Mucus containing cystic lesions "mucocele" of the appendix: the unresolved issues

Acellular Appendix Vermiform Mucinous Neoplasm

Appendiceal neoplasms are usually asymptomatic or associated with mild, nonspecific symptoms. Due to the rarity of the disease and the lack of specific symptoms, this clinical entity escapes the diagnostic consideration of the gynecologist, when women come in with right iliac fossa pain. A case is presented of a 56-year-old woman with a mass in the right small pelvis, which was preoperatively diagnosed as originating from the ovary. An exploratory laparotomy followed in which the uterus and appendages were found to be macroscopically normal, while the mass described above came from the appendix, extended into the anatomical area of the right accessory, and was in contact with the atrophic right ovary. The appendix vermiformis was removed intact. The final pathologic examination confirmed an acellular mucinous tumor of the appendix. Accurate preoperative diagnosis of mucoceles is extremely difficult to make. The formation is discovered in a random imaging test, and the diagnosis is confirmed only intraoperatively.

Diagnostic Challenges and Treatment Options for Mucocle of the Appendix: A Comprehensive Review

Mucocles of the appendix, encompassing mucinous cystadenomas and mucinous cystadenocarcinomas, represent rare but clinically significant appendiceal lesions characterized by the accumulation of mucin within the appendix lumen. This review explores the diagnostic complexities and treatment strategies associated with mucocles, emphasizing the importance of its accurate recognition and management. Diagnostic challenges arise due to overlapping symptoms with acute appendicitis and other appendiceal pathologies, necessitating a multidimensional approach that includes imaging, histopathological analysis, and clinical correlation. Treatment options range from appendectomy for benign lesions to more extensive surgical procedures, such as right hemicolectomy for malignant forms. Prognostic factors, including histological subtype and tumor size, influence treatment decisions and long-term outcomes. By synthesizing current evidence and clinical insights, this review aims to provide a comprehensive framework for clinicians to navigate the complexities of mucocles of the appendix, offering perspectives that can guide effective management and future research endeavors.

Vermiform Appendix and the Potential for Missed Pathologies

Introduction

The appendix is considered an appendage of little value and is often treated disdainfully, be it as part of evolutionary process, on a grossing table, under a microscope or while archiving specimens and slides. It is only recently, with data indicating its importance in gut immunity and as the origin of pseudomyxoma, that its space in a human body appears vindicated.

Aim

Our aim was to screen the histopathologic spectrum of appendix lesions observed in our hospital for rare, incidental or clinico-radiologically uncertain lesions that would help emphasize a necessary seriousness in its sampling.

Method

All appendectomy specimens over ten years were screened for diagnosis other than acute/chronic/resolving appendicitis and pseudomyxoma peritonei. Among the recorded rare diagnoses, one representative case each, based on interesting history or pathology, was selected for discussion.

Observation

Forty-three lesions were found to meet inclusion criteria comprising 12 varied etiologies. Among these, 25 had a normal-appearing appendix and 27 were not suspected on radiology or on clinical/surgical assessment. Histopathology comprised, among others, neoplastic entities such as (Diffuse large B-cell) lymphoma, metastasis, carcinoid as well as interesting non-neoplastic diagnoses such as pinworm infestation (in the elderly) and (post-menopausal) endometriosis.

Conclusion

Sampling and histopathologic assessment of the appendix should be compulsory, careful and representative. Each specimen must be treated as harboring a potential pathology, until microscopically proven otherwise because missed “rare” diagnoses could delay therapy or alter key management decisions as cancer staging.

Retrospective analysis of 9 cases of appendiceal mucocele in 3,071 cases of appendicitis

Appendiceal mucocele is a rare disease. Due to the lack of specific clinical symptoms, and the high misdiagnosis rate before operation, in the present study, the clinical data were assessed to determine a potential basis for the diagnosis and treatment of appendiceal mucocele. The clinical data of 3,071 patients with appendicitis admitted between January 2014 and July 2021, including 9 patients with appendiceal mucoceles were retrospectively analyzed. The data were retrieved from the hospital records and included the patients' age, sex, leukocyte counts (measured in the peripheral venous blood sample), the surgical methods, the pathological results and the postoperative follow-up information. Among the 3,071 patients with appendicitis, 9 cases were appendiceal mucocele. These 9 were treated by laparoscopic surgery in 6 cases (2 laparoscopic appendectomy, 2 laparoscopic partial cecectomy plus appendectomy, and 2 laparoscopic right hemicolectomy) and laparotomy in 3 cases (partial cecectomy plus appendectomy). Pathological examination was performed on the surgically resected specimens of all patients. The results showed that 7 cases were appendiceal mucoceles, and 2 cases were low-grade appendiceal mucoceles. During the follow-up after surgery, one patient with exploratory laparotomy plus partial cecectomy and appendectomy was pathologically diagnosed with low-grade appendiceal myxoma. The patient developed peritoneal implants appeared 2 years later, and the remaining patients are still alive, without any postoperative complications or obvious signs of recurrence. Appendiceal mucocele is a disease that usually causes clinical manifestations of acute appendicitis. Ultrasound and CT scans can be used for preoperative diagnosis. The surgical treatment options for mucoceles are open or laparoscopic appendectomy, cecectomy, and right hemicolectomy. Although the incidence of appendiceal mucocele is low, special attention should be paid to surgery due to its predisposition to peritoneal implantation and metastasis. Laparoscopic appendectomy with partial cecectomy is not a difficult procedure and is not likely to cause abdominal implantation metastasis, thus it should be the preferred surgical method. When conditions permit, intraoperative rapid cryotherapy can quickly identify the occurrence of malignant tumors.

Low-Grade Appendiceal Mucinous Neoplasm (LAMN) Primarily Diagnosed as an Ovarian Mucinous Tumor

BACKGROUND

Low-grade appendiceal mucinous neoplasms (LAMN) are detected in 0.7 to 1.7% of all appendicectomies. The diagnosis can be challenging, particularly in female patients where the differential diagnosis of primary appendiceal and ovarian mucinous neoplasms is unclear. Case Presentation. A 71-year-old female was referred to our tertiary hospital with the working diagnosis of a right ovarian cystic tumor. The lesion was identified through a transvaginal ultrasound performed for vague lower abdominal pain symptoms. CT scan confirmed these findings. Intraoperatively, an appendiceal mucocele was identified and a right hemicolectomy was performed. The histopathology examination revealed a LAMN. Six months later, the patient remains disease-free. A close biannual oncological follow-up has been suggested.

CONCLUSION

This case underlines the difficulty in determining the origin of mucinous neoplasms of the right pelvic area. Mucocele of the appendix should be considered in the differential diagnosis of a mass in the right iliac fossa.

Epidemiology, histopathology, clinical outcomes and survival of 50 cases of appendiceal mucinous neoplasms: Retrospective cross-sectional single academic tertiary care hospital experience

Background

Appendicular neoplasms are rare, most commonly as carcinoids followed by appendicular mucinous neoplasms (AMN). To date, there remains controversy regarding the best treatment of AMN and factors affecting its prognosis.

Method

Retrospective chart review of patients operated for appendicular pathology (January 2011–December 2018, follow up to December 2020) at our institution. For all AMN patients, data included pre-operative clinical presentation, and operative/post-operative findings.

Results

12454 patients underwent appendectomy, of whom 50 (0.4%) had AMN histopathologically (mean age = 47.2). Most patients had laparoscopic appendectomy as primary surgery. Low grade AMN was the most common subtype (n = 41, 82%), and pseudomyxoma peritonei (PMP) was found in 8 (16%) patients. Based on histopathology and margin involvement, the 50 patients were categorized into 3 prognostic categories of recurrence risk (no risk, 24 patients; low risk, 8; high recurrence risk, 18 patients). Disease-free survival (DFS) was lowest for high recurrence risk group (P < 0.001). Eleven (22%) patients had AMN involving resection margin, of whom 3 had no completion surgery and had no recurrence. Higher tumor markers were associated with lower DFS, however it was not statistically significant.

Conclusion

AMNs are rare but serious due to the risk of PMP. Laparoscopic approach for AMN may be feasible. Prognostic categories were significantly inversely correlated with recurrence risk; hence useful in predicting prognosis. Contrary to previous proposals, AMNs with acellular mucin at margin or local acellular mucin spillage may not require secondary surgery, especially if the patient is in low recurrence risk group. Tumor markers may predict risk of recurrence.

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Laparoscopic approach may be feasible for appendiceal mucinous neoplasms (AMN).

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AMN can be categorized into 3 risk recurrence groups (No risk, low, and high).

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AMN with acellular mucin at the margin may not require secondary surgery.

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Higher tumor markers may indicate high risk of AMN recurrence.

Appendiceal mucocele secondary to torsion in an asymptomatic patient

Torsion of the appendix associated with an appendiceal mucocele is extremely rare with just a few published cases. To our knowledge, we report the first case of appendiceal mucocele secondary to torsion in an asymptomatic patient. In this case, numerous adhesions were found attaching the tip of the appendix mucocele to the peritoneum contributing to torsion as well as a lack of evidence for appendiceal neoplasm. Complications of appendiceal mucocele include obstruction, intussusception and pseudomyxoma peritonei, which has a particularly poor prognosis. Clinicians should, therefore, consider prompt surgical resection for definitive histopathological diagnosis and management.

Dilated Appendix: Is There More to It? Case Report and Brief Review of Literature with Radiologic-Pathological Correlation

Mucocele of the appendix is rare and represents only the tip of the iceberg of underlying benign and malignant pathological processes. Intraoperative diagnosis is also tricky because the inflammation of the appendix often hides the tumor. The preoperative diagnosis is essential to differentiate appendiceal mucocele from acute appendicitis as the treatment varies from open surgical versus laparoscopic surgical approach and for decreasing intraoperative and postoperative morbidity and mortality rate. We present three cases of appendiceal mucocele. The purpose of this paper is to make the physicians aware of the entity, its associations and the effect on management. This review will provide radiologic and pathologic correlation for the preoperative diagnosis of benign and malignant causative processes and differential diagnostic considerations.

Laparoscopic Resection of an Appendix Mucocele in a Breast Cancer Patient

Background

Acute appendicitis may be treated with antibiotics, but most surgeons offer laparoscopic appendectomy (LA). Appendiceal mucocele (AMC) is a rare disorder. Surgical removal is recommended due to the risk of pseudomyxoma peritonei. LA has been suggested for this condition. Although rare, breast cancer (BC) may metastasize to the appendix. An appendiceal mass in a breast cancer patient should be approached as a possible metastatic focus until proven otherwise.

Case Presentation

A 45-year-old Caucasian woman with invasive lobular BC underwent bilateral mastectomy. An AMC was found on CT scan. LA was done with a strict minimal touch technique. The appendix was resected with a 1 cm margin of the cecal pole, and the specimen was removed from the abdomen in a retrieval bag. Pathology showed benign cystadenoma. The patient had an uneventful postoperative course.

Conclusion

This case highlights the diagnostic challenge of an appendiceal mass in a BC patient. BC patients with AMC should undergo appendectomy to rule out metastatic disease and to prevent pseudomyxoma peritonei. LA can be performed safely in patients with AMC.

Clinicopathological Features and Management of Appendiceal Mucoceles: A Systematic Review

Appendiceal mucoceles (AMs) are rare mucin-containing neoplasms with malignant potential. Lack of evidence-based data exists defining clinicopathological features for management. MEDLINE search between 1995 and 2015 was performed using search criteria “Appendix mucocele.” Systematic review of patient-, pathologic-, and treatment-related characteristics was performed and data analyzed. Among 276 cases of non-perforated AMs, 163 (59%) patients were female, with variable and nonspecific presentation. Patients were treated with appendectomy (52.1%), right hemicolectomy (17.6%), partial cecectomy (17.2%), and ileocecetomy (13.1%). Pathologic evaluation revealed the following: cystadenoma/low-grade appendiceal mucinous neoplasm (54%), unspecified/benign (25%), retention cyst (14.1%), cystadenocarcinoma (4.2%), and mucosal hyperplasia (2.9%). All 11 (4.2%) patients with cystadenocarcinoma were female ( P = 0.004), odds ratio for malignancy 1.07 times higher for women. Synchronous colonic malignancy was reported in three patients (27%) with cystadenocarcinoma ( P = 0.007), odds ratio of 12.1. AMs have low risk for malignancy. Treatment should begin with appendectomy-only and subsequently guided by pathologic diagnosis.

Appendiceal mucinous neoplasms: an uncertain nosological entity. Report of a case

INTRODUCTION

Appendiceal mucocele is a relatively rare condition characterized by progressive dilation of the appendix caused by intraluminal accumulation of mucoid substance. Its incidence is 0.07 - 0,63% of all appendectomies performed.

CASE REPORT

We report the case of a 70-year-old man who came to our observation with gravative pain in right lower abdominal region. A computed tomography abdominal scan revealed a cystic/tubular structure like an appendicular mass with wall enhancement but without calcifications suggestive of a mucocele. Into peritoneal cavity we found profuse mucinous material with a 1,5 cm size parietal nodule. We also identified a free perforation of the cecum with consensual spillage of gelatinous material mimicking a pseudomyxoma peritonei. We decided to perform a right hemicolectomy with excision of peritoneal lesion.

DISCUSSION

The controversy in the pathologic terminology can give rise to a clinical dilemma in terms of the management and follow-up plans. For mucosal hyperplasia and cystadenoma simple appendectomy is curative. Only in case of large base of implantation it may be necessary the resection of the ileum and caecum or right hemicolectomy. In case of mucinous cystoadenocarcinoma authors perform a right hemicolectomy.

CONCLUSION

Appendiceal mucinous neoplasms are different pathological entities. The correct surgical management depends on size and location of lesion. A preoperative diagnosis is obviously needed in order to perform the correct treatment. CT abdominal scan is the better diagnostic tool, but different authors show their inability to reach a preoperative diagnosis in the larger majority of cases.

Unusual Entities of Appendix Mimicking Appendicitis Clinically - Emphasis on Diagnosis and Treatment

BACKGROUND

Abdomen is considered a magic box or a Pandora box where you will get different, unexpected pathologies along with rare entities. Appendicitis is the commonest emergency in surgery which presents challenges to surgeons because of a myriad list of differential diagnosis including both medical and gynaecological pathologies. Preoperative imaging plays an important role in diagnosis and management.

AIMS AND OBJECTIVES

To study the rare atypical anatomical and surgical presentations of appendix in patients with clinical features of appendicitis. We focus on the clinical features and the role of investigations for the radiological part and management.

MATERIAL AND METHODS

This study was done in M.M. Institute of Medical Sciences and Research, Mullana, Ambala, from November 2014 to July 2016. This was a retrospective study. We found 168 cases with the diagnosis of appendicitis, out of which 19 were with rare entities.

RESULTS

Subjects of both genders were aged between 20 and 60 years. Out of 19, 15 were males and 4 females. Four patients were operated for inguinal hernia but incidentally we found appendix in the hernial sac termed as Amyand's hernia. Another patient presented with obstruction and appendix was forming a band diagnosed as torsion of appendix. Two most interesting cases were diagnosed as appendicular neuralgia and relieved by appendectomy. Out of 19 cases, 7 cases were operated for appendicitis diagnosed as appendicolith. In all the cases appendectomy was done without encountering any complications. Symptom free patients were operated for appendicular neuralgia. No malignancy was found in mucocele appendix at follow up. There were no complications by the 6-month follow-up.

CONCLUSION

As we came across with different entities of appendix presented with appendicitis, patients should be investigated before proceeding for surgery. In our study, there were incidental findings for which surgeons were not aware of the diagnosis and even for the patient. In inguinal hernia, ultrasonography was not done, diagnosis being made on clinical basis. Clinical and radiological investigations play an important part in early diagnosis and management.

Giant Appendicular Mucocele Due to Mucinous Cystadenoma

Mucocele of the appendix is a rare clinicopathological entity simulating acute appendicitis. The most common form of the mucocele is cystadenoma, which is characterized by luminal dilatation producing large amounts of mucin. We present a new case of a giant mucocele of appendix with mucinous cystadenoma. A 61-year-old female was admitted with complaints of severe lower right quadrant pain. Ultrasonography and computed tomography (CT) suggested that it was a mucocele, but due to severity of pain, she underwent an emergency operation. Fortunately, without a perforation, it was a giant mucocele and the operation was terminated with an uneventful appendectomy with segmental cecal resection. The histopathological evaluation of the specimen reported to be a mucocele with mucinous cystadenoma with negative surgical margins. The patient was discharged postoperative 6th day, and a control colonoscopy and abdominal CT was planned for 6 months following surgery. Appendicular mucocele is rare and difficult to diagnose preoperatively, and sometimes it may be of large size which increases the risk of perforation. Pseudomyxoma peritonei (PP) is the most feared complication of mucocele perforation. Appendectomy with negative margins is a requirement for adequate treatment for most cases. Utmost care should be taken during surgery to avoid perforation of mucocele.

How to cite this article

Sertkaya M, Emre A, Pircanoglu EM, Peker O, Cengiz E, Karaagaç M. Giant Appendicular Mucocele Due to Mucinous Cystadenoma. Euroasian J Hepato-Gastroenterol 2016;6(2):186-189.

A giant mucinous cystadenocarcinoma of the appendix: a case report and review of the literature

BACKGROUND

Mucinous cystadenocarcinoma is the second most common etiology of appendiceal mucocele. We report a relatively rare case of a giant appendiceal mucocele caused by mucinous cystadenocarcinoma, which occupied the entire abdomen of an adult woman.

CASE PRESENTATION

A 63-year-old woman presented with a chief complaint of abdominal distention. Imaging studies showed a giant cystic mass occupying her entire abdomen. Laparotomy confirmed a giant appendiceal mucocele, and the patient underwent ileocecal resection. A mucinous deposit was not found in her abdominal cavity, and the ovaries were grossly normal bilaterally. The pathological diagnosis was mucinous adenocarcinoma with a low-grade mucinous neoplasm that invaded the subserosa. Regional lymph node metastasis was not found. She has had recurrence-free survival for 5 years.

CONCLUSIONS

The present case is the largest appendiceal cystadenocarcinoma ever reported. The optimal treatment of an appendiceal neoplasm requires further research based on consensus terminology of an appendiceal mucocele.

Mucocele of the Appendix: Dilemmas in Differential Diagnosis and Therapeutic Management

Mucocele of the appendix (AM) is a descriptive term for mucinous distension of the appendiceal lumen. It refers to the progressive retrograde dilatation of the vermiform appendix. Because of a lack of specific signs or due to its sometime quiet presentation, this condition is frequently diagnosed only at an advanced stage. We present three isolated cases of AM complicated by the development of acute inflammation of the appendix. Currently, the assessment of appendiceal lesions relies heavily on Ultra Sonography (US) as the primary diagnostic tool. This however may not always identify the origin of such a tumour. Therefore, additional investigative modalities are implemented. Despite recent research on the therapeutic strategies against appendiceal neoplastic disorders, surgical resection appears the only potentially curative approach. Accepted management includes appendectomy, right hemicolectomy, partial colectomy with debulking or palliative resection combined with additional chemotherapy. Even if laparoscopy has been successfully used to perform appendectomy, some concerns exist regarding its use in dealing with mucinous secreting lesions because of possible spillage of mucin intra-operatively. The aim of this investigation was to analyze all cases of AM complicated by the development of acute inflammation of the appendix presented in our institution. The relevant literature is briefly reviewed. Clinical features, diagnostic approach and management algorithm for appendiceal lesions are also discussed.