Outcome differences between debulking surgery and cytoreductive surgery in patients with Pseudomyxoma peritonei

Two-stage cytoreductive surgery for 'extensive' pseudomyxoma peritonei: A legitimate alternative or salvage strategy?

BACKGROUND AND AIM

Two-stage cytoreductive surgery (CRS) has been proposed as an alternative to one-stage surgery in patients who have 'extensive' pseudomyxoma peritonei (PMP) and/or are unfit for very extensive surgery, to reduce morbidity. We review current evidence on two-stage CRS focusing on patient selection, interval between procedures, extent of surgery, use of HIPEC, perioperative and oncological outcomes.

METHODS

This is a narrative review. A literature search on PubMed and Embase was performed using keywords- 'Two-stage cytoreductive surgery', 'pseudomyxoma peritonei', 'high-volume PMP', 'huge PMP', 'cytoreductive surgery', 'HIPEC', 'staged surgery' and 'extensive pseudomyxoma peritonei'.

RESULTS

Five studies reported outcomes in a total of 114 patients. The indications for two-stage CRS were: in two studies, patients undergoing an incomplete cytoreduction due to undue surgical risk were reevaluated for a second surgery during routine surveillance; severe comorbidities in one; extensive disease with PCI>28 in another and in one, only HIPEC was performed as a second procedure due to intraoperative hemodynamic instability (the two-stage procedure was performed in interest of patient's safety). Major morbidity ranged from 0 to 37.5 % (first-stage) and 25%-38.9 % (second-stage). Short term follow-up demonstrated equivalent short-term oncological outcomes compared to historical data. Long term follow-up and quality-of-life data were not available.

CONCLUSIONS

The published studies showed different interpretations and applications of the two-stage CRS concept. The reported morbidity was similar to that after single-stage CRS for extensive PMP. Though short-term survival outcomes are acceptable, long-term follow-up is needed. Planned two-stage CRS should currently be reserved for highly selected clinical situations.

Long-term outcomes and survival analysis of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy in patients with pseudomyxoma peritonei at a newly established peritoneal malignancy centre in Japan

Background

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is established in the management of pseudomyxoma peritonei (PMP), selected cases of peritoneal mesothelioma, and resectable colorectal or ovarian peritoneal metastases in Western countries. However, the efficacy and feasibility of these techniques are not well established in the Asian population, and little has been reported on long-term survival outcomes for surgically resected PMP patients.

Materials and Methods

Retrospective analysis of a prospective database of short- and longer-term outcomes of consecutive patients who underwent CRS and HIPEC for PMP in a newly established peritoneal malignancy unit in Japan between 2010 and 2016.

Results

A total of 105 patients underwent CRS and HIPEC and 57 maximal tumor debulking (MTD) for pseudomyxoma peritonei. In the CRS group, the primary tumor was appendiceal in 94 patients (90%) followed by ovarian and colorectal. Major postoperative complications occurred in 22/105 patients (21%) with one in-hospital mortality (0.9%). The 5-year overall and disease-free survival rates for the CRS group were 74.2% and 50.1%, respectively. Multivariate analysis revealed unfavorable histology to be the significant predictor of reduced overall and disease-free survival. Completeness of cytoreduction, CA19-9, and CA125 were also associated with disease-free survival.

Conclusions

This is the first report on long-term outcomes and survival analysis of CRS and HIPEC for PMP in the Asian population. CRS and HIPEC can be conducted with reasonable safety and favorable survival in a new center. Complete tumor removal and histological type are the strongest prognostic factors for both overall and disease-free survival.

Pseudomyxoma peritonei leading to "jelly belly" abdomen: a case report and review of the literature

BACKGROUND

Pseudomyxoma peritonei is an infrequent condition with a global annual incidence of only one to two cases per million people. Mucinous neoplasms, widespread intraperitoneal implants, and mucinous ascites characterize it. Currently, most clinicians misdiagnose this condition, which leads to delayed management.

CASE PRESENTATION

A 44-year-old North Indian female presented with a 1.5-month history of an abdominal lump. Physical examination revealed a sizeable abdominopelvic mass at 36 weeks. Contrast-enhanced computed tomography showed a massive multiloculated right ovarian cystic mass measuring 28 × 23 × 13 cm with mild ascites and elevated carcinoembryonic antigen levels (113.75 ng/ml). A provisional diagnosis of ovarian mucinous neoplasm was made, for which the patient underwent laparotomy. Intraoperatively, there were gross mucinous ascites, along with a large, circumscribed, ruptured right ovarian tumor filled with gelatinous material. The appendicular lump was also filled with mucinous material along with the omentum, ascending colon, right lateral aspect of the rectum, splenic surface, and small bowel mesentery. Cytoreductive surgery was performed along with an oncosurgeon, including total abdominal hysterectomy with bilateral salpingoophorectomy, omentectomy, right hemicolectomy, lower anterior resection, ileo-transverse stapled anastomosis with proximal ileal loop diversion stoma, excision of multiple peritoneal gelatinous implants, and peritoneal lavage. Histopathology and immunohistochemistry confirmed the presence of intestinal-type mucinous carcinoma. Postoperatively, the patient was given six cycles of chemotherapy. She tolerated it without any specific morbidity and had an uneventful recovery. Postoperative follow-up at 15 months revealed normal tumor marker levels and abdominal computed tomography findings and no signs suggestive of local recurrence or distal metastases.

CONCLUSIONS

Pseudomyxoma peritonei is a rare disease that is frequently misdiagnosed in the preoperative phase. Therefore, radiologists and clinicians should maintain a high index of suspicion for accurate diagnosis and multidisciplinary management.

[Incidental finding of appendiceal mucinous neoplasms]

Low-grade appendiceal mucinous neoplasms (LAMN) are rare and are diagnosed in at least 0.13% of appendectomies in Germany, although significant underreporting is likely. Perforation of the tumors can result in abdominal mucinous collections, so-called pseudomyxoma peritonei (PMP). The challenge in the treatment of LAMN is the adequate approach to the incidental finding of these tumors. If a mucinous neoplasm is preoperatively suspected in cases of an acute condition, usually appendicitis, it must be weighed up whether a conservative approach is justifiable or whether immediate appendectomy is necessary. If this is the case, an intraoperative perforation of the appendix must be avoided and the complete abdominal cavity must be inspected for mucin deposits. If conservative treatment is possible, further treatment should take place at a specialized center. If the neoplasm is first found incidentally during surgery, perforation of the appendix should also be avoided and the entire abdominal cavity should be inspected for a PMP. If a PMP is present cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) should be performed in a specialized center. If LAMN are found during the postoperative histological work-up, it should be evaluated whether a perforation was present and mucin collections are noted in the surgical report. In the case of LAMN without evidence of a PMP, appendectomy is the adequate treatment. In cases of intra-abdominal mucinous collections, samples should be taken and further treatment should be performed at a center with sufficient expertise. An ileocecal resection or oncological hemicolectomy is not indicated. After adequate treatment, all patients should receive a follow-up using cross-sectional imaging (preferably magnetic resonance imaging, MRI) and determination of the tumor markers CEA, CA 19-9 and CA 125.

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.

The role of chemotherapy in the treatment of advanced appendiceal cancers: summary of the literature and future directions

Appendiceal cancer is rare and encompasses a diverse group of tumours ranging from low-grade appendiceal mucinous neoplasms to high-grade adenocarcinomas. Appendiceal cancers often spread to the peritoneal cavity causing extensive mucinous dissemination and peritoneal metastases. Prognosis varies with histological subtype. Cytoreductive surgery and heated intraperitoneal chemotherapy is well-established as the most effective treatment achieving long-term survival in some patients. Chemotherapy regimens used to treat appendiceal cancer are extrapolated from the colorectal cancer setting, but disease biology differs and outcomes are inferior. The role of chemotherapy in the treatment of appendiceal cancer remains poorly defined. There is an urgent need to develop novel tailored treatment strategies in the perioperative and unresectable setting. This review aims to evaluate the literature for patients who received intraperitoneal and systemic chemotherapy for appendiceal cancers.

Enteral nutrition provides favorable postoperative outcomes for patients with pseudomyxoma peritonei: a retrospective study

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare malignancy, and many uncertainties regarding its treatment and prognosis still remain. The main treatment for PMP is cytoreductive surgery (CRS) combined with heated intraperitoneal chemotherapy (HIPEC), which can lead to intra-abdominal trauma and systemic reactions. Enteral nutrition (EN) is an important and beneficial perioperative option for major complicated abdominal surgery compared with total parenteral nutrition (TPN). However, the role of EN in PMP after surgery is still unknown. The purpose of this study was to analyze the effects of EN on postoperative outcomes in PMP patients.

METHODS

The perioperative clinical data of PMP patients from Xiangya Hospital of Central South University who accepted CRS plus HIPEC from January 2011 to December 2018 were collected and analyzed. The effects of EN on the nutritional status, postoperative complications, and hospital stay time of patients with PMP were studied. We further analyzed the risk factors affecting hospital stay and complications in PMP patients after surgery.

RESULTS

A total of 51 PMP patients accepted CRS and were enrolled in this study, including 25 cases in the EN group and 26 patients in the TPN group. The baseline demographic characteristics and preoperative nutritional status were not significantly different between the two groups. The postoperative absolute lymphocyte count (P<0.001), hemoglobin (P=0.016), and albumin (P<0.001) levels of the EN group were higher than those of the TPN group, but the postoperative hospital stay time (P=0.008) and the complication rate (P=0.03) in the EN group were less than those in the TPN group. Logistic regression analysis showed that age (P=0.031), American Society of Anesthesiologists (ASA) score (P=0.008), and EN (P=0.024) were independent risk factors for postoperative hospital stay in PMP patients. ASA score (P=0.006), number of prior operations (P=0.021), and EN (P=0.035) were independent risk factors for postoperative complications in PMP patients.

CONCLUSIONS

EN support results in better outcomes and is an independent protective factor for the postoperative hospital stay time and complications of PMP patients.

Novel Perspectives in Pseudomyxoma Peritonei Treatment

Simple Summary

Pseudomyxoma Peritonei (PMP) represents a rare entity which greatly benefits from Cytoreductive Surgery (CRS) associated with Hyperthermic Intraperitoneal Chemotherapy (HIPEC). In fact, CRS-HIPEC represents the treatment with potential chances of cure and long-term disease control of patients affected by PMP. This therapeutic strategy should be performed in referral centers, where a consolidated know-how of this locoregional treatment and a multidisciplinary approach are available. CRS-HIPEC provides excellent results for PMP patients in terms of postoperative outcome, overall and disease-free survival, and quality of life. However, in patients with an extensive or recurrent disease, few therapeutic opportunities are available. This review is focused on the most recent clinical evidence and provides a better understanding of the molecular prognostic factors and potential therapeutic targets in this rare malignancy.

Abstract

Pseudomyxoma Peritonei (PMP) is an anatomo-clinical condition characterized by the implantation of neoplastic cells on peritoneal surfaces with the production of a large amount of mucin. The rarity of the disease precludes the evaluation of treatment strategies within randomized controlled trials. Cytoreductive Surgery (CRS) combined with Hyperthermic Intraperitoneal Chemotherapy (HIPEC) has proven to be the only therapeutic option with potential chances of cure and long-term disease control. The present review discusses the epidemiology, pathogenesis, clinical presentation and treatment of PMP, focusing on the molecular factors involved in tumor progression and mucin production that could be used, in the upcoming future, to improve patient selection for surgery and to expand the therapeutic armamentarium.

Complete pathologic response after two-stage cytoreductive surgery with HIPEC for bulky pseudomyxoma peritonei: proof of concept

Introduction: Pseudomyxoma peritonei (PMP) is a rare disease characterized by the progressive accumulation of mucinous ascites and peritoneal implants. The optimal treatment for PMP includes the association of complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). For patients with a large burdensome disease, the completeness of cytoreduction sometimes requires maximal effort surgery. The aim of this article is to provide proof of concept for two stage cytoreductive surgery (CRS) in this category of patients.Methods and materials: A two stage CRS and HIPEC with oxaliplatin was proposed for patients with bulky PMP including important involvement of the serosal surfaces of the bowel or colon who had an impaired nutritional status. The residual disease at the end of the first stage was less than 5 mm of thickness on several implants. Clinical, surgical and histopathological variables were analyzed.Results: All eight patients completed the two-stage strategy. Mortality was nil. One Clavien Dindo grade 3 event occurred in each stage. After a median follow up of 29.5 months, all patients were alive and free of recurrence. All of the patients had histopathological complete response on the specimens obtained from the residual sites during the second stage surgery.Conclusions: Two-stage surgical strategy is feasible for bulky PMP patients and it is associated with little high-grade morbidity and enhanced visceral sparing.

Clinicopathological Characteristics and Prognostic Prediction in Pseudomyxoma Peritonei Originating From Mucinous Ovarian Cancer

OBJECTIVE

To describe the clinicopathological characteristics of mucinous ovarian cancer (MOC)-derived pseudomyxoma peritonei (PMP) and identify prognostic factors for survival.

METHODS

Medical records from patients with MOC-derived PMP who attended the Aerospace Center Hospital, Beijing, China between January 2009, and December 2019 were retrospectively reviewed. Survival analysis was performed with the Kaplan-Meier method, the log-rank test, and a Cox proportional hazards model.

RESULTS

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for PMP originating from MOC were performed on 22 patients, who had a median age of 52 years at the time of surgery. At the last follow-up in June 2020, 9 (41%) patients were still alive. Median OS was 12 months (range, 1 to 102 months), and the 2-, 3-, and 5-year survival rates were 23, 9, and 5%, respectively.

CONCLUSION

Histopathologic subtype and PCI may be applied as predictors of prognosis in patients with MOC-derived PMP. Patients with high-grade disease could benefit from completeness of cytoreduction (CCR) 0/1.

The Prognostic Impact of Pathology on Patients With Pseudomyxoma Peritonei Undergoing Debulking Surgery: A Systematic Review and Meta-Analysis of Retrospective Studies

Background: Pseudomyxoma peritonei (PMP) is a rare clinical condition with fatal outcomes, which is characterized by the progressive accumulation of mucinous ascites and peritoneal implants. Some studies have reported the effect of PMP biology on patient outcome. The objective of this study was to analyze published articles focusing on the impact of pathology on the prognosis of PMP patients undergoing debulking.

Methods: Data from all studies regarding the prognosis of patients, with different pathologies, who underwent debulking surgery were analyzed. We searched PubMed, the Wiley Online Library, Ovid, and the Cochrane Library (through January 2020). Studies were confined to those articles written in English. Five studies were identified, and the differences in 5-year survival rates were analyzed according to the Kaplan–Meier survival curves. The hazard ratios (HRs) of the 5-year survival rates were calculated.

Results: The mean and median 5-year survival rates of all patients were 39 and 40%, respectively. The median overall survival was 49.3 months. The mean 5-year survival rates of low-grade PMP was 45.2%. The five studies had sufficient data to calculate HRs from the 5-year survival rates data, and three had HRs lower than 1. The total HRs was 0.54, with a 95% CI between 0.33 and 0.89 (P = 0.01).

Conclusions: Among PMP patients receiving debulking surgery who are not able to undergo complete cytoreductive surgery, low-grade biological PMP had a better prognosis than high-grade PMP.

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.

Surgical management for peritoneal carcinomatosis of appendiceal origin with a high-tumor burden

PURPOSE

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) is the active treatment for peritoneal carcinomatosis of appendiceal origin. However, surgical management is sometimes difficult in patients with a high-tumor burden.

METHODS

A high-tumor burden was defined as a peritoneal cancer index (PCI) ≥ 28. Among 49 patients receiving CRS + HIPEC, 29 had a PCI ≥ 28.

RESULTS

Complete cytoreduction (CC-0/1) was achieved in 20 of the 29 patients with a PCI ≥ 28 and in all 20 patients with a PCI < 28. Among the patients achieving CC-0/1, gastrectomy or total colectomy was performed more frequently, the hospital stay was longer and postoperative complications were more frequent in those with a PCI ≥ 28 than in those with a PCI < 28. If CC-0/1 was achieved, the overall survival was comparable between patients with a PCI ≥ 28 and a PCI < 28. However, the recurrence-free survival was significantly worse for patients with a PCI ≥ 28 than for those with a PCI < 28 (5-year survival: 73.7% vs. 5.9%). Patients with recurrence who underwent repeat CRS showed a better overall survival than those without repeat CRS. Among patients with a PCI ≥ 28, a performance status (PS) of 2/3 was a significant prognostic factor (hazard ratio = 5.132).

CONCLUSIONS

In patients with a high-tumor burden undergoing CRS + HIPEC, postoperative complications were more frequent, and the recurrence rate was higher than in those without a high-tumor burden. Repeat CRS improved the survival of patients with recurrence. The PS was a key indicator when selecting patients suitable for aggressive resection.

Long-Term Outcomes after Surgery for Appendiceal Mucinous Tumours

BACKGROUND

Appendiceal mucinous tumour (AMT) is a very uncommon disease. We aimed to evaluate preoperative and postoperative characteristics as well as long-term outcomes of patients with appendiceal mucinous adenomas and peritoneal pseudomyxoma (PMP).

METHODS

A consecutive cohort of patients diagnosed with AMT were included in the study. Tumour recurrence and the development of PMP was diagnosed based on the patients' complaints, physical examination, imaging studies, and biopsy results. The calculation of survival rates was performed using the Kaplan-Meier method.

RESULTS

Between January 2003 and February 2013, 25 patients had AMT. 15 patients underwent appendectomy only (60%), 5 patients (20%) right hemicolectomy, 4 patients (16%) cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC), and 1 patient (4%) appendectomy with caecal resection. Another 2 patients underwent CRS and HIPEC 4 days and 3 years, respectively, following initial appendectomy. In the histopathologic examination, adenoma was diagnosed in 12 patients (48%); among these, low-grade PMP was found in 1 patient (4%). Low-grade appendiceal mucinous adenocarcinoma (AMCa) was diagnosed in 11 patients (44%); among these, low-grade PMP was found in seven cases (28%) and high-grade AMCa was diagnosed in 2 patients (8%). 2 of 8 PMP patients did not undergo CRS ± HIPEC because of comorbidities. The 5-year overall survival was 100% for the adenomas and 62% for PMP patients.

CONCLUSION

AMT is a very rare entity with a considerably good outcome even in disseminated disease. CRS and HIPEC is a gold standard treatment for PMP with excellent prognosis. However, our results could still be improved in the future.

Palliative Surgery for Pseudomyxoma Peritonei

Introduction:

Pseudomyxoma peritonei is a rare disease causing peritoneal carcinomatosis. In patients with extensive carcinomatosis, curative treatment is unachievable. Palliative debulking therapy is the only treatment in relieving symptoms. We report our results from palliative debulking surgery at a national pseudomyxoma peritonei center in Denmark.

Methods:

From January 2007 to October 2012, we performed 27 palliative operations for pseudomyxoma peritonei with debulking at our institution. All patients were evaluated and found eligible for palliative treatment only. Patients were prospectively registered, while perioperative data were collected retrospectively from patient records.

Results:

The majority of patients ( n = 25) received an omentectomy (93%) as the primary procedure. In total, 17 (63%) received additional surgery. Median operative time was 88 min (range: 33–160 min). Median stay at the recovery ward was 6 h (2–288 h). Median hospital stay was 8 days (4–105 days). In all, 23 (85%) patients had no in-hospital complications, whereas 4 patients experienced complications (15%). Two of the complications were mild (Clavien-Dindo grade II), and two experienced severe complications (grade III and IV). Thirty-day mortality was 0%. Median survival was 3.0 years (0.2–6.2 years).

Conclusion:

Palliative debulking is a safe procedure with an acceptable morbidity and mortality offering immediate disease control.

Drug Sensitivity Testing in Cytoreductive Surgery and Intraperitoneal Chemotherapy of Pseudomyxoma Peritonei

Background

Cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) is an established therapy for pseudomyxoma peritonei (PMP). However, the role of IPC is unclear. By ex vivo assessment of PMP tumor cell sensitivity to cytotoxic drugs, we investigated the basis for IPC drug selection and the role of IPC in the management of PMP.

Methods

Tumor cells were prepared by collagenase digestion of tumor tissue from 133 PMP patients planned for CRS and IPC. Tumor cell sensitivity to oxaliplatin, 5FU, mitomycin C, doxorubicin, irinotecan, and cisplatin was assessed in a 72-h cell-viability assay. Drug sensitivity was correlated to progression-free survival (PFS) and overall survival (OS).

Results

Samples from 92 patients were analyzed successfully. Drug sensitivity varied considerably between samples. Peritoneal mucinous carcinomatosis (PMCA), compared with PMCA intermediate or disseminated peritoneal adenomucinosis, was slightly more resistant to platinum and 5FU and tumor cells from patients previously treated with chemotherapy were generally less sensitive than those from untreated patients. Multivariate analysis showed patient performance status and completeness of CRS to be prognostic for OS. Among patients with complete CRS (n = 61), PFS tended to be associated with sensitivity to mitomycin C and cisplatin (p ≈ 0.06). At the highest drug concentration tested, the hazard ratio for disease relapse increased stepwise with drug resistance for all drugs.

Conclusions

Ex vivo assessment of drug sensitivity in PMP provides prognostic information. The results suggest a role for IPC as therapeutic adjunct to CRS and for individualization of IPC by pretreatment assessment of drug sensitivity.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-015-4675-0) contains supplementary material, which is available to authorized users.

Comparison of serial debulking and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy in pseudomyxoma peritonei of appendiceal origin

PURPOSE

Patients with pseudomyxoma peritonei (PMP) benefit from cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Reports on this modality usually have included only patients with successful HIPEC treatment, which can potentially cause biased results. We report the survival of a PMP population treated by CRS and HIPEC, including patients who were not eligible for HIPEC.

METHODS

The outcome of the whole population of 87 patients with PMP treated by CRS and HIPEC in Helsinki University Central Hospital between 2008 and 2011 was evaluated. The results of treatment were compared with 33 patients treated by serial debulking in our unit between 1984 and 2008.

RESULTS

Of the 87 patients in the HIPEC-era group, 56 received HIPEC, 12 were treated non-radically in an attempt at HIPEC, 9 were debulked and 10 were referred back or transferred to palliative care without surgery. The 5-year overall survival for the debulking-era group and the HIPEC-era group were 67 and 69 %, respectively. The number of patients with no evidence of disease was higher in the HIPEC-era group (47/87) than that in the debulking-era group (8/33) at the end of the follow-up. Overall survival for patients who underwent successful CRS and HIPEC at 2 and 5 years was 95 and 93 %, respectively.

CONCLUSIONS

The improved survival from using the CRS and HIPEC was not apparent after 5-year follow-up, when the whole patient population was included in the analysis. Even so, patients successfully treated by CRS and HIPEC manage well.

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.

Cytoreductive surgery plus perioperative intraperitoneal chemotherapy in pseudomyxoma peritonei: aspects of the learning curve

BACKGROUND

Cytoreductive surgery (CRS) plus perioperative intraperitoneal chemotherapy is a highly invasive treatment of peritoneal metastasis and requires many surgical procedures before mastering. The aim of this study was to estimate how many procedures are needed before stabilization can be seen in surgical outcome (R1 surgery, adverse events and bleeding) in patients with pseudomyxoma peritonei (PMP).

PATIENTS AND METHODS

All 128 patients with PMP who were treated with CRS alone or CRS plus perioperative intraperitoneal chemotherapy between 2003 and 2008 at the Uppsala University Hospital, Uppsala, Sweden, were included. The learning curve was calculated using the partial least square (PLS) and cumulative sum control chart (CUSUM) graph. Two groups were formed based on the results of the learning curve. The learning curve plateau was considered the same as the stabilization in the CUSUM graph. Group I consisted of patients included during the learning period (n = 73) and Group II of patients treated after the learning period ended (n = 55). Comparisons between the groups were made on surgical outcome, survival and adverse events.

RESULTS

Stabilization was seen after 220 ± 10 procedures. A higher occurrence of R1 surgery was seen in Group II (80%) compared to Group I (48%; P = 0.0002). Overall survival increased at four years after surgery in Group II compared to Group I (80% vs. 63%; P = 0.02).

CONCLUSION

CRS plus perioperative intraperitoneal chemotherapy is a highly demanding procedure that requires more than 200 procedures before optimisation in surgical outcome is seen.

Outcome of patients with aggressive pseudomyxoma peritonei treated by cytoreductive surgery and intraperitoneal chemotherapy

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare disease with an incidence rate of approximately 1 per million a year. During the past few years, there has been a survival benefit for these patients treated by complete cytoreduction and perioperative chemotherapy. Better survival rates were found in the adenomucinosis group than the carcinomatosis group. The purpose of our study was to analyze the outcome and the prognosis factors of only high-grade PMP.

METHODS

We selected 38 patients from a prospective database of 59 with high-grade PMP from appendiceal origin who were treated by cytoreduction surgery and HIPEC at the Hospital University Reina Sofia (Cordoba, Spain) between 1998 and July 2012. Clinical, surgical, analytical, radiological, and histological data were obtained prospectively. Survival curves were calculated using the Kaplan-Meier method, a univariate analysis was performed and the log rank-test was used to analyze the effects of several clinical and pathologic factors on overall survival (OS) and disease-free survival (DFS).

RESULTS

Median follow-up time was 32 months (range, 2-170). Median age at diagnosis was 57 years (range, 32-77). In 89.5 % of patients, optimal cytoreduction CC-0 (57.9 %) and CC-1 (31.6 %) was achieved. In the remaining 10.5 %, cytoreduction was classified as CC-2. The median PCI score was 21 (range, 4-38). Morbidity complications ≥ Grade 3 in the CTCAE v 3.0 classification was 18.4 %. One patient died 45 days postsurgery. Median OS at the end of follow-up was 36 months (range, 9-83); overall 5-year survival rate was 58.7 %. In the univariate analysis for OS, significant values were obtained for lymph-node involvement and suboptimal cytoreduction. The 5-year OS was 64.5 % when an optimal cytoreduction was achieved. Median DFS was 36 months (17-54); 3-year DFS rate was 49.1 %. Neoadjuvant therapy did not affect the survival of these patients; there was no difference in the 5-year OS (43 % vs. 75 %, p = 0.068).

CONCLUSIONS

In aggressive PMP, cytoreduction with peritonectomy procedure plus HIPEC is a safe procedure that suggests an improvement to the survival rates. Because optimal cytoreduction is a primary prognostic factor for survival rates, this procedure would have to be performed in an experienced center with a low morbidity. Neoadjuvant chemotherapy has not demonstrated benefits in these patients and further research will be required.