Clinical features, treatments and prognosis of appendiceal bleeding: a case series study.

BACKGROUND: Appendiceal bleeding is a rare cause of lower gastrointestinal bleeding, could be overlooked and diagnosed as obscure gastrointestinal bleeding. Due to limited real-world cases, the optimized management of appendiceal bleeding is unclear. We here shared our experiences in the past 20 years. METHODS: A retrospective study was conducted at West China Hospital of Sichuan University. We reviewed data of 28,175 colonoscopies from 43,095 gastrointestinal bleeding patients between June 2003 and June 2023. Six patients diagnosed as appendiceal bleeding were included. Data including symptoms, laboratory tests, imaging results, endoscopic findings, treatment and prognosis were collected and analyzed. RESULTS: Appendiceal bleeding accounts for 0.014% in gastrointestinal bleeding patients. Of the six patients, five were male, with a mean age of 48.5 years. Hematochezia was the most common symptom. The etiology included appendiceal angiodysplasia, appendicitis and appendectomy associated bleeding. Hemostasis was achieved by appendectomy, endoscopic therapy or medication according to different cases. One patient did not receive any treatment because of self-limiting bleeding. CONCLUSIONS: The diagnosis of appendiceal bleeding is challenging, repeated flushing during endoscopy is helpful. Appendectomy is the priority option for treatment as well as the etiology clarification, therapeutic endoscopy and medication could be considered case by case.

Management of mucocele of the appendix with peritoneal dissemination in pregnant women: a case report and literature review.

BACKGROUND: This is the first case report of a patient with a twin pregnancy who developed appendiceal mucocele (AM) with peritoneal dissemination in the context of endometriosis and ovarian hyperstimulation. A review of the literature on AM during pregnancy, with a focus on management, is provided as well. CASE PRESENTATION: A 36-year-old woman was admitted to the emergency department for abdominal pain in the right iliac fossa at 17 weeks of amenorrhoea (WA). She was pregnant with twins, achieved by in vitro fertilisation (IVF) and complicated by ovarian hyperstimulation syndrome. Abdominal ultrasonography indicated a diagnosis of uncomplicated acute appendicitis. However, the histopathological findings revealed low-grade appendicular mucinous neoplasia (LAMN) with peritoneal dissemination of acellular mucin. Maximal cytoreductive surgery with hyperthermic intraperitoneal mitomycin chemotherapy was performed post-partum. CONCLUSIONS: Specialised management is required for AM during pregnancy and must take into account the progress of the pregnancy, the histology of the AM and the risk of perforation.

[Adult Intussusception Associated with a Low-Grade Appendiceal Mucinous Neoplasm-A Case Report].

A 52-year-old woman patient, who presented with lower abdominal pain, was suspected of having colonic intussusception. An enhanced CT examination indicated that the end of the small intestine or appendix tumor had invaginated into the transverse colon. The CT revealed no evidence of intestinal ischemia, the emergency operation was performed on the following day. After relieving a colonic intussusception, a mass of the appendix was found and we performed laparoscope-assisted ileocolic resection and D3 dissection because of a strong possibility of carcinoma. The patient was discharged 8 days after the surgery and showed no evidence of recurrence for 6 months after the surgery. In postoperative histopathological examination, appendix tumor was diagnosed as a low-grade appendiceal mucinous neoplasm(LAMN). Adult intussusception is a rare disease and most of the cases are caused by malignant lesions, and a treatment strategy for LAMN has not yet been established. We report this case , as there are very few reported cases of adult intussusception caused by LAMN, with a review of the relevant literature.

[Goblet Cell Carcinoid of the Appendix with Complicated Appendicitis-A Case Report].

A 50-year-old male was referred to our hospital for the further evaluation and treatment of abdominal pain. He was diagnosed with complicated appendicitis using computed tomography. After conservative treatment, he underwent an interval appendectomy. A histopathological examination revealed a goblet cell carcinoid(GCC)of the appendix with subserosal invasion. He underwent laparoscopic ileocecal resection with D3 lymph node dissection. Histopathological findings showed neither residual tumor nor lymph node metastasis. The patients is currently followed as an outpatient without recurrence. Here we report our experience with GCC, a rare disease.

[A Case of Appendiceal Metastasis from Hilar Cholangiocarcinoma with Acute Perforated Appendicitis and Cholecystitis].

An 88-year-old woman had been diagnosed with hilar cholangiocarcinoma for 3 years since she received metallic stents for malignant biliary obstruction, and observed without any aggressive medical treatment. She was admitted to our hospital for further investigation of her abdominal pain. Abdominal CT showed an enlarged gallbladder, fluid collection in the right paracolic gutter, and swollen appendix. Laboratory tests showed high-grade inflammation. She was diagnosed with acute perforated appendicitis with acute cholecystitis. Laparoscopic cholecystectomy and appendectomy were performed. Perforation was confirmed intraoperatively in the appendix wall and accumulation of pus was found in the right paracolic gutter. There were no macroscopic findings of metastasis and peritoneal dissemination. Microscopic examination of the resected appendix showed adenocarcinoma cells positive for CK7 and negative for CK20 and CDX2, and were predominantly infiltrated from the muscular layer to the serosa of the appendix wall, with a diagnosis of appendiceal metastasis from hilar cholangiocarcinoma. Metastatic appendiceal carcinoma is rare, and appendiceal metastasis from hilar cholangiocarcinoma is extremely rare. Herein, we report a rare case of metastatic appendiceal carcinoma from hilar bile duct cancer with acute perforated appendicitis and cholecystitis along with findings of previous literature.

The association between appendicitis severity and patient age with appendiceal neoplasm histology-a population-based study.

PURPOSE: Recent studies have reported alarming appendiceal tumor rates associated with complicated acute appendicitis, especially in patients presenting with a periappendicular abscess. However, the data on histology of appendiceal tumors among acute appendicitis patients is limited, especially in patient cohorts differentiating between uncomplicated and complicated acute appendicitis. We have previously reported the association of increased appendiceal tumor prevalence with complicated acute appendicitis in this population-based study. The objective of this secondary analysis was to evaluate the association of both appendicitis severity and patient age with appendiceal tumor histology. METHODS: This nationwide population-based registry study (The Finnish Cancer Registry) was conducted from 2007 to 2013. All appendiceal tumors (n = 840) and available medical reports (n = 504) of these patients at eight study hospitals were previously evaluated, identifying altogether 250 patients with both acute appendicitis and appendiceal tumor. RESULTS: The severity of acute appendicitis was significantly associated with more malignant tumor histology. The risk of adenocarcinoma or pseudomyxoma was significantly higher among patients with periappendicular abscess (OR 15.05, CI 95% 6.98-32.49, p < 0.001) and patients presenting with perforated acute appendicitis (OR 4.09, CI 95% 1.69-9.90, p = 0.0018) compared to patients with uncomplicated acute appendicitis. Similarly, patient age over 40 years was significantly associated with the risk of adenocarcinoma and pseudomyxoma (OR 26.46, Cl 95% 7.95-88.09, p < 0.001). Patient sex was not associated with a more malignant appendiceal tumor histology (p = 0.67). CONCLUSION: More malignant appendiceal tumor histology of adenocarcinoma or pseudomyxoma was significantly associated with patient age over 40 years and complicated acute appendicitis, especially periappendicular abscess.

Comparison of the risk of appendiceal tumors in uncomplicated and complicated appendicitis.

BACKGROUND: Interval appendectomy or non-operative management is commonly performed for complicated appendicitis in adult patients. However, these treatments are still controversial because the incidence rate of appendiceal tumors recognized after interval appendectomy is reportedly higher than that after emergency appendectomy. Thus, this study aimed to compare the appendiceal tumor rates between uncomplicated and complicated appendicitis. METHODS: This study was a retrospective review of patients with appendicitis who underwent surgical removal at a single institution over 7.5 years. The primary objective was the comparison of the incidence rate of appendiceal tumors using propensity score matching, and the secondary objective was the same comparison among older patients, defined as patients aged ≥ 60 years. RESULTS: A total of 1277 patients were included. Of these patients, 297 (23.3%) were preoperatively diagnosed with complicated appendicitis. Moreover, 22 (1.7%) patients, including 14 cases of complicated appendicitis and 8 cases of uncomplicated appendicitis, were diagnosed with appendiceal tumors based on pathological examination. No significant difference was found in the incidence rate of appendiceal tumors between the two groups after matching for patients' background, including age, sex, and history of appendicitis by propensity score matching (P = 0.073). However, among patients aged ≥ 60 years, the incidence of appendiceal tumors was significantly higher in complicated than in uncomplicated appendicitis (P = 0.006). CONCLUSIONS: Although the overall risk of appendiceal tumors did not differ between complicated and uncomplicated appendicitis when analyzed by the propensity score matching, in older patients aged ≥ 60 years, the risk increased among those with complicated appendicitis. Therefore, although the incidence is low, complicated appendicitis, particularly, among older patients, should be examined carefully and be performed IA when unusual findings exist.

Surgical indication for right hemicolectomy in goblet cell adenocarcinoma of the appendix.

We have read with interest the article by Pérez Montiel CA et al., in which goblet cell adenocarcinoma (GCA) is described as a cause of acute appendicitis. Although the article is brilliant in terms of histopathological description of the appendiceal GCA, the surgical indication for right hemicolectomy should be analyzed in depth due to the great controversy that exists in the scientific literature.

Acute lower gastrointestinal bleeding due to low-grade mucinous neoplasm of appendix.

INTRODUCTION: Lower gastrointestinal tract (GIT) bleeding originating from the appendix is rare and may be difficult to diagnose. PATIENTS AND METHODS: In this case report, we present an 88-year-old male patient who was admitted with hematochezia due to appendiceal bleeding. A colonoscopy revealed bleeding in the appendix orifice so an appendectomy was performed, and bleeding did not recur in the postoperative period. RESULTS: The results of the microscopic examination showed low-grade mucinous neoplasm (LGMN) of the appendix. CONCLUSION: It should be kept in mind that bleeding may originate from the appendix in patients presenting with GIT bleeding. Our patient is the first to present with an acute lower GIT bleed who was diagnosed as having LGMN in the appendectomy specimen.

Appendiceal goblet-cell adenocarcinoma: a rare cause of acute appendicitis.

We present the case of a 70-year-old male who consulted for abdominal pain, vomiting, fever, and signs of peritoneal irritation. Histopathology showed goblet-like cells organized in nests, without tubules, with transmural infiltration. Immunohistochemistry was positive for synaptophysin and chromogranin, and a grade-3 goblet-cell adenocarcinoma (GCA) was diagnosed.

[Two Cases of Synchronous Double Primary Prostate Cancer Accompanying Bone Metastasis and Colon Cancer].

We report two cases of synchronous double primary cancers, which were composed of prostate cancer accompanied by bone metastasis and colon cancer, within only five months of each other. The first was a 77-year-old man whose ECOG PS was 0. He was referred to our hospital in March 2020 because abdominal CT scan, which was performed at a clinic for the purpose of close examination of poor control of diabetes, showed wall thickening of the sigmoid colon. A further examination revealed prostate cancer accompanied by metastatic bone cancer and sigmoid colon cancer. Laparoscopic sigmoid colectomy was performed in April. Currently, six months after the surgery, both the prostate cancer and its accompanying metastatic bone cancer are well controlled by hormonal therapy. The second case was an 86-year-old man with an ECOG PS of 3 who was brought to our hospital by ambulance in August, 2020 because of fever and abdominal pain. A close examination revealed cecal cancer accompanying acute appendicitis. Prostate cancer accompanied by metastatic bone cancer was also diagnosed. Laparoscopic ileocecal resection was performed in the same month, but, unfortunately, the patient had repeated aspiration pneumonia and he finally passed away 43 days after surgery. We discuss the treatment strategy for colorectal cancer with synchronous or metachronous prostate cancer, which has been increasing in recent years, and include epidemiological considerations.

[Analysis of correlation factors and risk prediction for acute appendicitis associated with appendiceal neoplasms].

Objective: To examine the correlation factors of acute appendicitis associated with appendiceal neoplasms. Methods: Consecutive 712 patients with acute appendicitis who treated at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from January 2002 to December 2016 were analyzed retrospectively. There were 314 females and 398 males, aging (42.5±16.2) years (range: 14 to 94 years). Among the 712 cases, 36 patients were diagnosed with acute appendicitis associated with appendiceal neoplasms, the other 676 patients had no appendiceal neoplasm. The patients' clinical baseline characteristics and clinical parameters were compared between the two groups. The correlation factors of acute appendicitis associated with appendiceal neoplasms were evaluated by using the univariate (χ2 test or t test) and multivariate Logistic regression analysis. The area under curve of receiver operating characteristic curves was utilized to evaluate the discriminatory power of the predictive models. Results: According to the univariate analysis, gender, age, body mass index, the duration of chronic right low abdominal pains≥3 months, the frequency of recurrently acute right lower abdominal pain≥2, the frequency of acute right lower abdominal pain, past history of diabetes, hypertension or coronary heart disease, the level of neutrophils and leukocytes preoperatively, stercolith and periappendiceal effusion, and modified Alvarado score were positively correlated with appendiceal neoplasms (all P<0.05). Then four variables were incorporated into the model eventually by multivariate Logistic regression analysis, which were as follows: age (increased per decade) (OR=2.23, 95%CI: 1.68 to 2.95, P<0.01), gender (female) (OR=4.21, 95%CI: 1.74 to 10.19, P=0.001), the duration of chronic right low abdominal pains (more than 3 months) (OR=2.53, 95%CI: 1.01 to 3.37, P=0.048), and modified Alvarado score (decreased per 1 score) (OR=2.54, 95%CI: 1.87 to 3.34, P<0.01). The area of curve was 0.93 (95%CI: 0.88 to 0.97), which indicated that the model exhibits an excellent ability to discriminate between appendiceal neoplasms and acute appendicitis. Conclusions: The older age, female, the duration of chronic right low abdominal pains, and lower modified Alvarado score are independent correlation factors for acute appendicitis associated with appendiceal neoplasms. Clinicians should be alert for the above clinical characteristics and choose optimal treatment for acute appendicitis associated with appendiceal neoplasms.

[A Case of Appendiceal Intussusception Induced by Early Appendiceal Carcinoma].

Appendiceal intussusception is an uncommon pathologic condition. We report herein a case of appendiceal intussusception induced by appendiceal carcinoma. A 76-year-old woman was admitted to hospital because of epigastric pain. CT scan showed multiple concentric ring sign in ascending colon and enhanced tumor in transverse colon. Colonoscopy showed invagination of polypoid lesion which was pushed back to cecum endoscopically. Laparoscopy-assisted ileocecal resection with regional lymph node dissection was performed for cecal cancer. During surgery, the appendix was found to be inverted completely into the cecum. The tumor was 70×35 mm in size in the cecal cavity, and the appendix had completely invaginated into the cecum at its base. Histopathologic examination revealed early appendiceal carcinoma. The patient is healthy without recurrence.

Mode of Presentation in 1070 Patients With Perforated Epithelial Appendiceal Tumors, Predominantly with Pseudomyxoma Peritonei.

BACKGROUND: Perforated epithelial appendiceal tumors are uncommon and can give rise to pseudomyxoma peritonei. Pseudomyxoma peritonei is rare, almost always of appendiceal origin, and presents in various ways relevant to abdominal surgeons. OBJECTIVE: The aim of this study was to report the mode of presentation of pseudomyxoma peritonei of appendiceal origin in patients treated in a high-volume UK peritoneal malignancy center. DESIGN: A retrospective observational study was conducted. SETTINGS: This was a single-center study. PATIENTS: Retrospective analysis of a prospective database of consecutive patients undergoing surgery between March 1994 and December 2016 was performed. MAIN OUTCOME MEASURES: Mode of presentation was classified into 7 categories: "histological diagnosis at abdominal surgery for presumed appendicitis," "probable pseudomyxoma peritonei" based on abnormality on cross-sectional imaging (± image-guided biopsy)," "abnormal imaging (other cause suspected) and operative finding of pseudomyxoma peritonei," "diagnostic laparoscopy," "ovarian mass," "new-onset hernia," and "miscellaneous." RESULTS: Overall, 1070 patients underwent surgery (female 61%, male 39%); median age was 57. The mode of presentation was abnormality on cross-sectional imaging in 324 of 1070 patients (30.3%), histological diagnosis at emergency surgery for presumed appendicitis in 203 of 1070 patients (19%), and abnormal imaging with eventual pseudomyxoma peritonei diagnosis in 180 of 1070 patients (16.8%); 124 of 651 women (19.2%) presented with an ovarian mass. New-onset hernia was the presenting feature in 9.9%; 83 of 1070 patients (7.7%) were diagnosed at diagnostic laparoscopy, and 32 of 1070 patients (3%) were described as "miscellaneous." Overall, 775 of 1070 patients (72.4%) had complete cytoreductive surgery with 10-year survival of 63.5%. LIMITATIONS: Results are limited by the retrospective nature of the study, radiological improvements over the study period, and the number of patients who had overlapping features at presentation. CONCLUSION: Perforated appendiceal tumors present in various ways but predominantly at cross-sectional imaging or coincidentally at laparoscopy or laparotomy. All abdominal surgeons will occasionally encounter cases, often unexpectedly, and recognition and referral to a specialized unit results in excellent outcomes in most cases. See Video Abstract at http://links.lww.com/DCR/B256. MODO DE PRESENTACIÓN EN 1070 PACIENTES CON TUMORES EPITELIALES APENDICULARES PERFORADOS, PREDOMINANTEMENTE CON PSEUDOMIXOMA PERITONEAL: Los tumores epiteliales apendiculares perforados son poco frecuentes y pueden dar lugar a Pseudomyxoma peritonei. El pseudomixoma peritoneal es raro, casi siempre de origen apendicular, y se presenta de diversas formas relevantes para los cirujanos abdominales.El objetivo fue informar el modo de presentación del Pseudomixoma peritoneal de origen apendicular en pacientes tratados en un centro de malignidad peritoneal de alto volumen en el Reino Unido.Se realizó un estudio observacional retrospectivo.Este fue un estudio de centro único.Análisis retrospectivo de una base de datos prospectiva de pacientes consecutivos sometidos a cirugía entre marzo de 1994 y diciembre de 2016.El modo de presentación se clasificó en 7 categorías: "diagnóstico histológico en la cirugía abdominal por presunta apendicitis", "probable Pseudomixoma peritoneal" basado en la anormalidad en la imagen de corte transversal (biopsia guiada por imagen +/-), "imagen anormal (se sospecha otra causa) y hallazgo quirúrgico de Pseudomixoma peritoneal", "laparoscopia diagnostica", "masa ovarica", "hernia de reciente aparicion" y "varios".En total, 1070 pacientes fueron operados (mujeres 61%, hombres 39%); edad media 57. El modo de presentación fue anormalidad en la imágen transversal en 324/1070 (30.3%), el diagnóstico histológico en cirugía de emergencia por presunta apendicitis en 203/1070 (19%), la imágen anormal con eventual diagnóstico de Pseudomixoma peritoneal en 180 / 1070 (16.8%), 124/651 (19.2%) las mujeres presentaron una masa ovárica. La hernia de reciente aparición fue la característica de presentación en 9.9%, 83/1070 (7.7%) fueron diagnosticados por laparoscopia diagnóstica y 32/1070 (3%) "misceláneos". En general, 775/1070 (72,4%) se sometió a cirugía citorreductora completa con una supervivencia a 10 años del 63,5%.Una deficiencia es que los resultados están limitados por la naturaleza retrospectiva del estudio, las mejoras radiológicas a lo largo del período de estudio, y varios pacientes tenían características superpuestas en la presentación.Los tumores apendiculares perforados se presentan de varias maneras, pero predominantemente en imágenes transversales o casualmente en laparoscopia o laparotomía. Todos los cirujanos abdominales encontrarán ocasionalmente con casos, a menudo inesperados, y el reconocimiento y la derivación a una unidad especializada da lugar a excelentes resultados en la mayoría de los casos. Consulte Video Resumen en http://links.lww.com/DCR/B256.).

A goblet cell carcinoma of the appendix presenting as an acute appendicitis: a case report.

Background: A goblet cell carcinoma of the appendix is a rare neoplasm with histological features of both adenocarcinomas and carcinoid tumours. It has a more aggressive behaviour in comparison to the more common classic neuroendocrine appendiceal tumours. Clinical presentation is variable and a significant proportion of patients present with an acute appendicitis. The aggressive evolution of these tumours makes the management more challenging.Case report: We report the case of a 43-year-old man with acute right iliac fossa pain who was initially diagnosed with an acute appendicitis. Histological analysis of the resected appendix demonstrated the presence of a goblet cell carcinoma with perineural and lymphovascular invasion. No distant metastasis was present. A right hemicolectomy was performed and adjuvant chemotherapy was administered.Conclusion: Goblet cell carcinomas is a distinct entity which should be delineated from the classical appendiceal carcinoids. Its clinical evolution obliges a more aggressive therapeutic strategy.

[More than Four-Year Survival of Appendiceal Adenocarcinoma Due to Goblet Cell Carcinoid and Manifesting as an Abdominal Tumor and Hydronephrosis].

An 89-year-old woman with complete blindness presented with a right lower abdominal tumor and weight loss. The CT scan showed a huge mass approximately 9 cm in diameter in the ileocecum, invading the right urinary tract and right iliac artery and vein. Findings of the TCS biopsy led to the suspicion of ileocecal carcinoid. Another punch biopsy specimen acquired under general anesthesia indicated mucinous cell carcinoma. When she suffered from right leg pain approximately 3 months later, we provided radiation therapy(50 Gy)because of intolerance to UFT. Consequently, pain disappeared, and the tumor size decreased significantly. We administered TS-1 but discontinued it because of intolerance. Further, 2.8 years after the first medical examination, the tumor recurred, and she developed ileus. We performed ileocolectomy, and pathological findings indicated that the adenocarcinoma in the appendix had progressed from goblet cell carcinoid(sig, si[right ovary], ly1b, v1a, n0). Four years after the first medical examination, CEA had elevated rapidly, and lung metastases were found. She died approximately 4.2 years after the first medical examination. The last measured CEA level had been 596.7 ng/mL. Starting from the lowest level at the first examination, the CEA level had slowly elevated until before the operation and rapidly elevated postoperatively. Immunopathological findings showed that the operated specimen stained diffusely for CEA, without any mucinous component. We suspected that radiation therapy modified goblet cell carcinoid to adenocarcinoma.

Multifocal Appendiceal Carcinoid Tumor in an Adolescent: A Case Report and Review of the Literature.

Appendiceal carcinoid tumors in children and adolescents are rare. This report describes a case of a multifocal appendiceal carcinoid tumor identified incidentally following appendectomy in an adolescent. In this report, we describe the staging process and surgical management for focal and locally invasive appendiceal carcinoid tumors and highlight the rarity of multifocality in this location. The diagnostic and pathologic challenges for this case are presented.

Pseudomyxoma peritonei induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer: a case report and literature review.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a disease involving the peritoneum characterized by the production of large quantities of mucinous ascites. PMP has a low incidence, is difficult to diagnose, and has a guarded prognosis. PMP induced by low-grade appendiceal mucinous neoplasm is extremely rare, and PMP accompanied by rectal cancer is even rarer. CASE PRESENTATION: We present a unique case of a 70-year-old male with PMP induced by low-grade appendiceal mucinous neoplasm accompanied by rectal cancer. The patient's clinical, surgical, and histologic data were reviewed. The patient had persistent distended abdominal pain without radiating lower back pain, abdominal distension for 1 month, and no exhaustion or defecation for 4 days. A transabdominal ultrasound-guided biopsy was performed on the first day. The patient received an emergency exploratory laparotomy because of increased abdominal pressure. We performed cytoreductive surgery, enterolysis, intestinal decompression, special tumour treatment and radical resection of rectal carcinoma. The postoperative course was uneventful. The postoperative histological diagnoses were PMP, low-grade appendiceal mucinous neoplasm and rectal medium differentiated adenocarcinoma. At the 1-year follow-up visit, no tumour recurrence was observed by computed tomography (CT). We also performed a literature review. CONCLUSIONS: We should be aware that PMP can rarely be accompanied by rectal cancer, which represents an easily missed diagnosis and increases the difficulty of diagnosis and treatment. Additionally, there are some typical characteristics of PMP with respect to diagnosis and treatment.

[A Case of Strangulating Intestinal Obstruction Caused by Coiling of Low-Grade Appendiceal Mucinous Neoplasm to Terminal Ileum].

The patient was a 67-year-old female without a history of surgery. She presented with an abdominal pain and vomiting, and was rushed to our hospital. The abdominal pain was severe, but no peritoneal irritation sign was observed. Abdominal CT scan revealed a strangulating intestinal obstruction and accumulation of ascitic fluid. Emergency surgery was performed for diagnosis and treatment. The intraoperative finding showed serous ascitic fluid and strangulating intestinal obstruction caused by appendiceal tumor coiling around the terminal ileum, which had become ischemic with thinning of its wall. Ileocecal resection with removal of lymph nodes(D3)was performed. The postoperative course was uneventful, and the patient was discharged 13 days after the surgery. Pathological examination of the appendiceal tumor revealed a low-grade appendiceal mucinous neoplasm(LAMN)with no metastasis to the lymph nodes. We had a rare case of strangulating intestinal obstruction caused by coiling of LAMN to the terminal ileum.

[A Case of Appendiceal Neuroendocrine Tumor Diagnosed after Appendectomy].

A 25-year-old woman visited our hospital with a complaint of right lower abdominal pain. As a result of the examination, she was diagnosed as having acute appendicitis. After conservative treatment, we planned an elective surgery. At 3 months after discharge, laparoscopic appendectomy was performed. We found a mass of 10mm in diameter at the body of the appendix. Histopathological examination revealed the proliferation of heteromorphic cells with small round nuclei. It was positive for chromogranin A and synaptophysin in immunostaining, so we made a diagnosis of NET G1. Tumor cells infiltrated beyond the intrinsic muscle layer, but no vascular invasion was observed, and the margin was negative. In accordance with the guidelines, we followed up the patient with imaging examination and did not find any signs of recurrence.