Secondary cytoreduction and perioperative intraperitoneal chemotherapy after initial debulking of pseudomyxoma peritonei: a study of timing and the impact of malignant dedifferentiation

Scalloping of the Liver and Spleen on Preoperative CT-Scan of Pseudomyxoma Peritonei Patients: Impact on Prediction of Resectability, Grade, Morbidity and Survival

Simple Summary

Liver and/or spleen scalloping is a common radiologic sign visible on preoperative computed tomography scans of pseudomyxoma peritonei patients. While several studies have reported a predictive value of this scalloping regarding resectability, histologic grade, postoperative morbidity risk and long-term oncologic outcomes, few data are available regarding splenic scalloping. The predictive value of hepatic and splenic scalloping characteristics (measures and density) was assessed. It appeared that scalloping was associated for a more extensive disease, requiring more complex cytoreduction, but it was not associated with resectability, histologic grade, postoperative complications, or survival.

Abstract

Pseudomyxoma peritonei (PMP) is ideally treated by cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC), leading to significant morbidity. Beyond the histologic grade, the prognosis lies in the completeness of cytoreduction (CC-score of 0/1 vs. 2/3) and the severe complication rate. The mucinous nature of the peritoneal implants sometimes induces liver and/or spleen scalloping on imaging. The predictive value of scalloping was assessed regarding resectability, grade, survival and severe morbidity. This monocentric, retrospective analysis compared CC-0/1 with CC-2/3 groups regarding liver and spleen scalloping parameters, assessed on pre-operative computed tomography (CT) scan, reviewed for the study. In addition, prognostic factors of severe complications and recurrence-free and overall survivals were explored in the CC-0/1 population. Overall, 129 patients were included (109 CC-0/1, 20 CC-2/3), with 58 (45%) exhibiting scalloping. All patients with splenic scalloping also had a liver one. Scalloping was more frequent (75% vs. 39%), with greater median maximal depth (21 vs. 11 mm) and higher PCI (32 vs. 14) in the CC-2/3 population, but was not predictive of either grade or survival. In CC-0/1 patients, survivals and postoperative complications were not affected by scalloping parameters. Scalloping appeared as a marker of advanced PMP, but was not predictive of grade, severe complications, or long-term outcomes.

Outcomes and prognostic factors of cytoreductive surgery and perioperative intraperitoneal chemotherapy in high-volume peritoneal carcinomatosis

BACKGROUND AND OBJECTIVES

The management of patients with extensive appendiceal mucinous neoplasms and mesothelioma is controversial. Our aims were to analyze overall survival (OS), disease-free survival (DFS) and independent prognostic factors associated with high peritoneal cancer index (PCI) status in patients who underwent cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy (PIC).

METHODS

A prospectively-maintained database for patients with appendiceal neoplasms and mesothelioma undergoing CRS/PIC from year 1996 to 2018 was retrospectively analyzed. Patients who achieved complete cytoreduction were stratified into limited (PCI < 30) and extensive (PCI ≥ 30) disease groups.

RESULTS

260 female and 235 male patients were identified. The 5-year survival for low-grade appendiceal mucinous neoplasms (LAMN) was significantly higher in the low PCI group (96.2% vs. 63.5%, p < 0.001). There was no difference in the OS across both groups in high-grade appendiceal mucinous neoplasms (HAMN) (63 vs. 69 months; p = 0.942) and mesothelioma (72 vs. 42 months; p = 0.058). Overall mortality was 2%. Grade III/IV complications were significantly higher in extensive disease (68% vs. 36.6%, p < 0.001). On multivariate analysis, use of EPIC and blood transfusion (>8 units) were independent positive and negative prognostic factors, respectively, associated with OS. Meanwhile, use of EPIC conferred benefit in DFS while increased blood transfusion (>8 units) and elevated preoperative CA125 were predictive of a poor DFS.

CONCLUSION

Long-term survivals following CRS/PIC are achievable with acceptable mortality and higher morbidity rates in extensive appendiceal mucinous neoplasms and mesothelioma. High PCI status does not preclude treatment with CRS/PIC.

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.

Evidence-Based Strategies for the Treatment of Peritoneal Malignancies during Health Care Resource Restriction: The COVID-19 Pandemic

Background: The COVID-19 pandemic has put enormous pressure on hospital resources, and has affected all aspects of patient care. As operative volumes decrease, cancer surgeries must be triaged and prioritized with careful thought and attention to ensure maximal benefit for the maximum number of patients. Peritoneal malignancies present a unique challenge, as surgical management can be resource intensive, but patients have limited non-surgical treatment options. This review summarizes current data on outcomes and resource utilization to help inform decision-making and case prioritization in times of constrained health care resources. Methods: A rapid literature review was performed, examining surgical and non-surgical outcomes data for peritoneal malignancies. Narrative data synthesis was cross-referenced with relevant societal guidelines. Peritoneal malignancy surgeons and medical oncologists reviewed recommendations to establish a national perspective on case triage and mitigating treatment strategies. Results and Conclusions: Triage of peritoneal malignancies during this time of restricted health care resource is nuanced and requires multidisciplinary discussion with consideration of individual patient factors. Prioritization should be given to patients where delay may compromise resectability of disease, and where alternative treatment options are lacking. Mitigating strategies such as systemic chemotherapy and/or surgical deferral may be utilized with close surveillance for disease stability or progression, which may affect surgical urgency. Unique hospital capacity, and ability to manage the complex post-operative course for these patients must also be considered to ensure patient and system needs are aligned.

Factors influencing long-term survival after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei originating from appendiceal neoplasms

Background

Pseudomyxoma peritonei (PMP) is a rare disease, most commonly of appendiceal origin. Treatment consists of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS–HIPEC). The aim of this study was to identify prognostic factors for recurrence and survival.

Methods

This was an observational study using a prospectively designed database containing consecutive patients with PMP originating from the appendix, undergoing CRS–HIPEC at a tertiary referral centre between 1996 and 2015. Histopathological slides were reassessed. Cox regression was used for multivariable analyses.

Results

Of 225 patients identified, 36 (16·0 per cent) were diagnosed with acellular mucin, 149 (66·2 per cent) had disseminated peritoneal adenomucinosis (DPAM) and 40 (17·8 per cent) had peritoneal mucinous carcinomatosis (PMCA). The 5‐year overall survival (OS) rates were 93, 69·8 and 55 per cent respectively. Recurrence was observed in 120 patients (53·3 per cent), 39 of whom (17·3 per cent) were treated with a second CRS–HIPEC procedure. Factors independently associated with poor disease‐free survival were six or seven affected regions (hazard ratio (HR) 6·01, 95 per cent c.i. 2·04 to 17·73), incomplete cytoreduction (R2a resection: HR 1·67, 1·05 to 2·65; R2b resection: HR 2·00, 1·07 to 3·73), and more than threefold raised carcinoembryonic antigen (CEA) and/or carbohydrate antigen (CA) 19‐9 level (HR 2·31, 1·30 to 4·11). Factors independently associated with poorer OS were male sex (HR 1·74, 1·09 to 2·77), incomplete cytoreduction (R2a resection: HR 1·87, 1·14 to 3·08; R2b resection: HR 2·28, 1·19 to 4·34), and more than threefold raised CEA and/or CA19‐9 level (HR 2·89, 1·36 to 6·16).

Conclusion

CEA and CA19‐9 levels raised more than threefold above the upper limit identify patients with PMP of appendiceal origin and poorer survival.

Peritoneal Metastases from Appendiceal Cancer

The early symptoms of appendiceal cancer may mimic the clinical picture of appendicitis. Most patients are diagnosed incidentally during surgical exploration or late when peritoneal or systemic dissemination has already occurred, as colonoscopy rarely will diagnose an appendiceal cancer. Systemic/extraperitoneal metastases are distinctly unusual for appendiceal mucinous lesions.

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.

Transformation of low-grade mucinous neoplasm of the appendix with pseudomyxoma peritonei to high-grade sarcomatoid carcinoma

A 66-year-old man initially underwent appendectomy and cytoreductive surgery for a low-grade appendiceal mucinous neoplasm with pseudomyxoma peritonei. One and a half years later, multiple disseminated lesions developed in rectus abdominis muscle and peritoneal cavity. Biopsy showed histopathological transformation to sarcomatoid carcinoma. This case illustrates that evolution of low-grade pseudomyxoma peritonei to high-grade carcinoma truly develops in some patients. The development of this dedifferentiation appears associated with aggressive behavior and poor clinical outcome.

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.

Cure for peritoneal metastases? An evidence-based review

There is now a considerable body of published evidence supporting the use of a multimodal approach consisting of cytoreductive surgery (CS) and heated intraperitoneal chemotherapy (HIPEC) in the treatment of peritoneal metastases (PM) arising from selected gastrointestinal tract malignancies. In the absence of systemic metastases, it is thought that disease confined to the peritoneum may be eradicated through optimum cytoreduction. This review critically evaluates the current body of published evidence for the use of CS/HIPEC in the treatment of advanced colorectal, appendiceal and gastric cancer. Although its role remains less defined in patients with gastric PM, current evidence provides a compelling argument for its use in PM of colorectal and appendiceal origin. With a low mortality and acceptable morbidity rate, CS/HIPEC may offer hope of long-term survival and cure in a defined group of patients with this disease.

Iterative cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for recurrent peritoneal metastases

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) achieves disease control within the peritoneum but recurrences occur. This study examines the outcomes of iterative CRS (iCRS) HIPEC for treatment of recurrent peritoneal metastases.

METHODS

Patients who underwent iCRS in a single tertiary referral center were identified from a prospective database. Safety analysis was performed and clinicopathological variables were analyzed to assess factors predictive of major morbidity and survival.

RESULTS

The demographics of patients who underwent primary cytoreductive surgery (pCRS) (n = 466) and iCRS (n = 79) were balanced between groups. pCRS was shown to require more blood transfusion (P = 0.019) and albumin use (P = 0.013). The mortality and major complication rates were comparable (1.2% vs. 0%; P = 0.600, and 42% vs. 41%; P = 0.806). Residual pneumothorax occurred more frequently after pCRS (12% vs. 4%; P = 0.030). Factors associated with major complications after iCRS include use of HIPEC (P = 0.042) and length of hospital stay (P = 0.024). The overall median survival was 48 months and 5-year survival was 34%. By cancer type, the 3-year survival was 0%, 74%, 80%, and 72% for colorectal, appendiceal pseudomyxoma, peritoneal mesothelioma, and appendix cancer, respectively. Independent predictors of survival include age (P = 0.049), interval between pCRS and iCRS (P = 0.008), small bowel resection (P < 0.001), and use of HIPEC (P = 0.005).

CONCLUSION

Iterative CRS achieved further peritoneal disease control without adverse effects on morbidity. Patients with appendiceal tumors and peritoneal mesothelioma appear to benefit most after iCRS. Intraoperative HIPEC remains important in the repetoire of managing these patients.

Early recurrence of pseudomyxoma peritonei following treatment failure of cytoreductive surgery and perioperative intraperitoneal chemotherapy is indicative of a poor survival outcome

BACKGROUND

The aim of this study was to identify predictors of early recurrence to optimize outcomes.

METHODS

A comparison of clinicopathological factors between patients who developed early recurrence (≤12 months) and late recurrence (>12 months) was performed to identify predictors of treatment failure through univariate and multivariate analyses. Survival parameters were estimated using the Kaplan-Meier method.

RESULTS

A total of 113 patients with a median PCI of 24 (range, 2-39) underwent cytoreductive surgery. The median progression-free and overall survival was 48 and 104 months, respectively. Multivariate analysis identified prior operations >1, ≥10 units of fresh frozen plasma (FFP) transfusion, incomplete cytoreduction and not undergoing definitive cytoreductive surgery within 12 months of diagnosis as predictors for disease recurrence. Twenty of 41 patients (49%) developed early recurrence. The median overall survival of patients who developed early recurrence was 38 months and in patients who did not develop early recurrence was 97 months (P = 0.002). Subgroup analysis of patients with recurrence identified the male gender (P = 0.028), elevated CA 125 (P = 0.037), having elevated carcinoembryonic antigen (CEA), CA 125 and CA 19-9 (P = 0.029), peritoneal cancer index >25 (P = 0.020), incomplete cytoreduction (P = 0.020), >6 units of blood transfusion (P = 0.020) and >10 units of FFP transfusion (P = 0.009) as factors associated with early recurrence.

CONCLUSION

Early recurrence of pseudomyxoma peritonei occurs despite achieving high rates of oncologically optimal cytoreduction. The clinicopathologic factors associated with early recurrence identified in this study may inform us about patients at greatest risk of treatment failure during the post cytoreduction follow-up.