Pseudomyxoma peritonei

Analysis of causes and prognostic impact of tube occlusion during hyperthermic intraperitoneal chemotherapy for appendiceal pseudomyxoma peritonei

BACKGROUND

Appendiceal pseudomyxoma peritonei (PMP), a rare tumor from mucinous appendiceal origins, is treated with Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC). However, tubing blockages during HIPEC treatment pose a common challenge, impeding the smooth progression of therapy. Few studies to date have explored the incidence and risk factors of tube occlusion during HIPEC in patients with appendiceal PMP, as well as its adverse impact on postoperative complications.

METHODS

From October 2017 to June 2023, a total of 80 patients with appendiceal PMP undergoing combined CRS and HIPEC were included in this study. Tubing blockage events were strictly defined, with patients experiencing blockages during HIPEC treatment allocated to the study group, while those with unobstructed perfusion were assigned to the control group. A comparative analysis was conducted between the two groups regarding post-HIPEC health assessments and occurrence of complications. Risk factors for luminal occlusion during closed HIPEC procedures were identified through univariate and multivariate analysis of data from 303 HIPEC treatments.

RESULTS

Tubing blockages occurred in 41 patients (51.3%). The study group experienced prolonged gastrointestinal decompression time (4.1 ± 3.0 vs. 2.5 ± 1.7 days, P = 0.003) and prolonged time to bowel movement (6.1 ± 2.3 vs. 5.1 ± 1.8 days, P = 0.022) compared to the control group. There was no significant difference in the incidence of complications between the two groups. The 1-year survival rate postoperatively was 97%, and the 3-year survival rate was 81%, with no association found between tubing blockage and poorer survival. Additionally, In 303 instances of HIPEC treatment among these 80 patients, tube occlusion occurred in 89 cases (89/303, 29.4%). Multivariable logistic regression analysis revealed age, diabetes, hypertension, and pathology as independent risk factors for tube occlusion.

CONCLUSION

Tubing blockages are a common occurrence during HIPEC treatment, leading to prolonged postoperative gastrointestinal functional recovery time. When patients are elderly and have concomitant hypertension and diabetes, along with a histological type of low-grade mucinous tumor, the risk of tube occlusion increases. However, this study did not find a significant correlation between tubing blockage and the incidence of postoperative complications or overall patient survival.

Outcomes following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal malignancies: 10 ​Year experience

INTRODUCTION

The treatment of peritoneal malignancies has evolved and select patients can undergo effective surgical therapies. Access to innovative oncology procedures can be improved if programs are developed within and outside of academic cancer centers. We report the creation of a high volume, comprehensive peritoneal malignancy program developed in a community center.

METHODS

A retrospective single-site study was conducted using registry data comprising all patients who underwent Cytoreductive Surgery (CRS) and Heated Intraperitoneal Chemotherapy (HIPEC) between October 2011-December 2021.

RESULTS

353 patients underwent CRS and HIPEC. 208 patients experienced in-hospital morbidity (58.9 ​%). Group comparison by disease site, PCI, and the completeness of cytoreduction demonstrated survival differences in mean overall survival and disease-free survival in 1-, 3- and 5-year ranges.

CONCLUSIONS

This study demonstrates that with a standardized protocol and a surgeon-led multidisciplinary team it is possible to offer safe outcome driven, complex oncologic surgery in a community-based cancer program.

Ultrasound-guided day-case wide-bore percutaneous mucin aspiration in advanced pseudomyxoma peritonei

AIM

To evaluate percutaneous ultrasound-guided day-case mucin aspiration in advanced pseudomyxoma peritonei (PMP) using a wide-bore drain with regards to its safety and efficacy.

MATERIALS AND METHODS

All patients who underwent percutaneous mucin aspiration for PMP between 2019-2021 at a single national peritoneal tumour service were included in this study. Under local anaesthesia, a suction-enabled 28-32 F catheter was used for drainage following wire-guided track dilatation. The volume drained and difference in abdominal girth pre- and post-procedure were measured. Patients graded difficulty in breathing and abdominal discomfort pre- and post-procedure. Histology reports were reviewed.

RESULTS

Sixteen patients received 56 percutaneous mucin aspirations between 2019-2021. The aetiology was a low-grade appendiceal mucinous neoplasm (LAMN) in 50% of patients. The mean amount of mucin drained was 7,320 ± 3,000ml (range 300-13,500 ml). The mean reduction in abdominal girth post-procedure was 12.2 ± 5 cm (range 0-27 cm). Only grade 1 complications were observed.

CONCLUSION

Percutaneous ultrasound-guided day-case aspiration of mucin for advanced and recurrent PMP using a wide-bore drain is a safe and effective procedure. It may be used in the palliative setting or as a bridge to surgery in the very symptomatic patient or if there is a reversible contraindication to surgery.

Intraperitoneal Chemotherapy for Unresectable Peritoneal Surface Malignancies

Malignancies of the peritoneal cavity are associated with a dismal prognosis. Systemic chemotherapy is the gold standard for patients with unresectable peritoneal disease, but its intraperitoneal effect is hampered by the peritoneal-plasma barrier. Intraperitoneal chemotherapy, which is administered repeatedly into the peritoneal cavity through a peritoneal implanted port, could provide a novel treatment modality for this patient population. This review provides a systematic overview of intraperitoneal used drugs, the performed clinical studies so far, and the complications of the peritoneal implemental ports. Several anticancer drugs have been studied for intraperitoneal application, with the taxanes paclitaxel and docetaxel as the most commonly used drug. Repeated intraperitoneal chemotherapy, mostly in combination with systemic chemotherapy, has shown promising results in Phase I and Phase II studies for several tumor types, such as gastric cancer, ovarian cancer, colorectal cancer, and pancreatic cancer. Two Phase III studies for intraperitoneal chemotherapy in gastric cancer have been performed so far, but the results regarding the superiority over standard systemic chemotherapy alone, are contradictory. Pressurized intraperitoneal administration, known as PIPAC, is an alternative way of administering intraperitoneal chemotherapy, and the first prospective studies have shown a tolerable safety profile. Although intraperitoneal chemotherapy might be a standard treatment option for patients with unresectable peritoneal disease, more Phase II and Phase III studies focusing on tolerability profiles, survival rates, and quality of life are warranted in order to establish optimal treatment schedules and to establish a potential role for intraperitoneal chemotherapy in the approach to unresectable peritoneal disease.

Comprehensive Understanding and Evolutional Therapeutic Schemes for Pseudomyxoma Peritonei: A Literature Review

Pseudomyxoma peritonei is an infrequent solid tumor in clinical practice. The low morbidity and deficient understanding of this mucus-secreting malignant disease increase the risks of delayed identification or uncontrollable deterioration. In quite a lot cases, patients go through complete cytoreduction surgery and hyperthermic intraperitoneal chemotherapy could receive a long time survival over 5 years. But the recurrence rate is also hard to overlook. Unlike other types of cancer, the standard treatment for this considerable groups has not been confirmed yet. With the advanced medical progression, studies have been carrying out based on pathogenesis, biological characters, and mutated gene location. All but a few get statistical survival benefits, let alone the breaking progress on research or therapeutic practice in the field. We try to give a comprehensive exposition of pseudomyxoma peritonei around the epidemiology, radiologic features, clinical manifestation, present treatment and promising schemes, hoping to arise much attention and reflection on the feasible solutions, especially for the recrudescent part.

Hyperthermic Intraperitoneal Chemotherapy: A Critical Review

Simple Summary

Patients with cancer of the digestive system or ovarian cancer are at risk of developing peritoneal metastases (PM). In some patients with PM, surgery followed by intraperitoneal (IP) chemotherapy has emerged as a valid treatment option. The addition of hyperthermia is thought to further enhance the efficacy of IP chemotherapy. However, the results of recent clinical trials in large bowel cancer have put into question the use of hyperthermic intraperitoneal chemotherapy (HIPEC). Here, we review the rationale and current results of HIPEC for PM and propose a roadmap to further progress.

Abstract

With increasing awareness amongst physicians and improved radiological imaging techniques, the peritoneal cavity is increasingly recognized as an important metastatic site in various malignancies. Prognosis of these patients is usually poor as traditional treatment including surgical resection or systemic treatment is relatively ineffective. Intraperitoneal delivery of chemotherapeutic agents is thought to be an attractive alternative as this results in high tumor tissue concentrations with limited systemic exposure. The addition of hyperthermia aims to potentiate the anti-tumor effects of chemotherapy, resulting in the concept of heated intraperitoneal chemotherapy (HIPEC) for the treatment of peritoneal metastases as it was developed about 3 decades ago. With increasing experience, HIPEC has become a safe and accepted treatment offered in many centers around the world. However, standardization of the technique has been poor and results from clinical trials have been equivocal. As a result, the true value of HIPEC in the treatment of peritoneal metastases remains a matter of debate. The current review aims to provide a critical overview of the theoretical concept and preclinical and clinical study results, to outline areas of persisting uncertainty, and to propose a framework to better define the role of HIPEC in the treatment of peritoneal malignancies.

Pseudomyxoma retroperitonei masquerading as a psoas abscess

A 52-year-old woman was referred to our department with multiple discharging sinuses and swelling in the right flank and iliac region for the past year. Ultrasound revealed a large collection in the right psoas muscle with the sinus tract reaching up to the skin in the right iliac region. Despite repeated attempts at drainage, the collection continued to increase in size. CT was requested and revealed a large heterogeneous irregular collection in the right psoas with fistulous communication with the cecum and skin with the erosion of the overlying ilium. Because of lack of vertebral involvement, enhancing internal septations, non-visualisation of the appendix and feculent material admixed with mucinous discharge from the sinus, pseudomyxoma retroperitonei secondary to ruptured mucinous neoplasm of the appendix was suspected. Mucoid material at the local site was sent for histopathology, which confirmed our suspicion. Our treatment plan after ileostomy was cytoreductive surgery along with adjuvant radiotherapy (40 Gy in 20 fractions) with chemotherapy (5-fluorouracil and folinic acid given for 30 weeks, once a week). However, after ileostomy, the patient refused further treatment, citing financial reasons.

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.

Predictors of Progression of Appendiceal Mucinous Neoplasm to Pseudomyxoma Peritonei

Appendiceal mucinous neoplasm (AMN) can present with a spectrum of disease. Predicting factors in development of pseudomyxoma peritonei (PMP) from AMN could aid in management and treatment. The aim of this study was to determine factors predictive of PMP from AMN. This was a retrospective multicenter study of all patients diagnosed with AMN from 2006-2017. Diagnosis of PMP was compared by (1) patient demographics, (2) tumor characteristics, and (3) surgery. Secondary end points were disease-specific survival (DSS) and overall survival (OS).One-hundred thirty-eight patients with AMN were identified. Thirty-six patients (26.1%) had a ruptured appendix at presentation, and 12 patients (8.7%) were diagnosed with PMP during the study period. Eight patients presented with PMP at the time of surgery. No demographic factors were predictive of PMP. Operative approach and extent of initial resection did not correlate with PMP. Tumor rupture at presentation was the only factor associated with PMP, though only 14% of patients who presented with simple rupture eventually progressed to PMP.OS was not different between those who were diagnosed with PMP and those who were not. DSS was significantly lower for the group diagnosed with PMP (P = .007). Tumor rupture at presentation did not influence OS or DSS. The only factor found to be significantly associated with PMP was tumor rupture at presentation. Diagnosis of PMP did not affect OS but did lead to decreased DSS.In conclusion, though a majority of patients who presented with rupture did not go on to develop PMP, tumor rupture at presentation was the only factor significantly associated with PMP. Diagnosis of PMP did not affect OS at 5 years. In patients with AMN who present with a ruptured appendix on final pathology, we recommended continued surveillance, though overall risk of PMP is relatively low.

Improved Outcome Prediction for Appendiceal Pseudomyxoma Peritonei by Integration of Cancer Cell and Stromal Transcriptional Profiles

In recent years, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have substantially improved the clinical outcome of pseudomyxoma peritonei (PMP) originating from mucinous appendiceal cancer. However, current histopathological grading of appendiceal PMP frequently fails in predicting disease outcome. We recently observed that the integration of cancer cell transcriptional traits with those of cancer-associated fibroblasts (CAFs) improves prognostic prediction for tumors of the large intestine. We therefore generated global expression profiles on a consecutive series of 24 PMP patients treated with CRS plus HIPEC. Multiple lesions were profiled for nine patients. We then used expression data to stratify the samples by a previously published “high-risk appendiceal cancer” (HRAC) signature and by a CAF signature that we previously developed for colorectal cancer, or by a combination of both. The prognostic value of the HRAC signature was confirmed in our cohort and further improved by integration of the CAF signature. Classification of cases profiled for multiple lesions revealed the existence of outlier samples and highlighted the need of profiling multiple PMP lesions to select representative samples for optimal performances. The integrated predictor was subsequently validated in an independent PMP cohort. These results provide new insights into PMP biology, revealing a previously unrecognized prognostic role of the stromal component and supporting integration of standard pathological grade with the HRAC and CAF transcriptional signatures to better predict disease outcome.

Pseudomyxoma peritonei: visceral scalloping on CT is a predictor of recurrence after complete cytoreductive surgery

OBJECTIVES

Pseudomyxoma peritonei (PMP) is characterized by peritoneal dissemination of gelatinous ascites following rupture of a mucinous tumor. Treatment by cytoreductive surgery (CRS) has improved its prognosis. Although visceral scalloping, notably liver scalloping, on computed tomography (CT) is a typical feature of PMP, its prognostic value remains unknown. We aimed to investigate the efficacy of liver scalloping in predicting recurrence in PMP patients.

METHODS

Among 159 consecutive patients with PMP who had contrast-enhanced CT between September 2012 and December 2018, 64 treatment-naïve patients who subsequently underwent CRS with complete resection (i.e., completeness of cytoreduction score (CC)-0 or CC-1), were included in analysis. Presence of liver scalloping and maximum thickness of mucin deposition at the liver surface were evaluated on CT. Disease-free survival (DFS) was determined based on the combination of postoperative CT features and tumor marker values.

RESULTS

Median follow-up was 24.3 months. CT revealed liver scalloping in 40/64 (63.4%) patients. Kaplan-Meier analysis showed significantly shorter DFS in patients with scalloping than in those without (p = 0.001; hazard ratio, 4.3). In patients with scalloping, greater mucin deposition (thickness ≥ 20 mm) significantly correlated with poorer DFS (p = 0.042). In multivariate Cox proportional hazards regression including CC status, pathologic type, and tumor markers, the presence of scalloping independently and significantly correlated with DFS (p = 0.031).

CONCLUSIONS

Liver scalloping was an independent predictor even after adjusting for clinical covariates. The presence of liver scalloping can lead to a high recurrence rate after CRS.

KEY POINTS

• The presence of liver scalloping is a prognostic factor independent of histological grade and tumor markers. • Greater mucin deposition (thickness ≥ 20 mm at the liver surface) is associated with higher recurrence rates in patients with liver scalloping.

Intraperitoneal chemotherapy for peritoneal metastases: an expert opinion

Introduction: The rationale for intraperitoneal (IP) drug delivery for patients with peritoneal metastases (PM) is based on the pharmacokinetic advantage resulting from the peritoneal-plasma barrier, and on the potential to adequately treat small, poorly vascularized PM. Despite a history of more than three decades, many aspects of IP drug delivery remain poorly studied.Areas covered: We outline the anatomy and physiology of the peritoneal cavity, including the pharmacokinetics of IP drug delivery. We discuss transport mechanisms governing tissue penetration of IP chemotherapy, and how these are affected by the biomechanical properties of the tumor stroma. We provide an overview of the current clinical evidence on IP chemotherapy in ovarian, colorectal, and gastric cancer. We discuss the current limitations of IP drug delivery and propose several potential areas of progress.Expert opinion: The potential of IP drug delivery is hampered by off-label use of drugs developed for systemic therapy. The efficacy of IP chemotherapy for PM depends on cancer type, disease extent, and mode of drug delivery. Results from ongoing randomized trials will allow to better delineate the potential of IP chemotherapy. Promising approaches include IP aerosol therapy, prolonged delivery platforms such as gels or biomaterials, and the use of nanomedicine.

Cost analysis of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy and the risk factors for their increased cost in a public insurance health care system - Single centre study

INTRODUCTION

This study aimed to evaluate the costs of CRS and HIPEC and treatment of the related postoperative complications in the public healthcare system. We also aimed to identify the risk factors that increase the cost of CRS and HIPEC.

MATERIALS AND METHODS

We retrospectively evaluated 80 patients who underwent CRS and HIPEC between February 2016 and November 2018 in the Department of Surgery, University Hospital of Olomouc, Czech Republic. Intraoperative factors and postoperative complications were assessed. The treatment cost included the surgery, hospital stay, intensive care unit (ICU) admission, pharmaceutical charges including medication, hospital supplies, pathology, imaging, and allied healthcare services.

RESULTS

The postoperative morbidity rate was 50%, and the mortality rate was 2.5%. The mean length of hospitalisation and ICU admission was 15.44 ± 8.43 and 6.15 ± 4.12 for all 80 patients and 10.73 ± 2.93 and 3.73 ± 1.32, respectively, for 40 patients without complications, and 20.15 ± 13.93 and 8.58 ± 6.92, respectively, for 40 patients with complications. The total treatment cost reached €606,358, but the total reimbursement was €262,931; thus, the CRS and HIPEC profit margin was €-343,427. Multivariate analysis showed that blood loss ≥1.000 ml (p = 0.03) and grade I-V Clavien-Dindo complications (p < 0.001) were independently associated with increased costs.

CONCLUSION

The Czech public health insurance system does not fully compensate for the costs of CRS and HIPEC. Hospital losses remain the main limiting factor for further improving these procedures. Furthermore, treatment costs increase with increasing severity of postoperative complications.

The many faces of pseudomyxoma peritonei: a radiological review based on 30 cases

Objective:

To determine the most common imaging features of pseudomyxoma peritonei (PMP), as well as the histologic subtypes of the primary tumors.

Materials and Methods:

We reviewed 30 cases of women with pathologically confirmed PMP. Only computed tomography scans were available. All cases were retrospectively studied by four radiologists, working independently. We identified the most common imaging findings, the predominant primary site of the disease, and the growth pattern. The most common sites of recurrence were also analyzed.

Results:

The most common computed tomography finding was peritoneal/omental nodules (including “omental caking”), followed by visceral scalloping and non-mucinous ascites. The most common site of the primary tumor was the appendix (in 63.3%), followed by the ovaries (in 16.6%), and 16.6% of the tumors were of undetermined origin. There was one case of synchronous appendiceal and ovarian tumors. Low-grade mucinous neoplasm was the most common histologic subtype, accounting for 84.2% of the appendiceal tumors and 40% of the ovarian tumors.

Conclusion:

Although PMP is a relatively rare entity, radiologists must be aware of its possible imaging findings, common locations, and possible patterns of recurrence. The origin of the primary tumor should also be investigated. Future studies are needed in order to determine which preoperative imaging findings predict surgical outcomes and to characterize the main findings of radiological recurrence.

An omental mass. Any idea?

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Pseudomyxoma peritonei, omental mass, review, abdominal pain, mucinous mass.

Introduction

Pseudomyxoma extraperitonei (PE) is a rare finding. The most common cause is the rupture of a mucocele of the appendix into the retroperitoneum.

Presentation of case

Here we report a case of a 52 years old female patient with a mass in the right abdomen and vague lower abdominal pain underwent resection of a extraperitoneal encapsulated mass. The histopathological examination revealed a mucinous pseudomyxoma with a low grade of differentiation.

Discussion

We report a case of pseudomyxoma extraperitonei with a review of literature.

Conclusion

The treatment of pseudomyxoma differs substantially depending on whether it is intraperitoneal or extraperitoneal. The risk of recurrence is such that follow-up, based on a physical examination, CT scan and serum markers, is essential.

[Recurrence of pseudomyxoma peritonei with liver and splenic metastases: about a case and literature review]

Le pseudo myxome péritonéal (PMP), est un syndrome clinicopathologique caractérisé par une ascite mucineuse et des pools de mucine comportant un épithélium mucineux néoplasique dans la cavité péritonéale. Le PMP est peu fréquent, et se présente avec des manifestations cliniques et pathologiques inhabituelles posant des problèmes diagnostic et thérapeutiques. L'atteinte des viscères abdominaux et les métastases ganglionnaires sont rares et se limitent à des cas sporadiques rapportes dans la littérature. Nous rapportons ici le cas d'un patient de 56 ans opéré à deux reprises pour PMP d'origine appendiculaire, et qui a consulté pour douleurs abdominales évolutives, cinque ans après sa dernière cure. Le scanner avait objective une récidive de pseudo myxome péritonéal, avec présence de lésions intraparenchymateuses spléniques et hépatique .l 'étude anatomopathologique avait objective la récidive d'un pseudo myxome péritonéal de bas grade avec la localisation intrasplénique et hépatique des mêmes lésions histologiques confirmant les métastases.

Prediction of Resectability in Pseudomyxoma Peritonei with a New CT Score

BACKGROUND

Curative treatment of pseudomyxoma peritonei (PMP) is complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC).

OBJECTIVE

The aim of this study was to build and evaluate a preoperative imaging score to predict resectability.

PATIENTS AND METHODS

Between 2007 and 2014, all PMP patients in two tertiary reference centers who underwent laparotomy with intent to undergo CRS and HIPEC were included in this study retrospectively. Thickness of tumor burden was measured on preoperative multidetector-row computed tomography (MDCT) by two radiologists blinded to surgical results in five predetermined areas. Patients were divided into two cohorts with the same resectability rate (building and validation). The performances of the scores were assessed using receiver operating characteristic (ROC) curve analyses.

RESULTS

Overall, 126 patients were included, with compete CRS being achieved in 91/126 patients (72.2%). Two cohorts of 63 patients matched by age, sex, burden of disease, resectability rate, and pathological grade were constituted. The MDCT score was the sum of the five measures, and was higher in unresectable disease [median 46.2 mm (range 27.9-74.6) vs. 0.0 mm (range 0.0-14.0), p < 0.001]. Area under the ROC curve was 0.863 (range 0.727-0.968) and 0.801 (range 0.676-0.914) in the building and validation cohorts, respectively. A threshold of 28 mm yielded a sensitivity, specificity, positive predictive and negative predictive value of 94, 81, 81 and 94% in the building cohort, and 80, 68, 59 and 85% in the validation cohort, respectively. Using our score, overall and disease-free survival were increased in the group classified as resectable.

CONCLUSION

A simple preoperative MDCT score measuring tumor burden in the perihepatic region is able to predict resectability and survival of PMP patients.

Adnexal masses associated with peritoneal involvement: diagnosis with CT and MRI

Given the unique intra-peritoneal anatomic location of the adnexa, tubo-ovarian diseases can commonly spread into the peritoneal cavity. Peritoneal seeding may occur in a spectrum of adnexal conditions including infectious diseases, endometriosis, and benign or malignant primary or secondary ovarian tumors. CT is usually the imaging modality on which the concomitant involvement of the peritoneum and the ovary is depicted. The first diagnosis to be considered by the radiologist is generally peritoneal carcinomatosis from ovarian cancer but other conditions cited above have also to be borne in mind and may be suggested on the basis of careful assessment of CT findings or on further MR findings. MRI may indeed help characterize the lesions in some cases. The purpose of this review is to describe the clinical and imaging patterns of peritoneal involvement that may be found in association with different ovarian lesions. Familiarity with these patterns and diagnoses will help the radiologist narrow the differential diagnosis and make an accurate diagnosis, thus facilitating patient management and avoiding unnecessary invasive treatment.

Detection and management of retroperitoneal cystic lesions: A case report and review of the literature

The identification of cystic lesions within the retroperitoneal space is a rare event that poses clinicians the challenge of a difficult diagnosis and disease management. Retroperitoneal cystic lesions account for a group of lesions that range from common benign lesions (e.g., lymphoceles developing as a surgical complication) to rare aggressive malignant neoplasms. Currently, in the majority of cases, image-guided procedures allow for a pathological diagnosis to be achieved in these challenging lesions, thus offering the chance of an appropriate treatment; however, the overall clinical assessment of retroperitoneal cysts is highly demanding. The present study reports the management of a representative clinical case, presenting with a voluminous cystic mass able to dislocate cave vein, whose diagnosis was preceded by a deep vein thrombosis. Computed tomography-scan and ultrasound guided percutaneous drainage were performed to achieve the diagnosis. Following the discussion of the current case report, a review of the pathological and radiological characteristics of retroperitoneal cystic lesions is presented.

KRAS and GNAS Co-Mutation in Metastatic Low-Grade Appendiceal Mucinous Neoplasm (LAMN) to the Ovaries: A Practical Role for Next-Generation Sequencing

Patient: Female, 49

Final Diagnosis: Metastatic LAMN

Symptoms: Abdominal discomfort

Medication: —

Clinical Procedure: Laparoscopic total abdominal hysterectomy • bilateral salpingo-oophorectomy • complete supracolic omentectomy • appendectomy

Specialty: Oncology

Repeat cytoreductive surgery with or without perioperative intraperitoneal chemotherapy for peritoneal surface malignancy

BACKGROUND

A significant proportion of patients with peritoneal surface malignancy (PSM) experienced recurrence after initial cytoreductive surgery (CRS). Thus the aims of this study were to determine short-term outcomes and long-term survivals associated with repeat CRS.

METHODS

This was a retrospective study of prospectively collected data of consecutive patients with PSM who underwent CRS by one surgical team at St George Hospital in Sydney, Australia between Jan 1996 and May 2016.

RESULTS

There was no significant difference in hospital mortality (p=0.343) and major morbidity rate (p=0.454). Patients who underwent repeat surgery had a significantly higher 5-year overall survival (OS) rate (p<0.001) and a longer median disease free interval (DFS) (p<0.001). Repeat CRS was also found to be a significant prognostic factor for OS (p<0.001) and DFS (p<0.001).

CONCLUSIONS

Repeat CRS with or without perioperative intraperitoneal chemotherapy could provide long-term survival benefits to patients with PSM with acceptable mortality and morbidity rates.

SUMMARY

1. Repeat CRS with or without PIC provides long-term survival benefits to patients with PSM. 2. Repeat CRS with or without PIC is feasible and can be performed without acceptable mortality and morbidity rates.

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.

Pathologic diagnosis, origin, and natural history of pseudomyxoma peritonei

Mucinous ascites and pools of mucin within the peritoneal cavity associated with neoplastic, mucinous epithelium are the characteristic features of pseudomyxoma peritonei (PMP). Clinically, PMP presents with abdominal distension and gelatinous ascites. In female patients, pelvic masses can be seen. Radiologic findings on computed tomography include scalloping of the hepatic and splenic margins and dense ascites. Surgically, PMP is encountered as grossly visible mucin in the peritoneal cavity. The presence of mucin outside of the appendix, in the right lower quadrant, and beyond is an important diagnostic finding. The appendix may be distended or ruptured. In women, there is often bilateral surface involvement of the ovaries, raising the differential diagnosis of primary ovarian neoplasms; however, these are extremely rare causes of PMP. Because of the association between appendiceal lesions and metastatic mucinous neoplasms of the ovary, appendectomy in the setting of any mucinous peritoneal or ovarian process may be prudent, even if the appendix is grossly normal. The gastrointestinal tract, especially the hepatopancreato biliary system, also needs to be assessed by the surgeon. Pathologically, PMP arises almost exclusively from low- or high-grade mucinous neoplasms of the appendix. These neoplasms must be distinguished both from rare benign causes of mucinous ascites and from nonappendiceal primary tumors. PMP has a protracted clinical course with progressive fibrous adhesions and obstructive disease; aggressive surgical and cytoreductive therapy with hyperthermic intraperitoneal chemotherapy has been reported to improve clinical outcomes.

Giant Intraperitoneal Multiloculated Pseudocyst in a Male

Intraperitoneal pseudocysts are rare and may be difficult to differentiate from other malignant neoplasms. Reports of occurrences are mainly associated with long-term intraperitoneal catheter use, intraperitoneal catheter infections, or major pelvic surgery in females, although there are few reported incidences without prior trauma. We present a case of a male patient found to have a 19 × 15 × 9 cm intraperitoneal pseudocyst with other multiloculated areas and a history of a right inguinal hernia repair. After a thorough review of the literature, this is the first multiloculated nonpancreatic pseudocyst reported in a male patient.

Pseudomyxoma Peritonei: Symptom Control and Objective Radiological Response after Treatment with Lanreotide Autogel

Peritoneal mucinous carcinomatosis is an aggressive subtype of pseudomyxoma peritonei, which often leads to inoperable bowel obstruction and, ultimately, death. Due to the poor prognosis, treatment is often symptomatic and aimed at alleviating the symptoms – pain, nausea, and vomiting – associated with gastrointestinal obstruction. Due to their antisecretory activity, somatostatin analogues are commonly prescribed in such cases. In the case presented here, a patient diagnosed with disseminated peritoneal mucinous carcinomatosis of appendiceal origin responded well to symptomatic treatment with lanreotide Autogel^® at a dose of 120 mg/28 days. More importantly, radiological evidence of a reduction in peritoneal ascites, indicative of antiproliferative activity, was observed. These findings are important, particularly given the negative impact of this disease on both quality of life and survival. This case adds to the growing body of evidence supporting the antiproliferative and antisecretory activity of lanreotide Autogel.

Pseudomyxoma peritonei extending to the lower extremity: a case report

Pseudomyxoma peritonei is characterized by mucinous ascites originating from a mucin-producing neoplasm; however, even the definition is still under debate. Tumor deposits extend and ultimately engulf the entire cavity, causing death from cachexia due to limited intestinal movement. Here, we report a unique case of an 80-year-old woman with pseudomyxoma peritonei, which extended to the lower extremity mimicking infectious condition. The patient survived for a long time without bowel obstruction despite having the histologic subtype that has an unfavorable prognosis. The extremity lesion was treated with limited extensive surgery. The origin of the disease and the mechanism of extension to the extremity could not be clarified. Clinicians should be aware of the original disease entity and this unusual presentation and determine its mechanism and the best management strategy.

Secreted mucins in pseudomyxoma peritonei: pathophysiological significance and potential therapeutic prospects

Pseudomyxoma peritonei (PMP, ORPHA26790) is a clinical syndrome characterized by progressive dissemination of mucinous tumors and mucinous ascites in the abdomen and pelvis. PMP is a rare disease with an estimated incidence of 1-2 out of a million. Clinically, PMP usually presents with a variety of unspecific signs and symptoms, including abdominal pain and distention, ascites or even bowel obstruction. It is also diagnosed incidentally at surgical or non-surgical investigations of the abdominopelvic viscera. PMP is a neoplastic disease originating from a primary mucinous tumor of the appendix with a distinctive pattern of the peritoneal spread. Computed tomography and histopathology are the most reliable diagnostic modalities. The differential diagnosis of the disease includes secondary peritoneal carcinomatoses and some rare peritoneal conditions. Optimal elimination of mucin and the mucin-secreting tumor comprises the current standard of care for PMP offered in specialized centers as visceral resections and peritonectomy combined with intraperitoneal chemotherapy. This multidisciplinary approach has reportedly provided a median survival rate of 16.3 years, a median progression-free survival rate of 8.2 years and 10- and 15-year survival rates of 63% and 59%, respectively. Despite its indolent, bland nature as a neoplasm, PMP is a debilitating condition that severely impacts quality of life. It tends to be diagnosed at advanced stages and frequently recurs after treatment. Being ignored in research, however, PMP remains a challenging, enigmatic entity. Clinicopathological features of the PMP syndrome and its morbid complications closely correspond with the multifocal distribution of the secreted mucin collections and mucin-secreting implants. Novel strategies are thus required to facilitate macroscopic, as well as microscopic, elimination of mucin and its source as the key components of the disease. In this regard, MUC2, MUC5AC and MUC5B have been found as the secreted mucins of relevance in PMP. Development of mucin-targeted therapies could be a promising avenue for future research which is addressed in this article.

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.

Whole abdominopelvic radiotherapy in the palliative treatment of pseudomyxoma peritonei

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare clinical syndrome characterized by mucinous peritoneal disease arising from disseminated peritoneal adenomucinosis. Primary treatment involves a combination of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). There is no consensus on the proper treatment of recurrent PMP. In selected patients, repeated cytoreductive surgery with or without HIPEC might improve outcome. However, every repeated debulking procedure becomes less effective with increased morbidity.

CASE REPORT

We present a case of a patient with intestinal obstruction caused by recurrent pseudomyxoma peritonei. We treated the patient with whole abdominopelvic radiotherapy (WAPRT) using intensity-modulated arc therapy (IMAT) to a total dose of 33 Gy, delivered in 22 daily fractions. The treatment was well tolerated and resulted in resolution of the obstruction for a period of 24 months.

CONCLUSION

To the best of our knowledge, we present the first case report showing the possibility of resolving intestinal obstruction with WAPRT in a patient with recurrent PMP. It is our opinion that WAPRT delivered by IMAT, in analogy with ovarian cancer, should be considered as a palliative treatment option in managing patients with recurrent PMP especially in case of obstruction.

[Complications of presumed benign ovarian tumors]

The main risk factor of adnexal torsion is a previous adnexal torsion (LE3). There is no clinical, biological or radiological sign that may exclude the diagnosis of adnexal torsion (LE3). The presence of flow at color Doppler imaging does not allow exclusion of the diagnosis (LE2). An emergent laparoscopy is recommended for adnexal untwisting (Grade B), except in postmenopausal women where oophorectomy is recommended (grade C). A persistent black color of the adnexa after untwisting is not an indication for systematic oophorectomy (grade C), since a functional recovery is possible (LE3). Ovariopexy is not routinely recommended following adnexal untwisting (grade C). The clinical signs of intra-cystic hemorrhage and those of rupture of the corpus luteum are not specific (LE4). MRI is not recommended to confirm the diagnosis of intra-cystic hemorrhage (grade C). Malignant transformation of an ovarian cyst is very rare. The presence of a benign ovarian cyst is not associated with an increased risk of ovarian cancer at long-term follow-up (LE2). For these women, an ultrasound follow-up is not recommended (grade C). Dermoid ovarian cyst containing nerve tissue can trigger the production of pathogenic auto-antibody-anti-NMDA, leading to encephalitis. A high proportion of thyroid tissue in a mature teratoma (struma ovarii) may cause hyperthyroidism.

Different medical expenses incurred by appendiceal cystadenoma in China: Report of three cases

Appendiceal cystadenoma, the most common type of what has been generally termed 'mucocele' of the appendix, has unique clinical characteristics. In this study, three similar clinical manifestations of appendiceal cystadenoma are presented, with different subsequent management and diverse prognostic outcomes relating to the characteristics of the disease, the wishes of the patients, the medical workers and social factors. In this study, we provide details of three cases of appendiceal cystadenomas.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in Asian patients: 100 consecutive patients in a single institution

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been shown to improve survival in selected patients with peritoneal carcinomatosis. We review our institutional experience with the procedure and evaluate the overall survival (OS) and disease-free survival (DFS) rates in 100 consecutive patients.

METHODS

Data were prospectively collected from 100 consecutive patients with peritoneal carcinomatosis treated by CRS and HIPEC at the National Cancer Centre Singapore between April 2001 and May 2012. Our primary end points were OS and DFS.

RESULTS

Of the 100 patients, 84 were of Chinese ethnicity, 3 were Malay, 6 were Indian, and 7 were of other ethnicities. Primary tumors were ovarian cancer (n=39), colorectal cancer (n=28), primary peritoneal (n=6), appendiceal cancer (n=20), and mesothelioma (n=7). Median follow-up duration was 21 months. At 5 years, the DFS was 26.3% and OS was 50.9%. Factors influencing OS and DFS were cytoreductive score, primary cancer, and disease-free interval of more than 12 months on univariate analysis. The only factors that remained significant for prognosis after multivariate analysis were primary cancer and cytoreductive score. Thirty-day morbidity was 56%, and there were no 30-day mortalities.

CONCLUSIONS

CRS and HIPEC can be safely carried out in Asian patients with peritoneal carcinomatosis from ovarian, colorectal, appendiceal, mesothelioma, and primary peritoneal origins. Overall, the ovarian, appendiceal, mesothelioma, and primary peritoneal cancer patients tended to do better than the colorectal patients, but careful patient selection ensuring that optimal cytoreduction can be achieved is essential for the success of this procedure.

Pseudomyxoma Peritonei: A Rare Cause of Oliguric Acute Kidney Injury

Pseudomyxoma peritonei is a rare clinical condition that causes the accumulation of mucinous ascites, which gradually results in the compression of intra-abdominal organs. Most published reports of pseudomyxoma peritonei concern the mass effect of the resulting ascites, which presents as abdominal pain or intestinal ileus in severe cases. However, few reports of renal complications of the disease have been published. Here, we present a case of oliguric acute kidney injury caused by external compression by pseudomyxoma peritonei. After decompression with external drainage, the patient's renal function rapidly improved.

Pseudomyxoma peritonei of 92 Chinese patients: Clinical characteristics, pathological classification and prognostic factors

AIM: To assess the clinicopathologic features and its relationship with prognosis of pseudomyxoma peritonei (PMP) in Chinese patients.

METHODS: The clinicopathologic features and follow-up data of 92 patients with PMP were reviewed and retrospectively analyzed. The cases were categorized into three groups: disseminated peritoneal adenomucinosis (DPAM), peritoneal mucinous carcinomatosis (PMCA), and peritoneal mucinous carcinomatosis with intermediate or discordant features (PMCA-I/D). The log-rank test was used to analyze survival for each group and various clinicopathological parameters. Multivariate Cox proportional-hazard models were constructed to determine the important factors associated with survival.

RESULTS: The median age at diagnosis was 51.9 years (range: 22-76 years). The median follow up was 124 mo. The 3-, 5- and 10-year survival rates were 74.0%, 67.4% and 49.1%, respectively. There were 49 (53.2%) patients with DPAM, 26 (28.3%) with PMCA-I and 17 (18.5%) with PMCA. Patients with DPAM, PMCA-I/D and PMCA exhibited statistically significant difference in survival (P = 0.001). The 3 year survival for DPAM, PMCAI/D and PMCA was 97.0%, 80.0% and 67.0%, respectively; the 5 year survival was 80.0%, 67.0% and 50.0%, respectively; and the 10 year survival was 65.0%, 28.0% and 14.0%, respectively. Survival rate was significantly lowest in patients < 40 age years of age (P = 0.011). Appendiceal tumor and extra-ovarian parenchymal organ involvement were significantly related to overall survival. Patients with appendiceal mucinous adenocarcinoma (MACA) showed the significantly poorer prognosis (P = 0.011). Multivariate analysis showed that pathological classification, age, appendiceal tumor were significant related to overall survival.

CONCLUSION: The clinical process “PMP” should be pathologically classified into DPAM, PMCA and PMCA-I/D. Pathological classification, age, appendiceal MACA are survival independent predictors in Chinese patients with PMP.

[Peritoneal pseudomyxoma presenting as ascites in a patient with cirrhosis]

We present the case of a cirrhotic patient with ascites and an albumin gradient of less than 1.1 g/dl. After endoscopic tests, including upper gastrointestinal endoscopic ultrasound-guided fine-needle aspiration, exploratory laparoscopy was performed to provide the diagnosis, revealing mucin throughout the peritoneal cavity and nodules on the parietal and visceral peritoneum. Histopathological analysis established the diagnosis as peritoneal pseudomyxoma. This uncommon entity, which has a poor prognosis without treatment, is most frequently associated with mucinous tumors of the appendix, and secondly, with tumors of the ovary.

Mucinous adenocarcinomas with intra-abdominal dissemination: a review of current therapy

Peritoneal carcinomatosis has been considered a terminal disease with a median survival time of 5.2-12.6 months. Systemic chemotherapy and cytoreductive surgery (CRS) have long been used to treat macroscopic disease, with limited success. However, a comprehensive treatment approach involving cytroreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) has evolved into a novel approach for peritoneal carcinomatosis. Surgery removes the primary cancer and any dissemination within the peritoneal cavity and adjuvant HIPEC eradicates macroscopic or microscopic tumor residue, thus reducing the risk for recurrence. This approach offers a new potential treatment option for patients with metastatic disease confined to the peritoneum. The present review provides an update of the most recent data on the current therapy for pseudomyxoma peritonei (PMP) and mucinous colorectal adenocarcinoma (MCA) with metastatic disease confined to the peritoneum.

Peritoneal-based Malignancies and Their Treatment

Introduction: Patients with peritoneal carcinomatosis (PC) usually have dismal prognoses, even with traditional systemic therapy. Peritonectomy or cytoreductive surgery (CRS) has been used to treat selected patients. It is also commonly used in the management of pseudomyxoma peritonei (PMP), often in combination with hyperthermic intraperitoneal chemotherapy (HIPEC). Methods and Results: In the present review article, the indications for CRS and HIPEC are examined, along with its technical aspects, resulting morbidity and mortality. Patients with documented peritoneal carcinomatosis from colorectal and ovarian cancer or PMP, absence of extra-abdominal metastases and liver parenchymal metastases and with an ECOG performance status of <2 should be considered for CRS and HIPEC. Conclusion: It is important to recognise the role of and indications for CRS and HIPEC. Biologic factors of the disease and completeness of resection are important prognostic factors. Cytoreductive surgery, combined with intraperitoneal chemotherapy, can improve survival in selected patients with peritoneal-based malignancies. Key words: Cytoreductive surgery, Intraperitoneal chemotherapy, Peritonectomy, Peritoneal carcinomatosis, Pseudomyxoma peritone

Experience with adjuvant chemotherapy for pseudomyxoma peritonei secondary to mucinous adenocarcinoma of the appendix with oxaliplatin/fluorouracil/leucovorin (FOLFOX4)

Background

Pseudomyxoma peritonei (PMP) is a rare condition characterized by mucinous tumors, disseminated intra-peritoneal implants, and mucinous ascites. So far its diagnosis remains challenging to most clinicians.

Case presentation

A 55-year-old male patient had suffered from acute onset of abdominal pain and abdominal distension for one day prior to his admission. Physical examination revealed tenderness over the right lower quadrant of the abdomen without diffuse muscle guarding. A large amount of ascites was identified by abdominal computed tomography (CT) scan. Paracentesis showed the appearance of sticky mucinous ascites. He underwent laparotomy under the impression of pseudomyxoma peritonei. There was a lot of mucinous ascites, one appendiceal tumor and multiple peritoneal implants disseminated from the subphrenic space to the recto-vesicle pouch. Pseudomyxoma Peritonei caused by mucinous adenocarcinoma of appendiceal origin, was confirmed by histopathology. We performed an excision of the appendiceal tumor combined with copious irrigation and debridement. After the operation, he received 10 cycles of systemic chemotherapy with FOLFOX4 regimen, without specific morbidity. Follow-up of abdominal CT and colonoscopy at post-operative 17 months showed excellent response without evidence of local recurrence or distal metastasis. He made an uneventful recovery (up to the present) for 21 months after the operation.

Conclusion

This case report emphasizes the possible new role of systemic chemotherapy in the treatment of patients with this rare clinical syndrome.