Visualizing the landscape of appendiceal tumor research after 2010: A bibliometric study.

BACKGROUND: Despite the rarity of appendiceal tumors, research in this field has intensified, resulting in a growing number of studies and published papers. Surprisingly, no comprehensive bibliometric analysis has specifically addressed appendiceal tumors. AIM: To offer a thorough analysis of the current landscape and future trends in appendiceal tumor research. METHODS: In our bibliometric analysis studies, we explored the Web of Science Core Collection database. The bibliographic details of the chosen publications were automatically converted and analyzed using the bibliometric package in the R environment. Additionally, we employed VoSviewer to create cooperation network maps for countries, institutions, and authors, as well as clustering maps for keywords. Furthermore, CiteSpace, another software tool, was utilized to build dual-map overlays of journals and analyze references with citation bursts. RESULTS: Our study included 780 English-language articles published after 2010. The number of related publications and citations has increased in the past decade. The United States leads in this area, but there is a need to improve cooperation and communication among countries and institutions. Co-occurrence analysis also revealed close collaboration among different authors. Annals of Surgical Oncology was the most influential journal in this field. Analysis of references with high co-citations and references with citation bursts, consistent with analysis of keywords and hotspots, indicated that current research primarily centers on the classification and management of appendiceal mucinous neoplasms and consequent pseudomyxoma peritonei. Despite the abundance of clinical studies, a greater number of in-depth basic research studies should be conducted. CONCLUSION: Current research on appendiceal tumors focuses on classification and management of appendiceal mucinous neoplasms and pseudomyxoma peritonei. Enhanced collaboration and basic research are vital for further advancement.

Amyand's Hernia: An Uncommon Encounter of an Appendiceal Presence in an Inguinal Hernia.

Amyand's hernia is a rare variant of inguinal hernia characterized by the presence of the vermiform appendix within the hernia sac. It represents a unique diagnostic and management challenge for surgeons due to its low incidence and varied clinical presentations. Here, we present a case of a 45-year-old man with a one-year history of right inguinoscrotal swelling, diagnosed as a right indirect inguinal hernia. Preoperative imaging revealed the presence of omentum within the hernia sac. Intraoperatively, both the omentum and the vermiform appendix were found within the sac without evidence of inflammation. The patient underwent successful Lichtenstein meshplasty without appendicectomy. This case highlights the importance of considering Amyand's hernia in the differential diagnosis of inguinal hernias and the significance of intraoperative findings in guiding surgical management. Further studies and case reports are needed to enhance our understanding of this rare clinical entity and optimize patient outcomes.

Mucocoele of the appendix.

Introduction: Mucocoele of the appendix occurs in 0.2-0.7% of people in the world without any well-defined clinical symptoms. It occurs when there is an accumulation of mucous in the lumen of the appendix. Case Presentation: We present three cases: a 48-year-old male admitted to the emergency room with a one-day history of right iliac fossa pain. Abdominal examination was suggestive of acute appendicitis. The initial abdominal computerised tomography scan was reported as being unremarkable. At surgery, a firm tumour of the appendix was found, and a limited right hemicolectomy was done. Histopathology confirmed a mucocoele of the appendix with borderline mucinous histology.The second case is a 63-year-old man who presented with a one-year history of abdominal distension and weight loss. Previous abdominal ultrasound was suggestive of liver cirrhosis with significant ascitic fluid. Abdominal magnetic resonance imaging found an appendix mucocoele with infiltration of the omentum and scalloping of the liver surface suggestive of pseudomyxoma peritonei. A percutaneous biopsy of the omental mass confirmed metastatic mucinous adenocarcinoma of the appendix.The third case is a 68-year-old man who, during an annual medical check-up, had an incidental finding of a cystic right iliac fossa mass on ultrasound, confirmed on abdominopelvic computerised tomography scan to be an appendix mucocele. He had laparoscopic appendicectomy. The histopathological diagnosis confirmed a mucinous cystadenoma of the appendix. Conclusion: Preoperative diagnosis of appendiceal mucocoele is difficult and commonly discovered intraoperatively. The prognosis is good for the histologically benign type, but it is poor when malignant or peritoneal lesions are present. Funding: None declared.

Management and Incidence of Enterobius vermicularis Infestation in Appendectomy Specimens: A Cross-Sectional Study of 6359 Appendectomies.

Background: The role of Enterobius vermicularis infestation in the context of appendicitis is largely overlooked, but Enterobius vermicularis is considered an unexpected and significant appendicectomy finding. The aim of this study was to investigate the frequency of Enterobius vermicularis findings in appendectomies and to evaluate the clinical and histopathologic features of patients with Enterobius vermicularis-associated acute appendicitis and those with appendiceal Enterobius vermicularis infestation. Methods: The medical records of all children who underwent an appendectomy in two large pediatric centers in Croatia between 1 January 2009 and 1 January 2024 were retrospectively reviewed. Of 6359 appendectomies, 61 (0.96%) children were diagnosed with Enterobius vermicularis on histopathology and included in further analysis. The groups were compared with regard to demographic characteristics, laboratory values, clinical features and histopathological findings. Results: The incidence of enterobiasis fluctuated slightly in the individual study years, but was constant overall. The median age of all patients was 11 years (IQR 8.5, 13), with females predominating (60.7%). Acute appendicitis was observed in 34% of the appendiceal species. The patients with Enterobius vermicularis infestation, without appendicitis, were younger (9 years (IQR 8, 13) vs. 12 years (IQR 10, 15); p = 0.020), had longer duration of symptoms (36 h (IQR, 12, 48) vs. 24 h (IQR, 12, 36); p = 0.034), lower body temperature (37 °C (IQR 36.8, 37.4) vs. 37.6 °C (IQR, 37, 38.6) p = 0.012), lower Appendicitis Inflammation Response (AIR) score (3 (IQR 2, 5) vs. 7 (IQR 5, 9.5) p < 0.001), lower incidence of rebound tenderness (57.1% vs. 20%; p = 0.003) and less frequent vomiting (12.5% vs. 47.6%; p = 0.004) compared to the patients with Enterobius vermicularis-associated acute appendicitis. Acute inflammatory markers in the laboratory showed significantly higher values in the group of patients with acute appendicitis: C-reactive protein (p = 0.009), White blood cells (p = 0.001) and neutrophils (p < 0.001). Eosinophilia was not found in any of the groups, although eosinophil counts were significantly higher in children who had Enterobius vermicularis infestation than in those with Enterobius vermicularis-related appendicitis (2.5% (IQR 0.9, 4.3) vs. 1.8% (IQR 0.7, 2.1); p = 0.040). Conclusions: Pediatric surgeons should consider Enterobius vermicularis infestation as a differential diagnosis when removing a vermiform appendix. Younger age, longer duration of symptoms, lower body temperature, lower AIR score, lower diameter of the appendix and normal laboratory inflammatory markers could predict Enterobius vermicularis infection in children presenting with right iliac fossa pain and avoid unnecessary appendectomy.

Mucocele of the appendix: case report of a rare disease with changing diagnostic-therapeutic behavior.

Mucinous appendicular neoplasms are a rare and heterogeneous group of tumors, whose treatment may vary based on histologic features and extent. We present a case of low-grade appendiceal mucinous neoplasm mimicking an acute appendicitis scenario. The patient underwent appendectomy along with resection of the caecal fundus. Choosing the correct treatment according to the case by following current guidelines is crucial to avoid under- or overtreatment.

Gastrointestinal Stromal Tumour of the Appendix: A Very Rare Entity.

A 74-year-old man who presented with upper abdominal pain was found to have an incidental appendiceal mass on cross-sectional imaging. He underwent a laparoscopic appendicectomy with histopathological examination confirming a completely resected appendiceal gastrointestinal stromal tumour (GIST). Appendiceal GISTs are rare. Therefore, there is limited evidence to guide risk stratification and management with extrapolation of prognosis from data on GISTs at other sites. This paper highlights the rarity of these tumours and presents another case which correlates well with the existing but limited literature. There is a need to maintain a registry of this rare disease entity with the maintenance of longer-term follow-up data.

Recurrent Ileocolic Intussusception With the Appendix as the Pathologic Lead Point in Children: A Report of Two Cases and Review of Literature.

Ileocolic intussusception is a consideration in young pediatric patients with acute abdominal pain. Meckel's diverticulum is the most common pathologic lead point for intussusception in children and the appendix acting as the lead point is rare. In addition, management guidelines for recurrent ileocolic intussusception (RICI) are lacking. We present two cases of RICI in which the pathological lead point was the appendix. The first patient, a two-year-old with no medical history, had intermittent abdominal pain and non-bloody vomiting for a month. Ultrasound revealed ileocolic intussusception, successfully managed with pneumatic reduction. However, symptoms recurred and a repeat ultrasound showed partial intussusception of the appendix into the cecum. Laparoscopic reduction and appendectomy were then performed. Symptomatic intussusception recurred, and a second laparoscopic reduction with stump appendectomy resolved all symptoms. The second patient, a three-year-old with no medical history, had colicky abdominal pain for 24 hours. Ultrasound revealed ileocolic intussusception that was pneumatically reduced. As pain recurred, laparoscopic reduction and appendectomy were performed, revealing ileocolic intussusception with a dilated appendix as the pathologic lead point. Recurrent ileocolic intussusception (RICI) with the appendix as the lead point is common, but RICI with the appendix as the lead point is rare. These cases demonstrate the role of the appendix as a pathologic lead point, and a review of the literature supports the need for surgical reduction. While enema reduction is the first line for recurrent intussusception, surgical reduction is preferred when a pathological lead point is suspected.

Immunoglobulin G4-related disease mimicking an appendiceal neoplasm: a case report.

Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition characterized by chronic activation of the immune system and a tendency to form tumorous lesions. IgG4-RD is frequently characterized by the presence of tumor-like masses affecting multiple organs and is easily mistaken for a malignant neoplasm. However, IgG4-RD affecting the appendix is extremely rare, with only seven cases reported previously. We report the case of a woman in her early 60s who presented with insidious abdominal pain and radiological findings mimicking appendiceal neoplasms. After diagnosing appendiceal neoplasms, surgery was performed. The patient had a serum IgG4 concentration of <1.35 g/L, which did not satisfy one of the three revised comprehensive diagnostic criteria for IgG4-RD. A pathological examination was conducted, and the patient was diagnosed with appendiceal IgG4-RD. To the best of our knowledge, there have been no previously reported cases of IgG4-RD affecting the appendix in patients with low serum IgG4 concentrations. This report may prove beneficial for the future understanding of IgG4-RD and for the revision of diagnostic and treatment strategies.

Stumped by a Case of Appendicitis After Appendectomy.

Background: Stump appendicitis-a rare, delayed complication of appendectomy-is most commonly managed with surgical exploration and stump appendectomy. Conservative management in the pediatric population is poorly characterized in the literature. Case Report: We report a case of a 10-year-old male who was diagnosed with stump appendicitis and initially treated nonoperatively. He received intravenous antibiotics and supportive therapy while in the hospital, was discharged on a course of oral antibiotics, and remained asymptomatic for the following 9 weeks until he underwent an elective interval stump appendectomy. We also review the literature on this uncommon condition and treatment plan. Conclusion: Considering stump appendicitis in the differential of children with history of appendectomy is imperative. Nonoperative management of stump appendicitis may be successful and beneficial in select pediatric cases compared to the standard surgical management.

Bowel pseudo-obstruction caused by goblet cell adenocarcinoma of the appendix: A case report.

INTRODUCTION: Goblet cell adenocarcinoma of the appendix is a rare diagnosis with features of both adenocarcinomas and carcinoid tumors. Commonly presenting with chronic abdominal pain, appendicitis, or abdominal distention, it can also be incidentally discovered during appendectomies. CASE PRESENTATION: A 50-year-old man with right lower abdominal pain was admitted to our hospital, which is a critical care center. A computed tomography(CT) scan showed ileal narrowing, but endoscopy found no strictures. He was admitted with suspected bowel obstruction and improved with an ileal tube. Laparoscopic surgery revealed a tumor of the appendix. Histologically, he was diagnosed goblet cell adenocarcinoma, suggesting tumor infiltration of nerve fibers impairing peristalsis. DISCUSSION: Goblet cell adenocarcinoma of the appendix has unique histology and a poor prognosis. Treatment typically involves surgery and chemotherapy. This case highlights challenges in preoperative diagnosis, with the tumor causing bowel pseudo-obstruction by invading the intestinal wall and nerve plexus. Extensive infiltration of Auerbach's plexus was observed, consistent with the length of intestinal stenosis. CONCLUSION: This case describes goblet cell adenocarcinoma of the appendix leading to bowel pseudo-obstruction due to ileal end stenosis. It emphasizes the importance of considering this diagnosis in cases of bowel obstruction without an obvious mass.

Appendiceal neoplasms derived from appendiceal tip remnants following appendectomy: a report of two cases.

BACKGROUND: Neoplasms derived from remnant appendix are rarely described, with most cases arising from the appendiceal "stump". Here, we present two surgical cases of appendiceal neoplasms derived from appendiceal "tip" remnants. CASE PRESENTATION: The first patient was a 71-year-old man who had undergone laparoscopic appendectomy for acute appendicitis 12 years prior. During appendectomy, the appendiceal root was ligated, but the appendix was not completely removed due to severe inflammation. At the most recent presentation, computed tomography (CT) was performed to examine choledocholithiasis, which incidentally revealed a cystic lesion of approximately 90 mm adjacent to the cecum. A retrospective review revealed that the cystic lesion had increased in size over time, and laparoscopic ileocecal resection was performed. Pathology revealed no continuity from the appendiceal orifice to the cyst, and a diagnosis of low-grade appendiceal mucinous neoplasm (LAMN) was made from the appendiceal tip remnant. The patient was discharged without complications. The second patient was a 65-year-old man who had undergone surgery for peritonitis due to severe appendicitis 21 years prior. During this operation, the appendix could not be clearly identified due to severe inflammation; consequently, cecal resection was performed. He was referred to our department with a chief complaint of general fatigue and loss of appetite and a cystic lesion of approximately 85 mm close to the cecum that had increased over time. CT showed irregular wall thickening, and malignancy could not be ruled out; therefore, laparoscopic ileocecal resection with D3 lymph node dissection was performed. The pathological diagnosis revealed mucinous adenocarcinoma (TXN0M0) arising from the remnant appendiceal tip. The patient is undergoing follow-up without postoperative adjuvant chemotherapy, with no evidence of pseudomyxoma peritonei or cancer recurrence for 32 months postoperatively. CONCLUSIONS: If appendicitis-associated inflammation is sufficiently severe that accurate identification of the appendix is difficult, it may remain on the apical side of the appendix, even if the root of the appendix is ligated and removed. If the appendectomy is terminated incompletely, it is necessary to check for the presence of a residual appendix postoperatively and provide appropriate follow-up.

The Clinicopathological Significance of Tumor Cell Subtyping in Appendiceal Neuroendocrine Tumors: A Series of 135 Tumors.

Appendiceal neuroendocrine tumors (NETs) are common and often are identified as incidental lesions at the time of appendectomy. The guidelines for management are based on tumor size, degree of invasion, and the Ki67 proliferation index. Most small bowel NETs are composed of serotonin-producing EC-cells, but there are multiple other neuroendocrine cell types. In the rectum, there are L-cell tumors that express peptide YY (PYY), glucagon-like peptides (GLPs), and pancreatic polypeptide (PP); they are thought to have a better prognosis than serotonin-producing tumors. We investigated whether the appendix has distinct neuroendocrine tumor types based on cell type and whether that distinction has clinical significance. We collected 135 appendiceal NETs from the pathology archives of UHN Toronto and UHCMC (Cleveland). We analyzed the expression of biomarkers including CDX2, SATB2, PSAP, serotonin, glucagon (that detects GLPs), PYY, and pancreatic polypeptide (PP) and correlated the results with clinicopathologic parameters. Immunohistochemistry identified three types of appendiceal NETs. There were 75 (56%) classified as EC-cell tumors and 37 (27%) classified as L-cell tumors; the remaining 23 (17%) expressed serotonin and one of the L-cell biomarkers and were classified as mixed. EC-cell tumors were significantly larger with more extensive invasion involving the muscularis propria, subserosa, and mesoappendix compared with L-cell tumors. Mixed tumors were intermediate in all of these parameters. Both EC-cell and mixed tumors had lymphatic and/or vascular invasion while L-cell tumors had none. Unlike EC-cell NETs, L-cell tumors were not associated with lymph node metastasis. Tumor type correlated with pT stage and the only patient with distant metastatic disease in this series had an EC-cell tumor. Our study confirms that appendiceal NETs are not a homogeneous tumor population. There are at least three types of appendiceal NET, including EC-cell, L-cell, and mixed tumors. This information is important for surveillance of patients, as monitoring urinary 5HIAA levels is only appropriate for patients with serotonin-producing tumors, whereas measurement of GLPs and/or PP is more appropriate for patients with L-cell tumors. Our data also show that tumor type is of significance with EC-cell tumors exhibiting the most aggressive behavior.

Factors Affecting Survival Outcomes in Neuroendocrine Tumor of the Appendix over the Past Two Decades.

BACKGROUND: Appendiceal neuroendocrine tumors (NETs) rank as the third most frequent neoplasm affecting the appendix, originating from enterochromaffin cells. This study aims to evaluate the influence of various prognostic factors on the mortality rates of patients diagnosed with NETs of the appendix. METHODS: Conducted retrospectively, the study involved 3346 patients, utilizing data sourced from the Surveillance, Epidemiology, and End Results (SEER) database. Our analysis centered on investigating demographic characteristics, clinical features, overall mortality (OM), and cancer-specific mortality (CSM) among the cohort. Variables showing a p-value < 0.1 in the univariate Cox regression were incorporated into the multivariate Cox regression analysis. A Hazard Ratio (HR) > 1 indicated an unfavorable prognosis. RESULTS: In the multivariate analysis, higher OM and CSM were observed in males, older age groups, tumors with distant metastasis, poorly differentiated tumors, and those who underwent chemotherapy. Non-Hispanic Black individuals showed elevated mortality rates. CONCLUSION: Delayed diagnosis may contribute to the increased mortality in this community. Improved access to healthcare and treatment is crucial for addressing these disparities. Larger prospective studies are needed to pinpoint the underlying causes of elevated mortality in non-Hispanic Black populations, and randomized controlled trials (RCTs) are warranted to evaluate therapies for advanced-stage appendix NETs.

Conspiring simplification strategies of [Obstruent+Liquid] clusters in a case study of child Greek: emergence of the marked.

This paper addresses the idiosyncratic cluster simplification patterns observed in a child with disordered phonological development, who is acquiring Greek. The child has mastered word-internal and word-final codas and clusters of reversed sonority. However, the child does not realise the target well-formed tautosyllabic [Obstruent+Liquid] clusters with rising sonority. The child's system requires a single onset with maximum sonority dispersion between the onset and the syllable nucleus. As a result, cluster simplification occurs, via reduction to the less sonorous Obstruent - the most prevalent reduction pattern cross-linguistically. However, at the same time, the grammar requires faithful realisation of the target segment number. This requirement is fulfiled through two distinct conspiring metathesis patterns, distributed complementarily, resulting in the realisation of marked structures. The patterns depend on the position of the cluster within the target word. In word internal position, a compensatory metathesis of the Liquid takes place in the preceding syllable coda. In word initial position, the Manner of Articulation of the metathesised Liquid is delinked, while its Coronal Place of Articulation is faithfully preserved, and is realised by default as a Coronal Sibilant [s]. The latter Sibilant is attached as an appendix to the syllable node at the word left-edge. We argue that, in the grammar of this child, there is a-synchronisation between the development of the prosodic word layer and the development of syllable layer. Specifically, a-synchronisation is evident in the development of the (branching) onset syllabic subconstituent.

Finding Waldo: Sonographic systematic approach to localize the appendix in children.

OBJECTIVES: To describe a systematic scanning approach using anatomical landmarks followed by an assessment of radiology trainees' ability to identify the normal appendix in healthy children. METHODS: Uncontrolled pre and post study assessing radiology residents' sonographic skills in detecting the normal appendix in healthy children. Initial questionnaire for the trainees' demographics, perceptions and experiences in detecting the appendix with ultrasound in children followed by a precourse test on healthy volunteers. Hands-on training was conducted by describing a systematic sonographic approach to identify the appendix using anatomical landmarks, and then a postcourse test was carried out. The primary outcome was unprompted ability to identify the appendix. Subjective self-scoring of confidence was also recorded. RESULTS: A three-hour hands-on workshop was conducted. Sixteen radiology trainees participated and were randomly distributed to four stations, each with different ultrasound machines and healthy volunteers. Fifteen had a precourse assessment, and 12 completed the postcourse assessment. Before the course, 3/15 (20%) identified the appendix, while 10/12 (83%) identified the appendix afterward. After the course, participants perceived finding the appendix easier than before. There was no statistically significant difference in the participants' perceived confidence in detecting the appendix. CONCLUSIONS: With the described scanning technique, most of the participants were able to identify the normal appendix after receiving short hands-on training. This highlights the importance of targeted training of radiology trainees and nonradiologists.

A Case Report of Appendicitis Causing Cecal Volvulus: A Rare Occurrence.

This case report presents a fascinating scenario involving a 60-year-old female who was diagnosed with cecal volvulus secondary to appendicitis. The patient's initial presentation included a three-day history of periumbilical pain accompanied by reduced oral intake and an inability to pass stool. Through a systematic approach involving detailed history-taking, comprehensive physical examinations, and pertinent imaging studies, a precise diagnosis of cecal volvulus induced by appendicitis was established. Subsequently, the patient underwent a timely operation, leading to a successful resolution of her condition and a remarkably swift recovery post-surgery. This unique case prompts a deeper exploration into the incidence and management of this rare phenomenon, where the seemingly unrelated condition of appendicitis precipitated a cecal volvulus. Given the unusual nature of this presentation, it underscores the importance of considering atypical etiologies in patients presenting with signs and symptoms of bowel obstruction. This discussion aims to shed light on the diagnostic challenges, treatment strategies, and outcomes associated with this intriguing interplay of pathologies, offering valuable insights for clinicians encountering similar cases in their practice.

Nodular image in the appendix observed on ultrasound: endometriosis or neuroendocrine neoplasia?

Objective: To evaluate the association between clinical and imaging with surgical and pathological findings in patients with suspected neuroendocrine tumor of appendix and/or appendix endometriosis. Methods: Retrospective descriptive study conducted at the Teaching and Research Institute of Hospital Israelita Albert Einstein, in which medical records and databases of patients with suspected neuroendocrine tumor of appendix and/or endometriosis of appendix were analyzed by imaging. Results: Twenty-eight patients were included, all of which had some type of appendix alteration on the ultrasound examination. The pathological outcome of the appendix found 25 (89.3%) lesions compatible with endometriosis and three (10.7%) neuroendocrine tumors. The clinical findings of imaging and surgery were compared with the result of pathological anatomy by means of relative frequency. Conclusion: It was possible to observe a higher prevalence of appendix endometriosis when the patient presented more intense pain symptoms. The image observed on ultrasound obtained a high positive predictive value for appendicular endometriosis.

Appendiceal Metastasis of Breast Cancer: A Case Report and a Literature Review.

Appendiceal metastases of breast cancer (BC) are very rare, and there are few reports of resection. Asymptomatic appendiceal enlargement is often suspected to be a primary appendiceal tumor, making it difficult to suspect metastatic tumors, especially metastases from BC. On the other hand, advances in drug therapy, including hormonal therapy for BC, have prolonged survival, and there is a possibility of encountering metastatic cases that have rarely been seen before. We herein present a case in which an enlarged appendix, identified during hormonal therapy for advanced BC, was laparoscopically removed and diagnosed as BC metastasis. A 53-year-old woman had been diagnosed with invasive ductal carcinoma (IDC) based on a breast biopsy, and the appendiceal specimen was diagnosed as invasive lobular carcinoma (ILC). We herein report this unique case and provide a detailed review of 13 previous reports.