Management of an unexpected appendiceal neoplasm

Active surveillance for low-grade appendiceal mucinous neoplasm (LAMN)

Objectives

Due to the scarcity of low-grade appendiceal mucinous neoplasm (LAMN), there is an absence of systematized guidelines concerning its management, especially after incidental finding on an appendiceal specimen. In this study, we evaluate the active surveillance (AS) strategy adopted for a series of patients diagnosed with LAMN on resection specimens who were considered to have a low risk of pseudomyxoma progression.

Methods

Thirty patients were included between April 2014 and July 2021, with a female majority and a median follow-up period of 3.1 years. The inclusion criteria were as follows: LAMN diagnosis on appendiceal specimens, confirmed in an expert center, limited extra-appendiceal mucin resected and localized around the appendix, normal biology (CEA, CA199, CA125) and normal abdominopelvic MRI. AS included physical exam (trocar scar), biology and MRI, 6 months postoperatively, then yearly for 10 years.

Results

As an initial surgery, 77 % had an appendectomy as their initial intervention, 17 % had a cecectomy, and 6 % had a right colectomy. After follow-up, 87 % of patients showed no sign of disease progression by MRI, while 13 % progressed to PMP. MRI performed in the first postoperative year predicted the disease prognosis in 97 % of patients.

Conclusions

The AS strategy, based on MRI, is a valid option after incidental LAMN diagnosis.

Low-Grade Appendiceal Mucinous Neoplasm Causing Equivocal Appendicitis: A Case Report

Appendicitis is one of the most common diagnoses that general surgeons encounter in practice. An exceedingly rare cause of this disease is neoplasm. We report the case of a 24-year-old female who presented with non-specific right lower quadrant abdominal pain and equivocal findings of appendicitis and pelvic congestion syndrome on CT imaging. After an extensive work-up, the patient underwent a diagnostic laparoscopy with an appendectomy. The appendix appeared grossly normal; however, on a pathologic review of the specimen, a low-grade appendiceal mucinous neoplasm (LAMN) was found. This case is unique in that it demonstrates exclusive management of LAMN laparoscopically. It reinforces the need to approach non-specific abdominal pain from a multidisciplinary perspective and to utilize laparoscopy as a diagnostic/therapeutic modality when other, less invasive, modalities fail to diagnose a patient's pain.

Occult appendix pathology in patients undergoing colorectal cancer resection and prophylactic appendectomy

BACKGROUND

The risk-benefit balance of prophylactic appendectomy in patients undergoing left colorectal cancer resection is unclear. The aim of this report is to assess the proportion of histologically abnormal appendices in patients undergoing colorectal cancer resection in a unit where standard of care is appendectomy, with consent, when left-sided resection is performed.

METHODS

A retrospective study on a prospectively collected database was conducted in a single tertiary-care center. Overall, 717 consecutive patients undergoing colorectal cancer resection between January 2015 and June 2021 were analyzed. The primary outcome was the proportion of histologically abnormal appendix specimens at prophylactic appendectomy. The secondary outcome was complications from prophylactic appendectomy.

RESULTS

Overall, 576/717 (80%) patients had appendectomy at colorectal cancer surgery. In total, 234/576 (41%) had a right-/extended-right hemicolectomy or subtotal colectomy which incorporates appendectomy, and 342/576 (59%) had left-sided resection (left-hemicolectomy, anterior resection or abdominoperineal excision) with prophylactic appendectomy. At definitive histology, 534/576 (92.7%) had a normal appendix. The remaining 42/576 (7.3%) showed abnormal findings, including: 14/576 (2.4%) inflammatory appendix pathology, 2/576 (0.3%) endometriosis, 8/576 (1.4%) hyperplastic polyp, and 18/576 (3.1%) appendix tumors, which encompassed six low-grade appendiceal mucinous neoplasms (LAMNs), three carcinoids, and nine serrated polyps. In the 342 patients who had prophylactic appendectomy, 10 (2.9%) had a neoplasm (two LAMN, three carcinoids, and five serrated polyps). There were no complications attributable to appendectomy.

CONCLUSION

Occult appendix pathology in patients undergoing colorectal cancer resection is uncommon when prophylactic appendectomy was performed. However, approximately 3% of patients had a synchronous appendix neoplasm.

Long term survival outcomes of surgery combined with hyperthermic intraperitoneal chemotherapy for perforated low-grade appendiceal mucinous neoplasms: A multicenter retrospective study

BACKGROUND

Low-grade appendiceal mucinous neoplasms (LAMN) are very rare, accounting for approximately 0.2%-0.5% of gastrointestinal tumors. We conducted a multicenter retrospective study to explore the impact of different surgical procedures combined with HIPEC on the short-term outcomes and long-term survival of patients.

METHODS

We retrospectively analyzed the clinicopathological data of 91 LAMN perforation patients from 9 teaching hospitals over a 10-year period, and divided them into HIPEC group and non-HIPEC group based on whether or not underwent HIPEC.

RESULTS

Of the 91 patients with LAMN, 52 were in the HIPEC group and 39 in the non-HIPEC group. The Kaplan-Meier method predicted that 52 patients in the HIPEC group had 5- and 10-year overall survival rates of 82.7% and 76.9%, respectively, compared with predicted survival rates of 51.3% and 46.2% for the 39 patients in the non-HIPEC group, with a statistically significant difference between the two groups (χ2 = 10.622, p = 0.001; χ2 = 10.995, p = 0.001). Compared to the 5-year and 10-year relapse-free survival rates of 75.0% and 65.4% in the HIPEC group, respectively, the 5-year and 10-year relapse-free survival rates of 48.7% and 46.2% in the non-HIPEC group were significant different between the two outcomes (χ2 = 8.063, p = 0.005; χ2 = 6.775, p = 0.009). The incidence of postoperative electrolyte disturbances and hypoalbuminemia was significantly higher in the HIPEC group than in the non-HIPEC group (p = 0.023; p = 0.044).

CONCLUSIONS

This study shows that surgery combined with HIPEC can significantly improve 5-year and 10-year overall survival rates and relapse-free survival rates of LAMN perforation patients, without affecting their short-term clinical outcomes.

Which is the appropriate surgical procedure for appendiceal adenocarcinoma: appendectomy, partial colectomy or right hemicolectomy?

OBJECTIVE

The purpose of this study was to explore the appropriate surgical procedure and clinical decision for appendiceal adenocarcinoma.

METHODS

A total of 1,984 appendiceal adenocarcinoma patients from 2004 to 2015 were retrospectively identified from the Surveillance, Epidemiology, and End Results (SEER) database. All patients were divided into three groups based on the extent of surgical resection: appendectomy (N = 335), partial colectomy (N = 390) and right hemicolectomy (N = 1,259). The clinicopathological features and survival outcomes of three groups were compared, and independent prognostic factors were assessed.

RESULTS

The 5-year OS rates of patients who underwent appendectomy, partial colectomy and right hemicolectomy were 58.3%, 65.5% and 69.1%, respectively (right hemicolectomy vs appendectomy, P < 0.001; right hemicolectomy vs partial colectomy, P = 0.285; partial colectomy vs appendectomy, P = 0.045). The 5-year CSS rates of patients who underwent appendectomy, partial colectomy and right hemicolectomy were 73.2%, 77.0% and 78.7%, respectively (right hemicolectomy vs appendectomy, P = 0.046; right hemicolectomy vs partial colectomy, P = 0.545; partial colectomy vs appendectomy, P = 0.246). The subgroup analysis based on the pathological TNM stage indicated that there was no survival difference amongst three surgical procedures for stage I patients (5-year CSS rate: 90.8%, 93.9% and 98.1%, respectively). The prognosis of patients who underwent an appendectomy was poorer than that of those who underwent partial colectomy (5-year OS rate: 53.5% vs 67.1%, P = 0.005; 5-year CSS rate: 65.2% vs 78.7%, P = 0.003) or right hemicolectomy (5-year OS rate: 74.2% vs 53.23%, P < 0.001; 5-year CSS rate: 65.2% vs 82.5%, P < 0.001) for stage II disease. Right hemicolectomy did not show a survival advantage over partial colectomy for stage II (5-year CSS, P = 0.255) and stage III (5-year CSS, P = 0.846) appendiceal adenocarcinoma.

CONCLUSIONS

Right hemicolectomy may not always be necessary for appendiceal adenocarcinoma patients. An appendectomy could be sufficient for therapeutic effect of stage I patients, but limited for stage II patients. Right hemicolectomy was not superior to partial colectomy for advanced stage patients, suggesting omission of standard hemicolectomy might be feasible. However, adequate lymphadenectomy should be strongly recommended.

Cancer-specific survival in non-mucinous appendiceal adenocarcinomas after local resection versus right hemicolectomy: A Surveillance, Epidemiology, and End Results database study

BACKGROUND

Adenocarcinomas of the appendix are rare cancers for which no National Comprehensive Cancer Network guidelines exist, and for patients who undergo resection with curative intent, there is a paucity of data on prognostic factors affecting long-term cancer-specific survival. We aimed to compare the cancer-specific survival outcomes in adult patients with appendiceal non-mucinous adenocarcinoma undergoing either local resection versus right hemicolectomy.

METHODS

This was a retrospective study from the National Cancer Institute Surveillance, Epidemiology, and End Results of patients who underwent curative resection over a 15-year period (2004-2019) for primary appendiceal adenocarcinoma. Out of 16,699 patients, 14,945 were excluded (exclusion criteria were non-adenocarcinoma histological types and patients with regional or distant metastasis as per National Cancer Institute Surveillance, Epidemiology, and End Results stage). Effects of factors (age, race, tumor biology [mucinous versus non-mucinous tumors], the extent of resection of the primary lesion, and lymph nodes) on cancer-specific long-term survival were studied. Survival analysis was performed using the Kaplan-Meier method. Survival outcomes were reported as mean survival (months).

RESULTS

Of 1,754 patients, 827 (47.1%) were women, and 927 (52.1%) were men. The mean age in years (± standard deviation) was 62.43 ± 14.3. The racial distribution was as follows: Black 237 (13.5%), White 1,398 (79.7%), and Other 119 (6.8%). A total of 771 (44.6%) underwent local resection (appendectomy or segmental resection of colon without lymph node resection), and 983 (55.4%) underwent hemicolectomy with lymph node resection. Favorable survival prognosticators were age <50 years, White race, and well-differentiated histology. Patients with mucinous tumors experienced better survival. Patients who underwent right hemicolectomy with lymph node resection experienced better survival compared with those who had an appendectomy or segmental colonic resection for non-mucinous tumors rather than mucinous tumors.

CONCLUSION

We report novel demographic, tumor-related, and operative prognostic factors impacting long-term cancer-specific survival in patients who undergo resection for appendiceal adenocarcinoma. The extent of resection of the primary lesion with draining lymph nodes determines long-term cancer-specific survival in non-mucinous appendiceal adenocarcinomas.

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

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

Prolonged Survival in Peritoneal Metastatic Appendiceal Carcinoma Patients Treated With Combined Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

INTRODUCTION

Primary treatment for peritoneal dissemination of appendiceal cancer is the combination of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. The endpoints were overall survival and evaluation of prognostic factors.

METHODS

Clinicopathological and treatment-related factors were obtained from a prospective database. A total of 84 patients, 55 (65%) primary and 29 (35%) recurrent malignant appendiceal carcinomas with synchronous and metachronous peritoneal metastases, underwent multimodal treatment between 2011 and 2021. The endpoints of the study were overall survival and evaluation of prognostic factors.

RESULTS

The median follow-up was 4.8 y; the mean age was 54.5 y (range 25-77), with a sex distribution of 69% female and 31% male. The mean peritoneal cancer index was 11.3. The proportion of mucinous, intestinal-type, signet ring cell, and goblet cell carcinoma was 56%, 23%, 11%, and 10%, respectively. The 5-y survival rate of the whole cohort was 56.7%. In primary and recurrent diseases, the overall median survival was 8.4 and 4.9 y. Significantly improved survival was detected after complete cytoreduction resection (hazard ratio [HR] for CCR-2 versus CCR-0: 9.388, 95% confidence interval [CI] 3.026-29.124, P = 0.001) and initial local operation with undelayed admission to the center (HR 0.262, 95% CI 0.089-0.773; P = 0.015). The five independent factors in Kaplan-Meier analysis and univariable Cox regression analysis associated with significant adverse survival were cancer antigen (CA) 19-9 over 37 IU/mL, signet ring cell and intestinal-type histology, positive nodal status, grading, and peritoneal cancer index >20. Neoadjuvant chemotherapy administration did not impact survival (HR 1.220, 95% CI 0.612-2.432, P = 0.571).

CONCLUSIONS

With multimodal treatment, prolonged survival is attainable in stage IV primary and recurrent appendiceal carcinoma with peritoneal dissemination. Direct referral to specialized centers after confirmation of peritoneal metastasis is recommended because prompt definitive treatment may significantly improve survival.

The appendix "mucocoele" misnomer: radiological terminology of "likely appendix mucinous neoplasm" better reflects pathology findings

AIM

To review the radiological terminology used to describe dilated mucin-containing appendiceal lesions with correlation to the histopathological diagnosis.

MATERIALS AND METHODS

Radiology and histopathology reports for all patients with an abnormally dilated appendix referred to a tertiary peritoneal malignancy centre, between January 2021 and December 2021, were reviewed.

RESULTS

Overall, 213 patients were included with a median appendiceal diameter of 25.5 mm (range 10-125 mm). Peritoneal disease was present in 109 patients, with the remaining 104 cases demonstrating a dilated appendix only. Local radiology reports were available for 201 cases with the appendix described in 168 cases as appendiceal mucocoele (n=104), appendiceal neoplasm (n=40), appendicitis (n=18), and dilated appendix (n=6). The appendix was not mentioned in 33/201 (15%), either misinterpreted as other pathology (n=15) or not reported (n=18). Peritoneal malignancy histopathology reports were available in 188 cases and reported as low-grade appendix mucinous neoplasm (LAMN, n=144), high-grade appendix mucinous neoplasm (HAMN, n=13), LAMN with foci of HAMN (n=2), LAMN with neuroendocrine tumour (n=2), LAMN with goblet cell adenocarcinoma (n=1), goblet cell adenocarcinoma (n=8), mucinous adenocarcinoma (n=14), non-mucinous adenocarcinoma (n=1), and benign histology (n=3). Only one case of a true inflammatory "mucocoele"/retention cyst was reported.

CONCLUSION

In this cohort of patients, the overwhelming majority of dilated, mucin-filled appendices contained malignant cells and benign mucin-filled appendices were rare. The present authors advocate that the term "likely appendix mucinous neoplasm" should replace "appendix mucocoele" to represent the most likely pathology and facilitate less ambiguous interpretation in management decisions.

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

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

Retrospective Review of Outcomes in Non-Invasive Mucinous Appendiceal Neoplasms with and without Peritoneal Spread: A Cohort Study

Patients treated surgically for local non-invasive mucinous appendiceal neoplasm (NI-MAN) may recur with the development of peritoneal dissemination (PD). The risk of recurrence and predictive factors are not well studied. Patients with NI-MAN, with or without peritoneal dissemination at presentation, were included. Patients with limited disease underwent surgical resection only. Patients with peritoneal dissemination underwent cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC). Patients without PD (nPD) were compared to those who presented with PD. Thirty-nine patients were included, 25 in nPD and 14 in PD. LAMN was diagnosed in 96% and 93% of patients in nPD and PD, respectively. Acellular mucin on the peritoneal surface was seen in 16% of nPD patients vs. 50% of PD patients (p = 0.019). Two (8%) patients in the nPD group who had LAMN without wall rupture recurred, at 57 and 68 months, with a PCI of 9 and 22. The recurrence rate in the PD group was 36%. All recurred patients underwent CRS+HIPEC. A peritoneal recurrence is possible in NI-MANs confined to the appendix even with an intact wall at initial diagnosis. The peritoneal disease may occur with significant delay, which is longer than a conventional follow-up.

Comparison of the risk of appendiceal tumors in uncomplicated and complicated appendicitis

BACKGROUND

Interval appendectomy or non-operative management is commonly performed for complicated appendicitis in adult patients. However, these treatments are still controversial because the incidence rate of appendiceal tumors recognized after interval appendectomy is reportedly higher than that after emergency appendectomy. Thus, this study aimed to compare the appendiceal tumor rates between uncomplicated and complicated appendicitis.

METHODS

This study was a retrospective review of patients with appendicitis who underwent surgical removal at a single institution over 7.5 years. The primary objective was the comparison of the incidence rate of appendiceal tumors using propensity score matching, and the secondary objective was the same comparison among older patients, defined as patients aged ≥ 60 years.

RESULTS

A total of 1277 patients were included. Of these patients, 297 (23.3%) were preoperatively diagnosed with complicated appendicitis. Moreover, 22 (1.7%) patients, including 14 cases of complicated appendicitis and 8 cases of uncomplicated appendicitis, were diagnosed with appendiceal tumors based on pathological examination. No significant difference was found in the incidence rate of appendiceal tumors between the two groups after matching for patients' background, including age, sex, and history of appendicitis by propensity score matching (P = 0.073). However, among patients aged ≥ 60 years, the incidence of appendiceal tumors was significantly higher in complicated than in uncomplicated appendicitis (P = 0.006).

CONCLUSIONS

Although the overall risk of appendiceal tumors did not differ between complicated and uncomplicated appendicitis when analyzed by the propensity score matching, in older patients aged ≥ 60 years, the risk increased among those with complicated appendicitis. Therefore, although the incidence is low, complicated appendicitis, particularly, among older patients, should be examined carefully and be performed IA when unusual findings exist.

Appendiceal adenocarcinoma presenting as a bladder tumor

We present a case of an appendiceal adenocarcinoma that invaded the urinary bladder, which was preoperatively mistaken for urachal adenocarcinoma. The patient underwent open removal of the umbilicus, urachus, partial cystectomy and bilateral pelvic lymph node dissection. Intraoperatively the tumor was noted to involve the appendix, and so an appendectomy was also performed. The pathology showed an appendiceal adenocarcinoma invading the bladder wall. Urologists must have a high degree of suspicion for spread from a gastrointestinal primary when adenocarcinoma is found within the urinary bladder.

A low appendiceal mucinous neoplasm lesion in an inflamed appendix within an inguinal hernia

Amyand’s hernia, an incarcerated appendix inside an inguinal hernia, accounts for <1% of hernias in children and even less in adults. Similarly, low-grade appendiceal mucinous (LAMN) lesions are only found in <1% of removed appendices. We present the case of a 72-year-old man with a 15-year history of a large right inguinoscrotal hernia that presented with right lower quadrant pain, was found by computed tomography imaging to have an incarcerated appendix with a large fluid collection, and was post-operatively diagnosed with an LAMN lesion. Although our case is rare due to the simultaneity of the Amyand’s hernia and LAMN conditions, each separate condition is prevalent enough for most surgical providers to encounter at least one of these. For our case, we discuss the decisions made in the pre-operative and post-operative management and relevant literature.

A rare case of a Low Grade Appendiceal Mucinous Neoplasm in a 46-year-old Middle Eastern female - A case report

Introduction and importance

Mucinous cell neoplasia are rare and conceivably fatal causes of surgical abdomen. Adult manifestations can be obscure and ill-defined, yielding misdiagnoses and wasting precious time and effort to reach the correct one. Clinical awareness ought to be present once presented with a surgical abdomen in such a patient because this neoplasm may present with misleading presentations which mask the actual diagnosis and masquerade as a different one, and in turn, may result in performing a dissimilar treatment intervention. Rapid learnt surgical judgments must be taken and put into action to diminish the morbidity and mortality consequential to this pathology.

Case presentation

Our case is of a 46-year-old female, who was admitted into our hospital with a 2-month-history of general fatigue. Colicky abdominal pain and discomfort developed shortly prior to admission. Multi-Slice Computed Tomography (MSCT) scan exposed cystic formation in the terminal ileum. Exploratory laparotomy was warranted, in addition to performing a right hemicolectomy.

Clinical discussion

We treated our patient via open surgery and performing an appendectomy with right hemicolectomy in addition to the excision of several surrounding lymph nodes. Diagnosis is traditionally reached intraoperatively relying on gross morphology and postoperatively through histopathological analysis of the excised specimens.

Conclusion

Low Grade Appendiceal Mucinous Neoplasm is a scarce entity and varies critically in its manifestations, hence, it is existential to thoroughly study this kind of neoplasia, document it, and consider it, so that we can construct precise decisions to reach ideal results for patients who suffer from this neoplasm.

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Appendiceal primary tumors have an incidence rate of less than 2% of all excised samples of the appendix.

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Mucinous cell tumors of the appendix are ubiquitous in merely 0.2%–0.3% of all the excised samples of the appendix.

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Symptoms are ill-defined. This warrants high clinical suspicion when presented with a case of surgical abdomen.

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Surgery is the chief treatment method. Open surgery is favored over laparoscopic in appendiceal mucinous cell neoplasm.

Pseudomyxoma peritonei of appendiceal origin mimicking ovarian cancer - a case report with literature review

Pseudomyxoma peritonei (PMP) is a rare and uncommon condition, characterized by the presence of mucinous ascites in the abdominal cavity. The most common cause of PMP is mucinous adenocarcinoma of the appendix, followed by neoplasms of the ovary, endocervix, fallopian tube, alimentary organs, urachus, urinary bladder, lung, mucinous cyst of the spleen, and breast.

Herein, we report a case of a 64-year-old postmenopausal woman (gravida 2, para 2) who presented at the department of gynecology with a short history of nausea and abdominal distention. Abdominal and vaginal ultrasonography showed a large amount of free fluid in the pelvis with hyperechoic echogenicity and right pelvic tumor with mixed echogenicity. Computed tomography demonstrated the presence of a heterogeneous, hypodense mass, without contrast enhancement, located on the right side of the pelvis, near the right ovary. Laparotomy was performed. Revision of the abdominal cavity revealed a large amount of yellow gelatinous mucinous ascites – approximately 1.5 l. A tumor (6 x 7 cm in diameter), arising from the appendix and located in the pouch of Douglas near the right ovary, was observed. Histopathology examination revealed poorly differentiated mucinous appendiceal adenocarcinoma, comprising up to 50% signet ring cells.

Gastrointestinal tumors such as appendiceal neoplasms combined with PMP may mimic ovarian carcinomas. Computed tomography, abdominal/vaginal ultrasonography and tumor marker levels (carcino-embryonic antigen, carbohydrate antigen 19.9, carbohydrate antigen Ca-125) may establish the diagnosis.

A differential diagnosis with appendiceal tumors should be considered for patients with right pelvic masses.

A Case Report on Life-Threatening Lower Gastrointestinal Bleeding: A Rare Presentation of Mucinous Adenocarcinoma of the Appendix

Introduction

A life-threatening lower gastrointestinal bleeding from mucinous adenocarcinoma of the appendix is a rare occurrence. Diagnosing and management of such a condition are challenging. Case Presentation. A 73-year-old male with a history of type 2 diabetes mellitus and hypertension presented with intermittent per rectal bleeding for two weeks, which progressed to the passage of a large number of blood clots and fresh blood. He had features of class III shock on admission. An endoscopic evaluation followed initial resuscitation to locate the source of bleeding. Colonoscopy revealed a large blood clot at the opening of the appendicular orifice with no active bleeding. Oesophagoduodenoscopy, contrast-enhanced CT abdomen, and CT angiogram findings were unremarkable. Due to repeated episodes of rebleeding leading to haemodynamic instability, an exploratory laparotomy was performed. A retrocaecal appendix was noticed with a macroscopically suspicious-looking dilated tip adhered to the posterior caecal wall. Right hemicolectomy was performed as the lesion was suspicious and to stop bleeding from the site. Ileocolic side-to-side hand-sewn anastomosis was performed using 3/0 polyglactin. Postoperatively, per rectal bleeding was settled. Microscopy revealed appendiceal mucinous adenocarcinoma with AJCC staging of pT3NoMx. The patient was discharged on postoperative day seven and referred to oncological management. He was offered six cycles of chemotherapy with capecitabine and oxaliplatin. At the six-month follow-up visit, the patient had no features of recurrence clinically.

Conclusion

Mucinous adenocarcinoma of the appendix can rarely present as life-threatening lower GI bleeding. Prompt resuscitation, endoscopic evaluation, and operative management with right hemicolectomy and chemotherapy provided a good outcome.

Management of Low-Grade Appendiceal Mucinous Neoplasms (LAMN): An International Survey of Surgeons Performing CRS and HIPEC

BACKGROUND

Low-grade appendiceal mucinous neoplasms (LAMN) are commonly managed by community surgeons at diagnosis. There is variability in the treatment of LAMN, both by community and specialist providers. We assessed current management practices for LAMN across surgeons with expertise in peritoneal surface malignancies (PSM).

METHODS

An online survey was sent to 106 international surgeons specializing in PSM. The survey assessed demographics, favored pre-referral management, and definitive management practices for LAMN.

RESULTS

The response rate was 40% (67% USA, 33% international). Respondents had performed a median of 18 (interquartile range [IQR] 7.75-29) HIPEC cases in the last year, of which 10 (IQR 4-20) were for LAMN. Ninety-three percent reported more than half of LAMN referrals had already undergone surgery-an estimated 50% appendectomy and 20% right hemicolectomy (RH). No surgeon respondents supported performing right hemicolectomy before referral. For LAMN confined to the appendix, 86% of respondents would definitively treat with appendectomy. In the presence of mucinous implants, 24% would observe after appendectomy and 76% would proceed with HIPEC. All would perform HIPEC if implants contained tumor cells. When LAMN involved the appendiceal base, 67% of respondents would proceed with partial cecectomy, while 33% favored RH.

CONCLUSIONS

Pre-referral management of LAMN is not standardized and 20% of patients were referred to a surgeon who performs CRS/HIPEC after a right hemicolectomy that would not have been recommended. Management of LAMN by surgeons who treat PSM is also variable. Long-term data and identification of prognostic features are necessary to generate consensus on the optimal management of these complex patients.

Primary Appendiceal Adenocarcinoma Presenting with Hematochezia due to the Invading Tumor in the Sigmoid Colon

Primary appendiceal tumors are rare malignancies; some cases have been described to invade other organs, and this represents a very rare clinical condition. We report a case of appendiceal adenocarcinoma invading the sigmoid colon and a review of similar cases. A 69-year-old woman with complaints of hematochezia was admitted to the hospital. Colonoscopy revealed a tumor in the sigmoid colon, which was a well-differentiated tubular adenocarcinoma. A computed tomography scan showed an appendiceal mass that involved the sigmoid colon, suggesting an appendiceal cancer invading the sigmoid colon. Ileocecal resection with extended lymphadenectomy and en bloc resection of the sigmoid colon was performed. The appendiceal tumor involved the sigmoid colon and the terminal ileum. The ileocecal part which included the tumor and the involved sigmoid colon was resected in total. Macroscopic findings showed that the appendiceal tumor made a fistula with the sigmoid colon. Pathological examination revealed that the tumor was a well-differentiated tubular adenocarcinoma that invaded the sigmoid colon. The final pathological stage was T4bN0M0, stage IIC. The patient was discharged from the hospital uneventfully. She was alive without relapse after a 20-month follow-up. Although an appendiceal tumor invading the rectosigmoid region is rare, a preoperative diagnosis can be obtained that facilitates the planning of a suitable surgical procedure: en bloc resection of the ileocecal part and the rectosigmoid part.

Mode of Presentation in 1070 Patients With Perforated Epithelial Appendiceal Tumors, Predominantly with Pseudomyxoma Peritonei

BACKGROUND

Perforated epithelial appendiceal tumors are uncommon and can give rise to pseudomyxoma peritonei. Pseudomyxoma peritonei is rare, almost always of appendiceal origin, and presents in various ways relevant to abdominal surgeons.

OBJECTIVE

The aim of this study was to report the mode of presentation of pseudomyxoma peritonei of appendiceal origin in patients treated in a high-volume UK peritoneal malignancy center.

DESIGN

A retrospective observational study was conducted.

SETTINGS

This was a single-center study.

PATIENTS

Retrospective analysis of a prospective database of consecutive patients undergoing surgery between March 1994 and December 2016 was performed.

MAIN OUTCOME MEASURES

Mode of presentation was classified into 7 categories: "histological diagnosis at abdominal surgery for presumed appendicitis," "probable pseudomyxoma peritonei" based on abnormality on cross-sectional imaging (± image-guided biopsy)," "abnormal imaging (other cause suspected) and operative finding of pseudomyxoma peritonei," "diagnostic laparoscopy," "ovarian mass," "new-onset hernia," and "miscellaneous."

RESULTS

Overall, 1070 patients underwent surgery (female 61%, male 39%); median age was 57. The mode of presentation was abnormality on cross-sectional imaging in 324 of 1070 patients (30.3%), histological diagnosis at emergency surgery for presumed appendicitis in 203 of 1070 patients (19%), and abnormal imaging with eventual pseudomyxoma peritonei diagnosis in 180 of 1070 patients (16.8%); 124 of 651 women (19.2%) presented with an ovarian mass. New-onset hernia was the presenting feature in 9.9%; 83 of 1070 patients (7.7%) were diagnosed at diagnostic laparoscopy, and 32 of 1070 patients (3%) were described as "miscellaneous." Overall, 775 of 1070 patients (72.4%) had complete cytoreductive surgery with 10-year survival of 63.5%.

LIMITATIONS

Results are limited by the retrospective nature of the study, radiological improvements over the study period, and the number of patients who had overlapping features at presentation.

CONCLUSION

Perforated appendiceal tumors present in various ways but predominantly at cross-sectional imaging or coincidentally at laparoscopy or laparotomy. All abdominal surgeons will occasionally encounter cases, often unexpectedly, and recognition and referral to a specialized unit results in excellent outcomes in most cases. See Video Abstract at http://links.lww.com/DCR/B256. MODO DE PRESENTACIÓN EN 1070 PACIENTES CON TUMORES EPITELIALES APENDICULARES PERFORADOS, PREDOMINANTEMENTE CON PSEUDOMIXOMA PERITONEAL: Los tumores epiteliales apendiculares perforados son poco frecuentes y pueden dar lugar a Pseudomyxoma peritonei. El pseudomixoma peritoneal es raro, casi siempre de origen apendicular, y se presenta de diversas formas relevantes para los cirujanos abdominales.El objetivo fue informar el modo de presentación del Pseudomixoma peritoneal de origen apendicular en pacientes tratados en un centro de malignidad peritoneal de alto volumen en el Reino Unido.Se realizó un estudio observacional retrospectivo.Este fue un estudio de centro único.Análisis retrospectivo de una base de datos prospectiva de pacientes consecutivos sometidos a cirugía entre marzo de 1994 y diciembre de 2016.El modo de presentación se clasificó en 7 categorías: "diagnóstico histológico en la cirugía abdominal por presunta apendicitis", "probable Pseudomixoma peritoneal" basado en la anormalidad en la imagen de corte transversal (biopsia guiada por imagen +/-), "imagen anormal (se sospecha otra causa) y hallazgo quirúrgico de Pseudomixoma peritoneal", "laparoscopia diagnostica", "masa ovarica", "hernia de reciente aparicion" y "varios".En total, 1070 pacientes fueron operados (mujeres 61%, hombres 39%); edad media 57. El modo de presentación fue anormalidad en la imágen transversal en 324/1070 (30.3%), el diagnóstico histológico en cirugía de emergencia por presunta apendicitis en 203/1070 (19%), la imágen anormal con eventual diagnóstico de Pseudomixoma peritoneal en 180 / 1070 (16.8%), 124/651 (19.2%) las mujeres presentaron una masa ovárica. La hernia de reciente aparición fue la característica de presentación en 9.9%, 83/1070 (7.7%) fueron diagnosticados por laparoscopia diagnóstica y 32/1070 (3%) "misceláneos". En general, 775/1070 (72,4%) se sometió a cirugía citorreductora completa con una supervivencia a 10 años del 63,5%.Una deficiencia es que los resultados están limitados por la naturaleza retrospectiva del estudio, las mejoras radiológicas a lo largo del período de estudio, y varios pacientes tenían características superpuestas en la presentación.Los tumores apendiculares perforados se presentan de varias maneras, pero predominantemente en imágenes transversales o casualmente en laparoscopia o laparotomía. Todos los cirujanos abdominales encontrarán ocasionalmente con casos, a menudo inesperados, y el reconocimiento y la derivación a una unidad especializada da lugar a excelentes resultados en la mayoría de los casos. Consulte Video Resumen en http://links.lww.com/DCR/B256.).

Preoperative computed tomography is poor in detecting tumors of the appendix among patients with acute appendicitis: A cohort study of 5,224 appendectomies

BACKGROUND

Neoplastic processes are among the known etiologies for acute appendicitis. While conservative treatment with antibiotics alone has been proposed as a treatment for uncomplicated appendicitis, the presence of tumors should be excluded when offering patients this option. The aim of this study was to assess the accuracy of computed tomography (CT) in detecting appendiceal tumors.

METHOD

Consecutive patients operated on for acute appendicitis between January 2007 and October 3, 2018, in our university hospital were included. Whenever appendiceal tumor was histopathologically confirmed, CT interpretations and surgical reports were carefully reviewed. All CT scans were reanalyzed by consultant body radiologists. Discrepancies between the preliminary and final radiological interpretations were noted.

RESULTS

A total of 5,224 patients underwent appendectomy, of whom 4,766 had histopathologically confirmed acute appendicitis. Eighty-four patients (median, 61 (13-89) years; 54% female) were diagnosed with appendiceal tumor. Fifty-two patients (62%) had uncomplicated appendicitis. Although incidence of tumors was associated with older age, tumors were found in all ages. The share of tumors increased from 1.7% to 3.0%/year during the study. The most common tumors were neuroendocrine tumors (n = 33), low-grade appendiceal mucinous neoplasms (n = 14), and adenocarcinomas (n = 11). Sixty-one patients (73%) underwent preoperative CT. Computed tomography interpretation during on-call hours suspected tumor in only one case (3.4%) with invasive tumor, and in five cases (16%) with noninvasive tumor.

CONCLUSION

Appendiceal tumors are possible findings in appendix specimens, and most patients had uncomplicated acute appendicitis. In light of findings we conclude that CT cannot be used to exclude neoplastic etiology underlying acute appendicitis.

LEVEL OF EVIDENCE

Diagnostic, level IV.

Preoperative Factors Associated with Appendiceal Tumors in Nonelective Appendectomy

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

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

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

Analysis of Clinical Characteristics of Low-Grade Appendiceal Mucinous Neoplasm (LAMN): A Retrospective Cohort Study of 51 LAMN Patients

INTRODUCTION

Low-grade appendiceal mucinous neoplasm (LAMN) is a rare disorder. There is no consensus on the prognosis and management of LAMN.

MATERIALS AND METHODS

We reviewed 51 consecutive patients with LAMN from 2013 to 2018. We divided our patients into two groups. The first is patients with an intact appendix. The second group comprises patients with the potential to develop a malignant condition. Comparisons of serum tumor markers between two groups were performed. Survival curves were estimated. Univariate and multivariate Cox proportional hazards were computed for 46 patients with median follow-up of 2.7 years.

RESULTS

Comparison of patients in two groups revealed significant differences in the mean level and abnormal ratio of CA125 (p < 0.001, p < 0.001), CA19-9 (p = 0.04, p = 0.04), and CEA (p = 0.001, p = 0.02). Eight patients had relapsed by the last follow-up in the second group. Patients with normal CEA had significantly longer disease-free survival (DFS) time than those with abnormal CEA (p = 0.04). CA19-9 exhibited a significant association with DFS (HR = 5.72, p = 0.02) in the Univariate Cox proportional hazards.

DISCUSSION

The prognosis of LAMN is related to serum tumor markers, the surgical procedure and the pathology.

Appendicular neoplasms and consequences in patients undergoing surgery for suspected acute appendicitis

INTRODUCTION

In patients treated with an appendectomy for acute appendicitis, the specimen is generally sent for histological evaluation. In an era of increasing non-operative treatment for acute appendicitis, it is important to know the incidence, the diagnostic accuracy, and treatment consequences of appendicular neoplasms that are found in acute appendicitis. We hypothesize that pre- and intra-operative parameters might predict an appendicular neoplasm.

METHODS

Data was used from our previous prospective observational cohort study. All patients undergoing surgery for suspected acute appendicitis were included. The primary outcome was the incidence of appendicular neoplasms in patients operated for acute appendicitis. Secondary outcomes were pre-operative diagnostics and imaging outcomes, intra-operative surgical judgment, and postoperative management and outcome. Possible predictors of an appendicular neoplasm were identified and used in multivariable logistic regression. Patients with an appendicular neoplasm were followed for 3 years after initial appendectomy.

RESULTS

A total of 1975 patients underwent surgery for suspected acute appendicitis and in 98.3% (1941/1975) the appendix was removed. In 1.5% (30/1941) of these patients, an appendicular neoplasm was found. Among the malignant neoplasms, the majority were grade 1 neuroendocrine tumors (NET) in 65% (13/20). On pre-operative imaging, there was no suspicion of malignancy. In three cases, there was an intra-operative suspicion of malignancy. Multivariable analysis showed only age as an independent predictor for appendicular neoplasms. No recurrent or new malignancy was found during follow-up.

DISCUSSION

The incidence of appendicular neoplasm in patients undergoing an acute appendectomy is very low and clinical risk factors could not be identified.

Communication and management of incidental pathology in 1,214 consecutive appendicectomies; a cohort study

BACKGROUND

Important incidental pathology requiring further action is commonly found during appendicectomy, macro- and microscopically. We aimed to determine whether the acute surgical unit (ASU) model improved the management and disclosure of these findings.

METHODS

An ASU model was introduced at our institution on 01/08/2012. In this retrospective cohort study, all patients undergoing appendicectomy 2.5 years before (Traditional group) or after (ASU group) this date were compared. The primary outcomes were rates of appropriate management of the incidental findings, and communication of the findings to the patient and to their general practitioner (GP).

RESULTS

1,214 patients underwent emergency appendicectomy; 465 in the Traditional group and 749 in the ASU group. 80 (6.6%) patients (25 and 55 in each respective period) had important incidental findings. There were 24 patients with benign polyps, 15 with neuro-endocrine tumour, 11 with endometriosis, 8 with pelvic inflammatory disease, 8 Enterobius vermicularis infection, 7 with low grade mucinous cystadenoma, 3 with inflammatory bowel disease, 2 with diverticulitis, 2 with tubo-ovarian mass, 1 with secondary appendiceal malignancy and none with primary appendiceal adenocarcinoma. One patient had dual pathologies. There was no difference between the Traditional and ASU group with regards to communication of the findings to the patient (p = 0.44) and their GP (p = 0.27), and there was no difference in the rates of appropriate management (p = 0.21).

CONCLUSION

The introduction of an ASU model did not change rates of surgeon-to-patient and surgeon-to-GP communication nor affect rates of appropriate management of important incidental pathology during appendectomy.

Predictors for interval appendectomy in non-operatively treated complicated appendicitis

PURPOSE

To determine the incidence rate and identify predictive factors for interval appendectomy after non-operatively treated complicated appendicitis.

METHODS

Single-center retrospective cohort study conducted between January 2008 and June 2017. Adult patients with acute appendicitis were identified. Patients with complicated appendicitis initially treated non-operatively were included. Outcomes included abscess rate on imaging, results of additional imaging during follow-up, incidence rate of and surgical indications for interval appendectomy, and outcomes of histological reports.

RESULTS

Of all adult patients with acute appendicitis (n = 1839), 9% (170/1839) was initially treated non-operatively. Median age of these patients was 55 years (IQR 42-65) and 48.8% (83/170) were men. In 36.4% (62/170) of the patients, an appendicular abscess was diagnosed. 62.4% (106/170) did not require subsequent surgery (no interval appendectomy group) and in 37.6% (64/170), an interval appendectomy was performed (interval appendectomy group). Median follow-up was 80 weeks (17-192) and 113 weeks (34-246), respectively. Most frequent reason to perform subsequent surgery was recurrent appendicitis (45% (29/64)). Increasing age was significantly associated with a lower risk of undergoing interval appendectomy (OR 0.7; CI 0.6-0.89); p = 0.002). In the interval appendectomy group, appendicular neoplasm was found in 11% (7/64) of the patients, in contrast to 1.5% (25/1669) of the patients that had acute surgery (p < 0.001).

CONCLUSIONS

One out of three patients non-operatively treated for complicated appendicitis required an interval appendectomy. The incidence of appendicular neoplasms was high in these patients compared with those that had acute surgery. Therefore, additional radiological imaging following non-operatively treated complicated appendicitis is recommended.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Primary adenocarcinoma of the appendix in a child: A case report

BACKGROUND

Primary adenocarcinoma of the appendix is a rare disease in clinical practice. Moreover, primary adenocarcinoma of the appendix in the pediatric age group is even rarer with very little cases being published. Here, we report a case of primary adenocarcinoma of the appendix with local invasion into adjacent organs in a child who was initially diagnosed as having an acute appendicitis.

CASE PRESENTATION

A 13-year-old girl presented with abdominal pain of 3-month duration. Imaging study showed a mass including the fecalith that occupied her pelvic and right lower abdominal cavity. Drainage of the abscess and appendectomy were performed by the preoperative diagnosis of an acute appendicitis with an appendiceal mass. Postoperative histopathological examinations revealed the appendiceal adenocarcinoma. She then received the whole mass resection, ileocecal resection with lymph node dissection. The masses were tightly adherent with infiltration into the sigmoid colon, uterus, and right ovary. These organs were all dissected, and subsequent sigmoid colostomy was performed. We preserved the left ovary for her fertility. The pathological findings demonstrated negative margins and no lymph node invasions, and final pathological stage was pT4(SI)N0M0, stage II. After the operation, she received the chemotherapy with 6 cycles of 5-fluorouracil (5-FU), leucovorin (LV), and oxaliplatin (mFOLFOX6) and subsequent 6 cycles of simplified LV and 5-FU (sLV5FU2). The patient is doing well till today on follow-up without progression of the disease 5 years after the operation.

CONCLUSION

Primary adenocarcinoma of the appendix is exceedingly rare in children. In this report, we described one of the youngest primary adenocarcinomas of an appendix case ever reported. When encountering atypical cases of the appendicitis, we should consider the possibility of primary adenocarcinoma of the appendix as it has an extremely poor prognosis and is usually diagnosed in advanced stages.

Pseudomyxoma peritonei: natural history and treatment

Pseudomyxoma peritonei (PMP) is an uncommon disease characterised by mucinous ascites, classically originating from a ruptured low grade mucinous neoplasm of the appendix. The natural history of PMP revolves around the "redistribution phenomenon", whereby mucinous tumour cells accumulate at specific sites with relative sparing of the motile small bowel and to a lesser extent other parts of the gastrointestinal tract. Peritoneal tumour accumulates due to gravity and at the sites of peritoneal fluid absorption, namely, the greater and lesser omentum and the under-surface of the diaphragm, particularly on the right. The optimal treatment is complete macroscopic tumour excision termed cytoreductive surgery (CRS) combined with Hyperthermic Intra-Peritoneal Chemotherapy (HIPEC). Total operating time for complete CRS and HIPEC for extensive PMP is around 10 h and generally involves bilateral parietal and diaphragmatic peritonectomies, right hemicolectomy, radical greater omentectomy with splenectomy, cholecystectomy and liver capsulectomy, a pelvic peritonectomy with, or without, rectosigmoid resection and bilateral salpingo-oophorectomy with hysterectomy in females. A unique feature of low grade PMP, which differs from other peritoneal malignancies, includes slow disease progression, which may be asymptomatic until advanced stages. Additionally, very extensive disease with a high "PCI" (Peritoneal Carcinomatosis Index) may still be amenable to complete excision and cure. In cases where complete tumour removal is not feasible, maximum tumour debulking can still result in long-term survival in PMP. PMP is challenging, complex but nevertheless the most rewarding peritoneal malignancy amenable to cure by CRS and HIPEC.

Peritoneal Involvement Is More Common Than Nodal Involvement in Patients With High-Grade Appendix Tumors Who Are Undergoing Prophylactic Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Right hemicolectomy is routinely recommended in patients with histologic findings of high-grade appendix tumors after appendicectomy. Undetected peritoneal disease may be encountered at surgery. In high-grade appendix tumors with disease detected radiologically, complete cytoreduction may not be possible and outcomes poor. For these reasons, we adopted a policy of prophylactic cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

OBJECTIVE

The purpose of this study was to quantify the rates of peritoneal and nodal metastatic disease in patients with high-grade appendix tumors without obvious metastatic disease and to report the long-term outcomes of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in these patients.

DESIGN

Data regarding peritoneal and nodal metastatic disease were extracted from surgical and histologic records.

SETTINGS

The study was conducted at a high-volume tertiary referral center for peritoneal malignancy.

PATIENTS

Patients referred with histologically high-grade appendix tumors at appendicectomy, without detectable metastatic spread, between January 1994 and September 2016 were included MAIN OUTCOME MEASURES:: A total of 62 patients with high-grade pathology at appendicectomy, without clinical or radiological peritoneal disease, underwent complete cytoreduction with hyperthermic intraperitoneal chemotherapy.

RESULTS

Thirty-five (57%) of 62 patients had peritoneal disease (median peritoneal cancer index 5 (range, 1-28)). Eleven (31%) of 35 had microscopic peritoneal disease. Overall, 23 (37%) of 62 had peritoneal disease beyond the confines of a standard right hemicolectomy. Nine (15%) of 62 had nodal involvement. Mean overall and disease-free survival were 110.9 (95% CI, 94.8-127.0 mo) and 102.1 months (95% CI, 84.3-119.9 mo), with 5-year overall and disease-free survival of 83.2% and 76.0%.

LIMITATIONS

The retrospective nature limits the interpretation of these results.

CONCLUSIONS

Complete cytoreduction was achieved in all of the patients, with excellent long-term survival. The incidence of peritoneal spread (57%) compared with nodal involvement (15%) supports cytoreductive surgery and hyperthermic intraperitoneal chemotherapy as definitive treatment rather than prophylaxis in patients with high-grade appendix tumors, even without radiologically detectable disease. High-grade appendix tumors benefit from early aggressive operative management to deal with potential peritoneal and nodal spread and should be considered for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. See Video Abstract at http://links.lww.com/DCR/A360.

An Uncommon Cause of Small Bowel Bleeding from Appendiceal Carcinoma

Massive hematochezia caused by a small bowel lesion is a rare entity. Currently, video capsule endoscopy and balloon-assisted enteroscopy are effective in identifying the source of small intestine bleeding. Herein, we report a case of small bowel bleeding caused by a nonmucinous appendiceal adenocarcinoma with ileal invasion which was detected by video capsule endoscopy and single-balloon endoscopy. Despite the advanced disease stage with hepatic and peritoneal metastases, as of September 2016 the patient has had 8 years' disease-free survival after surgical resection and chemotherapy.

Appendix adenocarcinoma in an elderly patient from a nursing home

Appendiceal malignancies are rare clinic entities. The clinical presentation of appendiceal malignancies is often atypical. Acute abdominal pain and acute appendicitis, which requires early surgical intervention, are the most common clinical presentations of appendiceal malignancies. In this case report, an adenocarcinoma of the appendix in a 64-year-old male from a nursing home has been presented. He had right lower quadrant pain for the last 5 days. On physical examination, he had significant guarding. Intravenous contrast-enhanced abdominopelvic tomography revealed no pathological features. Laparotomy under general anesthesia was scheduled. During exploration, a perforated appendicitis was observed. Formal appendectomy was performed. The patient was lost due to pneumonia and septic shock 5 days after surgical intervention. In addition, the natural history of the disease and its basic diagnostic and therapeutic aspects are discussed. Preoperative or intraoperative diagnosis may not be available for some patients. Thus, routine histopathological examination is essential for adequate diagnosis and treatment.

Pathology of Mucinous Appendiceal Tumors and Pseudomyxoma Peritonei

Neoplasms of the appendix are rare, but because of their unusual presentation and unpredictable biologic behavior, it is important to diagnose them correctly. Mucinous tumors account for 58 % of malignant tumors of appendix in SEER database and the remaining are carcinoids. The mucinous appendiceal tumors have a potential to spread to the peritoneum and viscera in the form of gelatinous material with or without neoplastic cells resulting in Pseudomyxoma peritonei. (PMP) PMP is a clinical entity that has a unique biological behavior and can arise from seemingly benign tumors to frankly malignant ones. Several classifications exist for PMP of which Ronnet's classification has been the most popular. In 2010, the WHO proposed a 2 tier classification that classified PMP as either low grade or high grade based on the presence of mucin, cytological and architectural features. According to this classification when the underlying cause for PMP is an appendiceal tumor it is always a mucinous adenocarcinoma rather than a mucocoele or adenoma and these terms should no longer be used. This system of classification helps in predicting the behavior of the tumor and proper treatment strategies. The understanding of the pathogenesis of the disease has also improved with identification of newer biomarkers and molecular genetic alterations. IHC markers CK 20, CDX2 and MUC2 are found to be positive in these tumors in addition to KRAS mutation and loss of heterozygosity in some gene loci. Proper histopathologic classification and predicting the tumor behavior requires a close interaction between the pathologist and the surgeon. The use of the combined modality treatment of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has led to a 5-year survival ranging from 62.5 % to 100 % for low grade, and 0 %-65 % for high grade disease. This article focuses on the etiopathogenesis, clinical behavior, diagnosis and classification of mucinous tumors of the appendix and pseudomyxoma peritonei.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1000 patients with perforated appendiceal epithelial tumours

PURPOSE

To report early and long term outcomes following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in 1000 patients with perforated appendiceal epithelial tumours, predominantly with pseudomyxoma peritonei (PMP).

METHODS

Retrospective analysis of a prospective database of 1000 consecutive patients undergoing CRS and HIPEC for perforated appendiceal tumours between 1994 and 2014 in a UK National Peritoneal Malignancy unit.

RESULTS

Overall 1000/1444 (69.2%) patients treated for peritoneal malignancy had appendiceal primary tumours. Of these 738/1000 (73.8%) underwent complete cytoreductive surgery (CCRS), 242 (24.2%) had maximal tumour debulking (MTD) and 20 (2%) had laparotomy and biopsies only. Treatment related 30-day mortality was 0.8% in CCRS and 1.7% in MTD group with major postoperative morbidity rates of 15.2% (CCRS) and 14.5% (MTD). Five- and 10-year overall survival was 87.4% and 70.3% in the 738 patients who had CCRS compared with 39.2% and 8.1% respectively in the MTD group. On multivariate analysis, significant predictors of reduced overall survival were male gender (p = 0.022), elevated CEA (p = 0.001), elevated CA125 (p = 0.001) and high tumour grade or adenocarcinoma (p = 0.001).

CONCLUSIONS

Perforated epithelial appendiceal tumours are rare, though may be increasing in incidence and can present unexpectedly at elective or emergency abdominal surgery, often with PMP. CRS and HIPEC results in good long term outcomes in most patients.

Pathophysiology and classification of pseudomyxoma peritonei

Background: The term pseudomyxoma peritonei (PMP) was first described in 1884 and there has been much debate since then over the term. A recent consensus of world experts agreed that PMP should be thought of as a clinical entity characterised by the presence of mucinous ascites, omental cake, peritoneal implants and possibly ovarian involvement. It generally originates from mucinous appendiceal tumours. Content: This review details the clinical presentation of this unusual condition, presents the new classification system and how this relates to outcome. The pathophysiology of this disease is also explored with a special reference to the relationship of the disease to tumour markers. Summary: A classification system has been agreed upon by the leading experts in PMP which is now divided into low and high grade mucinous carcinomatosis peritonei. This distinction correlates with clinical outcome as does the presence of raised tumour markers preoperatively. Outlook: Research needs to be focused on understanding the factors associated with poor prognosis through well designed multi-centred prospective studies. This will allow us to identify patients with bad tumour biology so that targeted treatment based on likely prognosis may then become a reality.

Beyond appendicitis; radiologic review of unusual and rare pathology of the appendix

Appendicitis is a very common cause of acute abdominal pathology, however, many other pathologic conditions of the appendix can be diagnosed utilizing CT. Examples of these conditions include primary appendiceal neoplasms, secondary inflammation of the appendix, stump appendicitis, endometriosis, appendicitis within a hernia, appendiceal diverticulosis and intussusception and intraluminal foreign bodies. The purpose of this article is to review appendiceal pathology outside of acute appendicitis, describe corresponding imaging findings on CT, and to illustrate various CT findings of appendiceal disease with representative cases.

Appendiceal Goblet Cell Carcinoids: Management Considerations from a Reference Peritoneal Tumour Service Centre and ENETS Centre of Excellence

BACKGROUND

Appendix goblet cell carcinoids are known to share histological features of adenocarcinoma and neuroendocrine tumours. Due to their low incidence, quality evidence is lacking for the management of these patients.

METHODS

We performed a single-centre retrospective study of patients with a confirmed diagnosis of appendiceal goblet cell carcinoid (GCC; 1996-2014). Patients were divided into curative intent (CI) and palliative intent (PI) cohorts. Our primary end point was overall survival (OS).

RESULTS

Seventy-four patients were eligible; 76% were treated with CI [surgery only (36%), cytoreductive surgery (CRS) and hyperthermic intra-peritoneal chemotherapy (HIPEC; 36%), adjuvant chemotherapy (20%) and a combination of CRS and HIPEC followed by adjuvant chemotherapy (9%)], and 23% had advanced-stage disease amenable to palliative treatment (chemotherapy or supportive care) only. Completion right hemicolectomy, performed in 64% of the CI cohort, did not impact on the relapse rate or disease-free survival. FOLFOX chemotherapy was used in both the adjuvant and palliative settings; safety was as expected, and we observed a high rate (60%) of disease control in the palliative cohort. The estimated median OS (all patients), disease-free survival (CI patients) and progression-free survival (PI patients) were 52.1 (95% CI 29.4-90.3), 75.9 (26.6-not reached) and 5.3 (0.6-5.7) months, respectively. Age and stage were independent factors associated with OS in the multivariable analysis. Tang classification showed a trend for impact on OS. No benefit from specific adjuvant approach was identified; however, selection bias for treatment approach was observed.

CONCLUSION

Prospective trials are needed to define optimal approaches in GCC. All GCC patients should be managed by specialized centres due to their esoteric behaviour; we provide management considerations based on our experience and conclusions.

Appendiceal mixed adenoneuroendocrine carcinomas, a rare entity that can present as a Krukenberg tumor: case report and review of the literature

BACKGROUND

Mixed adenoneuroendocrine carcinoma is a rare tumor recently recognized as a new category in the last World Health Organization (WHO) classification of appendiceal tumors (2010). This term has been proposed to designate carcinomas of the appendix that arise by progression from a pre-existing goblet cell carcinoid. Mixed adenoneuroendocrine carcinomas are more aggressive tumors than typical goblet cell carcinoids and usually present with peritoneal spreading and ovarian masses. Staging, some histological features, and completeness of surgery are factors that determine its evolution.

CASE PRESENTATION

We report the case of a mixed adenoneuroendocrine carcinoma--signet ring cell subtype--that presented as a Krukenberg tumor of unknown primary.

CONCLUSION

The review of literature is focused on the most recent WHO pathologic classification of appendiceal tumors containing goblet cell clusters, which seems to correlate with prognosis. A management proposal for mixed adenoneuroendocrine carcinomas reported in previous literature is also discussed. This ranges from right hemicolectomy to cytoreduction plus hyperthermic intraperitoneal chemotherapy, in both cases usually followed by intravenous chemotherapy.

Clinicopathologic and Prognostic Features in Patients with Peritoneal Metastasis from Mucinous Adenocarcinoma, Adenocarcinoma with Signet Ring Cells, and Adenocarcinoid of the Appendix Treated with Cytoreductive Surgery and Perioperative Intraperitoneal Chemotherapy

BACKGROUND

Tumors that show a signet ring or adenocarcinoid histomorphology have been associated with a poor prognosis. This study aimed to analyze the clinicopathologic and prognostic features in patients with peritoneal metastasis from mucinous adenocarcinoma (PMCA), adenocarcinoma with signet ring cell (PMCA-S), or adenocarcinoid (PMCA-A) of the appendix treated with cytoreductive surgery and perioperative intraperitoneal chemotherapy.

METHODS

Retrospective analysis of a prospectively maintained database for all patients treated for appendiceal adenocarcinoma from 1989 to 2012 was performed.

RESULTS

The study cohort consisted of 494 patients including 361 patients with PMCA (73.1 %), 80 patients with PMCA-S (16.2 %), and 53 patients with PMCA-A (10.7 %). The patients comprised 273 men (55.3 %) and 221 women (44.7 %) with a mean age at presentation of 50.7 years for the PMCA-S patients, 47.3 years for the PMCA patients, and 47.5 years for the PMCA-A patients (p < 0.03). The 3- and 5-year survival rates were respectively 51 and 38 % for PMCA compared with 30 and 22 % for PMCA-S and 26 and 15 % for PMCA-A. The median survival time was 45.4 months for PMCA compared with 18.9 months for PMCA-S and 26.8 months for PMCA-A (p < 0.000). The groups did not differ significantly in the completeness of cytoreduction achieved, with 53.5 % of the PMCA patients having a CC0/1 compared with 46.2 % of the PMCA-S patients and 41.6 % of the PMCA-A patients (p < 0.20). In the multivariate analysis, the independent predictors of a reduced survival were incompleteness of cytoreduction, histomorphology of PMCA-S or PMCA-A, and distant metastasis.

CONCLUSION

The findings showed that PMCA-S or PMCA-A histomorphology contributes to the poor prognosis associated with peritoneal metastasis from appendiceal adenocarcinoma. The independent predictors for a poor overall survival included incompleteness of cytoreduction, PMCA-S and PMCA-A histomorphology, and distant metastasis.