneous rupture and hemorrhage of his testicular mass arising from an undescended testis while admitted. The tumor was excised, revealing a mixed germ cell tumor. Serum tumor markers began to rise after 4 cycles of chemotherapy. Surveillance scans 32 weeks after mass rupture revealed numerous tumor deposits throughout his peritoneum concerning for teratoma. We review a case of intraperitoneal metastasis of a testicular mixed germ cell tumor following intra-abdominal mass rupture.

Can visceral fat parameters based on computed tomography be used to predict occult peritoneal metastasis in gastric cancer?

BACKGROUND

The preoperative prediction of peritoneal metastasis (PM) in gastric cancer would prevent unnecessary surgery and promptly indicate an appropriate treatment plan.

AIM

To explore the predictive value of visceral fat (VF) parameters obtained from preoperative computed tomography (CT) images for occult PM and to develop an individualized model for predicting occult PM in patients with gastric carcinoma (GC).

METHODS

A total of 128 confirmed GC cases (84 male and 44 female patients) that underwent CT scans were analyzed and categorized into PM-positive (n = 43) and PM-negative (n = 85) groups. The clinical characteristics and VF parameters of two regions of interest (ROIs) were collected. Univariate and stratified analyses based on VF volume were performed to screen for predictive characteristics for occult PM. Prediction models with and without VF parameters were established by multivariable logistic regression analysis.

RESULTS

The mean attenuations of VF_{ROI 1} and VF_{ROI 2} varied significantly between the PM-positive and PM-negative groups (P = 0.044 and 0.001, respectively). The areas under the receiver operating characteristic curves (AUCs) of VF_{ROI 1} and VF_{ROI 2} were 0.599 and 0.657, respectively. The mean attenuation of VF_{ROI 2} was included in the final prediction combined model, but not an independent risk factor of PM (P = 0.068). No significant difference was observed between the models with and without mean attenuation of VF (AUC: 0.749 vs 0.730, P = 0.339).

CONCLUSION

The mean attenuation of VF is a potential auxiliary parameter for predicting occult PM in patients with GC.

Effect of adjuvant chemotherapy after curative resection of colorectal cancer peritoneal metastasis

PURPOSE

Several guidelines have recommended surgical resection for localized peritoneal metastases, but the prognosis remains poor. In addition, the efficacy of adjuvant chemotherapy (AC) after curative resection is under debate. The present study compared long-term outcomes between curative and non-curative resection and evaluated the effects of AC after curative resection.

METHODS

Using a multicenter database, we retrospectively reviewed 123 colorectal cancer patients with peritoneal metastases between April 2016 and December 2021. Of these patients, 49 underwent curative resection, and 74 underwent non-curative resection.

RESULTS

The frequency of broad metastases was lower in the curative resection group (8.2%) than in the non-curative resection group (43.2%, p < 0.001). Among all patients, 5-year overall survival rate was higher in the curative resection group (43.0%) than in the non-curative resection group (7.3%, p = 0.004). Among patients who underwent curative resection, 5-year overall survival rate was significantly higher in the AC group (48.2%) than in the non-AC group (38.1%, p = 0.037). Multivariate analysis of all patients revealed pathological N status and non-curative resection as independent predictors of overall survival. In patients who underwent curative resection, advanced age was an independent predictor of relapse-free survival, and AC was an independent predictor of overall survival.

CONCLUSION

This multicenter study of colorectal cancer patients with peritoneal metastases revealed that prognosis was more favorable for curable cases than for non-curable cases. Prognosis was more favorable in the AC group than in the non-AC group after curative resection.

Peritoneal cell-free DNA as a sensitive biomarker for detection of peritoneal metastasis in colorectal cancer: a prospective diagnostic study: A prospective diagnostic study

BACKGROUND

The detection of peritoneal metastasis (PM) is limited by current imaging tools. In this prospective study, we aimed to evaluate the sensitivity and specificity of peritoneal cell-free DNA (cfDNA) for diagnosis of PM.

METHODS

Colorectal cancer (CRC) patients with/without PM were enrolled. The cfDNA experimental personnel and statists were blinded to the diagnosis of PM. Ultradeep sequencing covering large genomic regions (35000X, Next-generation sequencing) of cfDNA in peritoneal lavage fluid (FLD) and matched tumor tissues was performed.

RESULTS

A total of 64 cases were recruited prospectively and 51 were enrolled into final analysis. In training cohort, 100% (17/17) PM patients obtained positive FLD cfDNA, comparing to 5/23 (21.7%) in patients without PM. Peritoneal cfDNA had a high sensitivity of 100% and specificity of 77.3% for diagnosis of PM (AUC: 0.95). In validation group of 11, 5/6 (83%) patients with PM obtained positive FLD cfDNA, comparing to 0/5 in non-PM (P = 0.031) with a sensitivity of 83.3% and specificity of 100%. Positive FLD cfDNA was associated with poor recurrence-free survival (P = 0.013) and was preceding radiographic evidence of recurrence.

CONCLUSIONS

Peritoneal cfDNA is a promising sensitive biomarker for earlier detection of PM in CRC than current radiological tools. It can potentially guide selection for targeted therapies and serve as a surrogate instead of laparoscopic explore in the future. Trial Registration Chinese Clinical Trial Registry at chictr.org.cn (ChiCTR2000035400). URL: http://www.chictr.org.cn/showproj.aspx?proj=57626.

HIPEC with CRS versus cytoreductive surgery (CRS) for the gastric cancer metastasis to peritoneum

BACKGROUND

Peritoneal metastases (PM) have a poor prognosis in gastric cancer (GC). Cytoreductive surgery (CRS) gives favorable outcomes, but the influence of hyperthermic intraperitoneal chemotherapy (HIPEC) remains contentious. We designed to distinguish results between CRS versus HIPEC-CRS in patients with peritoneal metastases from gastric cancer.

MATERIALS AND METHODS

PubMed, Scopus, Embase and Cochrane library accessed to collect data and language is restricted to English. RevMan 5.4 was used to perform statistical analysis. The outcomes for categorical variables are mentioned in the risk ratio.

RESULTS

Ten trials involving 1367 patients in which 707 were CRS-HIPEC, while 660 CRS. We got significant results in 3rd year survival (P < 0.05), while 1st and 5th years are not statistically significant P > 0.05.

CONCLUSION

To compare with CRS, CRS-HIPEC has improved survival rate in deprived of further morbidity or mortality.

Separation and single-cell analysis for free gastric cancer cells in ascites and peritoneal lavages based on microfluidic chips

BACKGROUNDS

Detecting free cancer cells from ascites and peritoneal lavages is crucial for diagnosing gastric cancer (GC). However, traditional methods are limited for early-stage diagnosis due to their low sensitivity.

METHODS

A label-free, rapid, and high-throughput technique was developed for separating cancer cells from ascites and peritoneal lavages using an integrated microfluidic device, taking advantage of dean flow fractionation and deterministic lateral displacement. Afterward, separated cells were analyzed using a microfluidic single-cell trapping array chip (SCTA-chip). In situ immunofluorescence for EpCAM, YAP-1, HER-2, CD45 molecular expressions, and Wright-Giemsa staining were performed for cells in SCTA-chips. At last, YAP1 and HER-2 expression in tissues was analyzed by immunohistochemistry.

FINDINGS

Through integrated microfluidic device, cancer cells were successfully separated from simulated peritoneal lavages containing 1/10,000 cancer cells with recovery rate of 84.8% and purity of 72.4%. Afterward, cancer cells were isolated from 12 patients' ascites samples. Cytological examinations showed cancer cells were efficiently enriched with background cells excluded. Afterwards, separated cells from ascites were analyzed by SCTA-chips, and recognized as cancer cells through EpCAM⁺/CD45^- expression and Wright-Giemsa staining. Interestingly, 8 out of 12 ascites samples showed HER-2⁺ cancer cells. At last, the results through a serial expression analysis showed that YAP1 and HER-2 have discordant expression during metastasis.

INTERPRETATION

Microfluidic Chips developed in our study could not only rapidly detect label-free free GC cells in ascites and peritoneal lavages with high-throughput, they could also analyze ascites cancer cells at the single-cell level, improving peritoneal metastasis diagnosis and investigation of therapeutic targets.

FUNDING

This research was supported by National Natural Science Foundation of China (22134004, U1908207, 91859111); Natural Science Foundation of Shandong Province of China (ZR2019JQ06); Taishan Scholars Program of Shandong Province tsqn (201909077); Local Science and Technology Development Fund Guided by the Central Government (YDZX20203700002568); Applied Basic Research Program of Liaoning Province (2022020284-JH2/1013).

Palliative Care and Characterization of Symptoms in Patients Undergoing Cytoreductive Surgery/Hyperthermic Intraperitoneal Chemotherapy

INTRODUCTION

Palliative care for advanced cancer patients has been associated with improvements in symptom management and quality of life (QoL). Patients with peritoneal metastases undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) often report symptoms adversely affecting QoL. We characterized and compared symptoms elucidated by palliative care versus surgical providers in this setting.

METHODS

CRS/HIPEC patients who saw both surgical oncology and palliative care providers from 2016 to 2020 at a tertiary care center were identified from a retrospective database. Documentation of QoL-associated symptoms in surgical oncology and palliative care visits was recorded and analyzed.

RESULTS

A total of 118 patients were included in this study. The most common primary histologies were appendiceal (36.4%) and colorectal (28.8%). Symptoms most frequently reported by palliative care were pain (60.2%) and fatigue (54.2%). The median number of symptoms documented was three (2, 5) in palliative care notes and two (0, 3) in surgical oncology notes (P < 0.001). Palliative care providers documented most symptoms statistically more frequently than surgical oncology providers.

CONCLUSIONS

Patients who underwent CRS/HIPEC experienced various QoL-associated symptoms. Palliative care providers elicited more symptoms than surgical oncology providers. Additional studies are needed to explore the impact on outcomes of perioperative palliative care in this challenging patient population.

One biopsy, two tumors: A case report of collision tumor consisting in breast and endometrioid carcinoma detected on bioptic sample of peritoneal carcinomatosis

Collision tumors are rare and very few cases were described in which collision was revealed in a metastatic lesion. Herein we report a case of woman with a peritoneal carcinomatosis underwent to bioptic procedure in correspondence of a nodule of Douglas peritoneum with clinical suspect of ovarian/uterine origin. Histologic examination revealed two different colliding epithelial neoplasms: an endometrioid carcinoma and a ductal breast carcinoma, the latter not suspected at the time of biopsy. Morphology and immunohistochemistry, in particular GATA3 and PAX8, defined clearly the two different colliding carcinomas.

miR-199a-3p promotes gastric cancer progression by promoting its stemness potential via DDR2 mediation

BACKGROUND

Peritoneal metastasis (PM) is an independent prognostic factor in gastric cancer (GC), however, the underlying mechanisms of PM occurrence remain unclear.

METHOD

The roles of DDR2 were investigated in GC and its potential relationship to PM, and orthotopic implants into nude mice were performed to assess the biological effects of DDR2 on PM.

RESULTS

Herein, DDR2 level is more significantly observed to elevate in PM lesion than the primary lesion. GC with DDR2-high expression evokes a worse overall survival (OS) in TCGA, similar results of the gloomy OS with high DDR2 levels are clarified via the stratifying stage of TNM. The conspicuously increased expression of DDR2 was found in GC cell lines, luciferase reporter assays verified that miR-199a-3p directly targeted DDR2 gene, which was correlated to tumor progression. We ulteriorly observed DDR2 participated in GC stemness maintenance via mediating pluripotency factor SOX2 expression and implicated in autophagy and DNA damage of cancer stem cells (CSCs). In particular, DDR2 dominated EMT programming through recruiting NFATc1-SOX2 complex to Snai1 in governing cell progression, controlling by DDR2-mTOR-SOX2 axis in SGC-7901 CSCs. Furthermore, DDR2 promoted the tumor peritoneal dissemination in gastric xenograft mouse model.

CONCLUSION

Phenotype screens and disseminated verifications incriminating in GC exposit the miR-199a-3p-DDR2-mTOR-SOX2 axis as a clinically actionable target for tumor PM progression. The herein-reported DDR2-based underlying axis in GC represents novel and potent tools for studying the mechanisms of PM.

Construction of a nomogram model for predicting peritoneal metastasis in gastric cancer: focused on cardiophrenic angle lymph node features

BACKGROUND

A different treatment was used when peritoneal metastases (PM) occurred in patients with gastric cancer (GC). Certain cancers' peritoneal metastasis could be predicted by the cardiophrenic angle lymph node (CALN). This study aimed to establish a predictive model for PM of gastric cancer based on the CALN.

METHODS

Our center retrospectively analyzed all GC patients between January 2017 and October 2019. Pre-surgery computed tomography (CT) scans were performed on all patients. The clinicopathological and CALN features were recorded. PM risk factors were identified via univariate and multivariate logistic regression analyses. The receiver operator characteristic (ROC) curves were generated using these CALN values. Using the calibration plot, the model fit was assessed. A decision curve analysis (DCA) was conducted to assess the clinical utility.

RESULTS

126 of 483 (26.1%) patients were confirmed as having peritoneal metastasis. These relevant factors were associated with PM: age, sex, T stage, N stage, enlarged retroperitoneal lymph nodes (ERLN), CALN, the long diameter of the largest CALN (LD of LCALN), the short diameter of the largest CALN (SD of LCALN), and the number of CALNs (N of CALNs). The multivariate analysis illustrated that the LD of LCALN (OR = 2.752, p < 0.001) was PM's independent risk factor in GC patients. The area under the curve (AUC) of the model was 0.907 (95% CI 0.872-0.941), demonstrating good performance in the predictive value of PM. There is excellent calibration evident from the calibration plot, which is close to the diagonal. The DCA was presented for the nomogram.

CONCLUSION

CALN could predict gastric cancer peritoneal metastasis. The model in this study provided a powerful predictive tool for determining PM in GC patients and helping clinicians allocate treatment.