Clinical presentation of pseudomyxoma peritonei

Optimal peritoneal cancer index cutoff point for predicting surgical resectability of pseudomyxoma peritonei in treatment-naive patients

BACKGROUND

The peritoneal cancer index (PCI) has been used to predict surgical outcomes for pseudomyxoma peritonei (PMP). The present study aimed to establish the optimal cutoff point for PCI to predict surgical resectability of PMP.

METHODS

A total of 366 PMP patients were included. The patients were divided into low-grade and high-grade groups. Based on the completeness of the cytoreduction (CC) score, both low-grade and high-grade PMP patients were further divided into complete cytoreductive surgery (CRS) and maximal tumor debulking (MTD) subgroups. The ability to predict surgical resectability of total and selected PCI (regions 2 + 9 to 12) was analyzed through receiver operating characteristic (ROC) curves.

RESULTS

Both total and selected PCI demonstrated excellent discriminative ability in predicting surgical resectability for low-grade PMP patients (n = 266), with the ROC-AUC of 0.940 (95% CI: 0.904-0.965) and 0.927 (95% CI: 0.889-0.955). The corresponding optimal cutoff point was 21 and 5, respectively. For high-grade PMP patients (n = 100), both total and selected PCI exhibited good performance in predicting surgical resectability, with the ROC-AUC of 0.894 (95% CI: 0.816-0.946) and 0.888 (95% CI: 0.810-0.943); correspondingly, the optimal cutoff point was 25 and 8, respectively. The discriminative ability between total and selected PCI in predicting surgical resectability did not show a statistical difference.

CONCLUSIONS

Both total and selected PCI exhibited good performance and similarity in predicting complete surgical resection for both low-grade and high-grade PMP patients. However, the selected PCI was simpler and time-saving in clinical practice. In the future, new imaging techniques or predictive models may be developed to better predict PCI preoperatively, which might assist in confirming whether complete surgical resection can be achieved.

Origin and survival outcomes of Pseudomyxoma peritonei-A retrospective study

BACKGROUND

Pseudomyxoma peritonei (PMP) is an unusual clinical condition typically presenting with widespread mucinous neoplastic lesions within the peritoneum resulting in gelatin material-rich ascites. It was first described by Werth in 1884. Ever since, its clinical presentation, definition, site of origin, and prognosis have been a subject of debate. However, many histopathologic, immunohistochemical, and genetic studies have attempted to locate the primary lesion in the appendix in both genders.

OBJECTIVES

To analyze the histological origin and survival outcomes of pseudomyxoma peritonei in patients treated at a regional cancer center.

MATERIALS AND METHODS

Fifteen cases of PMP were diagnosed during the five-year study period. The demographic and clinicopathological details were retrieved; the slides were reviewed and histological parameters reassessed. Descriptive statistics were used to express proportions. Continuous variables were recorded as mean (SD) or median (IQR). Kaplan-Meier (KM) curve was used to estimate overall survival.

RESULTS

Mean age for PMP was found to be 47.5 years for low grade Mucinous Carcinoma Peritonei (MCP), 54.2 years for high grade MCP, and 58 years for high grade MCP with signet ring cells. Most common overall presentation was abdominal distension in 53.3% (8/15) of cases, followed by acute appendicitis in 20% (3/15) cases. PMP was detected synchronous with the primary tumor in 9/15 cases (60%). Primary lesion in the appendix was grossly identified in 7/15 cases, while it was not explored in the remaining eight cases. Yet, by combined clinical, radiological, histopathological, and immunohistochemical analysis, we identified that most of the cases (14/15) had an appendiceal origin (93.3%). The overall survival for 12 months was 50% and for 18 months was 37%.

CONCLUSION

The surgeon and radiologist may well bear in mind the most common possibility of an appendiceal origin for PMP and resect the appendix, irrespective of the presence of a grossly or radiologically detectable lesions. We emphasize that immunohistochemistry helped to detect the site of origin even when the primary was occult.

Recurrence after cytoreductive surgery and HIPEC for pseudomyxoma peritonei: A single-center retrospective cohort study

BACKGROUND AND AIMS

Pseudomyxoma peritonei (PMP) is a rare disease characterized by progressive build-up of mucinous deposits inside the abdominal cavity. The aim of this study was to investigate the effect of disease recurrence on overall survival in patients with PMP after cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

One-hundred thirty-two consecutive PMP patients treated with CRS + HIPEC at Helsinki University Hospital between 2008 and 2017 were included. The impact of clinicopathological and treatment-related characteristics on recurrence and overall survival was evaluated.

RESULTS

The median follow-up time in the study was 5.04 (range = 0.05-11.60) years. In 121 (91.7%) patients, the disease was classified as low grade and 11 (8.3%) had high-grade disease. In the low-grade group, 26 (21.5%) patients developed a recurrence during follow-up compared to 6 (54.5%) patients in the high-grade group. In the low-grade group, cumulative survival was 98.2%, 91.4%, and 91.4% at 3, 6, and 8 years, respectively. In the high-grade group, cumulative survival was 90.0% and 78.8% at 3 and 6 years, respectively. In patients with recurrent disease, the cumulative survival was 100%, 84.6%, and 84.6% at 3, 6, and 8 years in the low-grade category and 80.0% and 60.0% at 3 and 6 years in the high-grade category, respectively. In the low-grade group, a statistically significant correlation with recurrence but not with overall survival was identified with peritoneal cancer index (PCI), carcinoembryonic antigen (CEA), and the number of affected regions.

CONCLUSION

The recurrence of low-grade PMP does not significantly affect overall survival of patients. Disease extent may not be a prognostic indicator after curative CRS and HIPEC in low-grade PMP.

Combined ultrasonography and CT for prognosis and predicting clinical outcomes of patients with pseudomyxoma peritonei

OBJECTIVES

This study aimed to identify the diagnostic accuracy of combined ultrasonography (US) and computed tomography (CT) in evaluating the tumor burden of pseudomyxoma peritonei (PMP). Besides, we assessed the ability of this combination to predict the likelihood of complete resection.

METHODS

This retrospective study involved 504 patients diagnosed with PMP and scheduled for cytoreduction surgery. We compared tumor burden-quantified as peritoneal cancer index (PCI) by preoperative US and CT (US-CT-PCI)-with surgical findings. Next, we assessed the prognostic value of US-CT PCI and imaging features in determining the completeness of cytoreduction (CCR) score using multivariate analysis.

RESULTS

US-CT PCI demonstrated a high PCI evaluation accuracy under moderate tumor burden. Higher US-CT PCI could predict incomplete resection. In addition, we identified imaging features such as mesenteric involvement as an independent predictor of incomplete resection (hazard ratio (HR) = 2.006; p = 0.007).

CONCLUSIONS

US-CT PCI allowed us to predict the completeness of cytoreductive surgery in patients with PMP. Moreover, the combined US and CT imaging detected several features indicating incomplete cytoreduction.

KEY POINTS

• Ultrasonography (US) can act as a complementary diagnostic modality in peritoneal cancer index (PCI) evaluation by combining CT in the small bowel area and US in the abdominal area. • A modified peritoneal cancer index (US-CT PCI) helps preoperatively evaluate tumor burden with high accuracy and allows to predict incomplete resection. • US-CT PCI of 20 or above and the involvement of particular structures such as mesentery, independently indicate incomplete resection.

Prognostic value of the ascites characteristics in pseudomyxoma peritonei originating from the appendix

Background

Pseudomyxoma peritonei (PMP) is a rare disease, with the overall survival (OS) influenced by many factors. To date, no ascites characteristics have been reported to predict OS of patients with PMP. The present study therefore aims to describe the ascites characteristics for PMP and identify prognostic factors for survival.

Methods

Between June 2010 and June 2020, 473 PMP patients who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy were included in a retrospective study. Survival analysis was performed with the Kaplan-Meier method by the log-rank test and a Cox proportional hazards model. Associations between categorical variables were analyzed using the chi-squared test.

Results

Among all included patients, 61% were women. The median OS was 47 months (range, 4-124 months) at the last follow-up in December 2020. Ascites characteristics can be divided into light blood ascites, "Jelly" mucus ascites, and faint yellow and clear ascites. Multivariate Cox analysis showed that the degree of radical surgery, ascites characteristics, and pathological grade were independently associated with OS in PMP patients. The chi-squared test documented that faint yellow "Jelly" ascites were related to low-grade PMP and light blood ascites were associated with high-grade PMP (P < 0.01).

Conclusions

Light blood ascites, incomplete cytoreduction surgery, and high-grade histopathology may predict poor OS in appendix-derived PMP.

Rare Mucinous Adenocarcinoma of the Appendix Undergoing Multiple Recurrent Surgical Interventions

Primary appendiceal carcinomas are rare and often found incidentally when the appendix is surgically removed. Adenocarcinoma predominates the histological types of malignancies, with mucinous adenocarcinoma being the most prevalent of the various subtypes. Pseudomyxoma peritonei (PMP), a complication seen in mucinous adenocarcinoma of the appendix (MAA), is the collection of mucinous ascites in the intra-abdominal cavity and the thickening of the surrounding viscera by mucin-producing tumor cells. PMP initially presents with increased abdominal discomfort and girth and, in later stages, presents with obstructive abdomen symptoms. These symptoms are nonspecific and can be a challenge to pinpoint. Such was the case for our patient, in this case report, who initially presented with dyspepsia and later demonstrated compressive symptoms and weight loss, raising concern for malignancy. An appendiceal pathology was of concern when his right lower quadrant pain acutely worsened during an abdominal ultrasound, and imaging and biopsy confirmed MAA with PMP. The aim of this report is to shed light on the management of recurrent MAA. Our patient's recurrent MAA was managed with debulking procedures and three rounds of hyperthermic intraperitoneal chemotherapy (HIPEC) and was managed postoperatively with folinic acid, fluorouracil, and irinotecan (FOLFIRI) and bevacizumab, which in its totality helped achieve a progression-free survival of more than two years. We believe that cytoreduction and intraoperative chemotherapy prolong survival in patients with recurrent disease, as was the case with our patients. Our patient also demonstrated benefit as his disease stabilized after starting bevacizumab; however, more studies need to be performed at a larger scale to show a consistent relationship.

Pseudomyxoma peritonei originating from intestinal duplication: A case report and review of the literature

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare mucinous neoplasm with a relatively low incidence of 1 to 2 per million individuals. It is typically characterized by a type of gelatinous ascites named “jelly belly”. Most cases of PMP occur in association with ruptured primary mucinous tumors of the appendix (90%). Periodically, PMP can originate from mucinous carcinomas at other sites, including the colorectum, gallbladder, and pancreas. However, unusual origin can occur, as noted in this case report.

CASE SUMMARY

A 52-year-old woman had an unusual derivation of PMP from intestinal duplication. The patient complained of abdominal distension and increasing abdominal girth. Abdominal contrast-enhanced computed tomography showed a mass in the greater omentum located on the left side of the abdomen, likely to be a cystic mass of peritoneal origin. A PMP diagnosis was presumed based on the specific signs of the mass with flocculent and stripe-like echoes in ultrasound images. Ultrasound-guided percutaneous aspiration suggested a high likelihood of PMP. Once the PMP diagnosis was recognized, identification of the origin of the primary tumor was indicated. Thus, an exploratory laparoscopy was performed. In the absence of a primary tumor of appendix origin, the diagnosis of a low-grade mucinous neoplasm of intestinal duplication origin was finally confirmed by histopathology.

CONCLUSION

PMP is secondary to mucinous carcinomas of the appendix mostly. This case resulted from an unusual derivation from intestinal duplication.

Nomogram to Predict Incomplete Cytoreduction for Pseudomyxoma Peritonei

BACKGROUNDS

The completeness of cytoreduction is one of the most important prognostic factors for patients with pseudomyxoma peritonei (PMP). To date, no nomograms have been established to predict incomplete cytoreduction (IC) for patients with PMP. The current study therefore proposed a nomogram to predict individual IC risk for PMP patients.

METHODS

Between 1 June 2013, and 22 November 2019, 144 consecutive PMP patients who underwent cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for the first time in our center were included in a retrospective study. Possible predictors of cytoreducibility were analyzed using logistic regression modeling to predict IC for PMP patients. A nomogram was developed based on the multivariate analysis and further investigated for internal validation.

RESULTS

After CRS, the 144 participants were divided into complete CRS (CCRS) (n = 46) and IC (n = 98) subgroups. Four independent predictors (sex, disease duration, anemia, and carbohydrate antigen 19-9 (CA 199)) were included in the prediction model. Then, a nomogram predicting IC was established based on the aforementioned variables, which demonstrated good predictive accuracy (C-index, 0.837; 95 % confidence interval [CI], 0.764-0.894). The predicted probability was close to the actual observed outcome according to the calibration plot.

CONCLUSIONS

The current work led to the development of a nomogram capable of predicting IC for PMP patients who demonstrated good performance. Risk stratification by the established nomogram had ability to optimize individual IC prediction and help physicians to establish meticulous preoperative plans.

New insights in the pathology of peritoneal surface malignancy

Pathology is central to the management of peritoneal surface malignancy. This article highlights some recent advances that have had an impact on patient management or could do so in the near future. Malignant peritoneal mesothelioma, particularly the epithelioid subtype, is amenable to radical therapy in selected cases, and factors such as ki67 proliferation index, expression of BAP1 and mutation in CDKN2A show promise as prognostic indicators. Our understanding of multicystic mesothelioma has improved in recent years; it is a true neoplasm for which surgery may be indicated. Serous carcinomas involving the peritoneum are now known to originate from tubal epithelium. They are of two distinct types, high grade and low grade, which are now recognized as different neoplasms with distinctive features, oncogenesis and behavior. Pseudomyxoma peritonei (PMP) is an unusual condition that usually arises from an appendiceal mucinous neoplasm. Recent consensus in the classification and nomenclature of these lesions is discussed, including the distinction between low grade and high grade appendiceal mucinous neoplasms (HAMN), and the diagnostic criteria for appendiceal adenocarcinoma. PMP is divided into four prognostic groups: acellular mucin, low grade mucinous carcinoma peritonei, high grade mucinous carcinoma peritonei, and high grade mucinous carcinoma peritonei with signet ring cells. The pseudomyxoma microbiome is a promising area for clinical intervention but has been the subject of little research activity. Goblet cell adenocarcinoma (previously known as 'goblet cell carcinoid') is a distinctive type of appendiceal adenocarcinoma. Its behavior correlates with histologic features, but no general consensus for classification has been reached.

Severe Erosive Esophagitis Secondary to Gastric Outlet Obstruction Related to Pseudomyxoma Peritonei

Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by a mucin-producing tumor. PMP tumor cells migrate to abdominal and pelvic sites, eventually enveloping intra-abdominal organs and compressing the gastrointestinal tract. Patients with PMP are often asymptomatic in early stages of the disease, but in later stages develop symptoms including abdominal pain, acute abdomen, increased abdominal girth, vomiting, and bowel obstruction. Nonspecific symptoms combined with a relatively modest accuracy of imaging modalities frequently lead to delay in PMP diagnosis and treatment, thereby increasing morbidity. We present a case demonstrating severe erosive esophagitis as a result of PMP-associated gastric antrum compression.

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.).

Updates in Appendix Pathology: The Precarious Cutting Edge

Mucinous appendiceal tumors include low-grade appendiceal mucinous neoplasm, high-grade appendiceal mucinous neoplasm, and mucinous adenocarcinoma. Nonmucinous adenocarcinomas are less frequent. Recent consensus guidelines and the latest edition of the World Health Organization classification will allow consistent use of agreed nomenclature. Accurate diagnosis is important not only for patient management but also to allow comparison of results between centers and tumor registries. Serrated polyps are the most common benign polyp in the appendix. They need to be distinguished from low-grade appendiceal mucinous neoplasm, which can also mimic other benign conditions. Goblet cell adenocarcinomas are a distinctive type of appendiceal neoplasm.

Post-inflammatory mucosal hyperplasia and appendiceal diverticula simulate features of low-grade appendiceal mucinous neoplasms

Post-inflammatory mucosal hyperplasia and appendiceal diverticulosis simulate mucinous neoplasms, causing diagnostic confusion. Distinction between neoplasia and its mimics is particularly important since many authorities now consider all appendiceal mucinous neoplasms to be potentially malignant. The purpose of this study was to identify clinicopathologic and molecular features that may distinguish appendiceal mucinous neoplasms from non-neoplastic mimics. We retrospectively identified 92 mucinous lesions confined to the right lower quadrant, including 55 non-neoplastic examples of mucosal hyperplasia and/or diverticulosis and 37 low-grade neoplasms. Presenting symptoms, radiographic findings, appendiceal diameter, appearances of the lamina propria, non-neoplastic crypts, and epithelium, as well as mural changes were recorded. Twenty non-neoplastic lesions were subjected to KRAS mutational testing. Non-neoplastic appendices were smaller (p < 0.05) and more likely to present with symptoms of appendicitis (p < 0.05) than neoplasms. While post-inflammatory mucosal hyperplasia and diverticula often showed goblet cell-rich epithelium, extruded mucin pools, and patchy mural alterations with fibrosis, they always contained non-neoplastic crypts lined by mixed epithelial cell types and separated by lamina propria with predominantly preserved wall architecture. On the other hand, mucinous neoplasms lacked normal crypts (p < 0.05) and showed decreased lamina propria (p < 0.05) with diffusely thickened muscularis mucosae and lymphoid atrophy. Six (30%) non-neoplastic lesions contained KRAS mutations, particularly those containing goblet cell-rich hyperplastic epithelium. We conclude that distinction between neoplastic and non-neoplastic mucinous appendiceal lesions requires recognition of key morphologic features; KRAS mutational testing is an unreliable biomarker that cannot be used to assess biologic risk or confirm a diagnosis of neoplasia.

Pseudomyxoma Peritonei Secondary to a Primary Appendix Tumor: A Belly Full of Jelly

Pseudomyxoma peritonei (PMP) is a rare and life-threatening cancer of the abdominal peritoneum. Symptoms can be non-specific and ignorable for several years such that most cases are diagnosed during explorative surgery. The cornerstones of diagnosis and effective management are heightened awareness and clinical suspicion, timely recognition, and early referral to a specialist center for work-up and cytoreductive surgery. We report an interesting case of a patient with PMP who had successful cytoreductive surgery and heated intraperitoneal chemotherapy.

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.

The histopathological classification, diagnosis and differential diagnosis of mucinous appendiceal neoplasms, appendiceal adenocarcinomas and pseudomyxoma peritonei

The vermiform appendix is the primary site of several distinctive benign and malignant neoplasms. Some can produce the clinical syndrome of pseudomyxoma peritonei (PMP). A consensus on their terminology was reached by an international panel of pathologists and clinicians working under the auspices of the Peritoneal Surface Oncology Group International (PSOGI), and this review discusses the application of the PSOGI classification to routine reporting. We discuss diagnosis and differential diagnosis together with implications for patient management, covering low-grade appendiceal mucinous neoplasms, high-grade appendiceal mucinous neoplasms, serrated polyps, adenomas and adenocarcinomas. We do not cover goblet cell tumours or neuroendocrine neoplasms in this paper.

Feasibility of radical cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei of appendiceal origin

BACKGROUND AND AIMS

We analyzed the feasibility of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with pseudomyxoma peritonei.

MATERIAL AND METHODS

A prospective database comprised 90 consecutive patients with demonstrable pseudomyxoma peritonei collected during 48 months. These patients, referred to our unit for consideration for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy, received both cytoreductive surgery and hyperthermic intraperitoneal chemotherapy if possible. We evaluated the factors associated with a successful procedure.

RESULTS

Hyperthermic intraperitoneal chemotherapy was successfully delivered to 56 of 90 patients (62%) with demonstrable pseudomyxoma peritonei. Tumor morphology of low grade (p = 0.013), age under 65 years (p = 0.004), and serum carcinoembryonic antigen level under 5.0 µg/L (p = 0.003) were associated with successful administration of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Mean peritoneal cancer index was lower (18.9 vs 32.6, p < 0.001) and age was younger (54.3 vs 61.6, p = 0.003) in patients who underwent hyperthermic intraperitoneal chemotherapy than in patients who did not. Four patients had complete cytoreductive surgery alone, and 20 patients underwent palliative debulking, but 10 were ineligible for this operation.

CONCLUSIONS

Although the combination of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is currently suggested the standard practice for pseudomyxoma peritonei, not all patients are eligible for this protocol. In this study, hyperthermic intraperitoneal chemotherapy was suitable for 62% of patients with pseudomyxoma peritonei of appendiceal origin.

Pseudomyxoma peritonei: a clinical case of this poorly understood condition

BACKGROUND

Pseudomyxoma peritonei is an uncommon condition with an estimated incidence of one to two per million (worldwide) per year. It is characterized by the peritoneal deposition of mucinous tumors, most commonly of the appendix, and occasionally from the ovary, coupled by mucinous ascites.

CASE PRESENTATION

We report the case of a 76-year-old woman who presented with increased abdominal girth and dyspnea for 2 weeks. She was diagnosed as a case of pseudomyxoma peritonei. She was submitted to right oophorectomy, omentectomy, and pseudomyxoma debulking. The histology was compatible with a mucinous tumor of colorectal/appendicular origin. Chemotherapy was not administered because of her functional status. Two years and 8 months later, she refers with postprandial fullness and has moderate ascites.

Role of preoperative sonography in the diagnosis and pathologic staging of pseudomyxoma peritonei

OBJECTIVES

The purpose of this study was to analyze the sonographic features of pseudomyxoma peritonei and the ability of preoperative sonography to assess the pathologic grades of this disease.

METHODS

Nineteen patients with pseudomyxoma peritonei who underwent preoperative sonographic examinations were included (9 male and 10 female; age range, 31-70 years). Four patients presented with disseminated peritoneal adenomucinosis, 7 with peritoneal mucinous carcinomatosis with intermediate or discordant features (intermediate-grade disease), and 8 with peritoneal mucinous carcinomatosis. The sonographic characteristics, clinical features, and serum tumor marker levels were recorded and compared among the 3 grades.

RESULTS

Clinical symptoms and carcinoembryonic antigen, cancer antigen 125 (CA-125), CA-19-9, CA-724, and CA-153 levels were not significantly different among the 3 pathologic grades (P > .05). Ascites, scalloping of the visceral margin, invasive parenchymal nodules, and peritoneal masses were detected in all grades. Disseminated peritoneal adenomucinosis occurred without the finding of an omental cake. The presence of enlarged lymph nodes was more common in peritoneal mucinous carcinomatosis. The diagnosis of pseudomyxoma peritonei was made by preoperative sonography in 1 case. Four cases were diagnosed as ovarian mucinous cystadenoma with rupture. One case was diagnosed as a mucinous appendiceal cyst. Four cases were diagnosed as ascites or encapsulated effusion. One case was misdiagnosed as lymphoma. The others were diagnosed as celiac masses.

CONCLUSIONS

Preoperative sonography can be used to diagnose pseudomyxoma peritonei as long as radiologists are familiar with the imaging features. Although there are overlaps in the sonographic findings among the different grades, some features may aid in separating them.

Recurrent Incisional Hernia due to Pseudomyxoma Peritonei

Pseudomyxoma peritonei is a rare but challenging neoplastic disease which is characterized with intraperitoneal mucinous-gelatinous fluid accumulation. It rarely presents as a mass mimicking abdominal wall hernias A recurrent incisional hernia due to pseudomyxoma peritonei is presented here. A 60-year-old female patient had been operated on for a left mucinous ovarian cyst 20 cm in diameter in 1998. Mucinous material had disseminated into interloop spaces through the right subdiaphragmatic region. Total abdominal hysterectomy + bilateral salpingooophorectomy and peritoneal toilet had been performed. She was rehospitalized for abdominal distention and a 4 cm defect over the incision and underwent a hernia repair using polypropylene mesh in 2001. Abdominal distention recurred to give a rise to an incisional hernia in 2006. She was reoperated for decompression and repair, but nothing could be done because of sticky adhesions and the incision were simply closed. The patient was referred to our department for operation. A prosthetic hernia repair with 30 × 30 cm polypropylene mesh was performed. The patient was discharged on the postoperative 5th day following an uneventful recovery. However, she died of disseminated disease after 18 months.