Appendiceal Mucinous Neoplasm Research Articles

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.

Active surveillance for low-grade appendiceal mucinous neoplasm (LAMN).

Due to the scarcity of low-grade appendiceal mucinous neoplasm (LAMN), there is an absence of systematized guidelines concerning its management, especially after incidental finding on an appendiceal specimen. In this study, we evaluate the active surveillance (AS) strategy adopted for a series of patients diagnosed with LAMN on resection specimens who were considered to have a low risk of pseudomyxoma progression. Thirty patients were included between April 2014 and July 2021, with a female majority and a median follow-up period of 3.1 years. The inclusion criteria were as follows: LAMN diagnosis on appendiceal specimens, confirmed in an expert center, limited extra-appendiceal mucin resected and localized around the appendix, normal biology (CEA, CA199, CA125) and normal abdominopelvic MRI. AS included physical exam (trocar scar), biology and MRI, 6months postoperatively, then yearly for 10 years. As an initial surgery, 77 % had an appendectomy as their initial intervention, 17 % had a cecectomy, and 6 % had a right colectomy. After follow-up, 87 % of patients showed no sign of disease progression by MRI, while 13 % progressed to PMP. MRI performed in the first postoperative year predicted the disease prognosis in 97 % of patients. The AS strategy, based on MRI, is a valid option after incidental LAMN diagnosis.

Goblet Cell Adenocarcinoma in the Background of a Ruptured Appendiceal Diverticulum Mimicking Low-grade Appendiceal Mucinous Neoplasm: A Case Report and Literature Review

Goblet Cell Adenocarcinoma in the Background of a Ruptured Appendiceal Diverticulum Mimicking Low-grade Appendiceal Mucinous Neoplasm: A Case Report and Literature Review

Evaluation of appendiceal mucinous neoplasms by curved linear-array echoendoscope: A preliminary study.

Preoperative diagnosis of appendiceal mucinous neoplasms is challenging, and there are few reports regarding the endosonographic characteristics of these neoplasms. To provide a retrospective assessment of the imaging features of appendiceal mucinous neoplasms using endoscopic ultrasound (EUS) by curved linear-array echoendoscope. A database of all patients with appendiceal mucinous neoplasms who had received EUS examination at our hospital between January 2018 and July 2023 was retrospectively analyzed. The EUS characteristics and patients' clinical data were reviewed. Twenty-two patients were included in the study. The linear-array echoendoscope successfully reached the ileocecal region in every patient. In the endoscopic view, we could observe the protrusion in the appendiceal orifice in all patients. A volcano sign was observed in two patients, and an atypical volcano sign was seen in two patients. EUS showed that all 22 lesions were submucosal cystic hypoechoic lesions with clear boundaries. No wall nodules were observed, but an onion-peeling sign was observed in 17 cases. Linear-array echoendoscope is safe to reach the ileocecal region under the guidance of EUS. Image features on endoscopic and echoendosonograhic views could be used to diagnose appendiceal mucinous neoplasms.

Non-inflamed appendix with LAMN causing closed-loop small bowel obstruction

Introduction: Low grade appendiceal mucinous neoplasms are generally encountered incidentally in appendicectomies for suspected appendicitis. This case is a documentation of a rare occurrence of LAMN presenting with small bowel obstruction. Case Report: An 83-year-old male presented to the Emergency Department with a three day history of nausea, vomiting, and obstipation and profoundly dehydrated. Computed tomography revealed a high grade small bowel obstruction with 2 transition points in the right iliac fossa, concerning for closed loop obstruction, necessitating an urgent laparotomy. Conclusion: While acute appendicitis is a common cause of emergency abdominal pathology, when coupled with small bowel obstruction, a neoplastic cause should be considered as part of the differential diagnosis.

Long term survival outcomes of surgery combined with hyperthermic intraperitoneal chemotherapy for perforated low-grade appendiceal mucinous neoplasms: Amulticenter retrospective study.

Low-grade appendiceal mucinous neoplasms (LAMN) are very rare, accounting for approximately 0.2%-0.5% of gastrointestinal tumors. We conducted a multicenter retrospective study to explore the impact of different surgical procedures combined with HIPEC on the short-term outcomes and long-term survival of patients. We retrospectively analyzed the clinicopathological data of 91 LAMN perforation patients from 9 teaching hospitals over a 10-year period, and divided them into HIPEC group and non-HIPEC group based on whether or not underwent HIPEC. Of the 91 patients with LAMN, 52 were in the HIPEC group and 39 in the non-HIPEC group. The Kaplan-Meier method predicted that 52 patients in the HIPEC group had 5- and 10-year overall survival rates of 82.7% and 76.9%, respectively, compared with predicted survival rates of 51.3% and 46.2% for the 39 patients in the non-HIPEC group, with a statistically significant difference between the two groups (χ2=10.622, p=0.001; χ2=10.995, p=0.001). Compared to the 5-year and 10-year relapse-free survival rates of 75.0% and 65.4% in the HIPEC group, respectively, the 5-year and 10-year relapse-free survival rates of 48.7% and 46.2% in the non-HIPEC group were significant different between the two outcomes (χ2=8.063, p=0.005; χ2=6.775, p=0.009). The incidence of postoperative electrolyte disturbances and hypoalbuminemia was significantly higher in the HIPEC group than in the non-HIPEC group (p=0.023; p=0.044). This study shows that surgery combined with HIPEC can significantly improve 5-year and 10-year overall survival rates and relapse-free survival rates of LAMN perforation patients, without affecting their short-term clinical outcomes.

Occult appendix pathology in patients undergoing colorectal cancer resection and prophylactic appendectomy.

The risk-benefit balance of prophylactic appendectomy in patients undergoing left colorectal cancer resection is unclear. The aim of this report is to assess the proportion of histologically abnormal appendices in patients undergoing colorectal cancer resection in a unit where standard of care is appendectomy, with consent, when left-sided resection is performed. A retrospective study on a prospectively collected database was conducted in a single tertiary-care center. Overall, 717 consecutive patients undergoing colorectal cancer resection between January 2015 and June 2021 were analyzed. The primary outcome was the proportion of histologically abnormal appendix specimens at prophylactic appendectomy. The secondary outcome was complications from prophylactic appendectomy. Overall, 576/717 (80%) patients had appendectomy at colorectal cancer surgery. In total, 234/576 (41%) had a right-/extended-right hemicolectomy or subtotal colectomy which incorporates appendectomy, and 342/576 (59%) had left-sided resection (left-hemicolectomy, anterior resection or abdominoperineal excision) with prophylactic appendectomy. At definitive histology, 534/576 (92.7%) had a normal appendix. The remaining 42/576 (7.3%) showed abnormal findings, including: 14/576 (2.4%) inflammatory appendix pathology, 2/576 (0.3%) endometriosis, 8/576 (1.4%) hyperplastic polyp, and 18/576 (3.1%) appendix tumors, which encompassed six low-grade appendiceal mucinous neoplasms (LAMNs), three carcinoids, and nine serrated polyps. In the 342 patients who had prophylactic appendectomy, 10 (2.9%) had a neoplasm (two LAMN, three carcinoids, and five serrated polyps). There were no complications attributable to appendectomy. Occult appendix pathology in patients undergoing colorectal cancer resection is uncommon when prophylactic appendectomy was performed. However, approximately 3% of patients had a synchronous appendix neoplasm.

Appendiceal Mucinous Incidental Neoplasm a Rare Case Report and Literature Review

Mucinous appendiceal tumors consist of mucinous adenocarcinoma, low-grade appendiceal mucinous neoplasm, and high-grade appendiceal mucinous neoplasm. The incidence of non-mucinous adenocarcinomas is reduced. The most recent edition of the World Health Organization classification and recent consensus guidelines will enable the consistent application of agreed nomenclature. Not only is precise diagnosis essential for effective patient management, but it also facilitates the comparison of results across centers and tumor registries. The most prevalent benign adenoma in the appendix is serrated. It is imperative to differentiate these conditions from low-grade appendiceal mucinous neoplasms, as the latter can also resemble harmless ailments. Adenocarcinomas of the goblet cells are a rare subtype of appendiceal neoplasm. While appendiceal neoplasms are uncommon, they are not entirely so, and even the most seasoned pathologists may find them difficult to diagnose. In addition, appendiceal neoplasia classification and terminology have been subjects of contention for decades. Nonmucinous appendiceal neoplasms are less prevalent than mucinous tumors, and their association with other appendiceal neoplasm subtypes remains uncertain. A literature review of appendiceal mucinous neoplasms identified during laparoscopic appendicectomies is presented here.

Case Report of an Appendiceal Mucinous Neoplasm: A Rare Etiology for Appendicitis

An appendiceal mucinous neoplasm is a rare condition with a clinical picture that can resemble appendicitis. Published reports have documented an incidence of 0.07-0.3% of all appendicectomies. The ubiquitous use of computerized tomography scans has helped plan surgical strategies as these patients may often require a right hemicolectomy in order to ascertain oncological clearance. This helps the clinician to avoid the complication of pseudomyxoma peritonei with its attendant increased mortality. In this case report the presence of a normal appendix base allowed for a laparoscopic intervention without having to resect the right hemi-colon. All published case reports to date have documented the involvement of the entire appendix. This case report is unique in the sparing of the proximal appendix.

Factors associated with stoma closure after cytoreductive surgery

BackgroundThe rate of stoma closure after cytoreductive surgery (CRS) ​± ​hypethermic intraperitoneal chemotherapy (HIPEC) is reportedly low. This study aimed to assess predictors of stoma reversal. MethodsWe retrospectively analyzed all patients who underwent CRS with temporary ostomy at our center between 2009 and 2021, and compared reversed versus non-reversed patients. ResultsOut of 625 CRS, 72 (11.5%) patients were included (median age 62 years, 65% female, 75% with HIPEC): 53 (74%) achieved stoma closure. Reversed patients had less high grade tumors, more appendiceal mucinous neoplasms, less ovarian primaries, and more loop ileostomies. The most common reason for non-reversal was disease progression or death (14 cases, 74%). At multivariate analysis, low/intermediate grade tumor differentiation was associated with higher stoma closure rate. ConclusionIn our study, 74% of patients achieved stoma closure after CRS with temporary ostomy. The strongest predictor of stoma closure was a low/intermediate grade tumor.

Mucocele of the Anorectal Pouch: Mucinous Cystic Neoplasm with Low-Grade Dysplasia Simulating Low- Grade Appendiceal Mucinous Neoplasm (LAMN)

Abstract Introduction/Objective We present the second case of colonic mucocele with dysplasia. To date, only five cases of colonic mucocele have been reported, all in the setting of a pouch or bypass, with only one of them showing dysplasia. The exceptional rarity of the lesion provides unique insight into etiology of mucocele. Methods/Case Report A 44-year-old male with complex surgical history including pull-through procedure for imperforate anus at birth, and later proctectomy with end colostomy due to poor anorectal function, presented with worsening low back pain radiating down to his left leg. An abdominal CT scan revealed a large pelvic cyst, causing compressive neuropathy. Multilocular cystic mass (17.5 cm) was resected, which was partially filled with mucinous material. Mucin was not seen on the cyst surface. On microscopic examination, the cyst was largely denuded however was partially lined by markedly attenuated ano-rectal type mucosa and focally by dysplastic glandular epithelium. Similar to LAMN, pools of acellular mucin dissecting stromal tissues were noted, associated with degenerative changes, calcifications and fibrosis. No invasive carcinoma or high-grade dysplasia was seen. Given the lack of extra- cystic mucin or evidence of overt malignancy, it was reported as mucinous cystic neoplasm with uncertain malignant potential. The patient has been followed for 16 months without evidence of recurrence or peritoneal disease. Results (if a Case Study enter NA) NA Conclusion Extended stasis within a bowel segment appear to contribute to the development of mucoceles. The blind-ended anatomy of the appendix renders it highly susceptible to this phenomenon, explaining the relatively high incidence of LAMN. Conversely, such prolonged stasis rarely occurs elsewhere in colon unless a pouch or bypassed segment is surgically created, particularly placing patients with a complex surgical history at the highest risk. Therefore, close follow-up is indicated in this patient group to screen for mucocele that may progress to develop dysplasia and mucinous neoplasm.

Analysis of the characteristics and outcomes of patients with pseudomyxoma peritonei of appendiceal origin treated with curative-intent surgery

BackgroundThere are no previous studies on pseudomyxoma peritonei regarding the details of surgical procedures included in cytoreductive surgery and quantitative evaluation for peritoneal metastases by region in the abdominal cavity. This study aimed to describe the characteristics and procedural details involved in cytoreductive surgery, and survival outcomes of patients with pseudomyxoma peritonei originating from appendiceal mucinous neoplasm, and identify differences in the difficulty of cytoreductive surgery based on tumor location. MethodsPatient characteristics and survival outcomes were studied through a retrospective review. The complete cytoreduction rate (i), the 5-year survival rate for patients with complete cytoreduction (ii), and an index as a complement (i × ii × 100) were described for patients who had tumors larger than 50 mm in one of the 13 regions of the abdominal cavity. ResultsA total of 989 patients were treated with curative-intent cytoreductive surgery. The median peritoneal cancer index was 18 (interquartile range, 6–29), with complete cytoreduction achieved in 702 patients (71%); the major complication rate was 17%. The median overall survival was 92.9 months, compared to 53.8 months for patients who underwent total gastrectomy and 30.4 months for those who underwent total colectomy. In the 13 abdominal regions, the index scores indicating cytoreduction difficulty were categorized into three risk groups: upper and mid-abdominal (>20), lateral abdominal (10–20), and small bowel (<10). ConclusionsCytoreductive surgery offered favorable survival outcomes, even in cases involving total gastrectomy. The difficulty of achieving complete cytoreduction varied across abdominal regions and was classified into three levels.

Appendiceal Mucinous Neoplasm in a Young Male- A Case Study

Appendiceal Mucinous Neoplasm in a Young Male- A Case Study

Incidence of occult appendiceal neoplasm in patients over 40 years with acute appendicitis: A single-institution review.

To investigate the incidence of occult appendiceal neoplasm in patients aged 40 years and over who underwent appendicectomy for appendicitis. The clinical coding electronic database was used to identify patients aged 40 years and over who were diagnosed with appendicitis from September 2010 to September 2022. Patients were included if they were managed operatively. Retrospective cohort study. Modified Monash category 3 (large rural town). Patients aged 40 years and over undergoing appendicectomy for appendicitis. Incidence of appendiceal neoplasm within appendicectomy specimen. A total of 279 patients aged 40 years and over underwent appendicectomy, with a median age of 53 years (range 40-95). Nineteen patients (7%) were found to have a primary neoplastic lesion within the appendix: seven neuroendocrine neoplasms (37%), six sessile serrated lesions (32%), two colonic-type adenocarcinoma (11%), two goblet cell adenocarcinoma (11%) and two appendiceal mucinous neoplasms (11%). Additionally, one patient had a metastatic adenocarcinoma of pancreaticobiliary aetiology. Occult appendiceal neoplasm was higher than reported in the literature in our cohort. This would support appendicectomy as the treatment of choice for patients aged 40 years and over with acute appendicitis and caution against nonoperative management in this demographic.

Low-Grade Appendiceal Mucinous Neoplasm: What Is the Best Treatment?

Low-grade appendiceal mucinous neoplasm (LAMN) is an uncommon tumor of the appendix that is usually diagnosed incidentally after surgery. Although LAMN may be asymptomatic, it can rupture and seed mucin and neoplastic epithelium into the peritoneum, causing pseudomyxoma peritonei (PMP). Data from 53 patients were retrospectively analyzed. Age, sex, tumor size, margin status, peritoneal carcinomatosis index, surgical procedures, postoperative results with histologic diagnosis, T stage, recurrence, and mortality of the patients were evaluated. Appendectomy was performed in 37 patients, right hemicolectomy in nine patients, cytoreductive surgery in one patient, and cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in six patients. Recurrence occurred in four patients. Of the patients who developed recurrence, one patient had stage T4a disease, and the other three patients had T4b disease (p<0.001). Eighteen patients had acellular mucin in the serosa and four of these patients developed recurrence (p=0.004). Twelve patients had appendix perforation, and three of these patients had PMP on exploration (p<0.001). The mean survival time was 93.3 months in patients without recurrence and 32 months in patients with recurrence (p=0.021). Low-grade appendiceal mucinous neoplasms are rare appendiceal tumors. The appropriate management of this tumor is controversial. T stage, appendix perforation, presence of acellular mucin on the serosa, and surgical margins are risk factors for the development of PMP. Appendectomy is considered sufficient when there are no risk factors for Tis (LAMN) and T3 disease. Right hemicolectomy may be sufficient if there are no risk factors for T4a disease, but cytoreductive surgery and hyperthermic intraperitoneal chemotherapy seem to be the most appropriate treatments in the presence of the stated risk factors for T4b disease.

The value of ultrasound combined with CT in identifying early low-grade appendiceal mucinous neoplasm and appendicitis.

The aim of this study is to investigate the value of ultrasound combined with computed tomography (CT) in identifying early low-grade appendiceal mucinous neoplasm and appendicitis. Patients with early low-grade appendiceal mucinous neoplasm and appendicitis from September 2017 to September 2021, including 40 patients with low-grade appendiceal mucinous neoplasm and 40 patients with appendicitis, were collected in this study. Clinical data as well as ultrasound and CT findings of all patients were retrospectively analyzed. Univariate and multivariate logistic regression analyses were applied to establish the ultrasound model, the CT model, and the combined model. The nomogram showed that specific characteristics of CT were dilated appendiceal diameter and clear surrounding fat space in the low-grade appendiceal mucinous neoplasm and that specific characteristics of ultrasound were thin or clear layer appendix wall and flocculent echo in the appendix cavity. These four features were used to construct a nomogram for predicting early low-grade appendiceal mucinous neoplasm, and the area under the curve value was 0.839. Ultrasound combined with CT for diagnosis of early low-grade appendiceal mucinous neoplasm has a significant value; when found significantly dilated appendix in the lower right abdomen, with thin wall, wall calcification, clear surrounding fat space, and progressive enhancement, especially non-specific symptoms similar to appendicitis, the physician should timely consider the possibility of low-grade appendiceal mucinous neoplasm.

How to manage localized low-grade appendiceal mucinous neoplasm?

How to manage localized low-grade appendiceal mucinous neoplasm?

Contrast-enhanced ultrasonography findings of LAMNs with peritoneal and splenic metastases: a case report and literature review.

Low-grade appendiceal mucinous neoplasms (LAMNs) are rare appendiceal tumors that are primarily diagnosed using computed tomography(CT) enhancement and magnetic resonance imaging (MRI). Herein, we report the sonographic features, especially for contrast-enhanced ultrasound (CEUS), of a 70-year-old female with an unusual LAMN metastasizing to the peritoneum and spleen. The patient had a right pelvic mass 2 days prior to presentation. Two-dimensional (2D) ultrasound revealed a mixed cystic-solid mass in the right lower abdomen and spleen parenchyma; CEUS showed heterogeneous enhancement in both areas, suspected to be a mucinous mass. CT enhancement and MRI findings revealed concurrent findings. Histopathologically, LAMN lesions were confirmed in the appendix, spleen, and peritoneum of the specimens obtained during exploratory laparoscopy. No recurrences were reported at three years postoperatively. LAMN lesions may metastasize to abdominal organs, and imaging examinations are essential for diagnosis. This study presents major ultrasonography and CEUS findings for the diagnosis of LAMNs.

Subtotal and Total Colectomy as a One-Stage Surgical Treatment for Malignant Left-Sided Colonic Obstruction

Abstract Aim: We conducted this retrospective study in order to evaluate the short- and long-term results of Subtotal/Total Colectomy (STC/TC) and primary anastomosis for the treatment of occlusive left colon cancer. Methods: Data were retrospectively collected from the medical records from general surgery clinic in January 2016 to June 2022 period. The study included patients diagnosed with acute colonic occlusion produced by tumor located from the splenic flexure to the rectosigmoid junction. Results: During the study period, 40 patients who underwent STC/TC and primary anastomosis were included in the study. According to the Clavien-Dindo grades, major complication rate was 17.5%. Seven patients (17.5%) had synchronous adenocarcinoma. Adenoma was detected in 11 of 40 patients, and 18.1% of them were reported as high-grade dysplasia. Besides, incidental low grade appendiceal mucinous neoplasm was reported in one patient. Ischemia and perforation of proximal colon was found in 28 cases (70%). No patient had anastomotic leak. After one year of surgery, the average defecation was two stools per day. Three-year OS was 92.3% in stage II and 68.7% in stage III. There was no survival more than three years in stage IV patients. The three-year overall disease- free survival was 90.6%. Conclusion: Treatment of obstructive left colon cancer using STC/TC and primary anastomosis is a confident method resulting in a good bowel function. The method allows the resection of synchronous tumors. Besides, it removes the proximal colon with ischemic lesions, serosal tears and filled with stool.

Incidence of appendiceal neoplasms in appendectomy patients

BackgroundNon-operative management has been suggested as a therapy for uncomplicated appendicitis. Notwithstanding, the risk of missing an appendiceal tumor must be considered, being the surgical piece crucial to rule out neoplasms. Therefore, we aim to determine the incidence of appendiceal neoplasms in patients with acute appendicitis, tumor types and the importance of the anatomopathological study of the surgical piece.Study designRetrospective study in which we described patients who underwent emergent appendectomy with histopathological findings of appendiceal neoplasms from January 2012 to September 2018. Descriptive analysis included demographic variables, diagnostic methods, and surgical techniques.Results2993 patients diagnosed with acute appendicitis who underwent an emergency appendectomy. 64 neoplasms of the appendix were found with an incidence of 2,14%. 67.2% were women, the mean age was 46,4 years (± 19.5). The most frequent appendiceal neoplasms were neuroendocrine tumors (42,2%), followed by appendiceal mucinous neoplasms (35,9%), sessile serrated adenomas (18,8%), and adenocarcinomas (3,1%). In 89,1% of the cases, acute appendicitis was determined by imaging, and 14% of cases were suspected intraoperatively. Appendectomy was performed in 78,1% without additional procedures.ConclusionsAppendiceal tumors are rare and must be ruled out in patients with suspected acute appendicitis. The incidence of incidental neoplasms is higher in this study than in the previously reported series. This information must be included in decision-making when considering treatment options for acute appendicitis.