Peritoneal Tumor Research Articles

Ras/MAPK signalling intensity defines subclonal fitness in a mouse model of hepatocellular carcinoma.

Quantitative differences in signal transduction are to date an understudied feature of tumour heterogeneity. The MAPK Erk pathway, which is activated in a large proportion of human tumours, is a prototypic example of distinct cell fates being driven by signal intensity. We have used primary hepatocyte precursors transformed with different dosages of an oncogenic form of Ras to model subclonal variations in MAPK signalling. Orthotopic allografts of Ras-transformed cells in immunocompromised mice gave rise to fast-growing aggressive tumours, both at the primary location and in the peritoneal cavity. Fluorescent labelling of cells expressing different oncogene levels, and consequently varying levels of MAPK Erk activation, highlighted the selection processes operating at the two sites of tumour growth. Indeed, significantly higher Ras expression was observed in primary as compared to secondary, metastatic sites, despite the apparent evolutionary trade-off of increased apoptotic death in the liver that correlated with high Ras dosage. Analysis of the immune tumour microenvironment at the two locations suggests that fast peritoneal tumour growth in the immunocompromised setting is abrogated in immunocompetent animals due to efficient antigen presentation by peritoneal dendritic cells. Furthermore, our data indicate that, in contrast to the metastatic-like outgrowth, strong MAPK signalling is required in the primary liver tumours to resist elimination by NK (natural killer) cells. Overall, this study describes a quantitative aspect of tumour heterogeneity and points to a potential vulnerability of a subtype of hepatocellular carcinoma as a function of MAPK Erk signalling intensity.

Intraperitoneal administration of cabazitaxel-loaded nanoparticles in peritoneal metastasis models

Colorectal and ovarian cancers frequently develop peritoneal metastases with few treatment options. Intraperitoneal chemotherapy has shown promising therapeutic effects, but is limited by rapid drug clearance and systemic toxicity. We therefore encapsulated the cabazitaxel taxane in poly(alkyl cyanoacrylate) (PACA) nanoparticles (NPs), designed to improve intraperitoneal delivery. Toxicity of free and encapsulated cabazitaxel was investigated in rats by monitoring clinical signs, organ weight and blood hematological and biochemical parameters. Pharmacokinetics, biodistribution and treatment response were evaluated in mice. Biodistribution was investigated by measuring both cabazitaxel and the 2-ethylbutanol NP degradation product. Drug encapsulation was shown to increase intraperitoneal drug retention, leading to prolonged intraperitoneal drug residence time and higher drug concentrations in peritoneal tumors. As a result, encapsulation of cabazitaxel improved the treatment response in two in vivo models bearing intraperitoneal tumors. Together, these observations indicate a strong therapeutic potential of NP-based cabazitaxel encapsulation as a novel treatment for peritoneal metastases.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignant tumors in children: Initial experience in a single institution.

Peritoneal malignant tumors in children are rare but commonly associated with disease progression and poor outcome. The successful treatment experience of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in adult peritoneal carcinoma has been applied to pediatric peritoneal malignancy in recent years. However, patients with desmoplastic small round cell tumor (DSRCT) accounted for the majority of patients treated with CRS and HIPEC in previous studies. The role of CRS and HIPEC remains controversial due to the rarity of the disease and the limited sample size of studies. Additionally, the cases using CRS and HIPEC except DSRCT were mainly small case reports with unclear outcomes. We present our experience in the treatment of pediatric peritoneal malignancies using CRS and HIPEC, with more emphasis on the safety, feasibility, and short-term outcome. A retrospective query from December 2019 to February 2022 identified 19 children with peritoneal malignancies who underwent CRS and HIPEC in our institution. Clinical characteristics, therapies, and outcomes were summarized and analyzed. The median age of the patients was 6.4 years (range, 0.7-13.9 years). The histologic types included rhabdomyosarcoma (7), Wilms tumor (2), clear cell sarcoma of the kidney (2), undifferentiated sarcoma (2), immature teratoma (1), peritoneal serous carcinoma (1), malignant rhabdoid of the kidney (1), malignant germ cell tumor (1), neuroblastoma (1), and epithelioid inflammatory myofibroblast sarcoma (1). Seven patients underwent initial operation, and 12 patients received reoperation for tumor recurrence. The median peritoneal carcinomatosis index was 5 (range, 2-21). There were no perioperative deaths or life-threatening complications of CRS and HIPEC. Two patients had grade 3 complications of wound infection and wound dehiscence. With a median follow-up time of 14 months (range, 1.5-31 months), 14 patients were alive, and 5 died of tumor recurrence. Of the 14 patients who were alive, 2 relapsed after CRS and HIPEC and then received radiotherapy and molecular-targeted therapy or chemotherapy. CRS and HIPEC are safe and feasible in children, without increasing serious complications in the peri- and postoperative periods. The complication is acceptable. The short-term outcome shows possible effectiveness in pediatric peritoneal malignant tumors. The long-term effectiveness needs to be verified by additional cases and long-term follow-ups.

18F-FDG PET/CT in peritoneal tumors: a pictorial review

18F-FDG PET/CT in peritoneal tumors: a pictorial review

A small intestine neuroendocrine tumor: case report

Small intestinal neuroendocrine tumors (SI-NETs) are the most common small bowel tumors, they are recognized for their ability to produce hormones causing mesenteric fibrosis and carcinoid syndrome. They tend to have better surgical rate than adenocarcinomas.this work was made as an update on one of the most aggressive small intestine tumors. Presentation of case We discuss here the case of a sixth years old female woman admitted and operated for a small intestine neuroendocrine tumor with peritoneal carcinosis Discussion Neuroendocrine tumors are secreting tumors, locating mainly in the small intestine with a high malignancy risk. At the time of the diagnosis, lymph node, liver metastasis and peritoneal carcinosis are very common. Patients may be asymptomatic or consult for abdominal pain, rarely bowel obstruction, diagnosis is radiologically made and confirmed indeed histologically. Treatment involves surgery, chemotherapy, immunotherapy and radiotherapy and surveillance is assured by biomarkers, endoscopy and Octreoscan when metastatic. Conclusion The SI-NETs are rare but their incidence and prevalence have been increasing. Histologically, diagnosis is confirmed by positive immunohistochemical staining. Treatment and prognosis depend on the grade and stage of the tumor. Immunotherapy will serve as a future treatment modality.

Atypically Gastric Tumor with Unexpected Evolution: A Case Report

We present the case of a 62 year old male with no relevant medical history, who for the last two months had been complaining of dysphagia for solids and liquids, marked physical fatigue, oliguria. Clinical examination revealed palor and dehydrated skin, as well as a tumoral mass of 10/10 cm palpable in the upper abdomen. Upper digestive endoscopy was performed, showing a vegetant lesion of 6 cm on the gastric angle, with a central ulcer of 4 cm. The oesophagus and duodenum were normal, and Helicobacter pylori test was negative. Histological exam from the gastric lesion revealed diffuse large-cell malignant lymphoid tumoral proliferation, with tumoral cells infiltrating the mucosa between the glands. Immunohistochemical analysis diagnosed B cell lymphoma. CT scan of the thorax, abdomen and pelvis was performed, revealing multiple tumors involving the gastric walls, the posterior parietal peritoneum, the intra-peritoneal fat, the pancreatic tissues and the right antero-inferior mediastinum, as well as multiple adenopathies on both sides of the diaphragm and ascites. We performed paracentesis, and malignant cells were detected in the peritoneal fluid. Bone marrow biopsy was normal. The patient was referred to the hematology department for treatment. He received chemotherapy including CHOP followed by RICE with the disappearance of the gastric tumor on upper endoscopy and the disappearance of peritoneal, mediastinal and pancreatic region tumors with the persistence of a circumferential thickening of the horizontal gastric region walls on CT reevaluation.

Patterns and Timing of Recurrence following CRS and HIPEC in Colorectal Cancer Peritoneal Metastasis.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC) is an established treatment of Colorectal Peritoneal Metastases (CRPM). This study aims to determine the timing and patterns of recurrent disease on imaging following complete CRS/HIPEC. Retrospective analysis of a national peritoneal tumour service database identified CRPM patients with complete CRS/HIPEC(CC0) from 2005 to-2018. Patients with<2 years follow-up or and those where post-operative histology from the CRS/HIPEC procedure did not confirm CRPM from their original colorectal cancer were excluded. Time to recurrence was measured from surgery to first radiologically illustrated recurrence. CT was the primary modality used, supplemented by PET-CT or MRI if required. Outcomes of interest were survival data (including overall survival (OS), disease-free survival (DFS) and peritoneal-recurrence free survival (PRFS)), timing and patterns of recurrent disease. 146 of the 176 patients identified were eligible for inclusion. Median OS for all study patients was 45.2 months (95% CI 38-53 months), median DFS was 11.7 months (95% CI 9-14 months), and median PRFS was 25.2 months (95% CI 14.7-30 months). Recurrent disease was seen in 112 cases (77%), radiologically classified as intraperitoneal in 50 patients (44%), single site systemic in 21 patients (19%) and multi-site in 41 patients (37%). CT detection rate for disease recurrence was 88%. Subgroup analyses showed that PCI ≥12, positive nodal primary disease and synchronous peritoneal disease were associated with worse outcomes. Patients selected for CRS/HIPEC for CRPM have an OS>45 months, with the majority recurring systemically within a year. Peritoneal recurrence is a later event after several years. Surveillance programs in this group should be most intensive in the first 2 years after surgery, using CT with oral and intravenous contrast.

Immune Profile of Blood, Tissue and Peritoneal Fluid: A Comparative Study in High Grade Serous Epithelial Ovarian Cancer Patients at Interval Debulking Surgery.

High-grade serous epithelial ovarian carcinoma (HGSOC) is an immunogenic tumor with a unique tumor microenvironment (TME) that extends to the peritoneal cavity. The immunosuppressive nature of TME imposes the major challenge to develop effective treatment options for HGSOC. Interaction of immune cells in TME is an important factor. Hence, a better understanding of immune profile of TME may be required for exploring alternative treatment options. Immune profiling of peritoneal fluid (PF), tumor specimens, and blood were carried out using flowcytometry, ELISA, and Procartaplex immunoassay. The frequency of CD56BrightNK cells and expression of functional receptors were reduced in PF. Increased activating NKp46+CD56DimNK cells may indicate differential antitumor response in PF. Functional receptors on NK, NKT-like and T cells were reduced more drastically in tumor specimens. Soluble ligands MIC-B and PVR were reduced, whereas B7-H6 was increased in PF. Dissemination of tumor cells contributes to soluble ligands in PF. A differential cytokine profile was found in serum and PF as IL-2, IL-8, IL-15, IL-27, IFN-γ, and GM-CSF were elevated specifically in PF. In conclusion, the differential immune profile and correlation of soluble parameters and NK cell receptors with chemo response score may add knowledge to understand anti-tumor immune response to develop effective treatment modality.

Molecular Classification of Appendiceal Adenocarcinoma.

Appendiceal adenocarcinomas (ACs) are rare, histologically diverse malignancies treated as colorectal cancers despite having distinct biology and clinical behavior. To guide clinical decision making, we defined molecular subtypes of AC associated with patient survival, metastatic burden, and chemotherapy response. A comprehensive molecular analysis was performed in patients with AC to define molecular subtypes. Associations between molecular subtype and overall survival, intraoperative peritoneal cancer index, and first-line chemotherapy response were assessed adjusting for histopathologic and clinical variables using multivariable Cox proportional hazards, linear regression, and logistic regression models. We defined distinct molecular lineages of mucinous appendiceal adenocarcinoma (MAAP) from co-occurring mutations in GNAS, RAS, and TP53. Of 164 MAAP tumors, 24 were RAS-mutant (mut) predominant (RAS-mut/GNAS-wild-type [wt]/TP53-wt) with significantly decreased mutations and chromosomal alterations compared with tumors with GNAS mutations (GNAS-mut predominant) or TP53 mutations (TP53-mut predominant). No patient with RAS-mut predominant subtype metastatic MAAP died of cancer, and overall survival in this subgroup was significantly improved compared with patients with GNAS-mut (P = .05) and TP53-mut (P = .004) predominant subtypes. TP53-mut predominant subtypes were highly aneuploid; increased tumor aneuploidy was independently (P = .001) associated with poor prognosis. The findings retained significance in patients with any metastatic AC. RAS-mut predominant metastases exhibited reduced peritoneal tumor bulk (P = .04) and stromal invasion (P < .001) compared with GNAS-mut or TP53-mut predominant tumors, respectively. Patients with RAS-mut predominant MAAP responded more to first-line chemotherapy (50%) compared with patients with GNAS-mut predominant tumors (6%, P = .03). AC molecular patterns identify distinct molecular subtypes: a clinically indolent RAS-mut/GNAS-wt/TP53-wt subtype; a chemotherapy-resistant GNAS-mut predominant subtype; and an aggressive, highly aneuploid TP53-mut predominant subtype. Each subtype exhibits conserved clinical behavior irrespective of histopathology.

Acute epiploic appendagitis - a rare differential diagnosis of acute abdomen.

Acute epiploic appendagitis is a rare differential diagnosis of unclear or acute abdomen. To describe - by means of a scientific case report - the extraordinary diagnosis of acute epiploic appendagitis along with contained diverticulitis and incarcerated herniation of the greater omentum into the hernial sac of a former trocar site (medical history, significant for laparoscopic ovarian cyst removal) in a 29-year-old female based on experiences obtained in the successful clinical case management, and on selective references from medical scientific literature. Medical history: A 29-year-old female was admitted with abdominal pain in the lower left quadrant. She reported a laparoscopic ovarian cyst removal 3 years prior. Physical examination of the abdomen revealed tenderness in the lower left quadrant without a palpable mass.Leading diagnoses were found using transabdominal ultrasound and confirmed by an abdominal CT scan; namely, incarcerated trocar hernia, diverticulitis of sigmoid colon, and acute epiploic appendagitis. Therapeutic approach was comprised of an explorative laparoscopy (because of the incarcerated hernia), adhesiolysis, removal of a tip of the greater omentum out of the hernial sac, closure of the hernial orifice, and removal of an unclear, inflamed, and bloody fatty tissue from the wall of the descending colon (histopathological investigation confirmed acute epiploic appendagitis). This was flanked by conservative treatment of diverticulitis of the sigmoid colon.Further clinical course was uneventful, with discharge on the 3rd postoperative day with favorable long-term outcome, characterized by no further complaints for 15 months. Acute epiploic appendagitis is an inflammatory, usually self-limiting condition of the epiploic appendages of the colon. It typically manifests with abdominal pain in the lower left quadrant. Imaging is an important diagnostic tool to determine whether the patient has, in fact, acute epiploic appendagitis, so recognizing the characteristic oval lesions with the surrounding inflammation and central fat attenuation on CT, as well as the hyperechoic oval lesions with a hypoechoic peripheral band on ultrasound images is crucial. Nevertheless, it is often overlooked in patients and confused with other differential diagnoses, such as appendicitis or diverticulitis. Although the condition appears infrequently, it is essential to be proficient in the diagnostic evaluation, as a misdiagnosis may lead to unnecessary treatment and even surgical intervention. , the patient was initially diagnosed with an incarcerated abdominal hernia, and therefore subsequently underwent surgery. The inflamed epiploic appendage was discovered in laparoscopic exploration, removed, and confirmed through the histopathology report. This is an approach to be performed with great caution so as not to 1. : misinterpret an inflamed diverticula or covered perforation of it as well as not 2. : overlooking a peritoneal tumor lesion.

Agent-based modeling predicts RAC1 is critical for ovarian cancer metastasis.

Experimental and computational studies pinpoint rate-limiting step(s) in metastasis governed by Rac1. Using ovarian cancer cell and animal models, Rac1 expression was manipulated, and quantitative measurements of cell-cell and cell-substrate adhesion, cell invasion, mesothelial clearance, and peritoneal tumor growth discriminated the tumor behaviors most highly influenced by Rac1. The experimental data were used to parameterize an agent-based computational model simulating peritoneal niche colonization, intravasation, and hematogenous metastasis to distant organs. Increased ovarian cancer cell survival afforded by the more rapid adhesion and intravasation upon Rac1 overexpression is predicted to increase the numbers of and the rates at which tumor cells are disseminated to distant sites. Surprisingly, crowding of cancer cells along the blood vessel was found to decrease the numbers of cells reaching a distant niche irrespective of Rac1 overexpression or knockdown, suggesting that sites for tumor cell intravasation are rate limiting and become accessible if cells intravasate rapidly or are displaced due to diminished viability. Modeling predictions were confirmed through animal studies of Rac1-dependent metastasis to the lung. Collectively, the experimental and modeling approaches identify cell adhesion, rapid intravasation, and survival in the blood as parameters in the ovarian metastatic cascade that are most critically dependent on Rac1.

Evaluation of direct intramural injection to the bladder wall as a method for developing orthotopic tumor models.

Bladder cancer poses a great burden on society and its high rate of recurrence and treatment failure necessitates use of appropriate animal models to study its pathogenesis and test novel treatments. Orthotopic models are superior to other types since they provide a normal microenvironment. Four methods are described for developing bladder cancer models inside the animal's bladder. Direct intramural injection is one of these methods and is widely used. However, its efficacy in model development has not yet been studied. We aimed to evaluate the efficacy and success rate of the direct intramural injection method of developing an orthotopic model for the study of bladder cancer. Tumor cell lines were prepared in four microtubes. Aliquots of 200 × 103 cells were injected through a 27 gauge needle into the ventral wall of the bladders of 4 male and 4 female BALB/c mice following a midline 1cm laparotomy incision. In addition, 1 million cells from each microtube were injected into the flanks of control mice. To prevent infection and alleviate pain, 5mg/kg enrofloxacin and 2.5mg/kg flunixin meglumine, respectively, were injected subcutaneously. Tumors formed in all mice, resulting in 100% take rate and zero post-operation mortality. Surgery time was ≤15 min per mouse. In two mice, tumors were found in the peritoneal space as well. Direct intramural injection is a rapid, reliable, and reproducible method for developing orthotopic models of bladder cancer. It can be done on both male and female mice and only requires readily available surgical tools. However, needle track can result in cell spillage and peritoneal tumors.

A PD-L1-targeting chimeric switch receptor enhances efficacy of CAR-T cell for pleural and peritoneal metastasis

Pleural and peritoneal metastasis accompanied by malignant pleural effusion (MPE) or malignant ascites (MA) is frequent in patients with advanced solid tumors that originate from the lung, breast, gastrointestinal tract and ovary. Regional delivery of CAR-T cells represents a new strategy to control tumor dissemination in serous cavities. However, malignant effusions constitute an immune-suppressive environment that potentially induces CAR-T cell dysfunction. Here, we demonstrated that the anti-tumor cytotoxicity of conventional 2nd-generation CAR-T cells was significantly inhibited by both the cellular and non-cellular components of MPE/MA, which was primarily attributed to impaired CAR-T cell proliferation and cytokine production in MPE/MA environment. Interestingly, we found that PD-L1 was widely expressed on freshly-isolated MPE/MA cells. Based on this feature, a novel PD-L1-targeting chimeric switch receptor (PD-L1.BB CSR) was designed, which can bind to PD-L1, switching the inhibitory signal into an additional 4-1BB signal. When co-expressed with a 2nd-generation CAR, PD-L1.BB CSR-modified CAR-T cells displayed superior fitness and enhanced functions in both culture medium and MPE/MA environment, causing rapid and durable eradication of pleural and peritoneal metastatic tumors in xenograft models. Further investigations revealed elevated expressions of T-cell activation, proliferation, and cytotoxicity-related genes, and we confirmed that PD-L1 scFv and 4-1BB intracellular domain, the two important components of PD-L1.BB CSR, were both necessary for the functional improvements of CAR-T cells. Overall, our study shed light on the clinical application of PD-L1.BB CSR-modified dual-targeting CAR-T cells. Based on this study, a phase I clinical trial was initiated in patients with pleural or peritoneal metastasis (NCT04684459).

Effect of 5-Fluoro-Uracile + Oxaliplatin chemotherapy on the histological response of PEritoneal and hePatIc corectal metasTases in a mOuse model: PEPITO experimental study

BackgroundThe histological responses (HRs) after systemic chemotherapy should be used to determine the optimal management of patients with peritoneal and liver metastasis from colorectal cancer (cPM, cLM), in curative intent. We aimed to compare HRs of cPM and cLM in metastatic mice model after chemotherapy. MethodsColon carcinoma CT26-luc cells were transplanted into syngeneic BALB/c mice by intraperitoneal (leading to cPM), intrasplenic (leading to cLM), or intraperitoneal + intrasplenic (leading to cPM cLM) injections and follow up using bioluminescence during 21 days. Bi-chemotherapeutic treatment (5-fluorouracil at D11, D17, and D20, and oxaliplatin at D13 and D19) was administered. The peritoneal cancer index (PCI) and HRs using Peritoneal Regression Grading Score (PRGS) and Tumor Regression Grade (TRG) classifications were analyzed at day 21. ResultsUnlike bioluminescence rate, PCI was reduced after chemotherapy in all treated groups with cPM comparatively to controls (33 ± 9.5 vs. 19.8 ± 5, p = 0.002 for cPM groups; 37.7 ± 3.6 vs. 25.2 ± 10.8, p = 0.0003 for the cPM + cLM groups). The complete or major HR rates were higher in all treated groups compared to the non-treated mice (cPM, 2.29 ± 0.55 vs. 3.56 ± 1.01; cLM, 2.43 ± 1.89 vs. 4.86 ± 0.378; cPM + cLM, 2.73 ± 1.03 and 2.2 ± 0.65 vs. 3.79 ± 0.75 and 4.36 ± 0.43). The complete or major HR rates after chemotherapy were similar across the metastatic sites in 60% for cPM + cLM group. ConclusionsThe efficacy of chemotherapeutic treatment did not differ between the metastatic sites. Murine models are suitable in histological analyses to study tumor development and regression but clinical study will be performed to confirm these results.

RAS Mutation Status Should Not Be Used to Predict Outcome from Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases

BackgroundGenetic biomarkers guide systemic anti-cancer treatment (SACT) in metastatic colorectal cancer. It has been suggested they have a role in selecting patients with colorectal peritoneal metastases (CRPM) for cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). This study aims to quantify the effect of mutation status on overall survival (OS), adjusting for confounders such as pre-operative systemic anticancer treatment (SACT).Patients and MethodsRetrospective analysis of patients undergoing CRS/HIPEC for CRPM at a national peritoneal tumour centre (2004–2017) was performed. Demographics, treatment history and operative data were extracted. Known biomarker gene mutation status was noted including: KRAS, NRAS, BRAF, PIK3CA and MMR. Cox regression analysis and Kaplan–Meier curves were used to determine overall survival.ResultsOne hundred ninety-five patients were included. Median follow-up time was 34.7 months (range 5.4–184.9 months) and median OS was 38.7 months (95% CI 32.4–44.9 months). Biomarker status was as follows: KRAS (n = 114), NRAS (n = 85), BRAF (n = 44), PIK3CA (n = 15) and MMR (n = 21). Mutation rates were 45.6%, 3.5%, 13.6%, 13.3% and 14.3%, respectively. Seventy-four per cent underwent complete cytoreduction (CC = 0), 81% received SACT pre-CRS/HIPEC and 65% post-CRS/HIPEC. RAS (p = 0.21) or BRAF (p = 0.109) mutation status did not predict OS. Nodal involvement, extramural vascular invasion, Peritoneal Cancer Index (PCI) score, CC score, SACT post-HIPEC and NRAS mutation were significant negative predictors of OS in univariate analysis (p < 0.05). Multivariate Cox regression confirmed CC-score > 1 (HR: 7.599, 95% CI 3.402–16.974, p < 0.0001) as a negative predictor of OS. RAS mutation status did not affect outcome (HR: 1.682, 95% CI 0.995–2.843, p = 0.052).ConclusionsRAS mutation status should not in isolation be used to select patients for CRS/HIPEC.

Peritoneal Tumors of Mullerian Origin: A Case Report and Review of the Literature

Primary peritoneal tumors share a common anatomical site and therefore their clinical manifestations are very similar. When peritoneal masses are detected, the tentative initial diagnosis is secondary to metastatic disease, which has been determined most frequently in the peritoneal cavity. However, primary peritoneal tumors should always be included in the differential diagnosis. Among the primary malignant peritoneal neoplasms, mesothelial tumors have been identified (malignant mesothelioma, well-differentiated papillary mesothelioma, benign cystic mesothelioma, adenomatoid tumor of the peritoneum), epithelial-type tumors (primary peritoneal serous carcinoma, primary peritoneal serous borderline tumor), tumors of the smooth muscle (disseminated peritoneal leiomyomatosis) and tumors of uncertain or undetermined origin (desmoplastic small round cell tumor, peritoneal solitary fibrous tumor).

Peritoneal Tumors of Mullerian Origin: A Case Report and Review of the Literature

Peritoneal Tumors of Mullerian Origin: A Case Report and Review of the Literature

Malignant Peritoneal Mesothelioma Features Shown by FDG-PET/CT.

Malignant peritoneal meso-thelioma (MPeM) has no specific imaging findings that can distinguish it from other peritoneal tumors and the accuracy of peritoneal cytology is low, therefore definitive diagnosis is usually performed by histology. This study investigated whether 18 F-fluorodeoxyglucose positron emission tomography/ computed tomography representing glucose metabolism is a useful modality for identifying biopsy sites using the tumor viability of MPeM. Sixty MPeM patients underwent pre-biopsy FDG-PET/CT examination. The findings were retrospectively evaluated, and histopathological subtype differences were investigated. The diffuse MPeM type was found in 45 (75.0%) and the localized type in 15 (25.0%) cases. The most frequent site of occurrence was the peritoneum (91.7%), followed by the omentum (51.7%). FDG-avid results were noted in 55 patients (91.7%), while 5 (8.3%) showed no FDG uptake with a variety of maximum standardize uptake value (SUVmax) values (range=0-16.77, mean=7.32±4.05). In the 53 epithelial cases, mean SUVmax (7.09±4.07, range=0-16.77) was slightly lower compared to the 4 biphasic (8.30±4.70, range=2.35-13.36) and 3 sarcomatoid (10.08±2.64, range=8.21-13.10) cases, without any significant difference (p=0.12). Diffuse and focal disease patterns showed similar percentages in the three types. Six cases (10.0%) had nodal metastases and 6 (10.0%) extra-abdominal metastases. Compared to the biphasic and sarcomatoid groups, nodal metastases were more common in the epithelial group, while extra-abdominal metastases were more often seen in the biphasic and sarcomatoid groups. Ascites was seen in 53 (83.3%), pleural effusion in 43 (71.7%), and pleural plaque in 31 (51.7%) cases. Through reviewing and elucidation of the FDG-PET/CT features of MPeM, it was shown that FDG-PET/CT is an extremely useful modality for identifying biopsy sites of MPeM.

Should Positive Cytology Revealed by Intraoperative Lavage Preclude Radical Resection in Resectable Pancreatic Cancer?: A Systemic Review and Meta-analysis.

The aims of this review were to determine whether positive peritoneal lavage cytology (CY+) precludes radical resection in pancreatic cancer and to propose prospections for future studies. MEDLINE, Embase, and Cochrane Central were searched for related articles. Dichotomous variables and survival outcomes were analyzed with the estimation of odds ratio and hazards ratio (HR), respectively. A total of 4905 patients were included, of which 7.8% were CY+. Positive peritoneal lavage cytology was correlated with poor overall survival (univariate survival analysis [HR, 2.35; P < 0.00001]; multivariate analysis [HR, 1.62; P < 0.00001]), poor recurrence-free survival (univariate survival analysis [HR, 2.50; P < 0.00001]; multivariate analysis [HR, 1.84; P < 0.00001]), and higher initial peritoneal recurrence rate (odds ratio, 5.49; P < 0.00001). Although CY+ predicts poor prognosis and a higher risk of peritoneal metastasis after curative resection, it is not sufficient to preclude curative resection based on the current evidence, and high-quality trials should be conducted to assess the prognostic impact of operation among resectable CY+ patients. In addition, more sensitive and accurate methods to detect peritoneal exfoliated tumor cells and more effective comprehensive treatment for resectable CY+ pancreatic cancer patients are clearly warranted.

Compound C Inhibits Ovarian Cancer Progression via PI3K-AKT-mTOR-NFκB Pathway.

Simple SummaryOvarian cancer is a deadly cancer due to its late diagnosis. Despite aggressive surgery and chemotherapy recurrence of a resistant aggressive disease is common. Thus, there is an unmet need to develop new therapeutics that target cancer cells and prevent recurrence and resistance. In the present study, we used multiple approaches to report and validate a novel therapeutic compound, compound C, that targets cancer cells and renders them more sensitive to standard of care therapy. Our study also reports novel mechanism of action of compound C and warrants its further development in the treatment of ovarian cancer patients.Epithelial Ovarian cancer (OvCa) is the leading cause of death from gynecologic malignancies in the United States, with most patients diagnosed at late stages. High-grade serous cancer (HGSC) is the most common and lethal subtype. Despite aggressive surgical debulking and chemotherapy, recurrence of chemo-resistant disease occurs in ~80% of patients. Thus, developing therapeutics that not only targets OvCa cell survival, but also target their interactions within their unique peritoneal tumor microenvironment (TME) is warranted. Herein, we report therapeutic efficacy of compound C (also known as dorsomorphin) with a novel mechanism of action in OvCa. We found that CC not only inhibited OvCa growth and invasiveness, but also blunted their reciprocal crosstalk with macrophages, and mesothelial cells. Mechanistic studies indicated that compound C exerts its effects on OvCa cells through inhibition of PI3K-AKT-NFκB pathways, whereas in macrophages and mesothelial cells, CC inhibited cancer-cell-induced canonical NFκB activation. We further validated the specificity of the PI3K-AKT-NFκB as targets of compound C by overexpression of constitutively active subunits as well as computational modeling. In addition, real-time monitoring of OvCa cellular bioenergetics revealed that compound C inhibits ATP production, mitochondrial respiration, and non-mitochondrial oxygen consumption. Importantly, compound C significantly decreased tumor burden of OvCa xenografts in nude mice and increased their sensitivity to cisplatin-treatment. Moreover, compound C re-sensitized patient-derived resistant cells to cisplatin. Together, our findings highlight compound C as a potent multi-faceted therapeutic in OvCa.