Low-grade Mucinous Neoplasm Research Articles

A Low-Grade Appendiceal Mucinous Neoplasm Mimicking a Hydrosalpinx: A Case Report and Review of the Literature

Introduction: A Low-Grade Mucinous Neoplasm (LAMN), formerly known as “mucocele” or “cystadenoma,” is a non-invasive and rare appendiceal tumor, representing 0.2-0.7% of all appendix specimens. Case Report: A 31-year-old female patient who was suffering from chronic right lower quadrant abdominal pain was submitted to an exploratory laparotomy for a presumed right hydrosalpinx. A low-grade mucinous neoplasm of the appendix was discovered and the patient underwent an appendectomy. Discussion: A review of the current literature was performed regarding LAMNs. Conclusion: Further evidence is required in order to address the controversial issues of the pre-operative diagnosis of a LAMN, the extent of surgery performed and the questions regarding fertility preservation in young women.

Critical appraisal of total gastrectomy plus total colectomy with hyperthermic intraperitoneal chemotherapy as a treatment for advanced pseudomyxoma peritonei

AbstractBackgroundThe absolute requirement for a long‐term favorable result with cytoreductive surgery for pseudomyxoma peritonei is a complete resection of all visible disease. A combination of parietal peritonectomy procedures and visceral resections is required for this to occur. The cytoreductive surgery is supplemented by hyperthermic intraperitoneal chemotherapy.MethodsWe searched our database and secured files for patients who required a total gastrectomy and a total colectomy to achieve a complete cytoreductive surgery. Survival of low‐grade mucinous neoplasm (LAMN) and mucinous appendiceal adenocarcinoma (MACA) histologies were determined. Clinical and histologic variables were assessed for their impact on survival.ResultsThirteen of 450 patients (2.9%) with LAMN histology and 14 of 186 patients (7.5%) with MACA histology had these visceral resections. Median survival of these 27 patients was 10 years. LAMN and MACA patients showed the same survival. For LAMN histology, this requirement for extensive visceral resection markedly reduced survival (p < 0.0001). For MACA, there was no adverse impact on survival (p = 0.4359). Class 4 adverse events caused reduced survival (p = 0.0014).ConclusionsA 10‐year median survival accompanies total gastrectomy plus total colectomy for advanced pseudomyxoma peritonei. Systemic chemotherapy and class 4 adverse events reduced survival.

Analysis of causes and prognostic impact of tube occlusion during hyperthermic intraperitoneal chemotherapy for appendiceal pseudomyxoma peritonei

BackgroundAppendiceal pseudomyxoma peritonei (PMP), a rare tumor from mucinous appendiceal origins, is treated with Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC). However, tubing blockages during HIPEC treatment pose a common challenge, impeding the smooth progression of therapy. Few studies to date have explored the incidence and risk factors of tube occlusion during HIPEC in patients with appendiceal PMP, as well as its adverse impact on postoperative complications.MethodsFrom October 2017 to June 2023, a total of 80 patients with appendiceal PMP undergoing combined CRS and HIPEC were included in this study. Tubing blockage events were strictly defined, with patients experiencing blockages during HIPEC treatment allocated to the study group, while those with unobstructed perfusion were assigned to the control group. A comparative analysis was conducted between the two groups regarding post-HIPEC health assessments and occurrence of complications. Risk factors for luminal occlusion during closed HIPEC procedures were identified through univariate and multivariate analysis of data from 303 HIPEC treatments.ResultsTubing blockages occurred in 41 patients (51.3%). The study group experienced prolonged gastrointestinal decompression time (4.1 ± 3.0 vs. 2.5 ± 1.7 days, P = 0.003) and prolonged time to bowel movement (6.1 ± 2.3 vs. 5.1 ± 1.8 days, P = 0.022) compared to the control group. There was no significant difference in the incidence of complications between the two groups. The 1-year survival rate postoperatively was 97%, and the 3-year survival rate was 81%, with no association found between tubing blockage and poorer survival. Additionally, In 303 instances of HIPEC treatment among these 80 patients, tube occlusion occurred in 89 cases (89/303, 29.4%). Multivariable logistic regression analysis revealed age, diabetes, hypertension, and pathology as independent risk factors for tube occlusion.ConclusionTubing blockages are a common occurrence during HIPEC treatment, leading to prolonged postoperative gastrointestinal functional recovery time. When patients are elderly and have concomitant hypertension and diabetes, along with a histological type of low-grade mucinous tumor, the risk of tube occlusion increases. However, this study did not find a significant correlation between tubing blockage and the incidence of postoperative complications or overall patient survival.

Abstract 5480: Single cell and spatial transcriptomic profile of appendiceal tumour peritoneal disease

Abstract Introduction: Appendiceal tumors (AT) are rare and often develop peritoneal disease (PD), with 5 year survival of 15-63% for high grade adenocarcinomas (HG) and 46-96% for low grade mucinous neoplasms (LG). While the mainstay of treatment is cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC), the role of systemic chemotherapy is less clear with limited biological characterization of AT and its tumor microenvironment (TME). The purpose of this study was to evaluate the TME of AT PD. Here we present an atlas of AT PD cells alongside a spatially resolved transcriptomic profile comparing HG and LG. Methods: We collected tissue from 29 patients with AT PD during CRS prior to HIPEC (18 LG, nine HG and two no tumor control). We performed comprehensive single-cell RNA sequencing (38224 cells) on fresh tissue specimens from nine patients (four HG, five LG), and whole transcriptome spatial analysis (>18000 genes) using the GeoMx Digital Spatial Profiler on formalin-fixed paraffin-embedded tissue from 22 patients (five HG, 13 LG). In the spatial profiling, we used anti-CK20, anti-CD45 and SYTO 83 as morphology markers to select areas of interest (AOIs): tumor (CK20), immune (CD45) and stroma (non-CK20/CD45). Analyses were performed with R and a false discovery rate threshold of 0.05. Results: Single-cell RNA sequencing showed that both LG and HG have a preponderance of T-lineage cells including CD8, CD4 and NK T-cells. Both LG and HG tumors display association of mesothelial cells with cancer-associated fibroblasts (CAF), and CAF subsets expressing genes of epithelial-mesenchymal transition (EMT). LG and HG tumors display different patterns of mucin gene expression - epithelial cells of HG express the secreted mucin MUC20 in addition to MUC2 and MUC5B also expressed in LG; a subset of mesothelial cells in LG but not HG express the transmembrane mucin genes MUC1, MUC3A, MUC12 and MUC16. Spatial analysis of tumor AOIs revealed HG compared to LG had increased expression of genes associated with MYC targets, oxidative phosphorylation, anti-tumor immune pathways (IFNα/γ response, intestinal immune network for IGA production), cell cycle pathways (E2F targets, G2M checkpoint) and EMT. LG compared to HG had increased expression of genes associated with inflammation-mediated disease (TNFα signaling via NFKB, inflammatory response), regulation of tumor growth (P53), hypoxia and early cell cycle (estrogen response) and glycosylation pathways. Immune and stromal AOIs did not have significant transcriptomic differences between LG and HG. Conclusion: This study provides novel insights into the biological profile of AT PD by describing TME cell types, immune function, tumor growth and cell cycle pathways. These findings may be used to identify clinically relevant biomarkers and new therapeutic targets. Citation Format: Madeleine C. Strach, Nicole Yeung, Eva Apostolov, Tony Wang, Hui-Ming Lin, Nabila Ansari, Cherry Koh, Joo-Shik Shin, James Kench, Alexander Swarbrick, Lisa Horvath, Kate L. Mahon. Single cell and spatial transcriptomic profile of appendiceal tumour peritoneal disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5480.

Pediatric Intraabdominal Cysts-A Case Series from a Single Tertiary Center Experience.

We aimed to analyze the clinical presentation, imaging, histopathology, and surgical management of pediatric intraabdominal cysts, which are relatively common but diverse lesions that pose diagnostic challenges. We conducted a retrospective analysis of pediatric intraabdominal cysts from 2010 to 2021 in a single tertiary center. We collected data on demographics, symptoms, radiological findings, surgical approaches, and histopathological diagnoses and compared them with the current literature. A total of 36 cases were included. There were 30 females and 6 males, aged 1 to 16 years. Abdominal pain was the most common symptom, followed by tenderness and distention. Diarrhea and vomiting were also reported in some cases. The cysts varied in size, location, and origin and were diagnosed as lymphangioma, mucinous cystadenoma, paratubal cyst, lowgrade mucinous neoplasm, mature cystic teratoma, duplication cyst, mesothelial cyst, pseudocyst, serous cystadenoma, and simple hepatic cyst. The surgical management depended on the type and location of the cysts and involved excision, oophorectomy, appendectomy, or resection. Pediatric intraabdominal cysts are heterogeneous lesions that require timely diagnosis and surgical resection. They may present with various symptoms and complications, depending on their size and location. Radiological and histopathological evaluation is essential for accurate diagnosis and optimal treatment.

Genomic analysis of primary epithelial neoplasms of the seminal vesicle identifies a subset of mucinous cystic tumours driven by KRAS mutations.

Carcinomas of the seminal vesicle are exceedingly rare, with a limited number of cases described in the literature. Reported cases span a relatively wide morphological spectrum, and their genomic features remain unexplored. In this study, we interrogated five primary epithelial neoplasms of the seminal vesicle using a targeted DNA sequencing platform (OncoPanel, 447 genes). The tumours included one adenocarcinoma with intestinal phenotype presenting after external beam radiation (for prostatic adenocarcinoma), one carcinoma with Müllerian-type clear cell phenotype, two mucinous tumours resembling low-grade mucinous neoplasms of the appendix (LAMN) and one mucinous cystadenoma. The post-radiation mucinous adenocarcinoma had genomic findings consistent with bi-allelic inactivation of TP53, as well as multiple copy-number changes with regional and chromosomal arm-level copy-number losses. The Müllerian-type clear cell carcinoma exhibited a complex copy-number profile with numerous regional and arm-level copy-number changes, as well as focal amplification events, including copy-number gain of 8q and amplification of a region within 20q13. Both low-grade mucinous tumours resembling LAMN harboured hot-spot gain-of-function KRAS variants (p.G12V and p.G13D) as the only genomic alteration. No genomic alterations were detected inthe lesion diagnosed as mucinous cystadenoma. Our results suggest that primary low-grade mucinous neoplasms of the seminal vesicle may represent a distinct entity equivalent to appendiceal counterparts, driven by gain-of-function variants of RAS GTPases. The remaining tumours showed genomic features that closely resembled those of neoplasms with comparablephenotypes and/or biological characteristics arising in other sites, suggesting that they could be managed similarly, with special considerations related to their anatomical location.

Appendiceal Mucinous Neoplasms and Inflammatory Bowel Disease: Systematic Review of the Literature.

There is no clear evidence on the prevalence and clinical presentation of appendiceal mucinous neoplasm (AMN) among patients with inflammatory bowel disease (IBD), so a systematic review was performed to investigate the diagnosis, management and treatment of AMN in these patients. PubMed, Medline, Scopus and the Cochrane Library were searched for articles published up to September 2023. Twenty-three studies reporting data about 34 AMN patients were included. UC patients had a median age of 52 years and a median length of disease of 10 years; CD patients had a median age of 40.5 years and a median length of disease of 5 years. A pre-operative diagnosis was achieved in 44% of patients. Most patients were symptomatic (82.6%) and showed moderate-severe disease activity (61%). Surgical procedures were performed: laparoscopic appendectomy, ileocecal resection, right hemicolectomy and colectomy/proctocolectomy. Of the patients, 73.5% were diagnosed with low-grade mucinous neoplasm (LAMN) and nine with adenocarcinoma. Synchronous colorectal dysplasia/carcinoma was present in 23.5% of patients. IBD patients with long-standing disease should be routinely screened, not only for colorectal cancer but also for AMN, during gastro-enterologic follow-up. Laparoscopic appendectomy of unruptured LAMN as well as right hemicolectomy of non-metastatic adenocarcinoma are safe procedures in IBD patients.

Incidental appendiceal neoplasms: Single-centre results.

Histopathological examination of appendectomy specimens may reveal malignancies. Based on these results, either appendectomy is sufficient or sometimes a further treatment protocol can be needed. In this study, malignancy-diagnosed cases on appendectomy specimen were examined. Patients who underwent appendectomy between January 2013 and December 2018 with a pre-diagnosis of acute appendicitis were evaluated retrospectively and those cases with malignancy were included in the study. Patients' age, sex, tumor type, tumor diameter, tumor grade, tumor localization, surgical margin, Ki-67 index, state of lymphovascular invasion, state of peri-neural invasion, and follow-up period duration were recorded. On examination of 2336 appendectomy specimens, 16 patients (0.7%) were found to have neuroendocrine tumors (NET), 11 patients (0.5%) were found to have low-grade mucinous neoplasm (LAMN), and five patients (0.2%) were found to have primary appendix carcinomas. Appendix tumors usually present with acute appendicitis symptoms. Despite re-operation with right hemicolectomy (RHC) being required in the treatment of adenocarcinoma cases, appendectomy provides adequate treatment in most cases with NET and LAMN. With these tumors, which usually have a benign prognosis, it is important to perform the necessary screening in the postoperative period and not to interrupt follow-up.

Determinants of Outcome with Reoperative Surgery for Pseudomyxoma Peritonei in 186 Patients.

To describe the long-term survival and clinical- and treatment-related variables that determine the outcome of repeat cytoreductive surgery (CRS) for mucinous appendiceal neoplasms with peritoneal dissemination. After patients with peritoneal dissemination of an appendiceal mucinous neoplasm have a CRS, disease progression may require secondary cytoreductive surgery (SCRS) and other treatments performed in a timely manner to prolong survival and help preserve an optimal quality of life. The clinical- and treatment-related variables associated with the index CRS and the SCRS were statistically assessed for their impact on survival. One hundred eighty-six of 687 complete CRS patients (27.1%) had SCRS. The median follow-up was 10 years and the median survival was 12 years. There were 95 males (51%) and the median age was 45.0 years. Survival benefit was associated with the index CRS by use of early postoperative intraperitoneal chemotherapy (EPIC) with 5-fluorouracil [Hazard ratio (HR), 0.4; P = 0.0004]. Also, survival of low-grade mucinous appendiceal neoplasms versus mucinous appendiceal adenocarcinoma (HR, 2.8; P < 0.0001) was improved. The interval between index CRS and SCRS was significant at ≤12 months versus 12-36 months versus >36 months (P < 0.0001). Change in peritoneal cancer index and disease distribution as focal or diffuse was significant by univariant and multivariant analyses. If the CRS was complete, the use of EPIC 5-fluorouracil, the interval between the index CRS and the SCRS, the histologic grade of the mucinous neoplasm, and the extent of recurrent disease were prognostic variables that should be used to help select patients for SCRS.

376 Neoplasms of the Appendix- Are They Managed Appropriately?

Abstract Aim Appendix neoplasms are rare. Half are neuroendocrine tumours (NET). Incidence of NET is 0.4 per hundred thousand and of low-grade appendix mucinous neoplasm (LAMN) is 0.2-0.3 per hundred thousand. Most are diagnosed incidentally on appendicectomy specimens. The aim of this study was to ascertain the incidence of appendix neoplasms managed in a tertiary referral centre and to ascertain compliance with international guidelines. Method A prospectively maintained gastrointestinal oncology database was interrogated over a six-year period (July 2016-July 2022). Histologically confirmed primary appendix neoplasms were included. Data collected included patient demographics, clinical presentation, management and follow up (median 38 months). Histopathological staging was according to the AJCC 8th edition. Institutional review board permission was not required. Results Incidence of appendix neoplasm over the study period is 1.3% (16/1259). These included 8 NET, 5 LAMNs, 2 invasive adenocarcinoma and 1 adenocarcinoid. A majority were managed with definitive appendicectomy. One patient underwent right hemicolectomy following discussion at tumour board meeting. Four patients were enrolled on a surveillance programme. A further four with LAMN underwent appendicectomy only and one had appendicectomy and partial caecectomy. Surveillance was not deemed necessary in any of the LAMN cases. Conclusions Incidence of appendix neoplasm in our centre is comparable to that reported in larger series (2%). All cases were discussed at tumour board meeting. Management in all cases was in keeping with current guidelines. While most patients had adequate margin clearance with appendectomy alone, a small number required further surgery and/or surveillance.

Laparoscopic Distal Pancreatico-Splenectomy for Mucinous Cystic Neoplasm of Pancreas

Introduction: Mucinous cystic neoplasms are rare premalignant tumors of the pancreas and account for 1–2% of all pancreatic tumors. Surgical removal before invasive malignancy offers the best long-term outcome.1 Distal pancreatectomy with or without spleen preservation remains the standard procedure. Although an open technique is still the most commonly used approach, laparoscopy is associated with less pain, less blood loss, less morbidity, similar clinical outcomes, and an early return to activities.2,3 This video presents a laparoscopic distal pancreaticosplenectomy (LDPS) performed for a mucinous cystic neoplasm in the body of pancreas. Materials and Methods: A 30-year-old lady presented with a 2-year history of recurrent epigastric pain that had increased in severity over the past 2 months and required admission. Her physical examination was normal. A contrast-enhanced computed tomogram revealed a 3 × 3 cm well-defined cystic lesion in the tail of the pancreas adherent to the splenic vein. An endoscopic ultrasonography with fine needle aspirate revealed a complex cystic mucinous cystic neoplasm measuring 2.8 × 2.5 cm in the body of the pancreas. Owing to its premalignant potential and recurrent symptoms, an LDPS was performed for the mucinous cystic neoplasm of the body of pancreas. Vaccinations covering Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae were administered 2 weeks before surgery. The patient was placed in a French position with ports as shown in the video. Spleen preservation was not attempted because of the splenic vein involvement. The pancreas was divided using a stapler and the vessels were divided using sequential clips. The pancreas was separated from the spleen as it was a nonmalignant lesion and enabled easy removal from the port site without enlarging the incision or morcellation. Results: The operative time was 90 minutes with <10 mL of blood loss. The perioperative course was uneventful, and her diet was resumed on postoperative day 1. The drain was removed on postoperative day 3 after an insignificant drain amylase. The patient was discharged on postoperative day 4. Final histopathology report revealed a low-grade mucinous cystic neoplasm of the pancreas. The patient is asymptomatic at 3 months follow-up. Conclusion: LDPS is a safe and feasible approach for mucinous cystic neoplasms of pancreas. It provides less pain, lower blood loss, and early return to work to the patient while providing similar outcomes. The authors have no commercial associations resulting in conflict of interest with respect to the submitted video. Author(s) have received and archived patient consent for video recording/publication in advance of video recording of procedure. Runtime of video: 9 mins 57 secs This video was presented and awarded third best video presentation at SURGICON 2022 (Annual conference of Association of Surgeons of India—Delhi Chapter) on November 13, 2022.

IPMN-LEARN: A linear support vector machine learning model for predicting low-grade intraductal papillary mucinous neoplasms.

We aimed to build a machine learning tool to help predict low-grade intraductal papillary mucinous neoplasms (IPMNs) in order to avoid unnecessary surgical resection. IPMNs are precursors to pancreatic cancer. Surgical resection remains the only recognized treatment for IPMNs yet carries some risks of morbidity and potential mortality. Existing clinical guidelines are imperfect in distinguishing low-risk cysts from high-risk cysts that warrant resection. We built a linear support vector machine (SVM) learning model using a prospectively maintained surgical database of patients with resected IPMNs. Input variables included 18 demographic, clinical, and imaging characteristics. The outcome variable was the presence of low-grade or high-grade IPMN based on post-operative pathology results. Data were divided into a training/validation set and a testing set at a ratio of 4:1. Receiver operating characteristics analysis was used to assess classification performance. A total of 575 patients with resected IPMNs were identified. Of them, 53.4% had low-grade disease on final pathology. After classifier training and testing, a linear SVM-based model (IPMN-LEARN) was applied on the validation set. It achieved an accuracy of 77.4%, with a positive predictive value of 83%, a specificity of 72%, and a sensitivity of 83% in predicting low-grade disease in patients with IPMN. The model predicted low-grade lesions with an area under the curve of 0.82. A linear SVM learning model can identify low-grade IPMNs with good sensitivity and specificity. It may be used as a complement to existing guidelines to identify patients who could avoid unnecessary surgical resection.

Inframesocolic Approach for Robotic Enucleation of Branch-Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas

BackgroundThe inframesocolic approach to the uncinate process of the pancreas has been rarely described in literature. To the best of our knowledge, no robotic cases have been reported. MethodsThe case of a 74-year-old woman, with a 43-mm branch-duct intraductal papillary mucinous neoplasm with worrisome features within the uncinate process of the pancreas, is described. ResultsAfter diagnostic work-up, due to the uncertain potential of malignancy and the strong motivation of the patient to undergo surgery, we performed a robotic enucleation through an inframesocolic approach. The neoplasm was more than 1 cm from the main pancreatic duct. Final pathological diagnosis revealed a low-grade dysplasia branch-duct intraductal papillary mucinous neoplasm. ConclusionsThe inframesocolic approach could represent an easy way to access the uncinate process of the pancreas, allowing safe limited resection in selected cases such as small branch-duct IPMN or pancreatic neuroendocrine tumors.

Combined appendiceal goblet cell adenocarcinoma and low grade appendiceal mucinous neoplasm: a case report

Appendiceal goblet cell adenocarcinomas (GCA) are rare entities with a distinctive composition of goblet, paneth and neuroendocrine cells. Cases of combined or collision GCAs and other appendiceal tumours exist in the literature, with only a few publications describing combined GCA and low-grade mucinous neoplasm (LAMN). A 73-year-old female underwent a right hemicolectomy following an appendiceal orifice polypectomy showing adenocarcinoma. Histological examination revealed combined GCA and LAMN at the orifice, and LAMN in the remaining appendiceal mucosa. By immunohistochemistry, the GCA showed CK20, synaptophysin and chromogranin reactivity. Grading was performed using the WHO-recommended three-tiered system based on the proportion of low and high-grade morphological features. Current views of GCA and appendiceal neoplasm biology revolve around the unitary hypothesis of neoplasia arising from a pluripotent progenitor cell. This is supported by the observation of varied morphological components at primary and metastatic disease sites, and shared expression of several differentiation markers among appendiceal neoplasms. Genomic studies have shown that appendiceal neoplasms acquire different mutations during tumourigenesis culminating in entities with distinct mutational profiles. Prospective studies into GCA-specific optimal treatment regimens are lacking, and current treatment strategies have been extrapolated from those of appendiceal and colon adenocarcinomas, despite having different pathological molecular signatures.

Preoperative prediction of malignancy and surgical treatment strategy in appendiceal tumors: multicenter review of 51 consecutive cases.

A diagnostic and treatment strategy for appendiceal tumors (ATs) has not been established. We aimed to evaluate our treatment strategy in ATs, including laparoscopic surgery (LS), and to identify preoperative malignancy predictors. A total of 51 patients between 2011 and 2021 were retrospectively reviewed. Data, including tumor markers and imaging findings, were compared between carcinoma and non-carcinoma patients. Validity of planned operation was evaluated based on pathological diagnosis. Twenty-five patients were diagnosed with carcinoma, 13 with low-grade mucinous neoplasm, and 13 with other diseases. Symptoms were more commonly present in carcinoma patients than in non-carcinoma patients (68.0% vs. 23.1%, p = 0.001). Elevated CEA and CA19-9 were more frequently observed in carcinoma patients than in non-carcinoma patients (p < 0.01 and p = 0.04, respectively). Five carcinoma patients had malignancy on biopsy, compared with zero non-carcinoma patients. Significant differences were noted in the percentages of carcinoma and non-carcinoma patients with solid enhanced mass (41.7% vs. 0%, p < 0.001) and tumor wall irregularity (16.7% vs. 0%, p = 0.03) on imaging. Although the sensitivity was not high, the specificity and positive predictive value of these findings were 100%. Forty-two patients (82.4%) underwent LS as minimally invasive exploratory and/or radical operation, of whom 2 were converted to open surgery for invasion of adjacent organ. No patients had intraoperative complications or postoperative mortality. Clinical symptoms, elevated tumor markers, and worrisome features of solid enhanced mass and tumor wall irregularity on imaging can be malignancy predictors. For management of ATs, LS is feasible and useful for diagnosis and treatment.

Histopathological study of lesions of appendix

The human appendix is a supposedly funtionless organ, but can cause morbidity and mortality because it is likely to be infected. Acute Appendicitis being the most common surgical emergency. Appendicectomy specimens from suspected acute appendicitis often appear macroscopically normal but histological analysis reveal a more sinister underlying pathology.A three year study was performed to determine the incidence of various non-neoplastic and neoplastic lesions of appendix. To study the histopathology of various lesions of appendix.It is a retrospective study for a period of three years at Tertiary care hospital. The histopathological reports and clinical details were collected and slides were reviewed and evaluated. Special stains were used wherever required.The study included 1092 cases of lesions of appendix. The commonest lesion was chronic non-specific appendicitis (48.27%) followed by acute appendicitis with (47.80%). Other non neoplastic lesions found were fibrous obliteration of appendix (2.10%), chronic appendicitis with Enterobius vermicularis infestation (0.83), tuberculosis (0.18), xanthogranulomatous appendicitis (0.09%) and amoebic appendicitis (0.09%). Neoplastic lesions seen were low grade mucinous neoplasm (0.18) and serrated adenoma (0.09). Chronic non-specific appendicitis is the commonest appendiceal lesion. The various lesions of appendix clinically present as acute or chronic appendicitis but histology reveals the true nature of the lesion and hence remains the gold standard method.

Clinicopathological features of non-carcinoid malignant epithelial appendix tumors and risk factors for recurrence, single-center experience.

Non-carcinoid appendix epithelial tumors are rare. These tumors include low-grade and high-grade mucinous neoplasm also adenocarcinomas. We aimed to investigate the clinicopathological features, treatment, and risk factors of recurrence. Patients diagnosed between 2008 and 2019 were retrospectively analyzed. Categorical variables were expressed as percentages and compared using the Chi-square test or Fisher's exact tests. Overall survival and Disease-free survival of the groups were calculated by the Kaplan-Meier method, and the log-rank test was used to compare the survival rates. A total of 35 patients were included in the study. Of the patients, 19 (54%) were women and the median diagnosis age of patients was 50.4 years (19-76). As for pathological types, a total of 14 (40%) patients were mucinous adenocarcinoma and 14 (40%) patients were Low-Grade Mucinous Neoplasm (LGMN). Lymph node excision and lymph node involvement were 23 (65%) and 9 (25%) patients respectively. The majority of patients were stage 4 (27, 79%) and 25 (71%) of these patients had peritoneal metastasis. A total of 48.6% patients had been treated with cytoreductive surgery and hyper-thermic intraperitoneal chemotherapy. Median Peritoneal cancer index value was 12 (2-36). The median follow-up time was 20 (1-142) months. Recurrence developed in 12 (34%) of patients. When risk factors for recurrence are considered, there was a statistically significant difference in appendix tumors with high-grade, adenocarcinoma pathology, ones with peritoneal cancer index ≥12 and not having pseudomyxoma peritonei. Median disease-free survival was 18 (13-22, 95% CI) months. Median overall survival could not be reached while the 3-year survival rate was 79%. The risk of recurrence is higher in high-grade appendix tumors, having peritoneal cancer index ≥ 12, not having pseudomyxoma peritonei and adenocarcinoma pathology. High-grade appendix adenocarcinoma patients should be followed closely for recurrence.

A RETROSPECTIVE ANALYSIS OF HISTOPATHOLOGICAL FINDINGS IN APPENDECTOMY SPECIMENS

Background. Retrospectively evaluation of several patients who had undergone appendectomy in our hospital was carried out which aimed to present the efciency of diagnostic tests and demographic data of cases. Available pathological reports were interpreted for the following parameters: age, gender, and pathological diagnosis. In addition, the demographic information and clinicopathologic characteristics of the subjects with unusual histopathologic ndings were assessed in detail, and re-examination of the available resected appendix specimens was done. Methods Inpatient records of the patients who had been operated for acute appendicitis in the hospital associated with Khaja Bandanawaz University – Faculty of medical Sciences; from January 2018 to November 2022, were retrospectively evaluated. Results Subjects were categorized into 2 groups. Cases with histopathologic examination reported as acute appendicitis constituted group-1, and cases with unusual pathologic ndings other than acute appendicitis constituted group-2. The group-2 consisted of low-grade mucinous neoplasms, mucoceles, carcinoid tumor, granulomatous inammation, intraluminal Enterobius vermicularis, and mesenteric cyst. Conclusion Acute appendicitis is a common surgical emergency condition in the department of General Surgery. Most of the resected specimens of appendectomy revealed typical histopathologic ndings, few showed unusual histopathologic ndings. We suggest routine histopathological examination even if the macroscopic appearance of the specimen is normal.

The appendix “mucocoele” misnomer: radiological terminology of “likely appendix mucinous neoplasm” better reflects pathology findings

To review the radiological terminology used to describe dilated mucin-containing appendiceal lesions with correlation to the histopathological diagnosis. Radiology and histopathology reports for all patients with an abnormally dilated appendix referred to a tertiary peritoneal malignancy centre, between January 2021 and December 2021, were reviewed. Overall, 213 patients were included with a median appendiceal diameter of 25.5 mm (range 10-125 mm). Peritoneal disease was present in 109 patients, with the remaining 104 cases demonstrating a dilated appendix only. Local radiology reports were available for 201 cases with the appendix described in 168 cases as appendiceal mucocoele (n=104), appendiceal neoplasm (n=40), appendicitis (n=18), and dilated appendix (n=6). The appendix was not mentioned in 33/201 (15%), either misinterpreted as other pathology (n=15) or not reported (n=18). Peritoneal malignancy histopathology reports were available in 188 cases and reported as low-grade appendix mucinous neoplasm (LAMN, n=144), high-grade appendix mucinous neoplasm (HAMN, n=13), LAMN with foci of HAMN (n=2), LAMN with neuroendocrine tumour (n=2), LAMN with goblet cell adenocarcinoma (n=1), goblet cell adenocarcinoma (n=8), mucinous adenocarcinoma (n=14), non-mucinous adenocarcinoma (n=1), and benign histology (n=3). Only one case of a true inflammatory "mucocoele"/retention cyst was reported. In this cohort of patients, the overwhelming majority of dilated, mucin-filled appendices contained malignant cells and benign mucin-filled appendices were rare. The present authors advocate that the term "likely appendix mucinous neoplasm" should replace "appendix mucocoele" to represent the most likely pathology and facilitate less ambiguous interpretation in management decisions.

Intra-abdominal ectopic bronchogenic cyst with a mucinous neoplasm harboring a GNAS mutation: A case report

BACKGROUNDBronchogenic cysts are congenital cysts caused by abnormal sprouting from the ventral foregut during fetal life. They usually occur in the mediastinum or lung, but there are very rare cases of ectopic bronchogenic cysts that develop in the abdominal cavity. A unique intra-abdominal ectopic bronchogenic cyst with a mucinous neoplasm that was producing carcinoembryonic antigen (CEA), harboring a GNAS mutation, is reported. The present case may contribute to clarifying the mechanism of tumorigenesis and malignant transformation of ectopic bronchogenic cysts.CASE SUMMARYIn 2007, a man in his 50s was incidentally found to have an intra-abdominal cystic mass, 8 cm in diameter. Surgical resection was recommended, but he preferred to remain under observation. In 2020, his serum CEA level increased to 26.7 ng/mL, and abdominal computed tomography showed a 15 cm × 12 cm, multifocal, cystic mass located predominantly on the lesser curvature of the stomach. Since malignancy could not be ruled out, he finally underwent surgical resection. Histologically, the cystic wall was lined by ciliated columnar epithelium, accompanied by bronchial gland-like tissue, bronchial cartilage, and smooth muscle. Part of the cyst consisted of atypical columnar epithelium with an MIB-1 index of 5% and positive for CEA. Moreover, a GNAS mutation (p.R201C) was detected in the atypical epithelium, leading to a diagnosis of an ectopic bronchogenic cyst with a low-grade mucinous neoplasm. The patient is currently undergoing outpatient follow-up without recurrence.CONCLUSIONAn extremely rare case of an abdominal bronchogenic cyst with a low-grade mucinous neoplasm harboring a GNAS mutation was reported.