Integrating the Idylla™ System Alongside a Real-Time Polymerase Chain Reaction and Next-Generation Sequencing for Investigating Gene Fusions in Pleural Effusions from Non-Small-Cell Lung Cancer Patients: A Pilot Study.

Malignant pleural effusion (MPE) from patients with advanced non-small-cell lung cancer (NSCLC) has been proven valuable for molecular analysis; however, simultaneous detection of driver fusions in MPE is still challenging. In this study, we investigated the Idylla™ GeneFusion Panel, a stand-alone test in tissue samples, in the evaluation of ALK, ROS1, RET and MET ex14 skipping mutations in MPE and compared its performance with routine reference methods (Real-time-based and Next-generation Sequencing-NGS). The inclusion criteria for sample selection were as follows: advanced NSCLC harboring ALK, ROS1, RET fusions or MET exon-skipping alterations and the availability of MPE collected at diagnosis or disease progression. Molecular alterations have been investigated on tissue by fluorescence in situ hybridization (FISH) or Real-time PCR or NGS. For molecular profiling with the Idylla™ GeneFusion, 200 µL of MPE supernatants combined with 50 µL of RNA Later solution were loaded into the Idylla™ cartridge without cfRNA extraction. The Idylla™ GeneFusion Assay performed on MPEs was able to confirm molecular profile, previously diagnosed with conventional methods, in all cases. Our data confirm that MPE are suitable material for investigating fusion alterations. The Idylla™ GeneFusion, although indicated for investigation of tissue samples, offers the possibility of performing a molecular characterization of supernatants without undertaking the entire cfRNA extraction procedure providing a rapid and reliable strategy for the detection of actionable genetic alterations.

IL-10, IL-13, Eotaxin and IL-10/IL-6 ratio distinguish breast implant-associated anaplastic large-cell lymphoma from all types of benign late seromas.

Breast implant-associated anaplastic large-cell lymphoma (BI-ALCL) is an uncommon peripheral T cell lymphoma usually presenting as a delayed peri-implant effusion. Chronic inflammation elicited by the implant has been implicated in its pathogenesis. Infection or implant rupture may also be responsible for late seromas. Cytomorphological examination coupled with CD30 immunostaining and eventual T-cell clonality assessment are essential for BI-ALCL diagnosis. However, some benign effusions may also contain an oligo/monoclonal expansion of CD30 + cells that can make the diagnosis challenging. Since cytokines are key mediators of inflammation, we applied a multiplexed immuno-based assay to BI-ALCL seromas and to different types of reactive seromas to look for a potential diagnostic BI-ALCL-associated cytokine profile. We found that BI-ALCL is characterized by a Th2-type cytokine milieu associated with significant high levels of IL-10, IL-13 and Eotaxin which discriminate BI-ALCL from all types of reactive seroma. Moreover, we found a cutoff of IL10/IL-6 ratio of 0.104 is associated with specificity of 100% and sensitivity of 83% in recognizing BI-ALCL effusions. This study identifies promising biomarkers for initial screening of late seromas that can facilitate early diagnosis of BI-ALCL.

Human lung adenocarcinoma cell cultures derived from malignant pleural effusions as model system to predict patients chemosensitivity.

BACKGROUND: Lung cancer is the leading cause of cancer related deaths and Malignant Pleural Effusion (MPE) is a frequent complication. Current therapies suffer from lack of efficacy in a great percentage of cases, especially when cancer is diagnosed at a late stage. Moreover patients' responses vary and the outcome is unpredictable. Therefore, the identification of patients who will benefit most of chemotherapy treatment is important for accurate prognostication and better outcome. In this study, using malignant pleural effusions (MPE) from non-small cell lung cancer (NSCLC) patients, we established a collection of patient-derived Adenocarcinoma cultures which were characterized for their sensitivity to chemotherapeutic drugs used in the clinical practice. METHODS: Tumor cells present in MPEs of patients with NSCLC were isolated by density gradient centrifugation, placed in culture and genotyped by next generation sequencing. In a subset of cases patient derived xenografts (PDX) were obtained upon tumor cell inoculation in rag2/IL2 knock-out mice. Isolated primary cultures were characterized and tested for drug sensitivity by in vitro proliferation assays. Additivity, antagonism or synergy for combinatorial treatments were determined by analysis with the Calcusyn software. RESULTS: We have optimized isolation procedures and culture conditions to expand in vitro primary cultures from Malignant Pleural Effusions (MPEs) of patients affected by lung adenocarcinomas, the most frequent form of non small cell lung cancer. Using this approach we have been able to establish 16 primary cultures from MPEs. Cells were banked at low passages and were characterized for their mutational pattern by next generation sequencing for most common driver mutations in lung cancer. Moreover, amplified cultures were shown to engraft with high efficiency when injected in immunocompromised mice. Cancer cell sensitivity to drugs used in standard chemotherapy regimens was assessed either individually or in combination. Differential chemosensitivity and different mutation profiles were observed which suggests that this isolation method could provide a platform for predicting the efficacy of chemotherapy in the clinical setting. Most importantly for six patients it was possible to establish a correlation between drug response in vitro and response to therapy in the clinic. CONCLUSIONS: Results obtained using primary cultured cells from MPEs underscore the heterogeneity of NSCLC in advanced stage as indicated by drug response and mutation profile. Comparison of data obtained from in vitro assays with patients' responses to therapy leads to the conclusion that this strategy may provide a potentially useful approach for evaluating individual chemosensitivity profile and tailor the therapy accordingly. Furthermore, combining MPE-derived primary cultures with their genomic testing allows to identify patients eligible to trials with novel targeted agents.

Review: Cell Dynamics in Malignant Pleural Effusions.

Malignant pleural effusions (MPEs) are a common manifestation found in patients with lung cancer. After cytological and histological confirmation of malignancy, talc pleurodesis still remains the treatment of choice in patients with MPEs resistant to chemotherapy. Despite this, primary challenges include reduced quality of life and life expectancy in general. Therefore, a better understanding of the cell biology of MPEs, along with improvements in treatment is greatly needed. It has recently been demonstrated that MPEs may represent an excellent source for identification of molecular mechanisms within the tumor and its environment. The present review summarizes the current understanding of MPEs cells and tumor microenvironment, and particularly focuses on dissecting the cross-talk between MPEs and epithelial to mesenchymal transition (EMT), inflammation and cancer stem cells.

EMT markers in lung adenocarcinoma pleural effusion spheroid cells.

Epithelial-to-mesenchymal transition (EMT) is a process in which cells undergo a developmental switch from epithelial to mesenchymal phenotype. This process has been related to embryologic morphogenesis but also to cancer progression and metastasis. The aim of the current study was to investigate the expression of EMT-related markers in adherent and spheroid cell cultures derived from malignant pleural effusions (MPEs) of patients affected by lung adenocarcinoma. On the basis of efficient in vitro propagation, six cases of MPEs were selected and analyzed by immunocytochemistry staining for EMT markers and by RT-PCR for transcription factors known to orchestrate EMT. EMT markers immunostaining showed in spheroids a statistically significant correlation between the loss of E-cadherin immunoreactivity and overexpression of N-cadherin (P < 0.001). Likewise loss of EpCAM epithelial marker was coincident with Vimentin overexpression (P < 0.001). RT-PCR analysis of transcription factors Snail, Slug, and Twist showed a highly variable expression, although a general trend to increase was observed. Importantly, in some selected cases it was possible to establish a precise relationship between spheroid formation, EMT switch and increased upregulation of the marker related to cancer stemness such as ALDH positivity. Therefore, MPE-derived cell cultures, while recapitulating the heterogeneity of lung cancer, are a suitable system to study the mechanisms at the basis of EMT and to understand its relationship with the generation of cancer stem cells.

Towards Artificial Intelligence Applications in Next Generation Cytopathology.

Over the last 20 years we have seen an increase in techniques in the field of computational pathology and machine learning, improving our ability to analyze and interpret imaging. Neural networks, in particular, have been used for more than thirty years, starting with the computer assisted smear test using early generation models. Today, advanced machine learning, working on large image data sets, has been shown to perform classification, detection, and segmentation with remarkable accuracy and generalization in several domains. Deep learning algorithms, as a branch of machine learning, are thus attracting attention in digital pathology and cytopathology, providing feasible solutions for accurate and efficient cytological diagnoses, ranging from efficient cell counts to automatic classification of anomalous cells and queries over large clinical databases. The integration of machine learning with related next-generation technologies powered by AI, such as augmented/virtual reality, metaverse, and computational linguistic models are a focus of interest in health care digitalization, to support education, diagnosis, and therapy. In this work we will consider how all these innovations can help cytopathology to go beyond the microscope and to undergo a hyper-digitalized transformation. We also discuss specific challenges to their applications in the field, notably, the requirement for large-scale cytopathology datasets, the necessity of new protocols for sharing information, and the need for further technological training for pathologists.

Exosomal Functional Cargoes from Liquid Biopsy of Gastric Cancer: A Systematic Review of Studies With Potential Clinical Relevance.

BACKGROUND/AIM: Liquid biopsy (LB) is a promising non-invasive tool to detect cancer. Over the last few years, exosomes recruited from LB have attracted the attention of researchers for their involvement in cancer. We focused on the role of LB exosomes in gastric cancer (GC). MATERIALS AND METHODS: We investigated the world literature on exosome-encapsulated functional biomarkers (non-coding RNAs and DNAs) taken from GC patients' LBs. Only the studies exploring serum, intraperitoneal fluid or gastric lavage were included. RESULTS: As of 2022, fifty articles with an overall count of 3552 GC patients were investigated. Given the statistically significant associations with the clinicopathological categories of tumor depth, lymph node metastasis, staging class and tumor size, most exosome-mediated microRNAs, long non-coding RNAs and circular RNAs proved to exert a potentially important bioclinical role in terms of diagnosis, screening, prognosis and therapeutic targets. CONCLUSION: In the future, resorting to exosomal biomarkers taken from LB of affected patients could revolutionize the non-invasive fight against GC.

Prognostic Role of Intragastric Cytopathology and Microbiota in Surgical Patients with Stomach Cancer.

BACKGROUND: In the last decade, analysis of malignant cells and flora in gastric lavage (GL) has provided interesting data on pathogenesis of gastric cancer (GC). For this study, combining such two aspects into one cyto-microbiologic category, we tested the prognostic role of the presence/absence of cancer cells (GL1/GL0) and bacterial microbiota (MB1/MB0) in our GC population. MATERIAL AND METHODS: Between April 2012 and August 2019, 79 surgical patients with GC were prospectively investigated with the determination of GL MB. RESULTS: Compared with GL1 MB0, GL1 MB1 strongly correlated with advanced GC, portended poorer overall survival (OS) (45.8 months vs 20.5 months, P = 0.049), and resulted a significant (P = 0.008) and an independent (P = 0.013) prognostic factor unfavorable for OS. CONCLUSION: In the light of our results, the cyto-microbiologic parameter of GL MB should be used to gain a better prognosis of GC patients. Administration of antimicrobial treatment for MB1 subjects should be entertained because it could reduce the risk of oncogenesis.

Neurotrophin system activation in pleural effusions.

Neurotrophins (NTs) expression was assessed in malignant and non-malignant pleural effusions (inflammatory exudates and transudates). Enzyme-linked immunosorbent assay, in malignant exudates from small and non-small cell lung cancer (SCLC and NSCLC), detected nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3), and their levels are higher as compared with inflammatory and transudative effusions. By immunoblots, in cultured cancer cells coming from malignant pleural effusions, NTs and low- and high-affinity NT receptors were detected in a percentage of SCLC and NSCLC. Proliferation assay demonstrated that BDNF significantly increased cancer cell proliferation in vitro, on the contrary, NT-3 reduced cancer cell growth rate and NGF did not modify cell growth. Moreover, NGF protects cells from death during starvation. These effects are reverted by the addition of NT receptor antagonists. Cultured cancer cells injected into the lung of immunodeficient mice generate lung tumors expressing NTs and NT receptors. These findings suggest that NTs may be able to modulate cancer cell behavior and their growth.

Elevated Gastric Juice Carbohydrate Antigen 72.4 (Ca 72.4) Is an Independent Prognostic Factor of Poor Survival for Gastric Cancer Patients.

BACKGROUND/AIM: As of 2020, carbohydrate antigen 72.4 (Ca 72.4) has been rarely investigated in the gastric juice (GJ) of patients with gastric cancer (GC). Our aim was to analyze the significance and role of this tumor antigen in the GJ of our GC population. PATIENTS AND METHODS: Between April 2012 and July 2013, 37 patients with operable GC were prospectively investigated to determine the GJ Ca 72.4 levels before surgical manipulation. RESULTS: GJ Ca 72.4 ≥6.49 ng/ml strongly correlated with the traditional categories of aggressive cancer (advanced tumor depth and stage, lymph node invasion and metastatic lymphatic ratio, indication to adjuvant treatment). It also associated with shorter survival (p=0.049) and is, thus, suggested as an independent factor of poor prognosis in GC patients (p=0.047). CONCLUSION: The GJ Ca 72.4 parameter should be considered an indicator of an aggressive tumor phenotype and should be used in the prognostic assessment of GC patients.

Combined Analysis of Intragastric Malignant Exfoliation and Ca 72.4 Concentration in Stomach Adenocarcinoma: The "GL1 Ca 72.4" Parameter.

INTRODUCTION/OBJECTIVE: Differently from other digestive malignancies, gastric cancer (GC) pathobiology is still little known and understood. Recently, cytopathology and molecular biology on gastric juice/gastric lavage (GJ/GL) of GC patients have provided novel and interesting results in terms of screening, diagnosis, prognosis, and therapy. However, entertaining cytologic examination and molecular test as a unified solo-run test is previously unreported. Our aim was to assess the new parameter "GL Ca 72.4" for GC patients. METHODS: Between April 2012 and July 2013, GJ/GL obtained from 37 surgical GC patients were tested for the presence/absence (GL1/GL0) of exfoliated malignant cells along with the intragastric concentration of Ca 72.4 (normal value <6.49 ng/mL: Ca 72.4n; elevated level ≥6.49 ng/mL: Ca 72.4+). RESULTS: At a median follow-up of 79.3 months, all the GC alive patients were "GL0 Ca 72.4n." The "GL1 Ca 72.4+" parameter, in comparison with GL0 Ca 72.4n, strongly correlated with deeper tumor invasion (p = 0.027), severe nodal metastasis (p = 0.012), worst metastatic node ratio (p = 0.041), higher number of metastatic lymph nodes (30 vs. 20 nodes, p = 0.014), angiolymphatic invasion (p = 0.044), advanced stage (p = 0.034), and adjuvant therapy (p = 0.044). The Kaplan-Meier model showed that GL1 Ca 72.4+ subjects had shorter overall survival (OS) than GL0 Ca 72.4n cases (9.7 vs. 43.2 months, respectively, p = 0.042). At univariate analysis, the GL1 Ca 72.4+ parameter resulted a significant prognostic factor for OS (p = 0.023). CONCLUSIONS: The combined cyto-molecular parameter "GL1 Ca 72.4+" appears to be a strong indicator of aggressive tumor behavior and a significant prognostic factor of poor survival for GC patients.

Advances in Intraluminal Exfoliative Cytology of Gastric Cancer: Oncologic Implication of the Sixth Metastatic Route (Metastasis VI).

Historically, analysis of intragastric exfoliative cytology (IEC) of gastric cancer (GC) was used with a diagnostic intent only. With the successful advent of endoscopic biopsy, the rate of detection of GC has improved worldwide and, as a consequence, IEC has been progressively abandoned. Today, however, there is a renewed interest in this field of research, as witnessed by several pertinent publications. As discussed in this review, in fact, currently the importance of analyzing IEC in patients with early and advanced GC seems to reside in its clinicopathological and prognostic significance. In fact, compared to non-sloughing tumors, GC exhibiting intragastric exfoliation was recently associated with an aggressive tumor phenotype (characterized by deeper infiltration of the gastric wall, lymph nodal or distant metastases, angiolymphatic and perineural invasion) and poorer prognosis. Adoption of IEC examination in routine practice might help identify patients at higher risk of developing local recurrence and peritoneal metastasis from early and advanced GC, optimizing their treatment and improving quality of life and life expectancy.

Gastric Lavage Malignant Cells (yGL) and Hypohemoglobinemia (yAnemia) as New Systems of Tumor Regression Grading and Prognostic Prediction for Gastric Cancer After Neoadjuvant Treatment.

BACKGROUND/AIM: Although reckoned necessary for survival benefit, neoadjuvant chemotherapy (NAC) of gastric cancer (GC) patients has so far provided questionable results. Consequently, searching for new and clearer systems of response to NAC, post-NAC re-evaluation and prognostic prediction appears essential. The purpose of this study was to examine endogastric cytopathology and hemoglobin level count as new features, potentially useful for GC patients after NAC. PATIENTS AND METHODS: Between April 2012 and October 2018, 21 of 116 patients with resectable GC received NAC and were investigated for the presence of free-floating malignant cells in their gastric lavage (yGL1) and the development of hypohemoglobinia (yAnemia). RESULTS: yGL1 and yAnemia were found in 11 and 12 patients, respectively. yGL1 correlated with the traditional parameters of tumor regression (p=0.0424). Both yGL1 and yAnemia were found to be independent predictive factors of overall and progression-free survival (p≤0.0364). CONCLUSION: In the light of our results, the yGL1 and yAnemia appear two promising, simple and interesting clinicopathological features which should always be examined for better clarifying GC patients' response to NAC.

Prognosis of patients with differentiated thyroid carcinomas having a preoperative cytological report of indeterminate at low or high risk. A multicenter study.

BACKGROUND: Italian cytology system for thyroid fine-needle aspiration (FNA) includes indeterminate lesions at low- (Tir 3A) and high-risk (Tir 3B). The present retrospective multicenter study was undertaken to compare the histological type of cancers and disease-free survival in these two groups. METHODS: Eight institutions participated. Thyroid cancer patients diagnosed and followed-up after Tir 3A or Tir 3B were reviewed. Histological diagnosis was adopted as the gold standard. Patients were defined with cancer recurrence or no evidence of disease. Disease-free survival (DFS) was calculated. A non-parametric statistical analysis was used. DFS was estimated by Kaplan-Meier method and Hazard Ratio (HR) defined the slope of curves. RESULTS: Two hundred and nine patients (median DFS 24 months) were enrolled and a 6.3% of these recurred. Tir 3B group had higher age (p = 0.014), larger cancer size (p = 0.0002), shorter DFS (p = 0.003), higher number of aggressive cancers (p = 0.006), and relapse frequency double than Tir 3A. At survival curves analysis, Tir 3B group had HR of 2.37 with respect to Tir 3A. At Cox's proportional hazard regression analysis histology was the only significant predictor of relapse. CONCLUSIONS: While patients with thyroid FNA of Tir 3B should be addressed to surgery due to high likelihood of more aggressive cancer, a diagnostic surgery could be avoided in patients with Tir 3A if concurrent unsuspicious clinical features are found.

Fez1/Lzts1-deficient mice are more susceptible to N-butyl-N-(4-hydroxybutil) nitrosamine (BBN) carcinogenesis.

FEZ1/LZTS1 is a tumor suppressor gene that is frequently altered in human cancers of different histotypes. We have reported previously that LZTS1 is downregulated in high-grade bladder cancer and that its restoration suppresses tumorigenicity in urothelial carcinoma cells. To further investigate the role of LZTS1 in the development of bladder cancer, we utilized heterozygous and nullizygous Lzts1 mice in a chemically induced carcinogenesis model. Fifty-eight mice consisting of 25 Lzts1(+/+), 17 Lzts1(+/-) and 16 Lzts1(-/-) were treated with N-butyl-N-(4-hydroxybutil) nitrosamine (BBN). Results showed that there was a significant increase in neoplastic lesions in the Lzts1(+/-) (82.3%) and Lzts1(-/-) (93.8%) versus Lzts1(+/+) (8.0%) mice after BBN treatment. No difference in cancer incidence between Lzts1(+/-) and Lzts1(-/-) was observed. Collectively, these findings indicate that loss of one or both LZTS1 alleles hampers the normal defenses of urothelial cells against carcinogens, favoring bladder cancer development. Therefore, LZTS1 may become an excellent target for gene therapy in advanced bladder carcinoma.

Tissue inhibitor of metalloproteinase 2 (TIMP-2) expression in adenocarcinoma pleural effusions.

Serous effusions are frequently a clinical manifestation of metastatic disease, with lung, breast and ovarian carcinoma and mesothelioma leading the list. The diagnosis of malignant effusion signifies disease progression and is associated with a worsening patient prognosis. The ability to grow in a dense exudative fluid suggests that the malignant cells are capable of acquiring nutrients, surviving and proliferating, despite the lack of a solid-phase scaffold. During proliferation, neoplastic cells release ligands and matrix metalloproteinases (MMPs) into their environment, which dissolve the extracellular matrix (ECM). Tissue inhibitors of metalloproteinase (TIMPs) are endogenous regulators of MMPs, the principal enzymes responsible for the degradation of ECM in metastasis, and reduce their proteolytic activity. TIMP-2 has demonstrated an association between high tumor tissue expression levels and poor prognosis. The purpose of this preliminary study is to investigate, by immunocytochemistry, TIMP-2 expression in non-neoplastic and metastatic adenocarcinoma pleural effusions. We selected 16 cases of reactive mesothelio, 7 of normal mesothelio, 14 of lung adenocarcinoma, 9 from the ovary, 4 from the gastrointestinal tract and 3 from the breast. In 23/30 cases (76%), we detected adenocarcinoma cells with strong TIMP-2 expression. Positive TIMP-2 expression was found in 2/7 cases (28%) of normal and 2/16 (12%) of reactive mesothelio. A statistical association was detected between TIMP-2 expression and metastatic adenocarcinoma cells compared to reactive and normal mesothelial cells (p<0.00003). The calculated sensitivities for TIMP-2 compared to CEA and Ber-EP4 were, respectively, 76.7, 80.0 and 93.3%, and the specificities 82.6, 95.7 and 87.0%. In conclusion, immunocytochemical detection of TIMP-2 could be considered an interesting marker in metastatic adenocarcinoma pleural effusions, and could possibly be used as a component of an antibody panel in diagnostic cytopathology.

Gastric Juice MicroRNAs as Potential Biomarkers for Screening Gastric Cancer: A Systematic Review.

BACKGROUND/AIM: To date, the combination of gastroscopy with biopsy remains the only test validated for screening gastric cancer (GC). Currently, analysis of circulating microRNAs (miRNAs or miRs) is providing interesting information on GC prognosis, but since these molecules are shared by several types of cancer, its clinical use could be questionable and difficult. MicroRNAs in gastric juice (GJ) could represent a cogent alternative to screening GC by biopsy. MATERIALS AND METHODS: We investigated the pertinent literature dealing with GC GJ microRNAs through four popular search engines (PubMed, Science Direct, Scopus and Google Scholar). RESULTS: As of 2017, only four studies had been published and were all from Chinese experience. MiR-421, miR-129, miR-21, miR-106a and miR-133a were the five molecules studied in the GJ of the enrolled patients. CONCLUSION: The GJ miRNA test is reliable and reproducible. The discussed GJ miRNAs appear to be new potential biomarkers for the screening of GC.

Gastric Cancer Cells in Peritoneal Lavage Fluid: A Systematic Review Comparing Cytological with Molecular Detection for Diagnosis of Peritoneal Metastases and Prediction of Peritoneal Recurrences.

BACKGROUND/AIM: Detecting free tumor cells in the peritoneal lavage fluid of gastric cancer patients permits to assess a more accurate prognosis, predict peritoneal recurrence and select cases for a more aggressive treatment. Currently, cytology and molecular biology comprise the two most popular methods of detection that are under constant study by researchers. MATERIALS AND METHODS: We burrowed into the available literature comparing cytological with molecular detection of free intraperitoneal gastric cancer cells. PubMed, Science Direct, Scopus and Google Scholar were the search engines investigated. RESULTS: As of 2017, 51 dedicated studies have been published. Messenger RNA of carcinoembryonic antigen was the genetic target most frequently described. The genetic technique is usually superior to cytology in sensitivity (38-100% vs. 12.3-67% respectively), whereas cytological examination tends to show a slight pre-eminence in specificity (approximately 100%). CONCLUSION: So far, given the imperfection of each method, employment of both cytology and molecular examination seem to be mandatory.

Laparoscopic Intragastric Surgery for Treating Early Gastric Cancer.

BACKGROUND/AIM: Although there is an increasing number of studies on laparoscopic resection of early gastric cancer (EGC), as of 2018 no standardized strategy exists. We reviewed available literature dealing with laparoscopic intragastric (intraluminal) surgery (LIGS) conducted for patients with EGC to better define indications, benefits and limitations of this particular minimally invasive technique. MATERIALS AND METHODS: PubMed, MEDLINE, Science Direct, Scopus, Web of Science, Google Scholar and ResearchGate were the search engines investigated. Only LIGS for EGC was entertained; studies conducted for other gastric diseases were excluded. Suitable articles written in all languages were included in the review. RESULTS: As of 2018, we found 19 studies dealing with LIGS for EGC: studies on 72 humans and four pigs were identified. Among 72 human participants, there were 59 mucosal, five submucosal and one subserosal cancer. CONCLUSION: Based on our review, LIGS appears as a cogent option to endoscopic resection for treating superficial EGC.

Preoperative gastric lavage in gastric cancer patients undergoing surgical, endoscopic or minimally invasive treatment: An oncological measure preventing peritoneal spillage of intragastric cancer cells and development of related metastases.

In addition to classical metastatic pathways, recently gastric cancer was described having an alternative route called "endoluminal exfoliation". Provisional analyses demonstrated, in fact, this kind of shedding is associated with several clinico-pathological features indicative of aggressive behavior and resulted to be an independent prognostic factor entailing poor prognosis. Compared with non-sowing counterparts, in fact, patients affected with exfoliating early and advanced gastric carcinomas met with shorter overall survival, disease free survival, progression free survival and time to tumor progression. In spite of these interesting results, however, the clinico-pathological and oncological significance of this unconventional metastatic route is still to be clarified. Such an investigation is further urged by the increasing widespread employment of minimally invasive treatments for gastric cancer which include a wide spectrum of intragastric interventions and maneuvers. Indeed, endoscopic mucosal resection, endoscopic submucosal dissection, endoscopic full-thickness resection, intragastric laparoscopic surgery and hybrid procedures all take place inside of the stomach. However, iatrogenic perforations can occur during execution of these treatments leading to spillage of malignant cells from gastric to the peritoneal cavity or trocar insertion sites. Furthermore, many other gastric conditions and interventions can collide with endogastric presence of floating cancer cells: spontaneous ulceration or perforation, laparotomy surgery, gastrointestinal occlusion, diverticula. Viability, migration and intraluminal transportability of the intragastric floating cancer cells represents another original and intriguing topic. All these considerations led us to entertain the hypothesis that removing the exfoliated cancer cells from the gastric lumen could save patients from the dreaded potential risk of spillage. Performing gastric lavage before starting any kind of tumor intervention could be the most appropriate procedure to adopt with prophylactic intent. Should our speculation prove to be clinically significant, preoperative gastric lavage should be pointed out as a simple but cogent method useful for preventing oncological mishaps such as spillage of gastric cancer cells and development of related recurrences or metastases.