Predicting Underlying Neoplasms in Appendiceal Mucoceles at CT: Focal Versus Diffuse Luminal Dilatation

A Case of Low-Grade Appendiceal Mucinous Neoplasm: The Role of Preoperative Imaging and Surgical Technique in Achieving Favorable Outcomes

Appendiceal mucinous neoplasms may present without symptoms or with chronic pain in the right lower quadrant. This report describes a case of a 35-year-old woman who presented with chronic right lower quadrant pain and was found to have a low-grade appendiceal mucinous neoplasm (LAMN). Physical examination revealed localized tenderness in the right lower quadrant with no additional symptoms. Preoperative laboratory results were normal, and a CT scan revealed a cystic appendiceal lesion with an internal calcification, initially mistaken for a fecalith, which led to the decision for exploratory laparotomy. Intraoperative findings confirmed the presence of a cystic-like appendiceal lesion, and an open appendectomy was performed. Histopathological examination revealed a low-grade appendiceal mucinous neoplasm (LAMN) confined to the mucosa, without evidence of metastatic disease. The patient had an uneventful recovery and required no additional treatment. This case highlights that surgical intervention with proper technique for confined appendiceal neoplasms, combined with effective preoperative imaging and thorough histopathological examination, is crucial for diagnosis and effective management, ensuring favorable outcomes.

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.

High Incidence of Appendiceal Neoplasms in the Elderly: A Critical Concern for Non-Surgical Treatment

OBJECTIVE

Appendiceal neoplasms (ANs) are rare tumors that are often discovered incidentally during histopathological examinations. The increasing incidence of ANs is a critical issue in the non-operative management of acute appendicitis. This study aimed to document the temporal trends over a 12-year period by analyzing the clinical presentation, imaging findings, and histopathological features of ANs.

SUBJECTS AND METHODS

Health records of patients who underwent appendectomy from 2011 to 2022 were examined. Demographic and clinical data, laboratory results, imaging findings, and histopathological features were documented. The characteristics of both ANs and non-neoplastic cases were evaluated.

RESULTS

A total of 22,304 cases were identified, of which 330 (1.5%) were diagnosed with ANs. The odds ratio for ANs increased with age, with the highest odds ratio observed in patients aged 70 or older. Receiver Operating Characteristic analysis showed that age and appendiceal diameter were significant predictors of ANs. An optimal age cut-off point of 28.5 years was determined, yielding a sensitivity of 72% and a specificity of 64%. For appendiceal diameter, the optimal cut-off was found to be 9.5 mm, exhibiting a sensitivity of 77% and a specificity of 56%.

CONCLUSION

Although the incidence of ANs remains relatively low, a steady increase has been observed over the past decade. The increasing rate of ANs raises concerns regarding non-surgical management options. The results of this study highlight the importance of considering ANs as a potential diagnosis in older patients and in patients with an appendix diameter greater than 9.5 mm. These findings may have implications for treatment and management.

Review of appendicitis: routine, complicated, and mimics

Appendicitis is one of the most common sources of abdominal pain in the emergency setting and is generally considered a straightforward diagnosis. However, atypical appearances, non-visualization, and inconclusive features can make these cases more complicated. The objectives of this article are to review the differential diagnoses for right lower quadrant pain, discuss the imaging characteristics of simple appendicitis on computed tomography (CT), and provide guidance for equivocal cases, complicated appendicitis, and appendicitis mimics. This review will also discuss the identification and management of neoplasms of the appendix.

A Case Report on Life-Threatening Lower Gastrointestinal Bleeding: A Rare Presentation of Mucinous Adenocarcinoma of the Appendix

Introduction

A life-threatening lower gastrointestinal bleeding from mucinous adenocarcinoma of the appendix is a rare occurrence. Diagnosing and management of such a condition are challenging. Case Presentation. A 73-year-old male with a history of type 2 diabetes mellitus and hypertension presented with intermittent per rectal bleeding for two weeks, which progressed to the passage of a large number of blood clots and fresh blood. He had features of class III shock on admission. An endoscopic evaluation followed initial resuscitation to locate the source of bleeding. Colonoscopy revealed a large blood clot at the opening of the appendicular orifice with no active bleeding. Oesophagoduodenoscopy, contrast-enhanced CT abdomen, and CT angiogram findings were unremarkable. Due to repeated episodes of rebleeding leading to haemodynamic instability, an exploratory laparotomy was performed. A retrocaecal appendix was noticed with a macroscopically suspicious-looking dilated tip adhered to the posterior caecal wall. Right hemicolectomy was performed as the lesion was suspicious and to stop bleeding from the site. Ileocolic side-to-side hand-sewn anastomosis was performed using 3/0 polyglactin. Postoperatively, per rectal bleeding was settled. Microscopy revealed appendiceal mucinous adenocarcinoma with AJCC staging of pT3NoMx. The patient was discharged on postoperative day seven and referred to oncological management. He was offered six cycles of chemotherapy with capecitabine and oxaliplatin. At the six-month follow-up visit, the patient had no features of recurrence clinically.

Conclusion

Mucinous adenocarcinoma of the appendix can rarely present as life-threatening lower GI bleeding. Prompt resuscitation, endoscopic evaluation, and operative management with right hemicolectomy and chemotherapy provided a good outcome.

Single-incision laparoscopic surgery compared to conventional laparoscopic surgery for appendiceal mucocele: a series of 116 patients

BACKGROUND

Although the safety and feasibility of conventional laparoscopic surgery (CLS) for appendiceal mucocele (AM) has been reported, studies on single-incision laparoscopic surgery (SILS) for AM have not been reported. Here, we aimed to compare the perioperative and short-term outcomes between SILS and CLS for AM and to evaluate the oncological safety of SILS.

METHODS

We retrospectively analyzed the medical records of patients, diagnosed based on computed tomography findings, who underwent laparoscopic surgery for AM between 2010 and 2018 at one institution. We excluded patients strongly suspected of having malignant lesions and those with preoperative appendiceal perforation. Patients were divided into two groups-CLS and SILS. Pathological outcomes and long-term results were investigated. The median follow-up period was 43.7 (range: 12.3-118.5) months.

RESULTS

Ultimately, 116 patients (CLS = 68, SILS = 48) were enrolled. Patient demographic characteristics did not differ between the groups. The preoperative mucocele diameter was greater in the CLS than in the SILS group (3.2 ± 2.9 cm vs. 2.3 ± 1.4 cm, P = 0.029). More extensive surgery (right hemicolectomies and ileocecectomies) was performed in the CLS than in the SILS group (P = 0.014). Intraoperative perforation developed in only one patient per group. For appendectomies and cecectomies, the CLS group exhibited a longer operation time than the SILS group (63.3 ± 24.5 min vs. 52.4 ± 17.3 min, P = 0.014); the same was noted for length of postoperative hospital stay (2.9 ± 1.8 days vs. 1.7 ± 0.6 days, P < 0.001). The most common AM etiology was low-grade appendiceal mucinous neoplasm (71/116 [61.2%] patients); none of the patients exhibited mucinous cystadenocarcinoma. Among these 71 patients, there were 8 patients with microscopic appendiceal perforation or positive resection margins. No recurrence was detected.

CONCLUSIONS

SILS for AM is feasible and safe perioperatively and in the short-term and yields favorable oncological outcomes. Despite the retrospective nature of the study, SILS may be suitable after careful selection of AM patients.

Retrospective case-control study to predict a potential underlying appendiceal tumor in an acute appendicitis context based on a CT-scoring system

OBJECTIVES

To assess CT signs to discriminate an appendiceal tumor versus a non-tumoral appendix in an acute appendicitis context.

METHODS

A 10-year bicentric retrospective case-control study was performed in adults. Patients with a histopathological appendiceal tumor and appendicitis were paired for age and sex with patients with non-tumorous appendicitis (1/3 ratio, respectively). Two senior radiologists blindly analyzed numerous CT findings with final consensus to perform univariate and multivariate statistical analyses. A diagnostic CT scan score was calculated with a bootstrap internal validation. Reproducibility was assessed based on the kappa statistic.

RESULTS

A total of 208 patients (51 +/- 21 years; 114 males) were included (52 patients in the tumor group and 156 in the non-tumor group). In the multivariate analysis, an appendicolith and fat stranding were protective factors with OR = 0.2 (p = 0.01) and OR = 0.3 (p = 0.02), respectively, while mural calcifications (OR = 47, p = 0.0001), an appendix mass (OR = 7.1, p = 0.008), a focal asymmetric wall abnormality (OR = 4.9, p = 0, 001), or a ≥ 15 mm diameter (OR = 3.5, p = 0.009) were positive predictive factors of an underlying tumor. Using a ≥1 cut-off, our diagnostic score had an AUC = 0.87 (95 % CI, 0.82-0.93) and a positive likelihood ratio = 13.5 (95 % CI, 6.7-27.1).

CONCLUSION

We developed a reliable scoring system based on CT findings, which is highly predictive of an underlying appendiceal neoplasm in an appendicitis context using a ≥1 cut-off.

A prospective study of discrepancy between clinical and pathological diagnosis of appendiceal mucinous neoplasm

Purpose

Appendiceal tumoral lesions can occur as benign, malignant, or borderline disease. Determination of the extent of surgery through accurate diagnosis is important in these tumoral lesions. In this study, we assessed the accuracy of preoperative CT and identified the factors affecting diagnosis.

Methods

Patients diagnosed or strongly suspected from July 2016 to June 2019 with appendiceal mucocele or mucinous neoplasm using abdominal CT were included in the study. All the patients underwent single-incision laparoscopic cecectomy with the margin of cecum secured at least 2 cm from the appendiceal base. To compare blood test results and CT findings, the patients were divided into a mucinous and a nonmucinous group according to pathology.

Results

The total number of patients included in this study was 54 and biopsy confirmed appendiceal mucinous neoplasms in 39 of them. With CT, the accuracy of diagnosis was 89.7%. The mean age of the mucinous group was greater than that of the nonmucinous group (P = 0.035). CT showed that the maximum diameter of appendiceal tumor in the mucinous group was greater than that in the nonmucinous group (P < 0.001). Calcification was found only in the appendix of patients in the mucinous group (P = 0.012). Multivariate analysis revealed that lager tumor diameter was a factor of diagnosis for appendiceal mucinous neoplasm.

Conclusion

The accuracy of preoperative diagnosis of appendiceal mucinous neoplasms in this study was 89.7%. Blood test results did not provide differential diagnosis, and the larger the diameter of appendiceal tumor on CT, the more accurate the diagnosis.