Incidental Findings in Routine Histopathological Examination of Appendectomy Specimens; Retrospective Analysis of 1970 Patients

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.

Disseminated appendicular lymphoma presenting as acute appendicitis: a case report

Introduction and importance

Acute appendicitis is a common surgical emergency marked by appendix inflammation, presenting as acute abdominal pain and typically treated with appendectomy. The authors report a rare case of disseminated appendicular lymphoma presenting as acute appendicitis. Acute appendicitis is a common surgical emergency.

Case presentation

This case involved a 75-year-old male patient who underwent appendectomy, revealing an enlarged appendix with lymphomatous nodules.

Clinical discussion

Lymphoma involvement in the appendix is extremely rare, and lymphomas presenting as acute appendicitis are even more exceptional. Imaging investigations, including ultrasound and CECT scan of the abdomen, are recommended to aid in diagnosis. On computed tomography, appendiceal lymphoma is characterized by markedly diffuse mural soft-tissue thickening with preserved vermiform morphology and occasional aneurysmal dilatation of the lumen.

Conclusion

This case underscores the importance of considering unusual etiologies in atypical appendicitis presentations.

Laparoscopic resection for appendiceal mucocele secondary to endometriosis: A case report

INTRODUCTION

This case report describes a patient who underwent laparoscopic resection of the mucocele of the appendix secondary to endometriosis, a rarity in clinical practice.

PATIENT CONCERNS

The patient was a 38-year-old woman with a history of endometriosis and an ovarian cyst who sought medical advice with a chief complaint of mild right lower abdominal pain.

DIAGNOSES

Computed tomography and ultrasonography of the abdomen revealed a cystic lesion at the distal end of the appendix without definitive findings of malignancy. Colonoscopy revealed a submucosal tumor-like elevation at the appendiceal orifice. Appendiceal mucocele was suspected preoperatively.

INTERVENTIONS

The lesion was resected laparoscopically. Secondary ileocecal resection with lymphadenectomy was possible if the resected specimen was pathologically diagnosed as a malignant tumor with the risk of lymph node metastasis.

OUTCOMES

The resected specimen was pathologically diagnosed as an appendiceal mucocele secondary to endometriosis; therefore, additional surgery was avoided.

CONCLUSION

Although appendiceal mucoceles secondary to endometriosis are rare, laparoscopic surgery in which only the lesion was resected is a useful strategy for the treatment and pathological diagnosis of appendiceal mucoceles without findings of malignancy.

Neoplasms of the Appendix

BACKGROUND

Neoplasms of the vermiform appendix are rare. They comprise a heterogeneous group of entities requiring differentkinds of treatment.

METHODS

This review is based on publications retrieved by a selective literature search in the PubMed, Embase, and Cochranedatabases.

RESULTS

0.5% of all tumors of the gastrointestinal tract arise in the appendix. Their treatment depends on their histopathologicalclassification and tumor stage. The mucosal epithelium gives rise to adenomas, sessile serrated lesions, adenocarcinomas,goblet-cell adenocarcinomas, and mucinous neoplasms. Neuroendocrine neoplasms originate in neuroectodermal tissue. Adenomasof the appendix can usually be definitively treated by appendectomy. Mucinous neoplasms, depending on their tumorstage, may require additional cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemoperfusion (HIPEC). Adeno -carcinomas and goblet-cell adenocarcinomas can metastasize via the lymphatic vessels and the bloodstream and should thereforebe treated by oncological right hemicolectomy. Approximately 80% of neuroendocrine tumors are less than 1 cm in diameterwhen diagnosed and can therefore be adequately treated by appendectomy; right hemicolectomy is recommended if the patienthas risk factors for metastasis via the lymphatic vessels. Systemic chemotherapy has not been shown to be beneficial forappendiceal neoplasms in prospective, randomized trials; it is recommended for adenocarcinomas and goblet-cell adenocarcinomasof stage III or higher, in analogy to the treatment of colorectal carcinoma.

Appendectomy in endometriosis: an update on surgical indications and management of uncommon diseases

PURPOSE OF REVIEW

Abnormal appendiceal disease is commonly encountered following an appendectomy when performed in patients with endometriosis. Appendiceal endometriosis is the most notable finding and can affect up to 39% of patients with endometriosis. Despite this knowledge, guidelines for performing an appendectomy have not been formally established. In this article, we review the surgical indications for an appendectomy at the time of endometriosis surgery and discuss the management of other diseases that may be encountered following the histopathologic evaluation of an excised appendix.

RECENT FINDINGS

Removal of the appendix in patients with endometriosis contributes to optimal surgical management. Relying on abnormal appendiceal appearance for removal may leave endometriosis-affected appendices. For this reason, utilizing risk factors to guide surgical management is essential. Common appendiceal diseases are sufficiently managed with appendectomy. Uncommon diseases may require further surveillance.

SUMMARY

Emerging data in our field support the performance of an appendectomy at the time of endometriosis surgery. Guidelines for performing a concurrent appendectomy should be formalized to encourage preoperative counselling and management for patients with risk factors for appendiceal endometriosis. Abnormal diseases is frequently encountered after appendectomy in the setting of endometriosis surgery and further management is based on the histopathology of the specimen.

Appendiceal Endometriosis: A Comprehensive Review of the Literature

Objective: the purpose of this review was to evaluate the prevalence of appendiceal endometriosis and the safety of concomitant appendectomy in women with endometriosis or pelvic pain. Materials and Methods: We searched the electronic databases Medline (PubMed), Scopus, Embase, and Web of Science (WOS). The search was not subject to any limitation in terms of time or method. The primary research question was: what is the prevalence of appendiceal endometriosis? The secondary research question was: is it safe to perform appendectomy during surgery for endometriosis? Publications that reported data about appendiceal endometriosis or appendectomy in women with endometriosis were reviewed regarding the inclusion criteria. Results: We found 1418 records. After review and screening, we included 75 studies published between 1975 and 2021. With regard to the first question of the review, we found 65 eligible studies and divided these into the following two categories: (a) endometriosis of the appendix presenting as acute appendicitis, and (b) endometriosis of the appendix as an incidental finding in gynecological surgery. Forty-four case reports described appendiceal endometriosis in women who were admitted for the treatment of pain in the right-sided lower abdomen. Endometriosis of the appendix was observed in 2.67% (range, 0.36-23%) of women who were admitted due to acute appendicitis. In addition, appendiceal endometriosis was an incidental finding during gynecological surgery in 7.23% of cases (range, 1-44.3%). With regard to the second question of the review, which was the safety of appendectomy in women with endometriosis or pelvic pain, we found 11 eligible studies. Reviewed cases had no significant intraoperative or follow-up complications during the 12 weeks. Conclusion: Based on the reviewed studies, coincidental appendectomy appears reasonably safe and was associated with no complications in the cases reviewed for the present report.

Transfusion of stored autologous blood in patients with low-grade pseudomyxoma peritonei: A retrospective analysis of its safety and outcome

Background

Pseudomyxoma peritonei is a rare disease that presents as a malignant tumor on the peritoneal surface. Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy is the standard treatment for this disease and frequently requires a red blood cell transfusion. However, due to the limited collection and supply of allogeneic blood, surgical treatment may be delayed due to inadequate preparation of allogeneic blood in the course of clinical treatment. This study aimed to evaluate the safety and efficacy of transfusion of stored autologous blood in patients with low-grade pseudomyxoma peritonei.

Methods

Pseudomyxoma peritonei patients who received cytoreductive surgery combined with heat-infused peritoneal chemotherapy were divided into two groups: transfusion of allogeneic blood and transfusion of stored autologous blood. A comparison of the differences in multiple factors between the two groups was performed, including tumor recurrence, survival time, hemoglobin and hematocrit levels, coagulation function (prothrombin time, activated partial thromboplastin time, and fibrinogen), total hospital stay duration, and incidence of serious adverse events after surgery.

Results

Propensity scores matching analysis yielded 34 patients with allogeneic blood transfusion and 34 patients with stored autologous blood transfusion. Comparison analysis did not show statistical differences in several factors, including age, tumor grade, tumor recurrence rate after surgery, etc., between the two groups. The cytoreductive degree was considered an independent risk factor for tumor recurrence. The pseudomyxoma peritonei patients in the autologous transfusion group had a higher 5-year survival rate and a longer survival time. Moreover, transfusion of stored autologous blood did not increase the rate of tumor recurrence, or the total hospital stay duration after surgery, the hemoglobin level and coagulation function were well stabilized within 24 h after surgery, and there was a low incidence of serious adverse events.

Conclusion

The clinical application of transfusion of stored autologous blood in pseudomyxoma peritonei patients is safe and effective.

Neurogenic Appendicitis: A Reappraisal of the Clinicopathological Features and Pathogenesis

In 1921; Masson and Maresch first coined the term “neurogenic appendicitis (NA)” to describe “neuroma-like” lesions in the appendix. To date, our knowledge about NA is limited; therefore, we conducted a comprehensive analysis of the literature (1921 to 2020) to examine the clinicopathological features of NA. We also addressed the pathophysiology of acute abdominal pain and fibrosis in this entity. We performed a meta-analysis study by searching the PubMed database, using several keywords, such as: “appendix,” “neurogenic,” “obliterative,” “neuroma,” “fibrous obliteration,” “appendicopathy,” and “appendicitis.” Our study revealed that patients with NA usually present clinically with features of acute appendicitis, bud2t they have grossly unremarkable appendices. Histologically, the central appendiceal neuroma was the most common histological variant of NA, followed by the submucosal and intramucosal variants. To conclude, NA represents a form of neuroinflammation. The possibility of NA should be considered in patients with clinical features of acute appendicitis who intraoperatively show a grossly unremarkable appendix. Neuroinflammation and neuropeptides play roles in the development of pain and fibrosis in NA.

Crohn Disease Infrequently Affects the Appendix and Rarely Causes Granulomatous Appendicitis

Data from previous studies suggest Crohn disease of the appendix accounts for ∼25% of granulomatous appendicitis cases. However, we have found that granulomatous inflammation in appendectomy specimens rarely heralds Crohn disease. We suspect that appendiceal involvement by Crohn disease is uncommon, even when patients have severe ileocolonic inflammation. We performed this study to determine the prevalence and nature of appendiceal inflammation among patients with Crohn disease. We reviewed 100 ileocolic specimens with strictures and fistulizing Crohn disease for the nature and distribution of inflammatory changes in the appendix and compared them with 100 appendices on colectomy specimens from age-matched and sex-matched patients with ulcerative colitis. We also evaluated 27 additional cases of granulomatous appendicitis in appendectomy specimens to determine the frequency with which this finding represented Crohn disease. The appendix was usually normal (26%) or showed fibrous obliteration (50%) in ileocolic resection specimens from patients with Crohn disease. Mucosal inflammation was much less common in appendices from patients with Crohn disease than ulcerative colitis (6% vs. 28%, P<0.0001); only 4 cases contained epithelioid granulomata, 3 showed mural fibrosis and lymphoid aggregates, and 10 displayed only periappendiceal inflammation. None of the patients with granulomatous appendicitis in appendectomy specimens had, or developed, evidence of Crohn disease. We conclude that Crohn disease infrequently affects the appendix. Interval appendectomy and infection are more important considerations when appendectomy specimens feature granulomatous inflammation and/or mural lymphoid aggregates, especially if there is no history of idiopathic inflammatory bowel disease.

Parasites in surgically removed appendices as a neglected public health concern: a systematic review and meta-analysis

The role of various parasitic infections in the occurrence of appendicitis is illustrated through cases recorded all over the world. The purpose of the current study was to estimate the global prevalence of parasite infestation (other than E. vermicularis) in appendectomy specimens.In the setting of the PRISMA guidelines, multiple databases (Science Direct, Scopus, Web of Science, PubMed, and Google Scholar) were explored in articles published until 28 September 2020. Totally, 62 studies (106 datasets) with 77, 619 participants were included in the analysis.The pooled prevalence of parasites in appendectomy samples was as follows; 0.012% (95% CI; 0.004-0.025) for Ascaris lumbricoides, 0.004% (95% CI; 0.001-0.009) for Trichuris trichiura, 0.025% (95% CI; 0.007-0.052) for Schistosoma mansoni, 0.002% (95% CI; 0.001-0.005) for Taenia spp., 0.061% (95% CI; 0.020-0.122) for Entamoeba histolytica and 0.034% (95% CI; 0.018-0.056) for Giardia lamblia.Our results demonstrated that the risk of appendicitis may increase in the presence of helminth and protozoan infections. As such, the most cases of parasites in appendectomy specimens were reported in developing countries. Regular screening plans for diagnosis, treatment and prevention are needed for prevention of parasitic infection as well as parasitic associated appendicitis, especially in endemic regions of the world.

Acute Appendicitis Secondary to Appendiceal Endometriosis

Endometriosis in the vermiform appendix is a rare condition that affects women of childbearing age. The clinical picture can simulate inflammatory acute abdominal pain, especially acute appendicitis. Laboratory and imaging tests may assist in the diagnosis but are not conclusive. This article reports a case of acute appendicitis caused by appendiceal endometriosis for which laparoscopic appendectomy and diagnostic confirmation were performed after histopathological analysis.

Routine Histopathological Evaluation After Appendectomy: Is It Necessary? A Systematic Review

Acute appendicitis is one of the most common reasons for acute abdominal pain. Fecaliths and lymphoid hyperplasia are the usual etiology of acute appendicitis, however, other unusual causes can also not be neglected which can be parasitic infections, benign or malignant lesions. Due to substantial lab costs and limited resources, the policy of routine histopathological examination (HPE) of appendectomy samples is being questioned.

PubMed, PubMed Central (PMC), and Google Scholar were used to look for relevant published studies. The following keywords were used both alone and in combination: “Acute appendicitis” and “routine histopathological examination”. Fifteen articles were selected for final review that collectively had 57,524 cases. All these studies included in this systematic review are peer-reviewed.

Based on the reviewed articles, it was found that though the probability of unusual findings in a patient of acute appendicitis is less but it is still significant and if found, often results in a change of management plan of the patient.

Therefore, it is recommended to perform a routine histopathological examination of all appendectomy specimens to rule out unusual pathologies.

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.

The neglected role of Enterobius vermicularis in appendicitis: A systematic review and meta-analysis

Although the main cause of appendicitis is unclear, infection with Enterobius vermicularis is suggested as a neglected risk factor. Since, there is no comprehensive analysis to estimate the prevalence of E. vermicularis in appendicitis; therefore, we conducted a global-scale systematic review and meta-analysis study to estimate the prevalence of E. vermicularis infection in appendicitis cases. PubMed, Scopus, Web of Science and Google Scholar databases were systematically searched for relevant studies published until 15 August 2019. Pooled prevalence of E. vermicularis infection was estimated using the random effects model. Data were classified based on the continents and countries. Moreover, subgroup analyses regarding the gender, the human development index (HDI), and income level of countries were also performed. Fifty-nine studies involving 103195 appendix tissue samples belonging to the individuals of appendicitis were included. The pooled prevalence of E. vermicularis infection was (4%, 95%CI, 2–6%), with the highest prevalence (8%, 95% CI: 0–36%) and lowest prevalence (2%, 95% CI: 1–4%) in Africa and Americas continents, respectively. With respect to countries, the lowest and highest prevalence rates were reported from Venezuela (<1%, 95% CI: 0–1%) and Nigeria (33%, 95% CI: 17–52%), respectively. Indeed, a higher prevalence was observed in females, as well as in countries with lower levels of income and HDI. Our findings indicate the relatively high burden of E. vermicularis infection in appendicitis cases. However, our findings suggest the great need for more epidemiological studies to depth understand overlaps between E. vermicularis infection and appendicitis in countries with lower HDI and income levels.

Neuroma of the appendix, a rare cause of appendicitis and an important reason for close follow-up

Acute appendicitis is the most common surgical pathology worldwide, frequently, the patient history and clinical examination are so similar to other appendicular pathologies that preoperative diagnosis is almost impossible for the medical team. Neuroma of the appendix is a rare tumor of neural origin that usually resembles the symptoms of acute appendicitis. Pathology along with close follow-ups are key, as the diagnosis is based on the presence of nerve neuronal cells in the appendicular lumen. Surgical treatment is recommended due to the possibility of malignancy. We present a case of a 32-year-old male patient who presented with symptoms of acute abdomen, surgery was performed and appendectomy was completed. Neuroma of the appendix was the final diagnosis.

Surgical Infections in Low- and Middle-Income Countries: A Global Assessment of the Burden and Management Needs

Background: The burden of surgical infections in low- and middle-income countries (LMICs) remains poorly defined compared with high-income countries. Although there are common infections necessitating surgery prevalent across the world, such as appendicitis and peptic ulcer disease, other conditions are more localized geographically. To date, comprehensive assessment of the burden of surgically treatable infections or sequelae of surgical infections in LMICs is lacking. Methods: We reviewed the literature to define the burden of surgical infections in LMICs and characterize the needs and challenges of addressing this issue. Results: Surgical infections comprise a broad range of diseases including intra-abdominal, skin and soft tissue, and healthcare-associated infections and other infectious processes. Treatment of surgical infections requires a functional surgical ecosystem, microbiology services, and appropriate and effective antimicrobial therapy. Systems must be developed and maintained to evaluate screening, prevention, and treatment strategies. Solutions and interventions are proposed focusing on reducing the burden of disease, improving surveillance, strengthening antibiotic stewardship, and enhancing the management of surgical infections. Conclusions: Surgical infections constitute a large burden of disease globally. Challenges to management in LMICs include a shortage of trained personnel and material resources. The increasing rate of antimicrobial drug resistance, likely related to antibiotic misuse, adds to the challenges. Development of surveillance, infection prevention, and antimicrobial stewardship programs are initial steps forward. Education is critical and should begin early in training, be an active process, and be sustained through regular programs.

Impact of routine histopathological examination of appendectomy specimens on patient management: a study of 4012 appendectomy specimens

Objectives

For a suspected diagnosis of acute appendicitis, appendectomy is one of the most common emergency abdominal operations performed. However, the need for routine histopathological examination (HPE) of all appendectomy specimens has recently been questioned. The aim of this study was to assess whether a routine HPE of appendectomy specimens is needed and whether routine HPE has an impact on further management of patients.

Material and Methods

From January 2009 to June 2017, all histopathology reports of 4012 consecutive appendectomy specimens for a clinical suspicion of acute appendicitis were retrospectively analyzed in two university hospitals.

Results

Out of the 4012 cases, 3530 (88%) patients showed findings consistent with acute appendicitis on HPE. Perforation rate was 5.8% and was significantly higher in male patients (p <0.001) and higher in the > 30 years age group (p= 0.024). Negative appendectomy rate was 5.6% and was significantly higher in female patients (p <0.001). There were 256 (6.4%) patients who demonstrated unusual findings in their HPE, which included chronic appendicitis (n= 207; 5.2%) patients, Enterobius vermicularis (n= 14), Schistosoma (n= 8), Crohn's disease (n= 1), neuroma (n= 10), carcinoid tumour (n= 5) and mucinous cystadenoma (n= 5), mucocele (n= 4) and mucinous cystadenocarcinoma (n= 2).

Conclusion

HPE of the appendix does not only confirm the diagnosis of acute appendicitis, but also detects other unusual diagnoses that may have an impact on a patient's management. A number of patients with unusual histopathological findings require anti-helmentic treatment, colectomy, gastroenterology follow-up or periodic surveillance. Hence, all appendectomy specimens must be submitted for routine HPE.

Mucinous appendiceal neoplasms: classification, imaging, and HIPEC

Recent advances, specifically cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), offer advantages compared to the traditional therapeutic approach of systemic chemotherapy in the treatment of peritoneal carcinomatosis from mucinous appendiceal neoplasms (MAN). This review provides an up-to-date, comprehensive summary of the histologic classification of MAN, reviews common imaging findings of mucoceles and pseudomyxoma peritonei, and describes the radiologist's role in the multidisciplinary care team in quantifying disease and in helping select patients for definitive surgery.