Peritoneal Metastatic Lesions Research Articles

CD8 + T-cells restrict the development of peritoneal metastasis and support the efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC)

Multimodal therapy for peritoneal metastasis (PM) including cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) provides long-term survival in highly selected colorectal cancer patients. Mechanisms behind HIPEC are unknown and may include induction of adaptive immunity. We therefore analyzed human PM samples and explored the impact of HIPEC in experimental models. Human samples from colorectal primary tumors (n = 19) and PM lesions (n = 37) were examined for the presence of CD8 + T-cells and their association with disease free (DFS) and overall survival (OS). CD8 + T cell response after HIPEC was assessed using an in-vivo PM mouse model, tumor cell lines and patient-derived tumor organoids. Patients with high intraepithelial CD8 + T cell counts showed longer DFS and OS. In the mouse model, HIPEC controlled growth of PM and increased numbers of functional granzyme positive CD8 + T cells within tumors. Cell lines and human organoids that were treated with heated chemotherapies showed immunogenic changes, reflected by significantly higher levels of MHC-class I molecules and expression of Cancer Testis Antigens Cyclin A1 and SSX-4. Using in-vitro co-culture assays, we noticed that cancer cells treated with heated chemotherapy primed dendritic cells, which subsequently enhanced effector functions of CD8 + T cells. The presence of CD8 + T-cells within PM lesions is associated with prolonged survival of patients with PM. Data from PM mouse model and in-vitro assay show that heated chemotherapies induce immunogenic changes on cancer cells leading to induction of CD8 + T-cells mediated immunity, which seems to control growth of PM lesions in mice after HIPEC.

Evaluation of 68Ga-FAPI PET/CT and 18F-FDG PET/CT for the diagnosis of recurrent colorectal cancers

ObjectiveThe present study aimed to compare the diagnostic value of gallium-68-labeled fibroblast activation protein inhibitor positron emission tomography/computed tomography (68Ga-FAPI PET/CT) and fluorine-18-labeled fluorodeoxyglucose PET/CT (18F-FDG PET/CT) for detecting recurrent colorectal cancers (CRCs). Materials and MethodsFifty-six patients (age: 18–80 years, 31 men and 25 women) with suspected recurrent CRC were enrolled and underwent 18F-FDG PET/CT and 68Ga-FAPI PET/CT sequentially within 1 week. The maximum standard uptake value (SUVmax), tumor-to-background ratio (TBR), and diagnostic accuracy were estimated and compared between the two modalities by using Student’s t-test. The Wilcoxon signed-rank test was used to compare peritoneal carcinoma index (PCI) scores between the two imaging modalities. Results68Ga-FAPI PET/CT showed higher sensitivity for detecting recurrence (93 % vs. 79 %); lymph node metastasis (89 % vs. 78 %), particularly peritoneal lymph node metastasis (92 % vs. 63 %); and metastatic implantation on the intestinal wall (100 % vs. 25 %) compared to 18F-FDG PET/CT. However, 68Ga-FAPI PET/CT showed lower sensitivity for detecting bone metastasis (67 % vs. 100 %). The mean SUVmax values of peritoneal metastases and metastatic implantation on the intestinal wall were 4.28 ± 2.70 and 7.58 ± 1.66 for 18F-FDG PET/CT and 5.66 ± 1.97 and 6.70 ± 0.25 for 68Ga-FAPI PET/CT, respectively. Furthermore, 68Ga-FAPI PET/CT showed significantly higher TBR for peritoneal metastatic lesions (4.22 ± 1.47 vs. 1.41 ± 0.89, p < 0.0001) and metastatic implantation on the intestinal wall (5.63 ± 1.24 vs. 2.20 ± 0.5, p = 0.02) compared to 18F-FDG PET/CT. For the same patient, 68Ga-FAPI PET/CT yielded a more accurate PCI score and a greater area under the curve value for the receiver operating characteristic curve (p < 0.01) than 18F-FDG PET/CT. Conclusion68Ga-FAPI PET/CT was superior to 18F-FDG PET/CT for detecting recurrence and peritoneal metastases. Hence, we propose the combination of these two modalities for better clinical diagnosis and management of patients with CRC.

68Ga-FAPI-04 positron emission tomography/CT and laparoscopy for the diagnosis of occult peritoneal metastasis in newly diagnosed locally advanced gastric cancer: study protocol of a single-centre prospective cohort study

IntroductionAccurate baseline clinical staging is critical to inform treatment decision-making for patients with gastric cancers. Peritoneal metastasis (PM) is the most common form of metastasis in gastric cancer and mainly...

Tumor-mesothelium HOXA11-PDGF BB/TGF β1-miR-181a-5p-Egr1 feedforward amplifier circuity propels mesothelial fibrosis and peritoneal metastasis of gastric cancer.

A proportion of gastric cancer (GC) patients suffer from peritoneal metastasis (PM) in the late stage of tumor and these patients have a poor prognosis. To provide more care for GC patient with PM, a deeper exploration of the molecular characteristics of GC-PM is needed. Here we performed the in vitro and in vivo study to illustrate the effect of HOXA11 over-expressed GC cells on peritoneal mesothelial cells (HMrSV5), transcriptomics analyses of HMrSV5 cells co-cultured with HOXA11 over-expressed GC cells, counterparts or alone, cytokine array analyses of serum-free culture medium of HOXA11 over-expressed GC cells, we validated our findings through genetic manipulation of HMrSV5 cells and neutralizing antibodies targeting cytokines secreted by HOXA11 over-expressed GC cells in vitro, as well as utilized human peritoneal metastatic lesions to validate expression of potential targets. We identified that HOXA11 over-expressed GC cells strongly propelled mesothelial fibrosis in vivo and in vitro, and HOXA11 regulated paracrine and autocrine of PDGF BB and TGF β1 in GC cells to propel mesothelial fibrosis. Meanwhile, HOXA11 over-expressed GC cells drove PDGF BB and TGF β1 secretion to activate developmental-process related genes in HMrSV5 cells, including Egr1, which processes dependent on miR-181a-5p. Then, Egr1 could mediate peritoneal mesothelial fibrosis. Correspondingly, Egr1 over-expressed HMrSV5 cells supported migration and peritoneal dissemination of GC cells. Together our results suggest that a feedforward amplifier circuity governing GC cells and mesothelial cells in peritoneum contribute to peritoneal metastasis of GC cells.

HSF-1/miR-145-5p transcriptional axis enhances hyperthermic intraperitoneal chemotherapy efficacy on peritoneal ovarian carcinosis

Hyperthermic intraperitoneal administration of chemotherapy (HIPEC) increases local drug concentrations and reduces systemic side effects associated with prolonged adjuvant intraperitoneal exposure in patients affected by either peritoneal malignancies or metastatic diseases originating from gastric, colon, kidney, and ovarian primary tumors. Mechanistically, the anticancer effects of HIPEC have been poorly explored. Herein we documented that HIPEC treatment promoted miR-145-5p expression paired with a significant downregulation of its oncogenic target genes c-MYC, EGFR, OCT4, and MUC1 in a pilot cohort of patients with ovarian peritoneal metastatic lesions. RNA sequencing analyses of ovarian peritoneal metastatic nodules from HIPEC treated patients unveils HSF-1 as a transcriptional regulator factor of miR-145-5p expression. Notably, either depletion of HSF-1 expression or chemical inhibition of its transcriptional activity impaired miR-145-5p tumor suppressor activity and the response to cisplatin in ovarian cancer cell lines incubated at 42 °C. In aggregate, our findings highlight a novel transcriptional network involving HSF-1, miR145-5p, MYC, EGFR, MUC1, and OCT4 whose proper activity contributes to HIPEC anticancer efficacy in the treatment of ovarian metastatic peritoneal lesions.

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

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

BGN/FAP/STAT3 positive feedback loop mediated mutual interaction between tumor cells and mesothelial cells contributes to peritoneal metastasis of gastric cancer.

Peritoneal metastasis (PM) is most frequent in gastric cancer (GC) and cancer-associated fibroblasts (CAFs) play a critical role in this process. However, the concrete mechanism of crosstalk between CAFs and cancer cells in PM of GC remains unclear. Microarray sequencing of GC focus and PM lesions was performed, and biglycan (BGN) was screened for further study. Clinically, BGN expression was higher in GC tissues than adjacent normal tissues, and high expression correlated with poor prognosis. In vitro experiments demonstrated that BGN promoted tumor progression and the transformation of mesothelial cells (MCs) into cancer-associated fibroblasts like cells (CAFLCs). In turn, CAFLCs-derived fibroblast activation protein (FAP) facilitated the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of GC cells. GC-derived BGN combined with toll like receptor 2 (TLR2)/TLR4 on MCs to activate the NF-κB pathway and promote the transformation of MCs into CAFLCs by the recovery experiment, coimmunoprecipitation assay, nuclear and cytoplasmic protein extraction assay. CAFLCs-derived FAP could activate the JAK2/STAT3 signaling pathway in GC. Finally, activated STAT3 promoted BGN transcription in GC, resulting in a BGN/FAP-STAT3 positive feedback loop. Taken together, mutual interaction between tumor cells and activated MCs mediated by a BGN/FAP-STAT3 positive feedback loop facilitates PM of GC and provides a potential biomarker and therapeutic target for GC metastasis.

Comprehensive analysis of m6A-modified circRNAs in peritoneal metastasis of high grade serious carcinoma of ovary.

PurposeHigh-grade serous ovarian cancer (HGSOC) remains the most lethal female cancer due to metastasis. CircRNAs are recently identified to be modified by N6-methyladenosine (m6A) in many cells. However, the significance of m6A-modified circular RNAs (circRNAs) has not been elucidated in HGSOC peritoneal metastasis. Here, we aimed to investigate the participation and potential functions of m6A-modified circRNAs in HGSCO peritoneal metastasis.MethodsCancerous tissues were collected from the in situ and the peritoneal metastasis lesions of HGSCO patients. M6A-tagged circRNAs were identified by m6A-modified RNA immunoprecipitation sequencing (m6A-RIP-seq). Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to predict the potential functions of the m6A-modified circRNAs.ResultsFor the m6A-modified circRNAs, 259 were upregulated and 227 were downregulated in the peritoneal metastasis than in the situ lesions of HGSCO patients. For the m6A peaks, 1541 were upregulated and 1293 were downregulated in the peritoneal metastasis than in the in situ lesions of HGSCO patients. For the differential expressed circRNAs, 1911(19.6%) were upregulated and 2883(29.6%) were downregulated in the peritoneal metastasis than in the in situ lesions of HGSCO patients. The upregulated m6A-modified circRNAs were associated with the HIF-1 signaling. The downregulated m6A-modified circRNAs were associated with the MAPK signaling.ConclusionsThis work firstly identified the transcriptome-wide map of m6A-modified circRNAs in peritoneal metastasis of HGSCO. Our findings provided novel evidences about the participation of m6A-modified circRNAs via HIF-1 and MAPK signaling and a new insight in molecular target of HGSCO peritoneal metastasis.

Hypoxia-Induced CD36 Expression in Gastric Cancer Cells Promotes Peritoneal Metastasis via Fatty Acid Uptake

BackgroundThe lipid scavenger receptor cluster of differentiation 36 (CD36) has been shown to have a pro-metastatic function in several cancers. Adipose tissue, a favorable site for peritoneal metastasis (PM) from gastric cancer (GC), promotes this process by providing free fatty acids (FFAs); however, the role of CD36 in PM progression from GC remains to be elucidated.Materials and MethodsWe evaluated CD36 expression in the GC cells under various conditions. CD36 overexpressing (CD36OE) MKN45 cells were prepared and their migration and invasive properties were assessed. A PM mouse model was used to investigate the biological effects of palmitic acid (PA) and CD36. Furthermore, we examined the clinical role of CD36 expression in 82 human PM samples by immunohistochemical staining.ResultsHypoxia markedly increased CD36 expression in GC cells. In normoxia, only CD36OE MKN45 cells treated with PA showed an increase in migration and invasion abilities. An increased expression of active Rac1 and Cdc42 was observed, which decreased following etomoxir treatment. Conversely, hypoxia increased those capacities of both vector and CD36OE MKN45 cells. In a mouse model transplanted with CD36OE MKN45 cells, more peritoneal tumors were observed in the high-fat diet group than those in the normal diet group. In clinical samples, 80% of PM lesions expressed CD36, consistent with hypoxic regions, indicating a significant association with prognosis.ConclusionOur findings indicate that a hypoxia in the peritoneal cavity induces CD36 expression in GC cells, which contributes to PM through the uptake of FFAs.

Global multi-center phase I trial of the intraperitoneal infusion of anti-EpCAM x anti-CD3 bispecific antibody catumaxomab for advanced gastric carcinoma with peritoneal metastasis.

e16102 Background: Advanced gastric cancer (GC) patients (pts) have high incidence of peritoneal metastasis (PM), resulting in ascites, cachexia and poor life quality. EpCAM is highly expressed on GC but no on peritoneum. Catumaxomab intraperitoneal infusion (i.p.) was previously demonstrated to eradicate EpCAM+ cancers and control the malignant ascites in Europe (Heiss. Int. J. Cancer.2010). We present initial safety, pharmacokinetics (PK), and efficacy from the multi-center phase I trial of Catumaxomab on GC pts with PM in Asian population (NCT04222114). Methods: GC pts who had progressed on at least two prior standard systemic therapies with peritoneal metastasis were enrolled. Pts received Catumaxomab i.p. of 10 μg, 20 μg, 50 μg and 150 μg on days 1, 4, 8 and 11, respectively in the 1st cycle. From the 2nd cycle, Pts received Catumaxomab i.p. of 20 μg, 50 μg, 150 μg on days 1, 4 and 8, respectively. The cycle was 42 days in Cohort A, and 28 days in Cohort B. Catumaxomab PK were evaluated, tumor measurements and quantification of ascites by five-point method (Oriuchi, JJCO,2005) were performed Q6W. The primary endpoint was overall survival (OS); secondary endpoints were response rate of ascites, progression-free interval of peritoneal metastatic lesions and puncture-free survival (PuFS); Data cut-off date was Jan 29,2022. Results: 17 pts from 14 sites (median age: 52.5 yr, ECOG PS: 0 [n=2], 1 [n=14], 2[n=1], Cohort A:9, Cohort B:8) were treated. There were no dose-limiting toxicities (DLTs). The most common treatment-emergent adverse event (TEAE) was pyrexia (76.5%) and abdominal pain (58.8%). Grade ≥3 treatment related adverse events (TRAE) of abdominal pain (23.5%), bilirubin conjugated increased (23.5%), lymphocyte count decreased (17.6%), ALT increased (11.8%), and AST increased (11.8%) were reported. No treatment related death or neurotoxicity occurred in the study. Median overall survival was 102 days (95%CI: 38-166), with 10 (58.8%) deaths observed. For ascites, CR+PR was observed in 4 cases (33%), no PD case was reported. No therapeutic ascites drainage was recorded after cycle 1. Median PuFS was 116 days (95%CI: 28-157). Median progression-free interval of peritoneal metastatic lesions was 102 days (95%CI: 38-166). PK: Catumaxomab concentrations in plasma increased in a dose-dependent manner and were similar to Caucasian population in Europe. Conclusions: This clinical study indicated that multiple cycles of Catumaxomab i.p. were safe and well tolerated in Asian population. PK profile was similar. Early efficacy signals were promising, especially in pts with ascites, which will be further investigated in phase 3 study. Clinical trial information: NCT04222114.

Effect of Systemic or Intraperitoneal Administration of Anti-PD-1 Antibody for Peritoneal Metastases from Gastric Cancer.

Programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) blockade therapy is widely used for the treatment of patients with metastatic gastric cancer (GC). However, it is unclear how PD-1 antibodies affect the local immunity related to the growth of peritoneal metastases (PM). The clinical efficacy of PD-1/PD-L1 inhibitors against PM from GC has not been clearly determined. We established a highly metastatic subclone of murine GC cells to the peritoneum, YTN16P, by in vivo selection and evaluated the effects of intravenous (IV) or intraperitoneal (IP) administration of anti-PD-1 antibody on PM in immunocompetent mice model. Phenotypes of immune cells in the spleen and peritoneal metastatic lesions were determined with flow cytometry and immunohistochemistry. IP inoculation of YTN16P (1×106) resulted in multiple mesenteric metastases after 3 weeks. IV and IP administration of anti-PD-1mAb reduced the number of metastases to the mesentery by 30~40% compared with isotype controls. However, no differences were observed depending on the route of administration. Although splenocyte phenotypes were not altered, the densities of CD8(+) T cells in peritoneal tumors were significantly increased, whereas those of Gr-1(+) myeloid derived suppressor cells (MDSC) were significantly reduced in mice treated with anti-PD-1 mAb. PD-1 blockade therapy remodels the cellular immune composition of peritoneal tumors, which can partially suppress the PM from GC regardless of the route of administration. Adding anti-PD-1 antibody to chemotherapeutic regimens may enhance their anti-tumor effects against PM, which can lead to the prolongation of survival of patients with GC with peritoneal involvement.

High CD8/CD33 ratio in peritoneal metastatic lesions is associated with favorable prognosis in gastric cancer.

BackgroundTumor‐infiltrating lymphocytes (TILs) and other immune cells have been reported as a prognostic factor in several tumors, including gastric cancer, and they play an important role in antitumor effect at the primary site. There were few reports on the immune status in peritoneal metastatic lesions for gastric cancer.AimsThe aims of this study were to assess the prognostic significance of TILs (CD4, CD8, CD19, regulatory T cells [Tregs]), and myeloid‐derived suppressor cells (MDSCs) in peritoneal metastatic lesions.MethodsWe retrospectively investigated 60 patients for gastric cancer with peritoneal metastasis who were treated between 2009 and 2016 in our institute. Immunohistochemistry for CD4, CD8, CD19, FOXP3, and CD33 was performed in the peritoneal metastatic lesions. The absolute numbers of immune cells and ratios were evaluated, and the relationship between immune‐related marker and overall survival (OS) was investigated.ResultsA high infiltration of CD8+ lymphocytes or high CD8/CD33 ratio was a better prognosis for OS in univariate analysis using all immunologic variables (P = .012, P = .001). In multivariate analysis for clinical and immunologic variables, high CD8/CD33 ratio was identified as an independent prognostic factor for OS (Hazard ratio: 0.291, 95% confidence interval: 0.126‐0.670, P = .004).ConclusionHigh CD8/CD33 ratio and high infiltration of CD8+ lymphocytes in peritoneal metastatic lesions were favorable prognoses for gastric cancer patients with peritoneal metastasis. It is necessary to modify the immune microenvironment result to increase the level of CD8+ lymphocytes in the peritoneal metastatic lesions.

Extracellular vesicle derived miR-544 downregulates expression of tumor suppressor promyelocytic leukemia zinc finger resulting in increased peritoneal metastasis in gastric cancer.

Peritoneal metastasis (PM) is the main cause of poor prognosis in patients with advanced gastric cancer (GC). Increasing evidence has suggested that cancer-associated EVs in body fluids may assist in the diagnosis and treatment of GC. Here, we investigated the role of GC-derived EVs in PM development. Our results demonstrate that expression of the tumor suppressor promyelocytic leukemia zinc finger (PLZF) is decreased in GC tissues and PM lesions from GC patients. PLZF suppression promoted migration and invasion of peritoneal mesothelial HMrSV5 cells, while PLZF overexpression suppressed HMrSV5 cell migration and invasion. Microarray analysis revealed significantly upregulated expression of several miRNAs in EVs isolated from GC patients with PM, including miR-544. The increased miR-544 expression was confirmed in GC tissues and PM-derived EVs. Transfection with miR-544 reduced PLZF expression in HMrSV5 cells, while miR-544 inhibition increased PLZF expression. Incubation of GC cells with peritoneal mesothelial HMrSV5 cells showed that miR-544 could be transferred from GC-derived EVs to peritoneal cells, where it suppressed the PLZF expression. These findings indicate that EV-mediated transfer of miR-544 decreases the PLZF expression in PM lesions, which suggests miR-544 could potentially serve as a diagnostic biomarker and therapeutic target for treatment of GC patients.

Extravasated platelet aggregation contributes to tumor progression via the accumulation of myeloid-derived suppressor cells in gastric cancer with peritoneal metastasis.

Extravasated platelet aggregation (EPA) serves an important role in the cancer microenvironment during cancer progression, and has been demonstrated to interact with tumor cells in several types of cancer. EPA induces epithelial-mesenchymal transition (EMT) via transforming growth factor-β, and also recruits immunosuppressive cells, including regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSCs). However, the role of EPA in gastric cancer with peritoneal metastasis remains unknown. The present study analyzed the association between EPA and prognosis in patients with gastric cancer with peritoneal metastasis. The present study evaluated 62 patients diagnosed with advanced gastric cancer with peritoneal metastasis between 2001 and 2016. EPA, EMT, Treg cells and MDSCs in peritoneal metastatic lesions were detected by immunohistochemical evaluation of CD42b, SNAIL, FOXP3 and CD33, respectively. CD42b expression was observed in 56.5% (35/62) of peritoneal metastatic lesions. CD42b expression in peritoneal metastatic lesions was associated with poor overall survival compared with lower frequencies (hazard ratio, 2.03; 95% confidence interval, 1.12–3.69; P=0.018). SNAIL, FOXP3 and CD33 expression were not associated with overall survival, but CD33 expression was markedly higher in CD42b-positive patients (P=0.022). These results indicated that EPA affects immunosuppression by recruiting MDSCs in the tumor microenvironment via the secretion of soluble factors, resulting in tumor progression. EPA may be a novel therapeutic target for gastric cancer with peritoneal metastasis.

18F-FDG PET/CT in Staging Pediatric Rhabdomyosarcoma; Added benefits in comparison to conventional imaging.

Purpose: The aim was to evaluate the added value of 18F-FDG PET/CT in initial staging of pediatric Rhabdomyosarcoma patients in comparison to other conventional images. Materials and methods: This is a retrospective study including total 112 patients with pathologically proven RMS (52 female, 60 males; mean age, 5.8 years, with predominant embryonal type), Results of PET/CT were compared with computed tomography and/or MRI. Max SUV of the primary lesion, lymph nodes and distant metastases were evaluated in an individual and lesion analysis. Clinical follow-up (mean 27 months), and histo-pathological data were served as the standard of reference. Results: Among 112 patients, 45 (40%) patients proved metastatic byPET/CT, and 5 was Indeterminate. For primary tumor site, both diagnostic CT and FDG PET/CT show comparable results. Extremities were the most common primary site in metastatic patients & Alveolar type was more prevalent pathology among metastatic patients. Initial PET/CT upstages 13 patients (11.6%). Additional 50 lesions were determinate by PET/CT (21 nodal, 16 osseous, 3 peritoneal, 5 soft tissue nodules, 5 bone marrow involvement).Unusual site of metastases were detected by both modalities, includes suprarenal, spermatic cord and IVC thrombosis in individual patients .The sensitivity and PPV for PET/CT were higher than CT for nodal, osseous, soft tissue & peritoneal metastases.Conclusion: The current study showed that 18FDG-PET/CT is useful in initial staging of RMS patients as compared to CTregarding nodal, bone, bone marrow, soft tissue and peritoneal metastatic lesions, except for pulmonary deposits.

Macrophages on the Peritoneum are involved in Gastric Cancer Peritoneal Metastasis.

Tumor-associated macrophages (TAM) have been shown to support tumor growth and progression by various mechanisms. However, the roles of TAM in gastric cancer (GC) peritoneal metastasis remain elusive. To explore the roles of macrophages in the process of GC peritoneal metastasis, we performed the present study. Samples from the primary GC tumor beds, surgical margins, peritoneal metastatic lesions and surrounding tissue, and the Pouch of Douglas, were collected, fixed by formalin, and embedded with paraffin. Immunohistochemistry staining for macrophages markers was performed. The peritoneal lavage was obtained from a fraction of patients to analyze the ratios of epidermal growth factor (EGF)- and vascular endothelial growth factor (VEGF)-secreting macrophages in the peritoneal cavity. GC patients with peritoneal metastasis had increased levels of macrophages and alternatively activated macrophages in the peritoneum compared to those without dissemination. Patients bearing more macrophages in the peritoneum had a poorer prognosis. GC patients bearing peritoneal metastasis harbored an increased level of angiogenesis. Macrophages in the peritoneal cavity were a source of EGF and VEGF.Macrophages in the peritoneum of GC patients play a supportive role for peritoneal metastasis by producing EGF and VEGF. Macrophages in the peritoneum might be a therapeutic target in the future.

Indocyanine green fluorescence-navigated laparoscopic metastasectomy for peritoneal metastasis of hepatocellular carcinoma: a case report

BackgroundIndocyanine green (ICG) can selectively accumulate in primary hepatocellular carcinoma (HCC) and its extrahepatic metastases. ICG fluorescence imaging is an extremely sensitive intraoperative tool for detecting HCC foci and can be used to detect impalpable tumors in laparoscopic surgery. Here, we report a case of a 75-year-old man who underwent peritoneal metastasis resection of HCC using a laparoscopic near-infrared imaging system and ICG fluorescence-navigated surgery.Case presentationA 75-year-old man was referred to our department for peritoneal metastasis resection of HCC. Two years before admission, he had undergone transarterial embolization and segmentectomy of segment 6 with open surgery for ruptured HCC. Computed tomography revealed a 12-mm peritoneal metastatic lesion on the abdominal wall near the cut surface of the liver. No other metastases were observed; resection of the solitary metastasis was scheduled. ICG (0.5 mg/kg body weight) was intravenously injected, 72 h preoperatively. An endoscopic, ICG near-infrared fluorescence imaging system revealed clear green fluorescence, indicating peritoneal metastasis of HCC on the abdominal wall. The tumor was resected with adequate surgical margin by partially resecting the liver and diaphragm, followed by histological confirmation as peritoneal metastasis of HCC. No recurrence was observed after 12 months of follow-up.ConclusionsICG fluorescence can be useful in laparoscopic surgery for identifying peritoneal metastasis.

5-Aminolevulinic-acid-mediated Photodynamic Diagnosis Enhances the Detection of Peritoneal Metastases in Biliary Tract Cancer in Mice.

Previous studies on the accuracy of 5-aminolevulinic-acid-mediated photodynamic diagnosis (5-ALA PDD) have been reported for various cancers and brain surgery. However, biliary tract cancer is rare. Therefore, 5-ALA PDD has not been fully evaluated in biliary tract cancers. Small biliary tract cancer lesions such as peritoneal dissemination, liver metastases, and lymph node metastases are negative prognosticators in patients with biliary cancer. The purpose of this exploratory study was to determine if 5-ALA PDD could detect small biliary tract cancer lesions in murine models of biliary cancers. Biliary cancer cell lines (TFK-1, HuCCT-1, G415, HuH28, SSP25, RBE, KKU055 and KKU100) and Normal human dermal fibroblast cells were used to evaluate protoporphyrin IX (PpIX) accumulation in vitro. Subcutaneous tumor mice were established using two cell lines (TFK-1 and HuCCT-1). 5-ALA (250 mg/kg) was administered intraperitoneally, and fluorescent 5ALA-PDD was performed 3 h later to evaluate tumoral PpIX accumulation. A murine peritoneal disseminated nodule model was established by intraperitoneal injection of TFK-1 cells. Four weeks later, 5-ALA was administered intraperitoneally, and 5-ALA-PDD was performed 3 h post administration to evaluate PpIX accumulation in the disseminated nodules. The presence of tumor cells in tumors and nodules was confirmed by haematoxylin and eosin staining. Compared TO non-cancerous cell lines, PpIX accumulation was increased in biliary tract cancer cell lines. PpIX accumulation led to a strong fluorescent signal in all subcutaneous tumors. In the murine model of peritoneal dissemination, microdisseminated nodules (<1 mm) that could not be detected under white light were clearly visible using 5-ALA-PDD. 5-ALA PDD was useful for diagnosis of biliary tract cancer and detection of small peritoneal metastatic lesions in murine models of biliary cancers. Clinical studies and applications of 5-ALA PDD for biliary tract cancer are expected in the future.

Prognostic importance of peritoneal lesion-to-primary tumour standardized uptake value ratio in advanced serous epithelial ovarian cancer.

Using preoperative PET/CT, we evaluated the prognostic value of preoperative [18F]FDG uptake ratio between various metastatic lesions and primary tumour in patients with advanced serous epithelial ovarian cancer (EOC). We retrospectively reviewed patients with International Federation of Gynecology and Obstetrics (FIGO) stage III, IV serous EOC who underwent preoperative [18F]FDG PET/CT scans. Clinico-pathological variables and PET/CT parameters such as maximum standardized uptake value of the ovarian cancer (SUVovary), pelvic or para-aortic LN (SUVLN), peritoneal (SUVperit) and distant extra-peritoneal (SUVdist) metastatic lesions, and the metastatic lesion-to-ovarian cancer standardized uptake value ratio were assessed. Clinico-pathological data were retrospectively reviewed for 97 eligible patients. The median progression-free survival (PFS) was 18 months (range, 6-90 months) and 59 (60.8 %) patients experienced recurrence. In multivariate regression analysis, older age (p = 0.035, hazard ratio (HR) 1.032, 95 % CI 1.002-1.062), and high SUVperit/SUVovary (p = 0.046, HR 1.755, 95 % CI 1.011-3.047) were independent risk factors of recurrence. Patient group categorized by SUVperit/SUVovary showed significant difference in PFS (Log-Rank test, p = 0.001). In patients with advanced serous EOC, preoperative SUVperit/SUVovary measured by [18F]FDG PET/CT provides significant incremental performance for prediction of recurrence. • PET/CT data from advanced serous epithelial ovarian cancer patients were analysed. • Prognostic value of SUV ratio between metastatic and primary tumour was investigated. • SUV perit /SUV ovary provides incremental performance for prediction of recurrence.

Non-thermal plasma-treated solution demonstrates antitumor activity against pancreatic cancer cells in vitro and in vivo

Pancreatic cancer is associated with a high mortality rate. In advanced stage, patients often experience peritoneal carcinomatosis. Using a syngeneic murine pancreatic cancer cell tumor model, the effect of non-thermal plasma (NTP) on peritoneal metastatic lesions was studied. NTP generates reactive species of several kinds which have been proven to be of relevance in cancer. In vitro, exposure to both plasma and plasma-treated solution significantly decreased cell viability and proliferation of 6606PDA cancer cells, whereas mouse fibroblasts were less affected. Repeated intraperitoneal treatment of NTP-conditioned medium decreased tumor growth in vivo as determined by magnetic resonance imaging, leading to reduced tumor mass and improved median survival (61 vs 52 days; p < 0.024). Tumor nodes treated by NTP-conditioned medium demonstrated large areas of apoptosis with strongly inhibited cell proliferation. Contemporaneously, no systemic effects were found. Apoptosis was neither present in the liver nor in the gut. Also, the concentration of different cytokines in splenocytes or blood plasma as well as the distribution of various hematological parameters remained unchanged following treatment with NTP-conditioned medium. These results suggest an anticancer role of NTP-treated solutions with little to no systemic side effects being present, making NTP-treated solutions a potential complementary therapeutic option for advanced tumors.