Mucinous appendiceal neoplasms: Report of a case and brief literature review

INTRODUCTION

Appendiceal tumors are rare neoplasms detected in about 2 % of appendicectomies. The clinical presentation is often unspecific, varying from unspecific abdominal pain or presenting as an acute appendicitis or being asymptomatic.

CASE PRESENTATION

We present a case of a patient presenting as an acute appendicitis with a mucocele, and then classified as HAMN. The patient was treated with initial laparoscopic approach and then conversion in laparotomy with appendectomy. Histology demonstrated a high grade appendiceal mucinous neoplasm limited to submucosa (pT3), with concomitant acute phlegmonous appendicitis. The patient was subsequently sent to a referral center where a right hemicolectomy with HIPEC was performed.

DISCUSSION

HAMN is a rare entity, only recently classified as a new kind of appendiceal mucinous neoplasm. Due to the supposed higher aggressivity, HAMN must be treated as an appendiceal adenocarcinoma. The treatment of this rare entity is not yet well standardized, because of the rarity of this disease.

CONCLUSION

HAMN is a very rare tumor. In the emergency setting, it is mandatory to avoid rupture of the appendix, to minimize the risk of developing pseudomyxoma peritonei. Pathology is essential for further decisions in these patients and plays a very important role in treatment and prognosis.

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

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

Outcomes of laparoscopic single-incision caecal pole resection for low-grade appendiceal mucinous neoplasm

Introduction

Low-grade appendiceal mucinous neoplasm (LAMN) is a rare disease, and its clinical course varies from an incidental finding without symptoms to pseudomyxoma peritonei. Furthermore, there are few established treatment guidelines. This study was designed to confirm the outcomes in patients diagnosed with LAMN who underwent single-incision laparoscopic caecal pole resection.

Patients and Methods

This study was conducted on pathologically confirmed LAMNs from patients who underwent surgery at a single centre, a tertiary institution, from July 2016 to August 2022. Patients diagnosed with LAMN as a result of biopsy were included. All surgeries were performed with single-incision laparoscopic caecal pole resection by a single surgeon.

Results

A total of 70 patients were included. The median age was 65.5 years and 36 (51.4%) patients were female. The baseline carcinoembryonic antigen (CEA) was 8.08 ng/mL (0.76-148.11). The mean maximum diameter was 29.4 mm (7-70) and calcification was seen in 22 cases on pre-operative computed tomography (CT). As a result of histological examination, all patients were marginally negative. The larger the tumour size, the higher the CEA was (P = 0.011), and it was often accompanied by calcification (P = 0.021). In addition, tumour size and CEA showed a positive partial correlation with each other (r = 0.318, P = 0.018). The overall median follow-up period was 22.7 months (2-60). One case had suspected of recurrence on CT scan performed at 33 months following the surgery, but there were no related symptoms.

Conclusion

Single-port laparoscopic caecal pole resection without margin involvement in LAMN was safe and feasible, and showed a favourable long-term outcome.

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

AIM

To review the radiological terminology used to describe dilated mucin-containing appendiceal lesions with correlation to the histopathological diagnosis.

MATERIALS AND METHODS

Radiology and histopathology reports for all patients with an abnormally dilated appendix referred to a tertiary peritoneal malignancy centre, between January 2021 and December 2021, were reviewed.

RESULTS

Overall, 213 patients were included with a median appendiceal diameter of 25.5 mm (range 10-125 mm). Peritoneal disease was present in 109 patients, with the remaining 104 cases demonstrating a dilated appendix only. Local radiology reports were available for 201 cases with the appendix described in 168 cases as appendiceal mucocoele (n=104), appendiceal neoplasm (n=40), appendicitis (n=18), and dilated appendix (n=6). The appendix was not mentioned in 33/201 (15%), either misinterpreted as other pathology (n=15) or not reported (n=18). Peritoneal malignancy histopathology reports were available in 188 cases and reported as low-grade appendix mucinous neoplasm (LAMN, n=144), high-grade appendix mucinous neoplasm (HAMN, n=13), LAMN with foci of HAMN (n=2), LAMN with neuroendocrine tumour (n=2), LAMN with goblet cell adenocarcinoma (n=1), goblet cell adenocarcinoma (n=8), mucinous adenocarcinoma (n=14), non-mucinous adenocarcinoma (n=1), and benign histology (n=3). Only one case of a true inflammatory "mucocoele"/retention cyst was reported.

CONCLUSION

In this cohort of patients, the overwhelming majority of dilated, mucin-filled appendices contained malignant cells and benign mucin-filled appendices were rare. The present authors advocate that the term "likely appendix mucinous neoplasm" should replace "appendix mucocoele" to represent the most likely pathology and facilitate less ambiguous interpretation in management decisions.

Appendiceal mucocele presenting as a leading point in ileocolic intussusceptions: "Case report"

INTRODUCTION AND IMPORTANCE

Appendiceal mucocele is a rare clinical scenario, which is found in 0.2-0.7 % of appendectomies. Ileocecal/ileocolic intusception caused by appendiceal mucocele is an extremely rare condition with few case reports in literatures. The treatment is surgery with the extent determined by intra-operative findings. Ultrasound and CECT scan can suggest the diagnosis, but definitive diagnosis is by histopathology. The aim of this presentation is to discuss appendiceal mucocele in terms of clinical features, diagnostic imaging and treatment. This case report can create awareness to primary care physicians, radiologists, surgeons and pathologists aiding in accurate diagnosis and early surgical intervention to prevent rupture.

PRESENTATION OF THE CASE

A fifty years old woman presented with intermittent colicky peri umbilical abdominal pain of one-week duration. She had nausea, vomiting, mild abdominal distension, and failure to pass feces and flatus. Physical examination was normal. Imaging suggested ileocolic intussusceptions with cystic leading point on ultrasound, but on CECT scan, no leading point reported. Appendiceal mucocele diagnosed intra operatively and confirmed by pathology.

CONCLUSION

Appendiceal mucocele is rare and can be benign or malignant. Preoperative diagnosis is often difficult. Definitive diagnosis is by histopathology. Appendiceal mucocele can rarely present with ileocolic intussusceptions. Radiologists, pathologists, primary care physicians and surgeons must be aware of this condition. Accurate preoperative diagnosis and early surgical treatment of appendiceal mucocele is important to prevent complications like pseudo myxoma peritonei(PMP), which has poor prognosis.

Mucocele of the appendix: what to expect

Mucoceles of the appendix are rare and can have quite variable imaging and clinical presentations, sometimes mimicking an adnexal mass. The underlying cause can be neoplastic or non-neoplastic. The typical imaging appearance of a mucocele of the appendix is that of a cystic structure with a tubular morphology. This structure is defined by having a blind-ending and being contiguous with the cecum. Radiologists should be familiar with key anatomical landmarks and with the various imaging features of mucoceles of the appendix, in order to provide a meaningful differential diagnosis of a lesion in the right lower abdominal quadrant. In addition, a neoplastic mucocele can rupture, resulting in pseudomyxoma peritonei, which will change the prognosis dramatically. Therefore, prompt diagnostic imaging is crucial.

Rare occurrence of pseudomyxoma peritonei (PMP) syndrome arising from a malignant transformed ovarian primary mature cystic teratoma treated by cytoreductive surgery and HIPEC: a case report

Background

Pseudomyxoma peritonei (PMP) syndrome is a disease process that typically occurs from ruptured appendiceal mucocele neoplasms. PMP syndrome arising from malignant transformation of an ovarian primary mature cystic teratoma (MCT) is a pathogenesis rarely encountered.

Case Presentation

Herein, we report a 28-year-old patient evaluated and treated for a right ovarian mass and large volume symptomatic abdominopelvic mucinous ascites. Molecular profiling and genetic analysis revealed mutations in ATM, GNAS, and KRAS proteins while IHC demonstrated gastrointestinal-specific staining for CK20, CDX2, CK7, and SATB2. Peritoneal cytology showed paucicellular mucin. Diffuse peritoneal adenomucinosis (DPAM) variant of PMP arising from a ruptured ovarian primary MCT after malignant transformation to a low-grade appendiceal-like mucinous neoplasm was ultimately confirmed. Treatment included staged therapeutic tumor debulking and right salpingo-oophorectomy followed by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC).

Conclusions

Our report builds upon the existing literature supporting this aggressive treatment option reserved for advanced abdominal malignancies utilized in this patient with a rare clinical entity.

Necessity of posttreatment surveillance for low-grade appendiceal mucinous neoplasms

BACKGROUND AND OBJECTIVES

Low-grade appendiceal mucinous neoplasms (LAMNs) are generally treated by surgical resection, but posttreatment surveillance protocols are not well-established. The objectives of this study were to characterize posttreatment surveillance and determine the risk of recurrence following surgical resection of LAMN.

METHODS

Patients who underwent surgical resection of localized LAMNs in an 11-hospital regional healthcare system from 2000 to 2019 were identified. Posttreatment surveillance regimens were characterized, and rates of disease recurrence were evaluated.

RESULTS

A total of 114 patients with LAMNs were identified. T-category was pTis for 92 patients (80.7%), pT3 for 7 (6.1%), pT4a for 14 (12.3%), and pT4b for 1 (0.9%). Two patients (1.8%) had a positive resection margin. Posttreatment surveillance was performed for 39 (34.2%) patients and consisted of office visits for 32 (82%) patients, computerized tomography imaging for 30 (77%), magnetic resonance imaging for 5 (13%), colonoscopy for 15 (38%), and serum tumor marker measurement for 12 (31%). After a mean follow-up duration of 4.7 years, no patients experienced tumor recurrence.

CONCLUSIONS

Posttreatment surveillance is common among patients with LAMNs. However, no patients experienced tumor recurrence, regardless of T-category or margin status, suggesting that routine surveillance following surgical resection of LAMN may be unnecessary.

Standardization of the pathologic diagnosis of appendiceal mucinous neoplasms

Although the understanding of appendiceal mucinous neoplasms (AMNs) and their relationship with disseminated peritoneal mucinous disease have advanced, the diagnosis, classification, and treatment of AMNs are still confusing for pathologists and clinicians. The Gastrointestinal Pathology Study Group of the Korean Society of Pathologists (GPSG-KSP) proposed a multicenter study and held a workshop for the “Standardization of the Pathologic Diagnosis of the Appendiceal Mucinous Neoplasm” to overcome the controversy and potential conflicts. The present article is focused on the diagnostic criteria, terminologies, tumor grading, pathologic staging, biologic behavior, treatment, and prognosis of AMNs and disseminated peritoneal mucinous disease. In addition, GPSG-KSP proposes a checklist of standard data elements of appendiceal epithelial neoplasms to standardize pathologic diagnosis. We hope the present article will provide pathologists with updated knowledge on how to handle and diagnose AMNs and disseminated peritoneal mucinous disease.

Impending Rupture With a Twisted Huge Appendiceal Mucocele Treated With Totally Laparoscopic Resection: A Case Series

Torsion of the appendix is rare, and appendiceal mucocele can be one of its causes. The first case was of a 49-year-old man who visited the emergency room (ER) for abdominal pain. Abdominal computed tomography (CT) showed appendiceal mucocele with suspected torsion and rupture. The patient underwent laparoscopic exploration and appendectomy. The second case was of a 69-year-old man who visited the ER for epigastric pain. Abdominal CT showed suspicious appendiceal mucocele with ischemic change, indicating torsion of the appendix. The twisted appendix was successfully removed by laparoscopic exploration. An appendiceal mucocele is one of the causes of twisted appendix. With torsion, the mucocele can be diagnosed as rupture by ischemia which may lead to pseudomyxoma peritonei. For this reason, open laparotomy has traditionally been preferred. However, an unruptured appendiceal mucocele or impending rupture with torsion of the appendiceal mucocele can be treated with totally laparoscopic surgery.

Diagnosis and Treatment of Primary Tumors of the Appendix: a Critical Review

INTRODUCTION

The aim of the current paper was to critically collect, select and summarize the evidence regarding diagnosis, treatment and follow up of primary tumors of the appendix.

METHODS

A literature review was performed by search and review of the scientific studies pertaining to the subject of our inquiry.

RESULTS

Recommendations regarding pimary tumors of the appendix were formulated on the basis of the collected evidence. CONCLUSION : Primary tumors of the appendix are rare and a high index of suspicion is required not to miss a potentially life threatening medical condition.

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.

A general overview of mucocele of appendix

Mucocele of the appendix is a very rare disease entity that often discovered incidentally during surgery. It can result from both non-neoplastic and neoplastic lesions and histopathological examination is needed for confirmation. Failure to make an early preoperative diagnosis may results in its rapture and spillage of mucin contents into the peritoneal cavity leading to a disastrous complication of pseudomyxoma peritonei (PMP) that has a very bad prognosis. A clear pathological terminology and management strategies of appendiceal mucocele (AM) is lacking. This literature review aims to derive detailed information related to clinical significance of AM to avoid complication of PMP and plan appropriately during surgery according to the current evidence. The relevant articles from scientific databases such as Medline, PubMed, Google Scholar were searched and extracted using the keywords “mucocele appendix” “cystadenoma%”. Data based on epidemiology, clinical manifestations, complications, pathology, diagnostic work up and management were analyzed and summarized. A meticulous surgical excision is the mainstay of treatment and open surgical approach is still preferred over laparoscopy. Preoperative diagnosis of AM is very imperative as it may harbour neoplasm and can be made utilising the imaging tools like computed tomography and ultrasonography. Primary care physicians can have a crucial role in making early detection and timely referral for appropriate management in order to avoid complications. After appendectomy, 5-year survival rate for the simple AM is 91%-100% but it reduces to 25% for the malignant AM.

Outcomes in cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for maximal volume (PCI 39) appendiceal tumours

BACKGROUND

Higher Peritoneal Cancer Index (PCI) requires more extensive surgery and maybe associated with more limited outcomes. The aim of this study in a high-volume centre in Australia was to analyse the outcomes in PCI 39 patients regarding short and long term outcomes in appendiceal tumours.

METHODS

A retrospective analysis of prospectively maintained database of patients that underwent primary cytoreductive surgery (CRS) + hyperthermic intraperitoneal chemotherapy (HIPEC) with PCI 39 at St George Hospital, Sydney from 1996 to 2018. Patients with appendiceal tumours (inclusive of high and low grade) were analysed. Factors contributing to high grade (III/IV Clavien-Dindo) morbidity and mortality were assessed.

RESULTS

Of the 1201 patients in the database, 58 patients had a PCI 39 from appendix tumours at their first operation. The overall survival rate at 1, 3 and 5 year was 91.2%, 79.5% and 62.9% respectively. The median survival was 87.2 months (96% CI 51.8-NR). The rate of major morbidity was 71%. The postoperative mortality incidence was 1.7%. The median hospital length of stay was 34 days (IQR:27-54 days).

CONCLUSIONS

In an experienced centre CRS + HIPEC is safe in selected patients with PCI 39. Despite the high morbidity, the overall survival for appendiceal tumours appear considerably better than debulking surgery.