Incidental diagnosis of primary appendiceal signet-ring cell adenocarcinoma after appendectomy for acute appendicitis: a case report.

Introduction: Appendiceal signet-ring cell adenocarcinoma (ASCA) is rare and more aggressive in malignant appendiceal neoplasms. The presentation can be appendicitis, which is lack of specific symptom and makes early diagnosis difficult. There is no effective surveillance. Prognosis largely relies on timely detection. We report a case of ASCA incidentally diagnosed through pathological examination after appendectomy for appendicitis. Case presentation: The patient presented to our department with a progressive right lower quadrant abdominal pain lasting for 3 days. Physical examination revealed rigidity, tenderness, and rebound tenderness on the right lower quadrant. A computed tomography scan showed a thickened, inflamed appendix with peri-appendiceal fat stranding without noticeable appendiceal mass at initial evaluation. The diagnosis was considered acute appendicitis, and an appendectomy was performed. The appendix was inflamed, gangrenous and perforated, and no mass was found during the surgery. Surgical specimen was sent for physiological examination, which incidentally detected signet-ring cell in H&E staining. And immunohistochemistry confirmed the diagnosis of ASCA with small amount of neuroendocrine neoplasms. Conclusion: Early diagnosis of ASCA can incidentally be made on pathological specimen following appendectomy for appendicitis. A routine pathological examination should be emphasized, and appendectomy may not be the endpoint of the treatment. Hemicolectomy and adjuvant therapy might ensue upon the diagnosis of appendiceal neoplasm. The poor prognosis of ASCA makes a timely diagnosis significant. Basic research is promising to unravel the molecular mechanisms of pathogenesis, finding typical tumor markers for screening and novel effective therapies for advanced cases.

Mucinous neoplasm of the appendix: A case report and review of literature.

BACKGROUND: Appendiceal mucinous neoplasms (AMNs), although not classified as rare, are relatively uncommon tumors most often discovered incidentally during colorectal surgery. Accurate identification of AMNs is difficult due to non-specific symptoms, overlapping tumor markers with other conditions, and the potential for misdiagnosis. This underscores the urgent need for precision in diagnosis to prevent severe complications. CASE SUMMARY: This case report describes the unexpected discovery and treatment of a low-grade AMN (LAMN) in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma (AC). Preoperatively, non-specific gastrointestinal symptoms and elevated tumor markers masked the presence of AMN. The tumor, presumed to be an AMN peritoneal cyst intraoperatively, was confirmed as LAMN through histopathological examination. The neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile: Positive for Homeobox protein CDX-2, Cytokeratin 20, special AT-rich sequence-binding protein 2, and Mucin 2 but negative for cytokeratin 7 and Paired box gene 8. This profile aids in distinguishing appendiceal and ovarian mucinous tumors. Postoperative recovery was uncomplicated, and the patient initiated adjuvant chemotherapy for the colon AC. CONCLUSION: This case highlights the diagnostic complexity of AMNs, emphasizing the need for vigilant identification to avert potential complications, such as pseudomyxoma peritonei.

Colonoscopy in the diagnosis and management of appendiceal disease.

In this editorial, we comment on the article published in the recent issue of the World Journal of Gastrointestinal Endoscopy. We focused on the understanding of appendiceal disease, and the various options for diagnosis and treatment via endoscopy. Some factors affecting the diagnosis and management of appendiceal diseases are also discussed. The existence of any organ has its natural rationality, and the appendix is such a magical organ. A growing number of experts and scholars have gradually come to a consensus that the appendix is not a useless evolutionary relic. There are many lymphocytes and lymph nodes in the appendix wall, which has a strong immune function, and this function is particularly important for children and adolescents. Many intestinal probiotics in the appendix are very helpful for maintaining the balance of the intestinal flora. With the continuous progress of endoscopic technology, endoscopic treatment involving preservation of the appendix has shown great advantages over surgery. In the diagnosis of appendiceal inflammation and neoplasms, colonoscopy, endoscopic retrograde appendicography and choledochoscopy help assess conditions of the appendix. Endoscopic retrograde appendicitis therapy, abscess drainage under colonoscopy, fenestration of abscess under colonoscopy, and endoscopic or natural orifice transluminal endoscopic surgery resection of appendiceal neoplasms are safe and effective endoscopic treatments for appendiceal disease. New breakthroughs in the application of endoscopy in the appendix are expected to occur in the near future.

Phase 1 trial of same day cytology to guide the use of HIPEC.

Background: Peritoneal metastases from gastrointestinal or gynecologic malignancy are a prominent part of the natural history of these diseases. Peritoneal metastases, if not effectively treated, will result in a decreased survival and cause an impaired quality of life. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment specifically designed to combat peritoneal metastases. A group of patients who, from a theoretical perspective, may benefit from HIPEC are those patients with a positive peritoneal cytology. In order to identify these patients at the time of a surgical intervention, a same day cytology is to be performed. Materials and methods: The result of this test is to be available at or before the completion of the cancer resection. If the cytology is positive, the patient immediately becomes a candidate for HIPEC. The HIPEC will be of maximal value if a complete cytoreduction, as judged by the surgeon, has been possible. This phase 1 trial is to demonstrate that the Surgical Oncology Service, the Department of Pathology, the Pharmacy and the Operating Room personnel can co-ordinate a phase 1 protocol to successfully complete the same day cytology with an efficient delivery of HIPEC. A standardized plan for consent, cytology collection, preparation of the specimen, reading of the specimen, reporting the results in a timely manner facilitates the administration of HIPEC in peritoneal cytology positive patients. Dissemination: Successful completion of these requirements is a positive result for this study and allows for future protocols to be generated. Successful completion of the same day cytology phase 1 protocol will allow the efficacy, safety, and efficiency of this plan of patient management to be evaluated.

Appendiceal actinomycosis mimicking malignant tumor: a rare case report.

Introduction: Actinomycosis is an uncommon bacterial infection caused by Actinomyces bacteria that typically progresses slowly and leads to the formation of masses. Although it commonly affects the cervicofacial area, about 20% of cases occur in the abdominopelvic region. Because the disease can be mistaken for a tumour due to its infiltrative mass-like nature on imaging, over 90% of cases are only diagnosed following surgery and histological confirmation. This report describes a case of an appendicular mass, initially suspected to be a malignant tumour, but eventually diagnosed as appendiceal actinomycosis. Presentation of case: Upon initial presentation, a 53-year-old woman with type II diabetes mellitus and no prior surgical history, displayed abnormal appendiceal uptake during a PET-computed tomography (CT) scan conducted for a suspected spinal tumour. Colonoscopy did not indicate any notable observations, and the patient chose to defer immediate action. Several months later, a CT scan revealed an increased mass-like appearance of the appendix compared to the previous PET-CT scan. After multidisciplinary discussions, a right laparoscopic hemicolectomy was recommended due to suspected malignancy. However, histological staining on microscopy confirmed actinomycosis originating from the appendix. Discussion: Chronic appendicitis with radiologic features similar to appendiceal carcinoma, or abdominal masses located in the ileocecal area, in patients with or without a previous surgical history should raise suspicion of actinomycosis. Conclusion: Appendiceal actinomycosis should be considered in the differential diagnosis in the aetiology of chronic appendicitis mimicking appendiceal carcinoma. Awareness and accurate diagnosis of appendiceal actinomycosis can prevent unnecessary extended surgery as was performed in this case.

Fragmentation of Care in Patients with Peritoneal Metastases Undergoing Cytoreductive Surgery.

BACKGROUND: The delivery of multimodal treatment at a high-volume center is known to optimize the outcomes of gastrointestinal malignancies. However, patients undergoing cytoreductive surgery (CRS) for peritoneal metastases often must 'fragment' their surgical and systemic therapeutic care between different institutions. We hypothesized that this adversely affects outcomes. PATIENTS AND METHODS: Adults undergoing CRS for colorectal or appendiceal adenocarcinoma at our institution between 2016 and 2022 were identified retrospectively and grouped by care network: 'coordinated care' patients received exclusively in-network systemic therapy, while 'fragmented care' patients received some systemic therapy from outside-network providers. Factors associated with fragmented care were also ascertained. Overall survival (OS) from CRS and systemic therapy-related serious adverse events (SAEs) were compared across the groups. RESULTS: Among 85 (80%) patients, 47 (55%) had colorectal primaries and 51 (60%) received fragmented care. Greater travel distance [OR 1.01 (CI 1.00-1.02), p = 0.02] and educational status [OR 1.04 (CI 1.01-1.07), p = 0.01] were associated with receiving fragmented care. OS was comparable between patients who received fragmented and coordinated care in the colorectal [32.5 months versus 40.8 months, HR 0.95 (CI 0.43-2.10), p = 0.89] and appendiceal [31.0 months versus 27.4 months, HR 1.17 (CI 0.37-3.74), p = 0.55] subgroups. The frequency of SAEs (7.8% versus 17.6%, p = 0.19) was also similar. CONCLUSIONS: There were no significant differences in survival or SAEs based on the networks of systemic therapy delivery. This suggests that patients undergoing CRS at a high-volume center may safely receive systemic therapy at outside-network facilities with comparable outcomes.

Role of colectomy in the management of appendiceal tumors: a retrospective cohort study.

BACKGROUND: Appendiceal tumors represent a range of histologies that vary in behavior. Recommendations for treatment with appendectomy versus right hemicolectomy (RHC) for different tumor types are evolving and sometimes conflicting. This study sought to characterize variation in the United States around surgical treatment of major appendiceal tumor types over time and describe differences in outcomes based on procedure. METHODS: Patients diagnosed with appendiceal goblet cell adenocarcinoma (GCA), mucinous adenocarcinoma, neuroendocrine neoplasm (NEN), or non-mucinous adenocarcinoma from 2004-2017 were identified in the National Cancer Database. Trends in RHC over time and predictors of RHC were identified. Surgical outcomes for each histologic type and stage were compared. RESULTS: Of 18,216 patients, 11% had GCAs, 34% mucinous adenocarcinoma, 31% NENs, and 24% non-mucinous adenocarcinoma. Rate of RHC for NEN decreased from 68% in 2004 to 40% in 2017 (p = 0.008) but remained constant around 60-75% for other tumor types. Higher stage was associated with increased odds of RHC for all tumor types. RHC was associated with higher rate of unplanned readmission (5% vs. 3%, p < 0.001) and longer postoperative hospital stay (median 5 days vs. 3 days, p < 0.001). On risk-adjusted analysis, RHC was significantly associated with increased survival versus appendectomy for stage 2 disease of all tumor types (HRs 0.43 to 0.63) and for stage 1 non-mucinous adenocarcinoma (HR = 0.56). CONCLUSIONS: Most patients with appendiceal tumors undergo RHC, which is associated with increased readmission, longer length of stay, and improved survival for stage 2 disease of all types. RHC should be offered selectively for appendiceal tumors.

Incidence of appendiceal neoplasms in appendectomy patients.

BACKGROUND: Non-operative management has been suggested as a therapy for uncomplicated appendicitis. Notwithstanding, the risk of missing an appendiceal tumor must be considered, being the surgical piece crucial to rule out neoplasms. Therefore, we aim to determine the incidence of appendiceal neoplasms in patients with acute appendicitis, tumor types and the importance of the anatomopathological study of the surgical piece. STUDY DESIGN: Retrospective study in which we described patients who underwent emergent appendectomy with histopathological findings of appendiceal neoplasms from January 2012 to September 2018. Descriptive analysis included demographic variables, diagnostic methods, and surgical techniques. RESULTS: 2993 patients diagnosed with acute appendicitis who underwent an emergency appendectomy. 64 neoplasms of the appendix were found with an incidence of 2,14%. 67.2% were women, the mean age was 46,4 years (± 19.5). The most frequent appendiceal neoplasms were neuroendocrine tumors (42,2%), followed by appendiceal mucinous neoplasms (35,9%), sessile serrated adenomas (18,8%), and adenocarcinomas (3,1%). In 89,1% of the cases, acute appendicitis was determined by imaging, and 14% of cases were suspected intraoperatively. Appendectomy was performed in 78,1% without additional procedures. CONCLUSIONS: Appendiceal tumors are rare and must be ruled out in patients with suspected acute appendicitis. The incidence of incidental neoplasms is higher in this study than in the previously reported series. This information must be included in decision-making when considering treatment options for acute appendicitis.

Apendicitis aguda por intususcepción secundaria a endometriosis. Reporte de caso / Acute appendicitis due to intussusception secondary to endometriosis. Case report

Introducción. La intususcepción del apéndice corresponde a su invaginación en el ciego. Existen varias causas, pero la endometriosis ha sido informada pocas veces. Aunque el diagnóstico se debe sospechar clínicamente, por lo general su causa solo se determina en el intraoperatorio, donde se deben tener en cuenta causas oncológicas que requieran una resección amplia. Caso clínico. Mujer de 21 años que consultó por dolor abdominal agudo generalizado. Se practicó una tomografía computarizada de abdomen, observando una intususcepción del apéndice en el ciego, estriación de la grasa pericecal y adenomegalias. Se realizó laparoscopia diagnóstica encontrando intususcepción casi completa del apéndice cecal, de aspecto neoplásico. Se convirtió a laparotomía para proceder a hemicolectomía derecha, con vaciamiento ganglionar y anastomosis del íleon al colon transverso. Discusión. La sospecha clínica de intususcepción debe corroborarse mediante ecografía, tomografía o estudios baritados. El tratamiento siempre es quirúrgico, como en el caso de nuestra paciente, quien evolucionó de forma adecuada y continuó asintomática después de un año de seguimiento. Conclusión. El diagnóstico temprano de la intususcepción permite realizar tratamientos quirúrgicos menos agresivos y disminuye el riesgo de filtración de la anastomosis. Se debe tener en cuenta el diagnóstico de endometriosis como posible causa. Se debe realizar el manejo complementario por parte de ginecología.

Introduction. The intussusception of the appendix corresponds to its invagination in the cecum. There are several causes, endometriosis being rarely reported. Although the diagnosis must be suspected clinically, its cause is generally only determined intraoperatively, where oncological causes that require extensive resection must be taken into account. Clinical case. A 21-year-old woman who consulted due to acute generalized abdominal pain, an abdominal tomography was performed, finding an intussusception of the appendix in the cecum, striation of pericecal fat, and lymph nodes. A diagnostic laparoscopy was performed, finding almost complete intussusception of the appendix, with a neoplastic appearance. She was converted to laparotomy to perform a right hemicolectomy, with lymph node dissection and ileal to transverse anastomosis. Discussion. Clinical suspicion of intussusception should be confirmed by ultrasound, abdominal tomography, or barium studies. Treatment is always surgical, as in the case of our patient, who evolved adequately and remained asymptomatic after one year of follow-up. Conclusion. Early diagnosis of intussusception allows for less aggressive surgical treatment and decreases the risk of anastomosis leakage. The diagnosis of endometriosis should be taken into account as a possible cause. Complementary management by gynecologists should be performed.

Low-grade appendiceal mucinous neoplasm with puffer ball-like appearance: A case report.

We report a case of ruptured low-grade appendiceal mucinous neoplasm with an impressive toy puffer ball-like appearance on magnetic resonance imaging. A 79-year-old woman with lower abdominal pain underwent computed tomography scanning, revealing a 6-cm mass in the right lower abdomen. T2-weighted images showed a radial low-signal structure in the central area of the mass, which was presumed to be fibrotic. Pathology confirmed ruptured low-grade appendiceal mucinous neoplasm. The rupture point was at the tip of the appendix, coinciding with the center of radial fibrosis. The unique morphology of the puffer ball-like appearance in this case may be a characteristic of low-grade appendiceal mucinous neoplasms.

Peritoneal metastases from primary appendiceal and colorectal carcinomas demonstrate distinct molecular identities on comprehensive tumor analysis.

BACKGROUND AND OBJECTIVES: Published data comparing peritoneal metastases from appendiceal cancers (pAC) and colorectal cancers (pCRC) remain sparse. We compared pAC and pCRC using comprehensive tumor profiling (CTP). METHODS: CTP was performed, including next-generation sequencing and analysis of copy number variation (CNV), microsatellite instability (MSI) and tumor mutational burden (TMB). RESULTS: One hundred thirty-six pAC and 348 pCRC samples underwent CTP. The cohorts' age and gender were similar. pCRC demonstrated increased pathogenic variants (PATHs) in APC (48% vs. 3%, p < 0.01), ARID1A (12% vs. 2%, p < 0.01), BRAF (12% vs. 2%, p < 0.01), FBXW7 (7% vs. 2%, p < 0.01), KRAS (52% vs. 41%, p < 0.05), PIK3CA (15% vs. 2%, p < 0.01), and TP53 (53% vs. 23%, p < 0.01), and decreased PATHs in GNAS (8% vs. 31%, p < 0.01). There was no difference in CNV, fusion rate, or MSI. Median TMB was higher in pCRC (5.8 vs. 5.0 mutations per megabase, p = 0.0007). Rates of TMB-high tumors were similar (pAC 2.1% vs. pCRC 9.0%, p = 0.1957). pCRC had significantly more TMB-high tumors at lower thresholds. CONCLUSIONS: Despite a reduced overall TMB, pAC demonstrated mutations distinct from those seen in pCRC. These may serve as discrete biomarkers for future study.

Appendiceal schwannoma - report of a case and literature review.

Appendiceal tumours encompass a wide spectrum of differential diagnoses and frequently present with clinical features of appendicitis. We report the case of a 43-year-old woman who presented with epigastric pain, dyspepsia and bloating. An atypical right para-iliac mass was detected on abdominal ultrasound, and computed tomography (CT) identified an appendiceal tumour. The tumour subtype remained indeterminate following Gallium-68 Dotatate positron emission tomography (PET); however, an appendiceal neuroendocrine tumour was suspected. Surgical resection with laparoscopic en bloc appendicectomy and limited caecectomy was performed, and histopathological assessment confirmed an appendiceal schwannoma. The report is followed by a review of the literature. To our knowledge, there have been fourteen reported cases of appendiceal schwannoma. The preoperative diagnosis can be challenging and appendiceal schwannoma had not been suspected in any of the reported cases, while a suspected diagnosis of neuroendocrine tumour or gastrointestinal stromal tumour was common. Definitive diagnosis requires immunohistochemical assessment and S100 is the hallmark. No personal or family history of underlying neurofibromatosis (NF) type 1 or type 2 has been reported to date. As for other gastrointestinal schwannomas, complete surgical resection is the recommended treatment for appendiceal schwannoma. Following this, despite lack of long-term follow-up, no cases of recurrence have been reported thus far.

The diagnostic value of KRAS gene mutation in appendiceal adenocarcinoma / 中国医师杂志

Objective:To analyze the mutation characteristics of Kirsten rat sarcoma virus oncogene homology (KRAS) gene in patients with appendiceal adenocarcinoma and its relationship with the activity of Ras Raf Mitogen activated protein kinase/extracellular regulated protein kinase (MAPK/ERK) signaling pathway.Methods:A total of 41 patients with appendiceal adenocarcinoma who were treated in the Lishui Central Hospital from January 2014 to January 2020 were selected as the observation group, and 50 patients with Appendicitis who were operated at the same time were randomly selected as the control group. Clinical and follow-up data were collected, and the mutation of the KRAS gene in the patient′s tissue was measured using the snapshot method. The expression of key proteins in the MAPK/ERK signaling pathway in cancer tissue was measured using Western blotting (WB) assay. We compared the clinical characteristics and prognosis of patients with KRAS mutation and non KRAS mutation appendiceal adenocarcinoma.Results:The KRAS gene mutation rate in the observation group was higher than that in the control group (41.5% vs 10.0%), and the expression levels of p-ARAF/ARAF, p-MEK1/MEK1, and p-ERK1/ERK1 proteins were also higher than those in the control group. The differences between the groups were statistically significant (all P<0.05). The protein expression levels of p-ARAF/ARAF, p-MEK1/MEK1, p-ERK1/ERK1 in KRAS mutation patients in the observation group were significantly higher than those in non KRAS mutation patients. The proportion of stage IV, positive rates of carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199 and CA125 in KRAS mutation patients were higher than those in non KRAS mutation patients, and the survival time and progression free survival time were shorter than those in non KRAS mutation patients, with statistical significance (all P<0.05). Conclusions:The mutation rate of KRAS in appendix adenocarcinoma is high, and the activation of MAPK/ERK signaling pathway caused by KRAS mutation may play a role in the pathogenesis of appendix adenocarcinoma, which has the value of in-depth research.

Prevalence of Neuroendocrine Tumours (NET) in Patients Undergoing Appendicectomy for Acute Appendicitis: A Tertiary Care Study.

Introduction Acute appendicitis is one of the common causes of acute abdomen in adults, which is managed widely with appendicectomy. Neuroendocrine tumours are the most common appendiceal tumours diagnosed incidentally on appendicectomy specimens.  Methods  Demographic data, presenting complaints, indications for appendicectomy, and the histology findings based on histopathological reports of the patients who have undergone appendicectomy for appendicitis at surgical units of Teaching Hospital, Jaffna, from 1st of January 2019 to 31st of December 2022 were retrospectively analyzed.  Results Of the 1341 histopathology reports, 0.2% (n=3) were neuroendocrine tumours (NET). The mean age of the patients with NET was 48.6, and 66.6% of them were females. All three NETs identified in appendicectomy specimens were well differentiated and smaller than 2 cm. All three had negative resection margins and were managed only with appendicectomy.  Conclusion  NETs of the appendix are the commonest appendiceal neoplasms. The majority of them are diagnosed incidentally in appendicectomy specimens. Surgical management of the tumours is either by appendicectomy or hemicolectomy, which depends mainly on tumor size. Surgical decisions should be tailor-made to the patients based on multi-disciplinary team decisions.

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

SUMMARY 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.

Mucocele of the appendix: what to expect.

Mucoceles of the appendix are rare and can have quite variable imaging and clinical presentations, sometimes mimicking an adnexal mass. The underlying cause can be neoplastic or non-neoplastic. The typical imaging appearance of a mucocele of the appendix is that of a cystic structure with a tubular morphology. This structure is defined by having a blind-ending and being contiguous with the cecum. Radiologists should be familiar with key anatomical landmarks and with the various imaging features of mucoceles of the appendix, in order to provide a meaningful differential diagnosis of a lesion in the right lower abdominal quadrant. In addition, a neoplastic mucocele can rupture, resulting in pseudomyxoma peritonei, which will change the prognosis dramatically. Therefore, prompt diagnostic imaging is crucial.

Mucoceles do apêndice são raras e podem ter uma apresentação clínica e imagiológica bastante variável, por vezes mimetizando patologia anexial. As causas subjacentes podem ser neoplásicas ou não neoplásicas. O aspecto de imagem típico de mucoceles do apêndice é o de uma estrutura de natureza cística com morfologia tubular. Esta estrutura deverá terminar "em fundo cego" e ser contígua com o ceco. Os radiologistas devem estar familiarizados com os pontos anatômicos de referência e com as diferentes características imagiológicas de mucoceles do apêndice, de modo a fornecer um adequado diagnóstico diferencial de uma lesão localizada no quadrante abdominal inferior direito. Para além disso, uma mucocele neoplásica pode sofrer ruptura, resultando em pseudomixoma peritoneal, o que altera drasticamente o prognóstico. Assim, o diagnóstico por imagem em tempo útil é crucial.

Management of incidentally discovered appendiceal neuroendocrine tumors after an appendicectomy.

Appendiceal neuroendocrine tumors (aNETs) are an uncommon neoplasm that is relatively indolent in most cases. They are typically diagnosed in younger patients than other neuroendocrine tumors and are often an incidental finding after an appendectomy. Although there are numerous clinical practice guidelines on management of aNETs, there is continues to be a dearth of evidence on optimal treatment. Management of these tumors is stratified according to risk of locoregional and distant metastasis. However, there is a lack of consensus regarding tumors that measure 1-2 cm. In these cases, some histopathological features such as size, tumor grade, presence of lymphovascular invasion, or mesoappendix infiltration must also be considered. Computed tomography or magnetic resonance imaging scans are recommended for evaluating the presence of additional disease, except in the case of tumors smaller than 1 cm without additional risk factors. Somatostatin receptor scintigraphy or positron emission tomography with computed tomography should be considered in cases with suspected residual or distant disease. The main point of controversy is the indication for performing a completion right hemicolectomy after an initial appendectomy, based on the risk of lymph node metastases. The main factor considered is tumor size and 2 cm is the most common threshold for indicating a colectomy. Other factors such as mesoappendix infiltration, lymphovascular invasion, or tumor grade may also be considered. On the other hand, potential complications, and decreased quality of life after a hemicolectomy as well as the lack of evidence on benefits in terms of survival must be taken into consideration. In this review, we present data regarding the current indications, outcomes, and benefits of a colectomy.

Mucocele of the appendix: what to expect / Mucocele do apêndice: o que esperar

Abstract Mucoceles of the appendix are rare and can have quite variable imaging and clinical presentations, sometimes mimicking an adnexal mass. The underlying cause can be neoplastic or non-neoplastic. The typical imaging appearance of a mucocele of the appendix is that of a cystic structure with a tubular morphology. This structure is defined by having a blind-ending and being contiguous with the cecum. Radiologists should be familiar with key anatomical landmarks and with the various imaging features of mucoceles of the appendix, in order to provide a meaningful differential diagnosis of a lesion in the right lower abdominal quadrant. In addition, a neoplastic mucocele can rupture, resulting in pseudomyxoma peritonei, which will change the prognosis dramatically. Therefore, prompt diagnostic imaging is crucial.

Resumo Mucoceles do apêndice são raras e podem ter uma apresentação clínica e imagiológica bastante variável, por vezes mimetizando patologia anexial. As causas subjacentes podem ser neoplásicas ou não neoplásicas. O aspecto de imagem típico de mucoceles do apêndice é o de uma estrutura de natureza cística com morfologia tubular. Esta estrutura deverá terminar "em fundo cego" e ser contígua com o ceco. Os radiologistas devem estar familiarizados com os pontos anatômicos de referência e com as diferentes características imagiológicas de mucoceles do apêndice, de modo a fornecer um adequado diagnóstico diferencial de uma lesão localizada no quadrante abdominal inferior direito. Para além disso, uma mucocele neoplásica pode sofrer ruptura, resultando em pseudomixoma peritoneal, o que altera drasticamente o prognóstico. Assim, o diagnóstico por imagem em tempo útil é crucial.

A case report of appendiceal adenocarcinoma without gastrointestinal evidence mimicking primary ovarian cancer.

Metastatic tumours to the ovary comprise 10-25% of ovarian malignancies and may originate from various primary sites. Here, the case of a 49-year-old female patient who presented with periumbilical nodules and abdominal bloating is reported. She was found to have bilateral ovarian tumours with peritoneal carcinomatosis and ascites. Primary ovarian cancer was suspected while no contributory gastrointestinal lesion was detected by imaging studies and endoscopic examinations. Three cycles of neoadjuvant chemotherapy were administered, followed by interval debulking surgery. Appendiceal cancer was highly suspected based on analysis of a frozen section obtained during surgical debulking. Following the pathology investigation, the patient was finally diagnosed with primary appendiceal adenocarcinoma. She underwent chemotherapy comprising irinotecan and fluorouracil. Due to disease progression despite several chemotherapy regimens, the patient declined further treatment and was lost to follow-up 1 year after the debulking surgery. Metastatic tumours to the ovary may mimic primary ovarian cancers and often present with nonspecific manifestations. Therefore, meticulous exploration of the primary site is warranted if the diagnosis is clinically suspicious.