Laparoscopic accuracy in prediction of appendiceal pathology: oncologic and inflammatory aspects

Analysis of appendiceal neoplasms in 1,423 appendectomy specimens: a 10-year retrospective cohort study from a single institution

OBJECTIVE

This study aimed to reveal the incidence, clinicopathological, and oncological outcomes of appendiceal neoplasms.

METHODS

This is a retrospective cohort study from a single institution. Patients with a pathological diagnosis of malignancy who underwent appendectomy between January 2011 and 2021 were included in the study, and groups were formed according to pathological type. Clinical, pathological, and oncological results were compared in these groups.

RESULTS

The incidence of neoplasia was 2.38% (n=34) in a cohort of 1,423 appendectomy cases. Of the cases, 56% (n=19) were female. The median age in the entire cohort was 55.5 (range: 13-106) years. In the cohort, the rate of neuroendocrine tumor mucinous cystadenoma adenocarcinoma, and low-grade appendiceal mucinous neoplasm, according to the American Joint Committee on Cancer classification of appendiceal neoplasms, was 32.3% (n=11), 26.4% (n=9), 26.4% (n=9), and 14.7% (n=5), respectively. Neuroendocrine tumor patients (median age: 35 years) were younger than the other groups (p=0.021). Secondary complementary surgery was performed in 66.7% (n=6) of adenocarcinoma patients and 27.3% (n=3) of neuroendocrine tumor patients. Right hemicolectomy was performed in all neuroendocrine tumor patients requiring secondary surgery, while right hemicolectomy was performed in three adenocarcinoma patients and cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in three adenocarcinoma patients. After a median follow-up of 44.4 months (95% confidence interval: 18.6-70.1), the mean survival rate was 55% in appendiceal adenocarcinoma patients compared to 100% in neuroendocrine tumor patients.

CONCLUSION

Appendiceal neoplasms are rare but remain an important cause of mortality. Appendiceal adenocarcinomas are associated with poorer oncological outcomes compared to other neoplasms.

Management of Appendix Neuroendocrine Neoplasms: Insights on the Current Guidelines

Appendiceal neuroendocrine neoplasms (ANENs) usually present as incidental findings at the time of appendectomy for acute appendicitis. They are rare, accounting for only 0.5-1% of intestinal neoplasms; they are found in 0.3-0.9% of all appendectomy specimens. They are usually sporadic tumors. There are several histological types including well-differentiated neuroendocrine tumors (NETs), poorly differentiated neuroendocrine carcinomas (NECs), and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs). Histologic differentiation and the grade of well-differentiated NETs correlate with clinical behavior and prognosis. Management varies based on differentiation, aggressiveness, and metastatic potential. There is debate about the optimal surgical management for localized appendiceal NETs that are impacted by many factors including the tumor size, the extent of mesoappendiceal spread, lymphovascular invasion and perineural involvement. In addition, the data to guide therapy in metastatic disease are limited due to the paucity of these tumors. Here, we review the current advances in the management of ANENs within the context of a multidisciplinary approach to these tumors.

Diagnosing granulomatous disease during appendectomy

Difficulties during surgery are uncommon situations in appendectomy. For granulomatous appendicitis, literature is insufficient about surgical findings. The procedure of a 17-year-old male patient was a struggle due to adhesions. I thought a surgeon could expect granulomatous diseases by evaluating the macroscopic appearance of the appendix during surgical procedure.

Incidental appendiceal mass as the only manifestation of endometriosis

Appendiceal endometriosis is a rare condition that remains difficult to diagnose preoperatively. Herein, we present a case of appendiceal endometriosis presenting as a neuroendocrine tumor. A 34-year-old Caucasian woman was found to have an appendiceal mass with a small fluid collection on routine transvaginal ultrasound. The patient denied any symptoms. Features were consistent with those of a neuroendocrine tumour of the appendix. Laparoscopic appendectomy followed by histopathology revealed endometriosis with negative cytology for malignant cells. Preoperative characteristics of appendiceal tumours in women of childbearing age should be further investigated. Establishing clinical and surgical guidelines is the key to avoid invasive procedures and related adverse outcomes.

Evaluation of concordance among surgeons and pathologists regarding the diagnosis and classification of acute appendicitis in children

Acute appendicitis is the most frequent urgent abdominal surgical pathology in children. Therapeutic decisions in patients who have undergone an appendectomy are made based on the macroscopic findings at the moment of surgery. There is high variability between surgical and histopathological findings.

METHOD

Concordance among surgeons and pathologists regarding the diagnosis and classification of acute appendicitis was assessed in children who have undergone an appendectomy. Surgical site infection (SSI) incidence was measured for both the surgical and pathological classification.

RESULTS

The statistical analysis included 1092 children. The pathologists confirmed the presence of appendicitis in 90.4% of the patients. Concordance in the diagnosis of appendicitis among surgeons and pathologists was weak (kappa 0.57), while concordance in the classification of perforated or non-perforated appendicitis was moderate (kappa 0.7). There were no significant differences in these findings determined by the surgeons' experience or the open or laparoscopic approach. In the discordant group of 70 patients in which the surgeon classified the appendicitis as non-perforated but the pathologist classified as perforated, just one patient developed an intra-abdominal abscess.

CONCLUSIONS

The classification of appendicitis as perforated or non-perforated shows moderate concordance between the surgical and histopathological diagnosis. This concordance is not determined by the surgeons' experience or the surgical approach.

TYPE OF STUDY

Diagnostic Test LEVEL OF EVIDENCE: Level II.

Increased risk of malignancy for patients older than 40 years with appendicitis and an appendix wider than 10 mm on computed tomography scan: A post hoc analysis of an EAST multicenter study

BACKGROUND

The incidence of underlying malignancy in appendicitis ranges between 0.5% and 1.7%. We sought to identify the subset of patients with appendicitis who are at increased risk of appendiceal malignancy.

METHODS

Using the Eastern Association for the Surgery of Trauma Multicenter Study of the Treatment of Appendicitis in America: Acute, Perforated, and Gangrenous database, we included all patients from 28 centers undergoing immediate, delayed, or interval appendectomy between 2017 and 2018. Univariate then multivariable analyses were performed to compare patients with and without malignancy and to identify independent demographic, clinical, laboratory, and/or radiological predictors of malignancy. Akaike information criteria for regression models were used to evaluate goodness of fit.

RESULTS

A total of 3,293 patients were included. The median age was 38 (27-53) years, and 46.5% were female patients. On pathology, 48 (1.5%) had an underlying malignancy (adenocarcinoma [60.4%], neuroendocrine [37.5%], and lymphoma [2.1%]). Patients with malignancy were older (56 [34.5-67] vs 37 [27-52] years, P < .001), had longer duration of symptoms before presentation (36-41 vs 18-23 hours, P = .03), and were more likely to have a phlegmon on imaging (6.3% vs 1.3%, P = .03). Multivariable analyses showed that an enlarged appendiceal diameter was independently associated with malignancy (odds ratio = 1.06, 95% confidence interval = 1.01-1.12; P = .01). The incidence of malignancy in patients >40 years with an appendiceal diameter >10 mm on computed tomography was 2.95% compared with 0.97% in patients ≤40 years old with appendiceal diameter ≤10 mm. The corresponding risk ratio for that population was 3.03 (95% confidence interval: 1.24-7.42; P = .02).

CONCLUSION

The combination of age >40 and an appendiceal diameter >10 mm is associated with a greater than 3-fold increased risk of malignancy in patients presenting with appendicitis.

Management of the normal-appearing appendix during laparoscopy for clinically suspected acute appendicitis in the pediatric population

PURPOSE

The widespread use of laparoscopy has brought forth the question of how to manage a macroscopically normal-appearing appendix in cases of clinically suspected appendicitis. This study aimed to determine the current practices of pediatric general surgeons in Canada regarding this matter.

METHODS

An online survey was created following the American Pediatric Surgical Association (APSA) guidelines and distributed via email to the Canadian Association of Pediatric Surgeons (CAPS) staff surgeons. The questions assessed clinician characteristics, standard practice, and rationale. Results were analyzed using descriptive statistics.

RESULTS

A total of 54/72 (75%) CAPS members practicing in Canada completed the survey. All (100%) agreed they would remove a normal-appearing appendix during laparoscopy for suspected acute appendicitis. The most common reasons were: possibility of microscopic appendicitis (39/54, 72.2%), avoiding future diagnostic confusion (28/54, 51.9%), and patient preference/consent discussion (21/54, 38.9%). Most (53/54, 98.1%) had performed a negative appendectomy and 49/54 (90.7%) agreed there were no sufficient guidelines.

CONCLUSIONS

The majority of pediatric surgeons agree sufficient guidelines do not exist to support decision making when a normal-appearing appendix is found during laparoscopy for suspected acute appendicitis. This survey shows that removal of the appendix in this case would be supported by the majority of Canadian pediatric surgeons.

TYPE OF STUDY

Survey LEVEL OF EVIDENCE: VII (Expert Opinion).

Risk factors for appendiceal neoplasm and malignancy among patients with acute appendicitis

PURPOSE

Non-operative management of acute uncomplicated appendicitis has shown promising results but might carry the risk of delayed diagnosis of premalignant or malignant appendiceal tumors found by chance in 0.7-2.5% of appendiceal specimen after appendectomy. Purpose of this study was to analyze whether appendiceal tumors are associated with a complicated appendicitis and to determine risk factors for appendiceal neoplasm and malignancy in patients with acute appendicitis.

METHODS

We performed a retrospective analysis of 1033 adult patients, who underwent appendectomy for acute appendicitis from 2010 to 2016 at the University hospital Erlangen. Data included patients' demographics; comorbidities; pre-, intra- and postoperative findings; and histopathological results. Complicated appendicitis was defined in the presence of perforation or abscess.

RESULTS

Appendiceal neoplasm respectively malignancy rate was 2.8% respectively 1.5%. Using univariate analysis, we identified seven risk factors at least for appendiceal neoplasm or malignancy: age, ASA, C-reactive protein, appendiceal diameter, perforation, intraoperative perithyphilitic abscess, and complicated appendicitis. Risk for appendiceal neoplasm or malignancy was 4.4% respectively 2.7% in complicated acute appendicitis compared to 2.0% respectively 1.0% in uncomplicated appendicitis (p = 0.043 respectively p = 0.060). In multivariate analysis, age ≥ 50 years and a diameter of the appendix in the sonography ≥ 13 mm were independent risk factors predicting the presence of appendiceal neoplasm and malignancy.

CONCLUSION

Among patients with appendicitis, there are relevant risk factors predicting appendiceal tumors, especially age and appendiceal diameter in sonography. But the identified risk factors have a low sensitivity and specificity, so obtaining a confident preoperative diagnosis is challenging.

Predicting appendiceal tumors among patients with appendicitis

BACKGROUND

As nonoperative management of appendicitis gains popularity, vigilance for appendiceal tumors becomes increasingly important. We hypothesized that, among patients presenting with acute appendicitis, those with advanced age, multiple comorbidities, atypical presentation, and complicated appendicitis would be more likely to have underlying appendiceal tumors.

METHODS

We performed a 4-year retrospective cohort analysis of 677 consecutive adult patients who underwent appendectomy for appendicitis at our tertiary care center. Patients with an appendiceal tumor on their final pathology report were compared to patients with no tumor. Conditions present on admission were used to create a multivariate logistic regression model to predict appendiceal tumor. Risk factors were reported as odds ratio (OR) [95% CI]. Model strength was assessed by area under the receiver operating characteristic curve.

RESULTS

Seventeen patients (2.5%) had an appendiceal tumor. Within this group. 14 underwent immediate appendectomy, two initially had nonoperative management but failed to improve on antibiotics and underwent appendectomy during the initial admission, and one had successful nonoperative management and elective appendectomy 19 days after discharge. Four variables contributed to the multivariate model to predict the presence appendiceal tumor: age ≥ 50 (OR 3.6 [1.1-11.4]), outpatient steroid/immunosuppressant use (OR 12.1 [2.0-72.5]), the absence of migratory right lower quadrant pain (OR 4.7 [1.2-18.1]), and the appearance of a phlegmon on CT scan (OR 7.0 [1.6-30.2]); model area under the receiver operating characteristic curve: 0.860 [0.705-0.969].

CONCLUSION

For patients presenting with acute appendicitis, conditions present on admission may predict underlying appendiceal tumor. Patients with advanced age, multiple comorbidities, atypical presentation, and complicated appendicitis should be considered for appendectomy during the index admission or at earliest convenience if nonoperative management is necessary.

LEVEL OF EVIDENCE

Prognostic study, level III.

Incidence of Appendicitis over Time: A Comparative Analysis of an Administrative Healthcare Database and a Pathology-Proven Appendicitis Registry

Importance

At the turn of the 21^st century, studies evaluating the change in incidence of appendicitis over time have reported inconsistent findings.

Objectives

We compared the differences in the incidence of appendicitis derived from a pathology registry versus an administrative database in order to validate coding in administrative databases and establish temporal trends in the incidence of appendicitis.

Design

We conducted a population-based comparative cohort study to identify all individuals with appendicitis from 2000 to2008.

Setting & Participants

Two population-based data sources were used to identify cases of appendicitis: 1) a pathology registry (n = 8,822); and 2) a hospital discharge abstract database (n = 10,453).

Intervention & Main Outcome

The administrative database was compared to the pathology registry for the following a priori analyses: 1) to calculate the positive predictive value (PPV) of administrative codes; 2) to compare the annual incidence of appendicitis; and 3) to assess differences in temporal trends. Temporal trends were assessed using a generalized linear model that assumed a Poisson distribution and reported as an annual percent change (APC) with 95% confidence intervals (CI). Analyses were stratified by perforated and non-perforated appendicitis.

Results

The administrative database (PPV = 83.0%) overestimated the incidence of appendicitis (100.3 per 100,000) when compared to the pathology registry (84.2 per 100,000). Codes for perforated appendicitis were not reliable (PPV = 52.4%) leading to overestimation in the incidence of perforated appendicitis in the administrative database (34.8 per 100,000) as compared to the pathology registry (19.4 per 100,000). The incidence of appendicitis significantly increased over time in both the administrative database (APC = 2.1%; 95% CI: 1.3, 2.8) and pathology registry (APC = 4.1; 95% CI: 3.1, 5.0).

Conclusion & Relevance

The administrative database overestimated the incidence of appendicitis, particularly among perforated appendicitis. Therefore, studies utilizing administrative data to analyze perforated appendicitis should be interpreted cautiously.

Incidental appendectomy? Microscopy tells another story: A retrospective cohort study in patients presenting acute right lower quadrant abdominal pain

BACKGROUND

Optimal management of macroscopically normal appendix encountered during laparoscopy for acute abdominal pain is still unclear.

METHODS

164 acute abdominal pain cases in which laparoscopy showed a normal appendix were reviewed. No other intra-peritoneal acute disease was present in 50 patients (Group 1) whereas a miscellanea of intra-peritoneal conditions was identified in the other 114 (Group 2). All the patients underwent appendectomy with specimen examination.

RESULTS

Following incidental appendectomy significant microscopical changes were seen in 125 specimens (76%). Among these, inflammation was found in 122 and neuroendocrine tumors in 3. Appendices harbored pathological changes in n = 45 patients (90%) of Group 1 and in n = 34 patients (70%) of Group 2 patients (p < 0.05). Morbidity for incidental appendectomy was 2%.

CONCLUSION

This study supports an appendectomy in patients who are undergoing laparoscopy for acute right lower quadrant abdominal pain even when the appendix appears normal on visual inspection.

Intraoperative motive for performing a laparoscopic appendectomy on a postoperative histological proven normal appendix

Background:

Diagnostic laparoscopy is the ultimate tool to evaluate the appendix. However, the intraoperative evaluation of the appendix is difficult, as the negative appendectomy rate remains 12%–18%. The aim of this study is to analyze the intraoperative motive for performing a laparoscopic appendectomy of an appendix that was proven to be noninflamed after histological examination.

Methods:

In 2008 and 2009, in five hospitals, operation reports of all negative laparoscopic appendectomies were retrospectively analyzed in order to assess the intraoperative motive for removing the appendix.

Results:

A total of 1,465 appendectomies were analyzed with an overall negative appendectomy rate of 9% (132/1,465). In 57% (841/1,465), a laparoscopic appendectomy was performed, with 9% ( n = 75) negative appendectomies. In 51% of the negative appendectomies, the visual assessment of the appendix was decisive in performing the appendectomy. In 33%, the surgeon was in doubt whether the appendix was inflamed or normal. In 4%, the surgeon was aware he removed a healthy appendix, and in 9%, an appendectomy was performed for different reasons.

Conclusion:

In more than half of the microscopic healthy appendices, the surgeon was convinced of the diagnosis appendicitis during surgery. Intraoperative laparoscopic assessment of the appendix can be difficult.