A retrospective clinicopathological analysis of appendiceal tumors from 3,744 appendectomies: a single-institution study

A Decade-Long Retrospective Clinicopathological Study of Appendiceal Neoplasms

INTRODUCTION

 Appendiceal neoplasms (ANs) are uncommon, representing less than 1% of all gastrointestinal tumors. They are most often discovered incidentally during appendectomies performed for suspected acute appendicitis. Recent studies have reported an increase in the incidence of AN. Our study aimed to analyze the spectrum of AN and determine the cases discovered incidentally.

MATERIAL AND METHODS

 This retrospective descriptive study was performed over 10 years, from March 2014 to March 2024, at Saveetha Medical College and Hospital in Chennai, India. Complete enumeration sampling was performed, and tumor registries were reviewed to identify all cases of AN received during the study period. The corresponding clinical and radiological data were obtained from the hospital database, whereas histopathology records were used to evaluate tumor characteristics. Descriptive statistical analysis was employed, and the spectrum of AN was analyzed.

RESULTS

 During the study period, 12 cases of AN were identified. Eleven cases (91.7%) were diagnosed from appendicectomy specimens, while one was from a right hemicolectomy specimen. Of these 12, nine cases (75%) were incidental findings. In our study, we found that there was a higher number of female cases, with nine out of twelve cases (75%) being female. Most patients presented with abdominal pain, and acute appendicitis was the most frequent preoperative diagnosis. Low-grade appendiceal mucinous neoplasm was the most common type encountered followed by other appendiceal tumors.

CONCLUSION

 The incidence of AN has increased in recent years, with most cases being found incidentally. Given the increasing rate of incidental AN, it is vital to maintain vigilance in specimen analysis including comprehensive examination and precise grossing to ensure malignancies are not overlooked.

The incidence of incidental neoplasia in pathology samples of patient who underwent appendectomy due to acute appendicitis. A single center experience: 6446 cases

PURPOSE

Appendectomy is the standard treatment of acute appendicitis. However, recent advancements have introduced medical treatment as a potential alternative. Within this context, it's important to recognize the rare occurrence of appendiceal tumors, often incidentally discovered during histopathological examination following appendectomy. Consequently, there's a concern about the possibility of overlooking appendiceal neoplasms, particularly in cases where conservative treatment for acute appendicitis is considered.

METHODS

The files of patients who underwent surgery for acute appendicitis between January 2015 and December 2023 and were diagnosed with neoplasia in their pathology reports were retrospectively registered. Demographic characteristics of the patients, laboratory and imaging features, details of the surgery performed, preoperative and intraoperative suspicion of neoplasm and data from pathology reports were collected and analyzed.

RESULTS

A total of 6446 patients were operated for acute appendicitis. Neoplasia was detected in the histopathological examination of 93 patients (1.44%). Acute appendicitis was diagnosed in 51.6% of the patients by computed tomography. Neoplasm suspicion was present in 9.7% of patients in preoperative imaging methods and in 6.5% of patients intraoperatively. Only appendectomy was performed in 94.5% of patients. The most common appendiceal neoplasm is neuroendocrine tumors (40.9%), followed by appendiceal mucinous neoplasm (29%), sessile serrated adenoma (15%), and adenocarcinoma (6.5%).

CONCLUSION

Although appendiceal neoplasms are relatively rare in proportion, they represent a significant numerical value due to the density of cases. Therefore, this information should be taken into consideration when evaluating treatment options for acute appendicitis.

Appendiceal Goblet Cell Carcinoma: Role of Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

Goblet cell carcinoma (GCC) encompasses a separate entity in appendiceal neoplasms with mixed glandular and neuro-endocrine pathological features. GCC mostly presents as an acute appendicitis duo to luminal obstruction or as an incidental finding on the surgical appendectomy specimen. In case of tumour perforation or presence of other risk factors, guidelines suggest additional treatment with a completing right hemicolectomy or cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). We report the case of a 77-year-old male with symptoms of appendicitis for which an appendectomy was performed. The appendix was ruptured during the procedure. There was an incidental finding of GCC on the pathological specimen. Because of possible tumour soiling, the patient received a prophylactic CRS-HIPEC. A literature review was performed to investigate the potential role for CRS-HIPEC as a curative treatment in patients with GCC. GCC of the appendix is an aggressive type of tumour with a high risk of peritoneal and systemic dissemination. CRS and HIPEC is a treatment option: both in a prophylactic setting and in patients with established peritoneal metastases.

Diagnostic and Therapeutic Algorithm for Appendiceal Tumors and Pseudomyxoma Peritonei: A Consensus of the Peritoneal Malignancies Oncoteam of the Italian Society of Surgical Oncology (SICO)

Aim: Pseudomyxoma peritonei (PMP) is an uncommon pathology, and its rarity causes a lack of scientific evidence, precluding the design of a prospective trial. A diagnostic and therapeutic algorithm (DTA) is necessary in order to standardize the disease treatment while balancing optimal patient management and the correct use of resources. The Consensus of the Italian Society of Surgical Oncology (SICO) Oncoteam aims at defining a diagnostic and therapeutic pathway for PMP and appendiceal primary tumors applicable in Italian healthcare. Method: The consensus panel included 10 delegated representatives of oncological referral centers for Peritoneal Surface Malignancies (PSM) affiliated to the SICO PSM Oncoteam. A list of statements regarding the DTA of patients with PMP was prepared according to recommendations based on the review of the literature and expert opinion. Results: A consensus was obtained on 33 of the 34 statements linked to the DTA; two flowcharts regarding the management of primary appendiceal cancer and peritoneal disease were approved. Conclusion: Currently, consensus has been reached on pathological classification, preoperative evaluation, cytoreductive surgery technical detail, and systemic treatment; some controversies still exist regarding the exclusion criteria for HIPEC treatment. A shared Italian model of DTA is an essential tool to ensure the appropriateness and equity of treatment for these patients.

Risk of appendiceal neoplasm after interval appendectomy for complicated appendicitis: A systematic review and meta-analysis

BACKGROUND

Non-operative management is often the treatment of choice in cases of complicated appendicitis and routine interval appendectomy is not usually recommended. Actually, recent studies show an alarming number of appendiceal neoplasms following interval appendectomy. The aim of this study is to evaluate the prevalence of appendiceal neoplasms and their histological types after interval appendectomy for complicated appendicitis in adults.

METHODS

A comprehensive literature search of the PubMed, Scopus and Web of Science databases was conducted according to the PRISMA statement. Studies reporting appendiceal neoplasm rates after interval appendectomy and histopathological characteristics were included. The most recent World Health Organization (WHO) classification of malignant tumours was considered. A pooled prevalence analysis for both prevalence and pathology was performed.

RESULTS

A total of eight studies was included: seven retrospective series and one randomized controlled trial. The pooled prevalence of neoplasms after interval appendectomy was 11% (95% CI 7-15; I² = 37.5%, p = 0.13). Appendiceal mucinous neoplasms occurred in 43% (95% CI 19-68), adenocarcinoma in 29% (95% CI 6-51), appendiceal neuroendocrine neoplasm in 21% (95% CI 6-36), globet cell carcinoma in 13% (95% CI -2-28), adenoma or serrated lesions in 20% (95% CI -0-41) of cases.

CONCLUSION

The risk of appendiceal neoplasm in patients treated with interval appendectomy for complicated appendicitis is 11%; mucinous neoplasm is the most common histopathological type. Further studies should investigate this association in order to clarify the biological pathway and clinical implications.

Rising incidence of appendiceal neoplasms over time: Does pathological handling of appendectomy specimens play a role?

BACKGROUND

Appendectomy is the most common emergent surgical procedure. Primary appendiceal neoplasms are rare entities that are usually detected incidentally in less than 2% of all appendectomies. The increase in the incidence rates of appendiceal neoplasms over time raises the question whether there is an actual change in the disease occurrence or is it a matter of increased recognition and reporting of what would have been previously missed and undiagnosed.

OBJECTIVES

In our study, we aimed to review the archived tissue specimens of patients who were diagnosed with appendiceal neoplasms during the past decade at our institution and compare our clinical experience with published data to identify possible reasons that contribute to the increase in incidence rates of such neoplasms over the past few years.

METHODS

Using a pathological database of surgical specimens from patients who underwent appendectomies between January 01, 2010 and September 30, 2020 at a large academic medical center, a single-center retrospective cohort analysis was performed, and medical charts of patients were reviewed.

RESULTS

Of the total 1568 patients included, 102 (6.5%) had appendiceal neoplasms divided between primary (79.4%) and secondary/metastatic (20.6%) neoplasms. Annual incidence of appendiceal neoplasms over the past 10 years in our institution demonstrated an increasing trend from 5.6% in 2010 to 12.7% in 2020, which we hypothesize might be attributed to submitting more representative sections of the appendix for pathological examination than we had previously. Our results also showed that 2.8% of patients initially presenting with a typical clinical picture of acute appendicitis had appendiceal neoplasms as a truly incidental finding, while 20.3% of patients who underwent elective appendectomies for a suspicious appendiceal mass were found to be neoplastic. Interestingly, among the 80 cases of epithelial neoplasms, more non-carcinoid neoplasms were detected than carcinoid tumors.

CONCLUSION

Based on our results and what has been published recently, we confirm an additional increase in incidental appendiceal neoplasms found in appendectomies performed for a clinical picture of acute appendicitis, which may be related to more thorough specimen assessment. Whether this is clinically impactful remains to be determined. However, these data support a modification in the way appendectomy specimens are handled in pathology labs post-operatively.

Predictors of Progression of Appendiceal Mucinous Neoplasm to Pseudomyxoma Peritonei

Appendiceal mucinous neoplasm (AMN) can present with a spectrum of disease. Predicting factors in development of pseudomyxoma peritonei (PMP) from AMN could aid in management and treatment. The aim of this study was to determine factors predictive of PMP from AMN. This was a retrospective multicenter study of all patients diagnosed with AMN from 2006-2017. Diagnosis of PMP was compared by (1) patient demographics, (2) tumor characteristics, and (3) surgery. Secondary end points were disease-specific survival (DSS) and overall survival (OS).One-hundred thirty-eight patients with AMN were identified. Thirty-six patients (26.1%) had a ruptured appendix at presentation, and 12 patients (8.7%) were diagnosed with PMP during the study period. Eight patients presented with PMP at the time of surgery. No demographic factors were predictive of PMP. Operative approach and extent of initial resection did not correlate with PMP. Tumor rupture at presentation was the only factor associated with PMP, though only 14% of patients who presented with simple rupture eventually progressed to PMP.OS was not different between those who were diagnosed with PMP and those who were not. DSS was significantly lower for the group diagnosed with PMP (P = .007). Tumor rupture at presentation did not influence OS or DSS. The only factor found to be significantly associated with PMP was tumor rupture at presentation. Diagnosis of PMP did not affect OS but did lead to decreased DSS.In conclusion, though a majority of patients who presented with rupture did not go on to develop PMP, tumor rupture at presentation was the only factor significantly associated with PMP. Diagnosis of PMP did not affect OS at 5 years. In patients with AMN who present with a ruptured appendix on final pathology, we recommended continued surveillance, though overall risk of PMP is relatively low.

National trends in the presentation of surgically resected appendiceal adenocarcinoma over a decade

BACKGROUND

Rates of nonoperative management of acute appendicitis and appendiceal adenocarcinoma have increased over a decade, but the presentation and outcomes of appendiceal adenocarcinoma over this period is not well-characterized.

METHODS

Patients with surgically resected Stage I-III appendiceal adenocarcinoma were identified from the 2006 to 2015 National Cancer Data Base and classified into two cohorts, 2006-2010 and 2011-2015, based on year of diagnosis. Three-year overall survival (OS) was analyzed using Cox proportional hazards regression and Kaplan-Meier survival estimates.

RESULTS

Of 4233 patients, 1369 (32.3%) and 2864 (67.7%) were diagnosed in 2006-2010 and 2011-2015, respectively. Following multivariable analysis, patients in 2011-2015 were more likely to be <40 years of age (6.4% vs. 4.7%, odds ratio [OR] 1.53, p .015), present with pT4 tumors (40.2% vs. 34.4%, OR 1.46, p .004), and undergo hyperthermic intraperitoneal chemotherapy (4.4% vs. 2.4%, OR 1.97, p .001). Comparing patients diagnosed in 2011-2015 to 2006-2010, adjusted 3-year OS was no different among all patients (81.1% vs. 79%, p .778).

CONCLUSIONS

There has been an increase in the proportion of patients with pT4 appendix tumors over time, primarily among older (≥60 years) patients. Even so, these shifts in presentation have not resulted in differences in survival outcomes.

Open versus laparoscopic surgery for primary appendiceal tumors: a large multicenter retrospective propensity score-matched cohort study in Japan

BACKGROUND

The feasibility of laparoscopic surgery for primary appendiceal tumors compared to that of open surgery has not been demonstrated to date because primary appendiceal tumors are rare. This study aimed to compare the long-term outcomes between laparoscopic and open surgeries for primary appendiceal tumors.

METHODS

In this multicenter retrospective cohort study, the data of patients who had been histologically diagnosed with primary appendiceal tumors at 43 tertiary hospitals in Japan between 2000 and 2017 were analyzed. In total, 922 patients were assessed, and 679 cases were eligible for analysis. Using propensity scores, the baseline characteristics were matched for 114 open surgery cases and 114 laparoscopic surgery cases. The primary endpoints were recurrence-free survival (excluding patients with stage IV disease with distant metastasis) and overall survival.

RESULTS

The rate of conversion from laparoscopic to open surgery was 1.5%. The 5-year recurrence-free survival rates were 80.4% (95% confidence interval: 71.0-89.7) and 78.2% (95% confidence interval: 69.0-87.3) in the laparoscopic and open surgery groups, respectively, with no significant difference (p = 0.57). No significant difference was observed in the 5-year overall survival rates between the laparoscopic [83.5% (95% confidence interval: 74.4-92.7)] and open surgery [72.7% (95% confidence interval: 62.3-83.0); p = 0.09] groups. In multivariate analysis, laparoscopic surgery was not identified as an independent prognostic factor for overall survival [hazard ratio: 0.49 (95% confidence interval: 0.23-1.06), p = 0.0707].

CONCLUSIONS

Laparoscopic surgery is comparable to open surgery and can be considered a treatment option for primary appendiceal tumors.

Is interval appendectomy really needed? A closer look at neoplasm rates in adult patients undergoing interval appendectomy after complicated appendicitis

BACKGROUND

The treatment algorithm for appendicitis is evolving, with recent interest in non-operative management. However, the safety of non-operative management for patients with complicated appendicitis has been questioned due to concern for increased risk of occult appendiceal neoplasm in this patient population. Our study aims to determine the rate of neoplasms discovered during interval appendectomy for patients with complicated appendicitis and determine the necessity of interval appendectomy.

METHODS

A retrospective chart review was conducted on interval appendectomies performed in adult patients for complicated appendicitis at our institution over a 9-year period. Interval appendectomy was defined as appendectomy delayed from initial presentation with appendicitis. Complicated appendicitis was defined as perforation, phlegmon, and/or abscess as seen on computed tomography at time of presentation.

RESULTS

We identified 402 patients who underwent interval appendectomy for complicated appendicitis. A total of 36 appendiceal neoplasms were discovered on final pathology with an overall neoplasm rate of 9%. Patients with an appendiceal neoplasm were significantly older (56.6 years vs 45.1 years, p < 0.01). No patients under the age of 30 had a neoplasm. The rate of appendiceal neoplasms in patients 30 years and older was 11%. The rate for patients 50 years and older was 16%. For patients 80 years and older, the rate of appendiceal neoplasm was 43%.

CONCLUSION

The risk of occult appendiceal neoplasm is low in patients under the age of 30; however, there was an 11% rate of appendiceal neoplasm in patients 30 years and older. The risk increases with increased age, with a 16% risk in patients 50 years and older. Given these findings, we recommend consideration of interval appendectomy in all patients 30 years and older with complicated appendicitis.

Preoperative Factors Associated with Appendiceal Tumors in Nonelective Appendectomy

Background: The rates of incidental appendiceal neoplasms after appendectomy performed for acute appendicitis is <2%. To date, no large studies have investigated the preoperative risk factors or imaging findings associated with incidental appendiceal tumors that present as appendicitis. Our study aims to identify preoperative factors that are associated with an increased risk of appendiceal tumors in patients who present with signs and symptoms of acute appendicitis. Materials and Methods: Using the targeted appendectomy American College of Surgeons National Surgical Quality Improvement Program database, we identified patients who underwent nonelective appendectomy for acute appendicitis in 2016. Patients with final pathology consistent with a tumor were compared with those with only appendicitis. A nonmatched case/control method was used to pull a random sample from the appendicitis cohort using a 1:4 ratio (tumor: acute appendicitis) to obtain adequate power for comparison. Preoperative patient variables and imaging findings were investigated using stepwise logistic regression to identify variables associated with appendiceal tumor. Results: Following multivariate analysis, preoperative imaging read of "indeterminate" and "not consistent with appendicitis," female gender, increased age, and lower preoperative white blood cell (WBC) count were significant predictors of tumor causing symptoms of appendicitis. The odds of having tumor pathology were significantly increased in patients with preoperative imaging of "indeterminate" and "not consistent with appendicitis." The odds of having tumor pathology were 82% higher for females than for males, increased by 2% for every 1-year increase in age, and increased by 3% for every one-unit decrease in WBC count. Conclusion: While incidental appendiceal tumors can present as acute appendicitis, 3 patient variables and one imaging finding were identified that may increase suspicion for appendiceal tumors. Consideration should be given to patients with these associated risk factors for additional preoperative consultation in addition to the potential for intraoperative pathology consultation.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Increased Risk of Neoplasms in Adult Patients Undergoing Interval Appendectomy

PURPOSE

The low rate of recurrent appendicitis after initial nonsurgical management of complicated appendicitis supports the recently implemented strategy of omitting routine interval appendectomy. However, several reports have suggested an increased incidence rate of neoplasms in these patients. We aimed to identify the risk of neoplasms in the population undergoing interval appendectomy.

METHODS

This study retrospectively analyzed consecutive cases of appendicitis that were treated surgically between January 2014 and December 2018 at a single tertiary referral center. Patients were divided into 2 groups depending on whether they underwent immediate or interval appendectomy. Demographics and perioperative clinical and pathologic parameters were analyzed.

RESULTS

All 2,013 adults included in the study underwent surgical treatment because of an initial diagnosis of acute appendicitis. Of these, 5.5% (111 of 2,013) underwent interval appendectomy. Appendiceal neoplasm was identified on pathologic analysis in 36 cases (1.8%). The incidence of neoplasm in the interval group was 12.6% (14 of 111), which was significantly higher than that of the immediate group (1.2% [22 of 1,902], P < 0.001).

CONCLUSION

The incidence rate of neoplasms was significantly higher in patients undergoing interval appendectomy. These findings should be considered when choosing treatment options after successful nonsurgical management of complicated appendicitis.

Risk of Appendiceal Neoplasm in Periappendicular Abscess in Patients Treated With Interval Appendectomy vs Follow-up With Magnetic Resonance Imaging: 1-Year Outcomes of the Peri-Appendicitis Acuta Randomized Clinical Trial

Importance

The step after conservative treatment of periappendicular abscess arouses controversy, ranging from recommendations to abandon interval appendectomy based on low recurrence rates of the precipitating diagnosis to performing routine interval appendectomy owing to novel findings of increased neoplasm risk at interval appendectomy. To our knowledge, there are no randomized clinical trials with sufficient patient numbers comparing these treatments.

Objective

To compare interval appendectomy and follow-up with magnetic resonance imaging after initial successful nonoperative treatment of periappendicular abscess.

Design, Setting, and Participants

The Peri-Appendicitis Acuta randomized clinical trial was a multicenter, noninferiority trial conducted in 5 hospitals in Finland. All patients between age 18 and 60 years with periappendicular abscess diagnosed by computed tomography and successful initial nonoperative treatment from January 2013 to April 2016 were included. Data analysis occurred from April 2016 to September 2017.

Interventions

Patients were randomized either to interval appendectomy or follow-up with magnetic resonance imaging; all patients underwent colonoscopy.

Main Outcomes and Measures

The primary end point was treatment success, defined as an absence of postoperative morbidity in the appendectomy group and appendicitis recurrence in the follow-up group. Secondary predefined end points included neoplasm incidence, inflammatory bowel disease, length of hospital stay, and days of sick leave.

Results

A total of 60 patients were included (36 men [60%]; median [interquartile range] age: interval appendectomy group, 49 [18-60] years; follow-up group, 47 [22-61] years). An interim analysis in April 2016 showed a high rate of neoplasm (10 of 60 [17%]), with all neoplasms in patients older than 40 years. The trial was prematurely terminated owing to ethical concerns. Two more neoplasms were diagnosed after study termination, resulting in an overall neoplasm incidence of 20% (12 of 60). On study termination, the overall morbidity rate of interval appendectomy was 10% (3 of 30), and 10 of the patients in the follow-up group (33%) had undergone appendectomy.

Conclusions and Relevance

The neoplasm rate after periappendicular abscess in this small study population was high, especially in patients older than 40 years. If this considerable rate of neoplasms after periappendicular abscess is validated by future studies, it would argue for routine interval appendectomy in this setting.

Trial Registration

ClinicalTrials.gov identifier: NCT03013686.

Surveillance of Low-Grade Appendiceal Mucinous Neoplasms With Peritoneal Metastases After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Are 5 Years Enough? A Multisite Experience

BACKGROUND

Low-grade appendiceal mucinous neoplasms (LAMNs) are tumors that often present with widespread mucin in the peritoneal cavity (pseudomyxoma peritonei [PMP]). Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are effective treatment, but no published recommendations exist regarding surveillance.

METHODS

Data from prospective databases of patients who underwent CRS-HIPEC from 2001 to 2017 at two high-volume institutions were retrospectively analyzed. Patients who underwent complete CRS-HIPEC for PMP secondary to LAMN were included in the analysis. Pathologic examination confirmed the diagnosis of LAMN. Cases of mucinous adenocarcinomas and neuroendocrine tumors (goblet cell carcinoids) were excluded.

RESULTS

The study enrolled 156 patients. The median peritoneal cancer index (PCI) was 18 (interquartile range IQR1-3, 12-23), and 125 patients (80.1%) had a CC0 cytoreduction. According to American Joint Committee on Cancer (AJCC) grading, 152 patients (97.4%) presented with acellular mucin or G1 implants, 2 patients (1.3%) presented with G2 disease, and 2 patients (1.3%) presented with G3 disease. During the follow-up period (median, 45 months; IQR1-3 23-76 months), 23 patients (14.7%) experienced recurrence. All the recurrences were peritoneal and occurred within 5 years. The 1-, 3-, and 5-year disease-free survival (DFS) rates were respectively 95.5%, 83.4%, and 78.3%. Univariate Cox regression analysis showed that higher PCI scores (p < 0.001), a CC1 cytoreduction (p = 0.005), and higher preoperative levels of carcinoembryonic antigen (CEA) (p = 0.012) and CA-125 (p = 0.032) correlated with a shorter DFS. Only higher PCI scores independently predicted earlier recurrences (p < 0.001).

CONCLUSION

Most patients had recurrence within 3 years after CRS-HIPEC, and none after 5 years. High PCI was the only independently significant variable. The study findings support intensive surveillance (every 3-6 months) with tumor markers and imaging methods during the first 3 years, and annual surveillance thereafter, with follow-up assessment after 5 years yielding limited benefit.

Appendiceal neoplasm risk associated with complicated acute appendicitis-a population based study

PURPOSE

Appendiceal tumors are rare, but high neoplasm rates have been reported at interval appendectomy after periappendicular abscess. Non-operative management of uncomplicated acute appendicitis has shown promising results. The data on appendiceal tumor incidence and presentation among acute appendicitis patients is limited, especially in patient cohorts differentiating between uncomplicated and complicated acute appendicitis. Objective was to assess appendiceal tumor incidence and tumor association to appendicitis in patients with uncomplicated and complicated acute appendicitis.

METHODS

This nationwide population-based registry study was conducted from 2007 to 2013. The Finnish Cancer Registry and the National Institute for Health Registry were used to combine data on all appendiceal tumors and acute appendicitis diagnosis with medical reports evaluated at eight study hospitals.

RESULTS

Altogether, 840 appendiceal tumors were identified, and out of these, 504 patient reports were reviewed, including 472 patients in this study. Tumor was diagnosed at appendectomy for suspected acute appendicitis in 276 patients (58%). In the whole study, histologically acute appendicitis and tumor were both present in 53% (n = 250), and out of these, 41% (n = 102) were complicated and 59% (n = 148) uncomplicated acute appendicitis. The associated tumor risk was significantly higher in complicated acute appendicitis compared with uncomplicated cases (3.24% vs. 0.87%, p < 0.001). Overall tumor prevalence among acute appendicitis patients was 1.24%.

CONCLUSIONS

Appendiceal tumor prevalence in acute appendicitis was low. Tumor risk was significantly higher in complicated acute appendicitis compared with uncomplicated acute appendicitis. The risk of missed appendiceal tumors related to antibiotic therapy of uncomplicated acute appendicitis is very low.

Analysis of Appendiceal Neoplasms on 3544 Appendectomy Specimens for Acute Appendicitis: Retrospective Cohort Study of a Single Institution

Background

Appendiceal neoplasms are rare and generally determined in appendectomy specimens for acute appendicitis. Depending on a tumor’s histopathology and size, appendectomy or right hemicolectomy are the surgical treatment options. Adenocarcinomas, mucinous neoplasms, goblet cell carcinoids and neuroendocrine tumors are the types of the primary appendiceal neoplasm histopathology. In this study, we aimed to determine the incidence of appendiceal neoplasms in an acute appendicitis cohort. Also, histopathological distributions, demographic data, preoperative radiological diagnosis, and intraoperative findings were revealed for analysis, retrospectively.

Material/Methods

Between October 2011 and September 2017, 3554 appendectomies were performed for acute appendicitis in Bezmialem University Hospital, Istanbul Turkey. The medical records of these consecutive 3554 patients were evaluated retrospectively. After the histopathological analysis of the appendectomy specimens, a total of 28 patients were detected as having appendiceal neoplasm including appendiceal adenocarcinoma, low grade mucinous neoplasia, and appendiceal neuroendocrine tumors.

Results

Appendiceal neoplasms were determined in 28 out of 3554 acute appendicitis patients with an incidence of 0.78%. According to the histopathological types, 3 of the cases (10.7%) were appendiceal adenocarcinoma, 8 of the cases (28.5%) were low grade mucinous neoplasia, and 17 of the cases (60.8%) were neuroendocrine tumors. The overall incidence of the appendiceal neuroendocrine tumors was 0.48%.

Conclusions

The information obtained from our study suggests that pathological examination of the specimen may not be necessary if there is no doubt according to preoperative radiological diagnosis and/or intraoperative findings of the surgeon.

Single-center analysis of appendiceal neoplasms

The purpose of the present study was to evaluate the recent trend of diagnosing appendiceal diseases through the analysis of appendectomy materials, stressing the importance of their pathological examination. A clinicopathological assessment of patients undergoing an appendectomy was conducted, based on the pathological examination of resected appendiceal lesions. Using a pathological database of surgical specimens from patients who underwent an appendectomy between March 2002 and September 2014, a retrospective, single-center analysis was performed. Among the 803 patients identified, 752 with appendiceal disease were selected for clinicopathological analysis. The diagnosis was inflammation (i.e. appendicitis) in 97.7% (n=735) and appendiceal neoplasm in 2.3% (n=17) of the patients. The most frequent type of appendiceal neoplasm was an intramucosal neoplasm (23.5%, n=4). In conclusion, the incidence of appendiceal neoplasms has increased in recent years, potentially due to increased and earlier detection by newer imaging modalities.

Acute appendicitis, inflammatory appendiceal mass and the risk of a hidden malignant tumor: a systematic review of the literature

Introduction

Acute appendicitis is significantly common. Despite the increased use of computed tomography, the number of perforated cases has been stable in the past three decades. Between 2% and 6% of patients with acute appendicitis present appendiceal mass, often described as inflammatory phlegmon or abscess. Malignant tumors are confirmed by pathological analysis in 0.9–1.4% of all appendectomies performed to treat acute appendicitis. However, recent series demonstrate an elevated incidence of malignancies, ranging from 5.9 to 12%, in patients with inflammatory appendiceal mass.

Methods

The analysis was based on a systematic review of the literature. The articles were searched in PubMed for the period from 1987 to 2016. Articles presenting the incidence of the hidden malignancy among patients with appendiceal inflammatory mass were selected. Variables as age, interval appendectomy rate, the incidence of neoplasm, time to surgery, minimally invasive assessment, histology, right colectomy rate and morbidity were analyzed.

Results

A total of 13.244 patients were described as presenting acute appendicitis. Appendiceal tumor is present in approximately 1% of the appendectomies, while the rate of neoplasm varies from 10 to 29% in patients presenting appendiceal inflammatory mass. Interval appendectomies, despite been the minority of the procedures, disregard the higher morbidity associated with right sided colectomies. The review of literature also describes oncologic, histologic and clinical aspects of patients presenting appendiceal neoplasm, describing the most frequent histologic subtypes of this illness.

Conclusion

Hidden appendiceal neoplasm in acute appendicitis are rare, fortunately. However, its incidence is much higher in patients presenting appendiceal inflammatory mass. Hence, interval appendectomy should be considered in this subgroup of patients.

Appendiceal Abscesses Reduced in Size by Drainage of Pus from the Appendiceal Orifice during Colonoscopy: A Report of Three Cases

Interval appendectomy (IA) for appendiceal abscesses is useful for avoiding extended surgery and preventing postoperative complications. However, IA has problems in that it takes time before an abscess is reduced in size in some cases and in that elective surgery may result in a delay in treatment in patients with a malignant tumor of the appendix. In order to rule out malignancy, we performed colonoscopy on three patients with an appendiceal abscess that did not decrease in size 5 or more days after IA. After malignancy had been ruled out by examination of the area of the appendiceal orifice, the appendiceal orifice was compressed with a colonoscope, and a catheter was inserted through the orifice. Then, drainage of pus was observed from the appendiceal orifice into the cecal lumen. Computed tomography performed 3 days after colonoscopy revealed a marked reduction in abscess size in all patients. No endoscopy-related complication was noted. Colonoscopy in patients with an appendiceal abscess may not only differentiate malignant tumors, but also accelerate reduction in abscess size.

Thigh abscess as an extension of psoas abscess: the first manifestation of perforated appendiceal adenocarcinoma: case report

A 65-year-old woman presented with a painful, swollen, red right thigh and the mild pain in the right abdomen without nausea, vomiting or diarrhoea that lasted for 1 week. Laboratory findings revealed elevated inflammatory markers. Computed tomography of the right thigh, abdomen and pelvis showed an abscess formation in the adductor muscles draining from the abscess that completely occupied the right retroperitoneum up to the diaphragm, dissecting downward through the inguinal canal. Appendix was enlarged with an appendicolith. Emergent exploratory laparotomy revealed a perforated appendix with psoas abscess. Pathohistological diagnosis revealed adenocarcinoma of the appendix. Thigh abscess is an uncommon condition with insidious clinical presentation. Therefore, early recognition and setting of the correct diagnosis enables adequate treatment avoiding additional complications and in some cases potential life-threatening conditions. When upper leg abscess is suspected or proven abdominal examination is mandatory.

Perforation in appendiceal well-differentiated carcinoid and goblet cell tumors: impact on prognosis? A systematic review

BACKGROUND

Carcinoid tumors are the most common malignant lesions arising from Appendix and are mostly found incidentally during surgery for appendicitis. Perforation of Appendix occurs in 10-20% of cases with appendicitis. Currently, no guidelines exist for the treatment of perforated carcinoids of Appendix.

METHODS

A systematic literature search was performed to identify relevant articles on classical carcinoid or goblet cell carcinoid of Appendix in an attempt to evaluate the impact of perforation on management and prognosis. All articles on carcinoids reporting perforation of Appendix were included.

RESULTS

In total, 23 articles on carcinoid of Appendix with an associated perforation were found. Perforation was never investigated or mentioned as a possible negative factor on recurrence or prognosis. Among a total of 103 patients with classical carcinoids and associated perforation, no peritoneal recurrence or death was described, although follow-up data were often unspecified or scarce. Among a total of 18 goblet cell carcinoids with perforation, metastatic spread to the peritoneum was described in one case and two tumor-related deaths occurred among these cases. No specific relation to perforation could be distilled.

CONCLUSIONS

The best available evidence suggests that perforation has no influence on prognosis of classical appendiceal carcinoids. In contrast, peritoneal carcinomatosis is much more common in goblet cell carcinoids but the true impact of perforation remains unclear. Careful follow-up should therefore be considered in these cases.

The accuracy of pre-appendectomy computed tomography with histopathological correlation: a clinical audit, case discussion and evaluation of the literature

The increasing use of computed tomography (CT) in acute appendicitis makes recognising the radiological hallmarks of the condition and its mimics vital. The differential diagnosis includes both appendiceal and nonappendiceal pathologies. The correlation between pre-appendectomy CT and post-appendectomy histopathology was audited retrospectively. Cases of clinico-histopathological discrepancy underwent blind peer-review, and possible improvements were discussed in the context of the medical literature. A grade for discrepancy was given based on the RADPEER scoring system, and interesting or discrepant cases were examined more closely to identify targets for education. Of the 199 procedures, 4 appendectomies were negative (histologically normal), 182 were positive (primary appendicitis) and 13 were incidental (another primary process caused inflammation). The positive predictive value for pre-appendectomy CT was 91.5 %, and the negative appendectomy rate was 2 %. There were many secondary pathologies, including neoplasia, tuberculosis and endometriosis. Although no CT reports missed a diagnosis that should be made “almost all of the time” and in 96 % of cases, the second, blinded radiologist agreed with the initial assessment, in 3 cases, a missed diagnosis altered clinical management; 2 were “understandable” misses but 1 was not. In five cases, a discrepancy was “understandable” but clinically insignificant. Overall, in comparison to the medical literature, the degree of clinico-histopathological correlation was good. Although identifying areas for improvement was challenging, after a pictorial review of four cases and a discussion of the medical literature, we present our audit results and some valuable learning points for use in the CT assessment of suspected acute appendicitis.

Incidentally Discovered Adenocarcinoma in situ of the Appendix in a Young Woman

Primary appendiceal adenocarcinoma is an infrequent disease. This report presents a rare case of incidentally discovered carcinoma in situ of the appendix. A 35-year-old parturient female simultaneously underwent appendectomy and oophorectomy due to an ovarian abscess that adhered to the appendix during cesarean section. Although her excised appendix showed no apparent tumorous lesion, histopathological examination revealed carcinoma in situ in the excised appendix. She underwent additional right hemicolectomy a few days later due to the possibility of a positive surgical margin. Histopathological examination detected no malignant cells in the resected specimen. She was discharged without any complications and has since remained healthy. Appendiceal adenocarcinoma is generally considered to be difficult to diagnose during the early stage because it seldom shows any specific findings. This results in a poor prognosis. Histopathological examination is not always conducted for appendices resected during other surgery. However, the current study suggests that a careful routine histopathological examination of excised appendix, as well as careful preoperative examination and detailed intraperitoneal inspection during surgery, is indeed important to detect occult appendiceal tumors.

Periappendiceal abscess mimicking appendiceal cancer

Appendiceal cancer was strongly suspected in this case because of its unique colonoscopic, radiologic, and intraoperative presentation. Hence, laparoscopic enbloc right hemicolectomy and peritonectomy were performed. The diagnosis of periappendiceal abscess was confirmed later after the operation. Appendiceal disease is hard to differentiate because of the wide spectrum of differential diagnosis. So, when there is a strong suspicion of appendiceal cancer, laparoscopic right colectomy, which is minimally invasive and potentially curative can be the treatment of choice.