Proteomic profiles of peritoneal fluid-derived small extracellular vesicles correlate with patient outcome in ovarian cancer.

Cancer-derived small extracellular vesicles (sEVs) are capable of modifying the tumor microenvironment and promoting tumor progression. Ovarian cancer (OvCa) is a lethal malignancy that preferentially spreads through the abdominal cavity. Thus, the secretion of such vesicles into the peritoneal fluid could be a determinant factor in the dissemination and behavior of this disease. We designed a prospective observational study to assess the impact of peritoneal fluid-derived sEVs (PFD-sEVs) in OvCa clinical outcome. For this purpose, 2 patient cohorts were enrolled: patients with OvCa who underwent a diagnostic or cytoreductive surgery and nononcological patients, who underwent abdominal surgery for benign gynecological conditions and acted as the control group. Systematic extraction of PFD-sEVs from surgical samples enabled us to observe significant quantitative and qualitative differences associated with cancer diagnosis, disease stage, and platinum chemosensitivity. Proteomic profiling of PFD-sEVs led to the identification of molecular pathways and proteins of interest and to the biological validation of S100A4 and STX5. In addition, unsupervised analysis of PFD-sEV proteomic profiles in high-grade serous ovarian carcinomas (HGSOCs) revealed 2 clusters with different outcomes in terms of overall survival. In conclusion, comprehensive characterization of PFD-sEV content provided a prognostic value with potential implications in HGSOC clinical management.

Reliably making the primary diagnosis of mesothelioma utilizing serous fluid cytology specimens: an institutional experience.

INTRODUCTION: The diagnosis of mesothelioma has historically been challenging, especially on serous fluid cytology (SFC). Distinguishing between reactive and neoplastic mesothelial cells can be difficult on cytomorphology alone. However, additional ancillary tests, such as BRCA1 associated protein-1 immunohistochemistry and fluorescence in situ hybridization for cyclin-dependent kinase inhibitor 2A deletion, can provide a sensitive and highly specific method of proving malignancy. MATERIALS AND METHODS: SFC specimens diagnosed as mesothelioma, suspicious for mesothelioma (SM), and atypical mesothelial cells (AMCs) since 2012 were identified by querying the laboratory information system. Clinical data and pathologic parameters were gathered. RESULTS: One hundred ten cases of mesothelioma, SM, and AMC were identified. Of these, 61 cases had a definitive diagnosis of mesothelioma on SFC. Average age at SFC diagnosis was 67 years (26-87 years), with most patients being male (67%). Out of the 61 cases, 11 cases (18%) had an initial diagnosis of mesothelioma made on SFC specimens, with 5 of these 11 cases being in patients that never received a histologic diagnosis of mesothelioma. Ancillary studies were utilized in all 11 cases. An initial diagnosis of metastatic mesothelioma was made on SFC in 9 cases (15%). For 6 of these 9 cases, the SFC diagnosis was the sole diagnosis of metastatic mesothelioma without a companion histologic diagnosis. In addition, 15 cases were diagnosed as SM, with 11 of these cases following a definitive mesothelioma diagnosis. Thirty-four cases were diagnosed as AMC, with 27 cases following a definitive mesothelioma diagnosis. CONCLUSIONS: The diagnosis of mesothelioma can be reliably made on SFC with the appropriate cytomorphology criteria and/or confirmatory ancillary testing.

Overexpression of Fut 2, 4, and 8, and nuclear localization of Fut 4 in ovarian cancer cell lines induced by ascitic fluids from epithelial ovarian cancer patients.

Fucosyltransferases (Fut) regulate the fucosylation process associated with tumorogenesis in different cancer types. Ascitic fluid (AF) from patients diagnosed with advanced stage of epithelial ovarian cancer (EOC) is considered as a dynamic tumor microenvironment associated with poor prognosis. Previous studies from our laboratory showed increased fucosylation in SKOV-3 and OVCAR-3, cancer-derived cell lines, when these cells were incubated with AFs derived from patients diagnosed with EOC. In the present work we studied three fucosyltransferases (Fut 2, Fut 4, and Fut 8) in SKOV-3, OVCAR-3 and CAOV-3 cell lines in combination with five different AFs from patients diagnosed with this disease, confirming that all tested AFs increased fucosylation. Then, we demonstrate that mRNAs of these three enzymes were overexpressed in the three cell lines under treatment with AFs. SKOV-3 showed the higher overexpression of Fut 2, Fut 4, and Fut 8 in comparison with the control condition. We further confirmed, in the SKOV-3 cell line, by endpoint PCR, WB, and confocal microscopy, that the three enzymes were overexpressed, being Fut 4 the most overexpressed enzyme compared to Fut 2 and Fut 8. These enzymes were concentrated in vesicular structures with a homogeneous distribution pattern throughout the cytoplasm. Moreover, we found that among the three enzymes, only Fut 4 was located inside the nuclei. The nuclear location of Fut 4 was confirmed for the three cell lines. These results allow to propose Fut 2, Fut 4, and Fut 8 as potential targets for EOC treatment or as diagnostic tools for this disease.

Diagnosis of peritoneal metastasis in an unruptured hepatocellular carcinoma on ascitic fluid cytology: A rare scenario with brief review of literature.

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy in adults occurring in a background of cirrhosis. Peritoneal dissemination of HCC is an unusual presentation with an incidence of 2%-16%. Peritoneal metastasis of an unruptured HCC is extremely uncommon. Despite low yield, ascitic fluid cytology serves as a valuable tool for diagnostic evaluation in a patient of cirrhosis with suspicion of malignant transformation. We present a rare case scenario in an elderly female with cirrhosis where the diagnosis of peritoneal metastasis was established on ascitic fluid cytology and confirmed by immunocytochemistry. This report illustrates the unique clinical presentation of an unruptured HCC with its cytological features and a brief review of literature.

The diagnostic accuracy and prognostic implication of pelvic and peritoneal fluid cytology specimens in ovarian clear cell carcinoma.

INTRODUCTION: Ovarian clear cell carcinoma (OCCC) is a rare subtype of ovarian epithelial carcinoma. Patients with low-stage disease have an excellent prognosis, while the prognosis for those with high-stage disease is poor. Neoplastic cells in abdominopelvic washings upstages the patient to at least FIGO 1C3. Positive cytology confers a worse prognosis when compared to similar stage patients with negative cytology. This study aims to investigate the diagnostic performance of abdominopelvic fluid cytology specimens in cases with pure OCCC and reaffirm the importance of accurate cytologic detection and its impact on patient prognosis. MATERIALS AND METHODS: The laboratory information system was queried to identify all patients treated for ovarian clear cell carcinoma at our institution over a period of 20 years with a companion abdominopelvic fluid cytology specimen at the time of surgical resection. Cases were sorted by the FIGO stage of the corresponding oophorectomy specimen. Cytology results, patient demographics, fluid volume, immunohistochemical results, and follow-up data were recorded. RESULTS: A total of 143 cases were identified. The overall detection rate was 38%, with 54 of 143 cases positive for malignancy. Cytologic detection rates increased as FIGO stages increased. Fifty percent of stage 1C cases were upstaged on cytology alone. Ascites fluids performed better among stage 1 cases compared to pelvic wash specimens (77% detection rate versus 23%). Stage 1 patients with positive cytology trended towards a worse prognosis compared to those with negative cytology. CONCLUSIONS: Positive cytology in low stage cases of OCCC has significant prognostic and therapeutic implications. Our large cohort further underscores the importance of accurate cytologic detection and subsequent staging in this setting.

Bugs' eyes and black monsters: Ascitic fluid cytology in an elderly male with hematochezia.

Anorectal malignant melanomas are rare, accounting for less than 2% of all melanomas. Malignant effusions developing secondary to malignant melanoma are highly uncommon. Herein, we present the cytomorphological features of a metastatic anorectal malignant melanoma presenting with ascites at the initial clinical presentation.

Homologous recombination deficiency (HRD) testing on cell-free tumor DNA from peritoneal fluid.

BACKGROUND: Knowing the homologous recombination deficiency (HRD) status in advanced epithelial ovarian cancer (EOC) is vital for patient management. HRD is determined by BRCA1/BRCA2 pathogenic variants or genomic instability. However, tumor DNA analysis is inconclusive in 15-19% of cases. Peritoneal fluid, available in > 95% of advanced EOC cases, could serve as an alternative source of cell-free tumor DNA (cftDNA) for HRD testing. Limited data show the feasibility of cancer panel gene testing on ascites cfDNA but no study, to date, has investigated HRD testing. METHODS: We collected ascites/peritoneal washings from 53 EOC patients (19 from retrospective cohort and 34 from prospective cohort) and performed a Cancer Gene Panel (CGP) using NGS for TP53/HR genes and shallow Whole Genome Sequencing (sWGS) for genomic instability on cfDNA. RESULTS: cfDNA was detectable in 49 out of 53 patients (92.5%), including those with limited peritoneal fluid. Median cfDNA was 3700 ng/ml, with a turnaround time of 21 days. TP53 pathogenic variants were detected in 86% (42/49) of patients, all with HGSOC. BRCA1 and BRCA2 pathogenic variants were found in 14% (7/49) and 10% (5/49) of cases, respectively. Peritoneal cftDNA showed high sensitivity (97%), specificity (83%), and concordance (95%) with tumor-based TP53 variant detection. NGS CGP on cftDNA identified BRCA2 pathogenic variants in one case where tumor-based testing failed. sWGS on cftDNA provided informative results even when tumor-based genomic instability testing failed. CONCLUSION: Profiling cftDNA from peritoneal fluid is feasible, providing a significant amount of tumor DNA. This fast and reliable approach enables HRD testing, including BRCA1/2 mutations and genomic instability assessment. HRD testing on cfDNA from peritoneal fluid should be offered to all primary laparoscopy patients.

Techniques of staging laparoscopy and peritoneal fluid assessment in gastric cancer: a systematic review.

BACKGROUND: Staging laparoscopy for gastric cancer is recommended to assess the tumor's locoregional extension and exclude peritoneal disease. As there is no consensus on optimizing the procedure's diagnostic accuracy, we aimed to systematically review the literature on operative techniques, followed by peritoneal lavage fluid assessment in gastric cancer patients. Specifically, we sought to indicate the most common characteristics of the procedure and cytological evaluation. METHODS: This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The protocol for this systematic review was registered on PROSPERO database (CRD: 42022306746). On September 2022, a search was carried out using Embase, Medline ALL, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection. RESULTS: The search identified 1632 studies on staging laparoscopy and 2190 studies on peritoneal fluid assessment. Some 212 studies were included. Open Hasson was the method of choice in accessing the peritoneal cavity in 65% of the studies, followed by establishing a pneumoperitoneum at 10-12 mmHg in 52% of reports. Most frequently, the patient was positioned supine (70%), while a 30° scope and three ports were used to assess the peritoneal cavity clockwise (72%, 77%, and 85%, respectively). Right and left upper abdomen quadrants were the predominant area of laparoscopic exploration (both 65%), followed by the primary tumor region (54%), liver and pelvis (both 30%), and small bowel and spleen (19% and 17%, respectively). Regions of peritoneal lavage and aspiration were limited to the pelvis (50%), followed by right and left upper abdomen quadrants (37.5% and 50%, respectively). No studies compared different methods of operative techniques or analysis of ascites/fluid. CONCLUSIONS: This study indicates a high heterogeneity in the technique of staging laparoscopy and peritoneal fluid assessment in gastric cancer patients. Further research and initiatives to reach a consensus on the standardization of the procedure are warranted.

Randomized crossover trial of 'Roll-over' technique of abdominal paracentesis versus standard technique in suspected malignant ascites.

BACKGROUND: The sensitivity of single abdominal paracentesis for diagnosis of peritoneal carcinomatosis (PC) varies from 40-70%. We hypothesized that rolling-over the patient before paracentesis might improve the cytological yield. RESEARCH DESIGN AND METHODS: This was a single center pilot study with a randomized cross-over design. We compared the cytological yield of fluid obtained by roll-over technique (ROG) with standard paracentesis (SPG) in suspected PC. In the ROG group, patients were rolled side-to-side thrice, and the paracentesis was done within 1 minute. Each patient served as their own control, and the outcome assessor (cytopathologist) was blinded. The primary objective was to compare the tumor cell positivity between SPG and ROG groups. RESULTS: Of 71 patients, 62 were analyzed. Of 53 patients with malignancy-related ascites, 39 had PC. Most of the tumor cells were adenocarcinoma (30, 94%) with one patient each having suspicious cytology and one having lymphoma. The sensitivity for diagnosis of PC was (31/39) 79.49% in SPG group and (32/39) 82.05% in ROG group (p = 1.00). The cellularity was similar between both the groups (good cellularity in 58% of SPG and 60% of ROG, p = 1.00). CONCLUSIONS: Rollover paracentesis did not improve the cytological yield of abdominal paracentesis. TRIAL REGISTRATION: CTRI/2020/06/025887 and NCT04232384.

Cytology of Benign Peritoneal Fluids and Pelvic Washing Specimens: Diagnostic Cytomorphologic Features and Pitfalls.

BACKGROUND: Pelvic washing and peritoneal fluid cytology specimens are used to detect peritoneal spread of malignancies. In most cases, identification of malignancy in these specimens is straightforward, but benign processes may occasionally mimic neoplasia and cause diagnostic difficulty. SUMMARY: In this article, we perform a focused review of common benign entities encountered in pelvic washing and peritoneal fluid specimens during routine practice which may cause difficulty and discuss helpful features for avoiding diagnostic pitfalls. KEY MESSAGES: Application of strict cytomorphologic criteria, along with judicious use of ancillary studies and correlation with clinical, intraoperative, radiologic, and other pathologic findings, can help resolve most problematic cases.

Categorisation of peritoneal serous effusions using the International System for Reporting Serous Fluid Cytopathology-A study on gynaecological samples.

BACKGROUND: Cytology of serous effusions is an indispensable diagnostic tool for the diagnosis of non-neoplastic as well as neoplastic effusions, aiding in the categorisation, staging, and prognostication of the patient. This study focuses on reclassifying cases of peritoneal fluid cytology following the International System for Reporting Serous Fluid Cytopathology (TIS), highlighting various challenges encountered and adding to the body of data regarding the risk of malignancy (ROM), focussing on peritoneal effusions due to gynaecological causes. METHODS: Peritoneal effusion samples were retrieved from our department's archives and reclassified according to the TIS. The ROM for each category was calculated based on available surgical follow-up. RESULTS: A total of 818 peritoneal effusions were studied. Following the definitions and guidelines of the TIS, the cases were reclassified with 125 (15.2%) in the category of non-diagnostic (ND), 595 (72.7%) as negative for malignancy (NFM), 26 (3.2%) as atypia of undetermined significance (AUS), 12 (1.5%) as suspicious for malignancy (SFM), and 60 (7.3%) as malignant (MAL). The respective ROM values for each category were 16.9%, 12.1%, 50%, 80%, and 100%, respectively. By considering the MAL and SFM groups as positive, and the ND, NFM, and AUS groups as negative, the diagnostic accuracy, sensitivity, specificity, and positive and negative predictive values were determined as 85.2%, 36.7%, 99.1%, 91.7%, and 84.5%, respectively. CONCLUSIONS: Peritoneal cytology categorisation following the proposed TIS offered a practical approach for categorisation of the fluids received. The ROMs reported in our study were mostly concordant with those published according to the TIS.

Practical Approach to the Evaluation of Malignant Peritoneal Fluids in the Setting of Gynecologic Neoplasms.

BACKGROUND: Evaluation of peritoneal fluid cytology, either from ascitic fluids or as a result of peritoneal washings, is a fundamental aspect in the evaluation of women presenting with clinically concerning or histologically confirmed gynecologic neoplasms. SUMMARY: Ascitic fluid samples are often the initial and only source of diagnostic material in women presenting with gynecologic malignancies, and important therapeutic decisions will result from the information provided in the cytology report. On the other hand, cytologic evaluation of peritoneal washing specimens obtained during surgical excision of a presumed gynecologic neoplasm provides crucial information to the clinical team regarding tumor staging, often with significant therapeutic implications. While recognition of high-grade tumors in either of these samples is generally straightforward, low-grade tumors and unusual neoplasms can prove to be more difficult to recognize, differentiate from benign mimics, and correctly diagnose, particularly in low-cellularity specimens. Even with high-grade tumors, a mere diagnosis of "positive for malignancy" in diagnostic ascitic fluid specimens might not suffice to guide clinical management, and the use of ancillary techniques to further and more definitively characterize the lesional cells is required. KEY MESSAGES: This review will focus on the clinically relevant issues surrounding interpretation of peritoneal fluid cytology specimens in the setting of gynecologic neoplasms, making emphasis on the salient cytomorphologic and immunocytochemical features of the various neoplastic processes, in an attempt to provide a practical yet effective guide on how to best evaluate, diagnose, and report these samples.

Utility of Molecular Analysis of Peritoneal Fluid in Staging Laparoscopy of Advanced Esophagogastric Junction and Gastric Cancer Prior to Neoadjuvant Treatment.

PURPOSE: Molecular analysis of peritoneal fluid in staging laparoscopy of gastric cancer is performed to improve the detection of free intraperitoneal tumor cells. Nevertheless, its significance is controversial, especially in patients with negative cytology but positive molecular analysis. The aim of this study was to analyze the sensitivity of molecular analysis and its prognostic value. METHODS: A retrospective analysis from April 2011 to October 2019 was performed. Cytology (Cyt) and molecular analysis were analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) of the carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) tumor makers. RESULTS: During the study period, 138 staging laparoscopies were performed. Macroscopic carcinomatosis was found in 12.3%. Of the remaining 87.7%, 9.9% were Cyt + and 11.6% were Cyt- RT-PCR + . Of the latter, 9 responded to chemotherapy and underwent radical surgery. The sensitivity of cytology and molecular analysis was 0.70 and 0.76, respectively (p = 0.67). The 2-year overall survival (OS) of Cyt- RT-PCR + vs. Cyt + was similar (p = 0.1). The 2-year OS of Cyt-RT-PCR + subgroup who underwent radical surgery vs. Cyt-RT-PCR- patients was similar (p = 0.69), but disease-free survival was shorter in the first group (p = 0.005). CONCLUSION: Our results show that the sensitivity of molecular analysis is similar to that of cytology. The prognostic value of positive molecular analysis was similar to positive cytology in terms of 2-year overall survival, except in the subgroup of operated patients in whom the overall survival was similar to that of those with a negative molecular analysis, albeit with a shorter disease-free survival.

Meta-analyses reveal serum or plasma Interleukin-6 as a biomarker for malignant ovarian neoplasia.

BACKGROUND: Interleukin-6 (IL-6) has been implicated in various malignancies, including ovarian cancer. However, mixed results have been observed regarding IL-6 levels in different ovarian conditions. This meta-analysis was performed to determine IL-6 levels in the peritoneal fluid and peripheral blood among patients with various adnexal masses. METHODS: Most popular English databases were searched using a predefined search formula. All studies comparing IL-6 levels in plasma, serum or peritoneal fluid of patients with benign tumors, ovarian neoplasms, and healthy controls were included based on inclusion and exclusion criteria. RESULTS: 5953 patients from 22 primary publications raging from 1994 to 2021 were included in the meta-analyses. A pooled IL-6 Mean Difference (MD) of 41 pg/mL for malignant tumors compared to benign ones, with a Confidence Interval (CI) between 19.8 and 62.2, a Z-score of 3.79, and statistical significance with a p = 0.0002 was observed. Pooled results for healthy versus benign ovarian conditions showed an MD of 5.45 pg/mL for serum or plasma IL-6 measurements in favor of benign tumors (CI:0.66-10.25, Z = 2.23 and p = 0.03). The analysis showed an MD for IL-6 levels of 19.59 pg/mL for healthy controls versus malignant ovarian tumors. Peritoneal fluid measurements regarding IL-6's levels showed no significant difference between benign or malignant masses. DISCUSSION/CONCLUSIONS: Higher levels of plasma or serum IL-6 in ovarian neoplasia patients compared to benign conditions or healthy controls identify IL-6 as a discerning factor between benign or malignant ovarian tumors and a potential biomarker for ovarian malignancy.

Cytomorphological analysis of effusion fluids for detection of malignant cells in a tertiary care hospital in northern India.

INTRODUCTION: All body cavities are lined by monolayered mesothelial cells and contain a minimal amount of fluid for lubrication and for protecting the underlying viscera. The peritoneal, pleural, cerebrospinal, sputum, urine, and pericardial fluids comprise the major chunk of body fluids. MATERIAL AND METHODS: The study was conducted in the Department of Pathology of a tertiary care hospital in northern India, over a period of 1 year, from January 2021 to December 2021. A total of 241 samples were included in the study. RESULTS: Out of the 241 samples studied, 99 were peritoneal fluid, 94 were pleural fluids, 29 were CSF, and 18 were sputum samples. Maximum number of patients affected were in the age group of 41-50 years. Female preponderance was seen with male to female ratio of 1:1.7. A total of 143/241 cases (59.33%) were of transudative nature and 98/241 (27.8%) cases were exudative. Out of 241 cases, 43 (17.84%) were neoplastic, 190 (78.83%) were non-neoplastic, four (1.65%) were suspicious for malignancy, and four (1.65%) were where no opinion was possible. Peritoneal fluid was the most frequently encountered fluid accounting for 99 cases (41.07%). Adenocarcinoma was the most common malignancy accounting for 29 cases (67.44%) out of 43 malignant effusions in the present study. CONCLUSION: Cytological evaluation of body fluids is of significant utility in diagnostic medicine as it allows us to distinguish between benign and malignant etiologies and at the same time offers rapid diagnosis and staging of metastatic disease.

Immunohistochemistry on cell blocks for diagnosis of malignancy in abdomino-pelvic lesions and ascitic fluid cytology at a rural cancer center: A paradigm shift in cancer management.

Background: Cell block preparation is routine practice in cytopathology these days because of its pivotal role in increasing diagnostic yield and ancillary studies. In the present era of personalized medicine in oncology, ancillary techniques such as immunohistochemistry (IHC) and molecular analysis are gaining more importance. Methods: A retrospective study was conducted in the Department of Pathology, over 6 months, which included 144 cases of Fine Needle Aspiration Cytology (FNAC) of abdominopelvic masses and 105 cases of ascitic fluids. Cell blocks and conventional smears were prepared simultaneously in all cases. IHC was applied on cell blocks and analyzed. Results: IHC was performed on cell blocks in 76 cases of FNA and 53 cases of ascitic fluids. Based on IHC, liver lesions (50 cases) were categorized into metastatic carcinomas with a suggested primary site (45.0%), hepatocellular carcinoma (12.2%), neuroendocrine tumors (16.3%), and malignant melanoma (2%). Using MOC-31 and WT-1, ascitic fluid samples were categorized into benign and malignant. Forty-one out of 53 cases of fluids were diagnosed as metastatic adenocarcinomas with the ovary as the most common primary site. Conclusion: A panel of IHC markers, though not specific alone when applied to cell blocks in a careful clinical and morphological context leads to a rapid and accurate diagnosis. This in turn obviates the need for biopsy in severely ill patients. An astute pathologist can provide accurate results with judicious use of IHC on cell blocks and may bring a sigh of relief for many cancer patients by averting the need for biopsy.

Diagnóstico, manejo y tratamiento de pacientes con peritonitis secundaria en una unidad de cirugía general / Diagnosis, management and treatment of patients with secondary peritonitis in a general surgery unit

La peritonitis es una inflamación aguda o crónica del peritoneo que generalmente tiene un origen infeccioso. Existen varios tipos, siendo la de tipo secundario la más frecuente. El término peritonitis secundaria se define como la inflamación localizada o generalizada de la membrana peritoneal causada por infección polimicrobiana posterior a la ruptura traumática o espontánea de una víscera o secundaria a la dehiscencia de anastomosis intestinales. Esta entidad se caracteriza por la presencia de pus en la cavidad peritoneal o de líquido; que, en el estudio microscópico directo, contiene leucocitos y bacterias. El tratamiento de esta patología constituye una urgencia y puede ser de tipo clínico y/o quirúrgico. El objetivo del manejo operatorio se basa en identificar y eliminar la causa de la infección, recoger muestras microbiológicas, realizar una limpieza peritoneal y prevenir la recidiva. El tratamiento clínico se ocupa de las consecuencias de la infección mediante la reanimación perioperatoria y el tratamiento antibiótico1. A pesar de los avances en diagnóstico, procedimientos quirúrgicos, terapia antimicrobiana y cuidados intensivos, la mortalidad asociada con la peritonitis secundaria grave es aún muy alta. El pronóstico y el manejo oportuno representan la clave para mejorar la sobrevida y reducir la mortalidad asociada a infecciones intraabdominales extensas2. Es importante establecer lineamientos en cuanto al diagnóstico, manejo antibiótico y pautas de tratamiento quirúrgico para disminuir la morbilidad y mortalidad asociada a esta enfermedad. Palabras clave: Peritonitis; Peritoneo; Cavidad Abdominal/cirugía; Cavidad Peritoneal; Líquido Ascítico/patología; Procedimientos Quirúrgicos Operativos.

Peritonitis is an acute or chronic inflammation of the peritoneum that generally has an infectious origin. There are several types, with secondary peritonitis being the most frequent. The term secondary peritonitis is defined as localized or generalized inflammation of the peritoneal membrane caused by polymicrobial infection following traumatic or spontaneous rupture of a viscus or secondary to dehiscence of intestinal anastomoses. This entity is characterized by the presence of pus in the peritoneal cavity or fluid which, on direct microscopic examination, contains leukocytes and bacteria. The treatment of this pathology constitutes an emergency and can be clinical and/or surgical. The aim of operative management is based on identifying and eliminating the cause of the infection, collecting microbiological samples, performing peritoneal cleansing and preventing recurrence. Clinical management deals with the consequences of the infection by perioperative resuscitation and antibiotic treatment1 . Despite advances in diagnosis, surgical procedures, antimicrobial therapy and intensive care, mortality associated with severe secondary peritonitis is still very high. Prognosis and timely management represent the key to improving survival and reducing mortality associated with extensive intra-abdominal infections2. It is important to establish guidelines for diagnosis, antibiotic management and surgical treatment guidelines to reduce the morbidity and mortality associated with this disease.

Hondrosarcoma of the chest with intraabdominal distribution (case report).

A rare clinical observation of chondrosarcoma metastasis into the abdominal cavity with a specific metastatic ascitic fluid is presented. Chondrosarcomas that occur as a result of malignant transformation of benign chondroma are quite rare. Even less often in the literature, cases of chondrosarcoma metastases are described, especially in a peritoneum with the presence of metastatic ascites. The article describes a case of metastatic ascites in a 38-year old patient with chondrosarcoma, which developed against the background of previously resected rib chords. The article describes the cytological signs of chondrosarcoma in ascitic fluid.

Liquid biopsy using ascitic fluid and pleural effusion supernatants for genomic profiling in gastrointestinal and lung cancers.

BACKGROUND: Precision medicine highlights the importance of incorporating molecular genetic testing into standard clinical care. Next-generation sequencing can detect cancer-specific gene mutations, and molecular-targeted drugs can be designed to be effective for one or more specific gene mutations. For patients with special site metastases, it is particularly important to use appropriate samples for genetic profiling. This study aimed to determine whether genomic profiling using ASC and PE is effective in detecting genetic mutations. METHODS: Tissues, plasma, ascites (ASC) supernatants, and pleural effusion (PE) samples from gastrointestinal cancer patients with peritoneal metastasis and lung cancer patients with pleural metastasis were collected for comprehensive genomic profiling. The samples were subjected to next-generation sequencing using a panel of 59 or 1021 cancer-relevant genes panel. RESULTS: A total of 156 tissues, 188 plasma samples, 45 ASC supernatants, and 1 PE samples from 304 gastrointestinal cancer patients and 446 PE supernatants, 122 tissues, 389 plasma samples, and 45 PE sediments from 407 lung cancer patients were analyzed. The MSAF was significantly higher in ASC and PE supernatant than that in plasma ctDNA (50.00% vs. 3.00%, p < 0.0001 and 28.5% vs. 1.30%, p < 0.0001, respectively). The ASC supernatant had a higher actionable mutation rate and more actionable alterations than the plasma ctDNA in 26 paired samples. The PE supernatant had a higher total actionable mutation rate than plasma (80.3% vs. 48.4%, p < 0.05). The PE supernatant had a higher frequency of uncommon variations than the plasma regardless of distant organ metastasis. CONCLUSION: ASC and PE supernatants could be better alternative samples when tumor tissues are not available, especially in patients with only peritoneal or pleural metastases.

Identifying the primary site of malignancy in carcinomatous serous effusions using immunocytochemistry.

INTRODUCTION: Malignant effusions are commonly encountered in day-to-day cytology practice. Determining the primary site of malignancy in carcinomatous effusions is a Herculean task. Cytology coupled with immunocytochemistry (ICC) is often found to be helpful in this context. MATERIALS AND METHODS: This study was conducted to evaluate the diagnostic utility of ICC on sections from cell blocks (CBs) in the detection of the primary site of origin in cases of metastatic carcinomatous effusions. To determine the origin of the primary tumour, TTF1 (lung), PAX-8 (ovary), CDX2 (colorectal), GATA3 (breast), and CK19 (pancreaticobiliary) were employed, depending on the clinical and radiological findings, and serum tumour markers. RESULTS: A total of 13,459 serous effusion samples were received for cytological evaluation from January 2017 to December 2021, of which 2708 (20.1%) were carcinomatous effusions. Out of these, 1044 (38.5%), 1611 (59.5%), and 53 (2.0%) were from pleural, peritoneal and pericardial cavities, respectively. Of these, the majority were adenocarcinoma. ICC was performed in 309 (11.4%) cases. The ovary was the most common primary site in 179 cases (57.9%), followed by the lung (75, 24.3%), pancreaticobiliary system (12, 3.9%), colon/rectum (8, 2.6%), breast (6, 1.9%), prostate (2, 0.6%) and kidney (1, 0.3). The lung was the most common primary site in pleural (67/113, 59.3%) and pericardial (6/8, 75%) effusions. The ovary (168/188, 89.4%) was the most common primary site for carcinomatous effusions in the peritoneal cavity. However, in 17 (5.5%) cases, the exact primary site could not be established. CONCLUSIONS: Judicious and methodical use of ICC on CBs helps to identify the primary site of the tumour in most carcinomatous effusions. This is of immense help to the treating clinician in directing appropriate therapy.