Demographic trends in the incidence of malignant appendiceal tumours in England between 1995 and 2016: Population-based analysis

Predicting Survival in Mucinous Adenocarcinoma of the Appendix: Demographics, Disease Presentation, and Treatment Methodology

BACKGROUND

Mucinous adenocarcinoma of the appendix (MACA) follows a complex disease course with variable survival. Large-scale predictive modeling may determine subtle yet important prognostic factors otherwise unseen in smaller cohort analyses.

METHODS

Patients with MACA were identified from the Surveillance, Epidemiology, and End Results (SEER) Research Plus database (2005-2019). Primary, secondary, and tertiary outcomes were disease-specific survival (DSS), overall survival (OS), and average annual percent change (AAPC) in incidence.

RESULTS

Among 4,258 included patients, MACA was most frequently diagnosed at 50 to 69 years (52.0%), with female preponderance (55.9%). MACA incidence AAPC was 3.8 (95% confidence interval [CI] 1.9-5.9). For patients with exclusive, first-diagnosis MACA included in survival analysis (3,222 patients), median DSS and OS were 118 and 88 months, respectively. In DSS-based multivariable analysis, worse prognosis was associated with non-Hispanic Black background (HR 1.36, 95% CI 1.02-1.82; p = 0.036), high grade (grade 3 HR 3.10, 95% CI 2.44-3.92; p < 0.001), lymphatic spread (HR 2.73, 95% CI 2.26-3.30; p < 0.001), and distant metastasis (HR 5.84, 95% CI 3.86-8.83; p < 0.001). In subcohort analysis of patients with rationale for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC, 2,387 patients), CRS-HIPEC was associated with survival benefit compared with surgery alone but only for moderate-grade tumors (median DSS/OS 138/138 vs. 116/87 months; p < 0.001).

CONCLUSIONS

Mucinous adenocarcinoma of the appendix incidence is increasing in the United States. Survival rates are affected by both demographics and classical risk factors, and CRS-HIPEC-associated survival benefit predominantly occurs in moderate-grade tumors. Further exploration of biologic and clinicopathologic features may enhance risk stratification for this disease.

Timely Review and Communication of Histopathology Reports Following Appendicectomy: Insights from a Two-Cycle Clinical Audit

INTRODUCTION

Appendicectomy is the most frequent emergency general surgical procedure. Prior research highlights the importance of histopathology analysis after appendicectomy which is the practice in many countries including the United Kingdom (UK), aiming to prevent any oversight of vital findings and the avoidance of potential delays in patient care. Our primary objective was to audit the extent to which surgeons adhere to the NHS England patient safety guidelines from 2016 when it comes to timely reviewing and effectively communicating histopathology results to patients and/or their general practitioners following appendicectomy procedures. Our secondary objective was to amend practice, if deemed necessary, following the implementation of agreed-upon protocols, with the expected improvements being observable in the second cycle of the audit.

METHODS

In our two-cycle audit, we performed a retrospective analysis using online patient records from a single centre in the UK. The initial cycle involved cases of emergency appendectomies carried out consecutively for suspected appendicitis from April 2018 to June 2019. Following the clinical governance meeting and the implementation of recommendations, the second audit cycle covered cases between September 2020 and October 2020.

RESULTS

In the first cycle, among 418 laparoscopic appendectomies, 207 (49.52%) and 47 reports (11.24%) were reviewed within a 15-day and a 16-30-day window, respectively, following the online availability of histopathology results. Notably, 116 reports (27.75%) remained unreviewed by surgeons, and only 67 (16.02%) of these reports documented communication with patients and/or their general practitioners. In the second cycle, involving 49 patients, 38 reports (77.55%) were reviewed within the first 15 days, and 10 reports (20.4%) were reviewed between 16-30 days. Among these, 16 reports (32.65%) documented communication with patients and/or their general practitioners.

CONCLUSIONS

Our adherence to the aforementioned guidance was poor prior to this audit. This two-cycle audit highlighted the need for improvement in the timely review and communication of histopathology reports following appendectomy at our centre. The second cycle showed promising progress, suggesting that changes implemented between the cycles had a positive impact. Nevertheless, continuous efforts may be required to enhance and sustain adherence to these vital patient safety guidelines.

Case report: A rare case of coexistence of low-grade appendiceal mucinous neoplasia and goblet cell adenocarcinoma in the appendix

Background

Primary appendiceal tumors are rare. Low-grade appendiceal mucinous neoplasia (LAMN) and goblet cell adenocarcinoma (GCA) account for 20% and 14% of primary appendiceal tumors, respectively. The coexistence of LAMN and GCA is an extremely rare event. This report presents a case of an elderly male patient with an appendiceal tumor composed of LAMN and GCA in the same appendix.

Case presentation

A 72-year-old male patient was admitted to our institution presenting with a history of abdominal pain localized to the right lower quadrant for two months. Abdominal computed tomography (CT) showed a large dilated thickened cystic mass in the appendix, along with a small duodenal diverticulum. Laboratory tests indicated elevated levels of serum carcinoembryonic antigen (CEA) and cancer antigen 199 (CA19-9) markers. The patient underwent a laparoscopic right hemicolectomy and exploration of the duodenal diverticulum, and there was no finding of perforation of the duodenal diverticulum. Focal positivity for chromogranin A (CgA) and synaptophysin (Syn) was observed in the tumor cells of GCA. The final pathological diagnosis revealed the coexistence of LAMN staged pT4a and grade 1 GCA staged pT3 in the appendix. Unfortunately, the patient died due to severe septic shock and circulatory failure secondary to a perforated duodenal diverticulum.

Conclusions

The coexistence of LAMN and GCA are extremely rare in the appendix and may result from the proliferation of two independent cellular lines. The coexistence of distinct neoplasms poses diagnostic and management challenges. Multidisciplinary team discussion may be essential in the effective management of these patients.

Appendiceal adenocarcinoma, diagnosed after acute perforated appendicitis: Potential contribution of HIPEC

INTRODUCTION

Treatment of peritoneal metastasis from appendicular adenocarcinoma consists of cyto-reductive surgery (CRS) and Hyperthermic IntraPEritoneal Chemotherapy (HIPEC). In case of acute appendicular syndrome (AAS) the tumor is likely to be perforated. In that case, there is no treatment recommendation. We propose CRS and HIPEC.

MATERIALS AND METHOD

We listed 21 consecutive patients who were addressed for discovery of appendiceal adenocarcinoma. The emergency surgery was performed in a primary-care hospital. We evaluated the therapeutic algorithms, per operative decision, survival and recurrent rate.

RESULTS

Among the 21 patients, 4 patients were diagnosed as synchronous appendicular peritoneal metastasis, and underwent CRS and HIPEC. The other 17 patients with diagnosis of adenocarcinoma on anatomopathological samples, without peritoneal metastasis during appendectomy, were addressed. Between them 2 patients were denied CRS. Among the 15 operated patients, 8 patients had no peritoneal metastasis discovery during surgery, and therefore underwent prophylactic CRS and HIPEC. Peritoneal metastasis were discovered for the other 7 patients, who also underwent CRS and HIPEC. For the prophylactic group, the recurrence rate is 12,5 %, overall survival (OS) is 100 %. The rate of grade III-IV surgical complications after CRS and HIPEC was 36 % among the 19 patients who underwent surgery.

CONCLUSION

In case of appendectomy in emergency situations for perforated adenocarcinoma, half of the patients may have peritoneal metastasis. In case of non-identified peritoneal metastasis during CRS, performing a prophylactic HIPEC seems to be associated with an encouraging rate of peritoneal disease free situation at 5 years.

Sufficient Regional Lymph Node Examination for Staging Adenocarcinoma of the Appendix

BACKGROUND

The presence of lymph node (LN) metastasis is a known negative prognostic factor in appendix cancer (AC) patients. However, currently the minimum number of LNs required to adequately determine LN negativity is extrapolated from colorectal studies and data specific to AC is lacking. We aimed to define the lowest number of LNs required to adequately stage AC and assess its impact on oncologic outcomes.

METHODS

Patients with stage II-III AC from the National Cancer Database (NCDB 2004-2019) undergoing surgical resection with complete information about LN examination were included. Multivariable logistic regression assessed the odds of LN positive (LNP) disease for different numbers of LNs examined. Multivariable Cox regressions were performed by LN status subgroups, adjusted by prognostic factors, including grade, histologic subtype, surgical approach, and documented adjuvant systemic chemotherapy.

RESULTS

Overall, 3,602 patients were included, from which 1,026 (28.5%) were LNP. Harvesting ten LNs was the minimum number required without decreased odds of LNP compared with the reference category (≥ 20 LNs). Total LNs examined were < 10 in 466 (12.9%) patients. Median follow-up from diagnosis was 75.4 months. Failing to evaluate at least ten LNs was an independent negative prognostic factor for overall survival (adjusted hazard ratio 1.39, p < 0.01).

CONCLUSIONS

In appendix adenocarcinoma, examining a minimum of ten LNs was necessary to minimize the risk of missing LNP disease and was associated with improved overall survival rates. To mitigate the risk of misclassification, an adequate number of regional LNs must be assessed to determine LN status.

Current Status of Treatment among Patients with Appendiceal Tumors-Old Challenges and New Solutions?

The 5th edition of the World Health Organization (WHO) classification of tumors of the digestive system distinguishes four categories of appendiceal tumors (ATs): serrated lesions and polyps, mucinous neoplasms, adenocarcinomas, and neuroendocrine neoplasms (NENs). The differential diagnosis of ATs can be challenging in medical practice, due to their rarity and lack of data from randomized controlled trials on a large, diverse group of patients. ATs are usually noted in specimens obtained during appendectomies due to clinical acute appendicitis. In the European population, most ATs (65%) occur over the age of 50 and among women (56.8%). According to histological type, 54.6% are neuroendocrine tumors (NETs); 26.8% cystic, mucinous, and serous neoplasms; and 18.6% adenocarcinoma not otherwise specified (NOS). On pathologic analysis, most AT findings are benign lesions or small NENs that do not require further therapeutic measures. The presence of appendiceal mucinous neoplasm (AMN) can lead to pseudomyxoma peritonei (PMP). While the multimodal treatment for abdominal malignancies has evolved over the past several decades, the clinical workup and treatment of ATs remain a challenge. Therefore, this review aims to describe the diagnostic possibilities, molecular-based diagnosis, staging, differences in the treatment process, and prognostic factors associated with ATs.

Incidence rate and histology of appendiceal neoplasms in complicated versus uncomplicated appendicitis: A meta-analysis and systematic review

INTRODUCTION

Studies evaluating the rate and histology of appendiceal neoplasms between complicated and uncomplicated appendicitis include a small number of patients. Therefore, we sought a meta-analysis and systematic review comparing the rates and types of appendiceal neoplasm between complicated and uncomplicated appendicitis.

METHODS

We included articles published from the time of inception of the datasets to September 30, 2022. The electronic databases included English publications in Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, and Scopus.

RESULTS

A total of 4962 patients with appendicitis enrolled in 4 comparative studies were included. The mean age was 43.55 years (16- 94), and half were male (51%). Based on intra-operative findings, 1394 (38%) had complicated appendicitis, and 3558 (62%) had uncomplicated appendicitis. The overall incidence rate of neoplasm was 1.98%. No significant difference was found in the incidence rate of appendiceal neoplasm between complicated (3.29%) and uncomplicated (1.49%) appendicitis (OR 0.44, 95% CI 0.16- 1.23; p < 0.087; I2 = 54.9%). The most common appendiceal neoplasms were Neuroendocrine Tumors (NET) (49.21%), Nonmucinous Adenocarcinoma (24.24%), Mixed Adeno-Neuroendocrine Tumor (MANEC) (11.40%), Mucinous Adenocarcinoma (4.44%). There was a significant difference between complicated and uncomplicated appendicitis in rates of adenocarcinoma (50% vs. 13%), NET (31% vs. 74%), MANEC (19% vs. 13%) (P < 0.001).

CONCLUSION

While there was no significant difference in the overall neoplasm rate between complicated and uncomplicated appendicitis, the NET rate was significantly higher in uncomplicated appendicitis. In comparison, the Adenocarcinoma rate was considerably higher in Complicated appendicitis. These findings emphasize the importance of evaluating risk factors for neoplasm when considering appendectomy in patients with appendicitis.

Survival outcomes used to validate version 9 of the American Joint Committee on Cancer staging system for appendiceal cancer

The standard for cancer staging in the United States for all cancer sites, including primary carcinomas of the appendix, is the American Joint Committee on Cancer (AJCC) staging system. AJCC staging criteria undergo periodic revisions, led by a panel of site-specific experts, to maintain contemporary staging definitions through the evaluation of new evidence. Since its last revision, the AJCC has restructured its processes to include prospectively collected data because large data sets have become increasingly robust and available over time. Thus survival analyses using AJCC eighth edition staging criteria were used to inform stage group revisions in the version 9 AJCC staging system, including appendiceal cancer. Although the current AJCC staging definitions were maintained for appendiceal cancer, incorporating survival analysis into the version 9 staging system provided unique insight into the clinical challenges in staging rare malignancies. This article highlights the critical clinical components of the now published version 9 AJCC staging system for appendix cancer, which (1) justified the separation of three different histologies (non-mucinous, mucinous, signet-ring cell) in terms of prognostic variance, (2) demonstrated the clinical implications and challenges in staging heterogeneous and rare tumors, and (3) emphasized the influence of data limitations on survival analysis for low-grade appendiceal mucinous neoplasms.

High Incidence of Appendiceal Neoplasms in the Elderly: A Critical Concern for Non-Surgical Treatment

OBJECTIVE

Appendiceal neoplasms (ANs) are rare tumors that are often discovered incidentally during histopathological examinations. The increasing incidence of ANs is a critical issue in the non-operative management of acute appendicitis. This study aimed to document the temporal trends over a 12-year period by analyzing the clinical presentation, imaging findings, and histopathological features of ANs.

SUBJECTS AND METHODS

Health records of patients who underwent appendectomy from 2011 to 2022 were examined. Demographic and clinical data, laboratory results, imaging findings, and histopathological features were documented. The characteristics of both ANs and non-neoplastic cases were evaluated.

RESULTS

A total of 22,304 cases were identified, of which 330 (1.5%) were diagnosed with ANs. The odds ratio for ANs increased with age, with the highest odds ratio observed in patients aged 70 or older. Receiver Operating Characteristic analysis showed that age and appendiceal diameter were significant predictors of ANs. An optimal age cut-off point of 28.5 years was determined, yielding a sensitivity of 72% and a specificity of 64%. For appendiceal diameter, the optimal cut-off was found to be 9.5 mm, exhibiting a sensitivity of 77% and a specificity of 56%.

CONCLUSION

Although the incidence of ANs remains relatively low, a steady increase has been observed over the past decade. The increasing rate of ANs raises concerns regarding non-surgical management options. The results of this study highlight the importance of considering ANs as a potential diagnosis in older patients and in patients with an appendix diameter greater than 9.5 mm. These findings may have implications for treatment and management.

The other colon cancer: a population-based cohort study of appendix tumour trends and prognosis

AIM

Appendiceal neoplasms are rare subtypes of colorectal tumours that mainly affect younger patients some 20 years earlier than other colon tumours. The aim of this study was to gain more insight into the histological subtypes of this rare disease and include cases previously excluded, such as mucinous neoplasia.

METHOD

The cohort study included 1097 patients from the Munich Cancer Registry (MCR) diagnosed between 1998 and 2020. Joinpoint analysis was used to determine trend in incidence. Baseline demographic comparisons and survival analyses using competing risk and univariate/multivariate methods were conducted according to tumour histology: adenocarcinoma (ADENO), neuroendocrine neoplasia (NEN), mixed adeno-neuroendocrine carcinoma (MANEC), and low- (LAMN) and high-grade mucinous neoplasia (HAMN).

RESULTS

Up to 2016 the number of cases increased significantly [annual per cent change (APC) = 6.86, p < 0.001] followed by a decline in the following years (APC = -14.82, p = 0.014; average APC = 2.5, p = 0.046). Comparison of all patients showed that NEN (48.4%) and mucinous neoplasms (11.6%) had a considerably better prognosis than ADENO (36.0%) and MANEC (3.0%, p < 0.0001). A multivariate analysis within the NEN and ADENO subgroups revealed that further histological classification was not prognostically relevant, while older age and regional tumour spread at diagnosis were associated with a poor prognosis. ADENO histology with high tumour grade and appendectomy only was also associated with poorer survival.

CONCLUSION

Appendiceal neoplasms are histologically heterogeneous; however, this diversity becomes less relevant compared with the marked difference from cancers of the remaining colon. The previously observed increase in cases appears to be abating; fewer cases of appendicitis and/or appendectomies or changes in histopathological assessment may be behind this trend.