Recurrence of pseudomyxoma peritonei after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Repeat cytoreductive surgery with HIPEC for colorectal peritoneal metastases: a systematic review

BACKGROUND

Colorectal peritoneal metastases (CRPM) are present in 10-20% of patients at the time of their initial cancer diagnosis, and affects over 20% of those who develop colorectal cancer recurrence. Cytoreductive surgery (CRS) with HIPEC is firmly established as the optimal surgical treatment, but there is very little known about the benefit of repeat or iterative CRS. The aim of this review is to provide a systematic evaluation of the perioperative complications, survival outcomes and quality of life in patients undergoing repeat CRS with HIPEC for CRPM.

METHODS

A systematic review of PubMed, Ovid MEDLINE, EMBASE, Scopus and Cochrane databases was performed to identify all studies that reported outcomes for repeat CRS with or without HIPEC for CRPM.

RESULTS

Four hundred and ninety-three manuscripts were screened, and 15 retrospective studies were suitable for inclusion. Sample sizes ranged from 2 to 30 participants and comprised a total of 229 patients. HIPEC was used in all studies, but exact rates were not consistently stated. Perioperative morbidity was reported in four studies, between 16.7% and 37.5%. Nine studies reported mortality rate which was consistently 0%. The median overall survival after repeat CRS ranged from 20 to 62.6 months. No studies provided quality of life metrics.

CONCLUSION

Repeat CRS for CRPM has perioperative morbidity and mortality rates comparable to initial CRS, and offers a potential survival benefit in selected patients. There is however limited high-quality data in the literature.

Ovarian Causes of Pseudomyxoma Peritonei (PMP)-A Literature Review

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare, progressive, slowly growing, inadequately understood neoplasm with a 5-year progression-free survival rate of as low as 48%. It is characterized by varying degrees of malignancy and the production of mucinous and gelatinous structures. Typically, the development of pseudomyxoma peritonei is associated with the rupture of appendiceal mucinous tumors and other gastrointestinal or ovarian mucinous tumors. The goal of our literature review was to identify various aspects that characterize the ovarian causes of pseudomyxoma peritonei.

MATERIALS AND METHODS

The authors performed an extensive literature search between 1 February 2024 and 2 March 2024 on the following databases: Pubmed, Scopus, Oxford Journals, and Reaxys, and the findings were summarized into seven main clinical and paraclinical situations.

RESULTS

According to our research, the main instances in which pseudomyxoma peritonei can be triggered by an ovarian cause are the following: (1) mucinous cystadenoma; (2) mucinous ovarian cancer; (3) colon cancer with ovarian metastasis; (4) malignant transformation of an ovarian primary mature cystic teratoma; (5) appendiceal mucocele with peritoneal dissemination mimicking an ovarian tumor with peritoneal carcinomatosis; (6) mucinous borderline tumor developing inside an ovarian teratoma; and (7) the association between a mucinous bilateral ovarian cancer and a colonic tumor.

CONCLUSIONS

In our study, we aimed to provide a comprehensive overview of the ovarian causes of pseudomyxoma peritonei, including its epidemiology, imagery characteristics, symptoms, current treatment, and promising future therapies, in the hopes of finding feasible solutions, as a lack of understanding of this mucus-secreting malignant disease increases the risk of delayed diagnosis or uncontrolled deterioration.

Progress in Biological Research and Treatment of Pseudomyxoma Peritonei

Pseudomyxoma peritonei (PMP) is a rare disease characterized by extensive peritoneal implantation and mass secretion of mucus after primary mucinous tumors of the appendix or other organ ruptures. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is currently the preferred treatment, with excellent efficacy and safety, and is associated with breakthrough progress in long-term disease control and prolonged survival. However, the high recurrence rate of PMP is the key challenge in its treatment, which limits the clinical application of multiple rounds of CRS-HIPEC and does not benefit from conventional systemic chemotherapy. Therefore, the development of alternative therapies for patients with refractory or relapsing PMP is critical. The literature related to PMP research progress and treatment was searched in the Web of Science, PubMed, and Google Scholar databases, and a literature review was conducted. The overview of the biological research, treatment status, potential therapeutic strategies, current research limitations, and future directions associated with PMP are presented, focuses on CRS-HIPEC therapy and alternative or combination therapy strategies, and emphasizes the clinical transformation prospects of potential therapeutic strategies such as mucolytic agents and targeted therapy. It provides a theoretical reference for the treatment of PMP and the main directions for future research.

Health related quality of life is excellent and sustained at two decades after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in survivors of pseudomyxoma peritonei of appendiceal origin

INTRODUCTION

Optimal management of pseudomyxoma peritonei (PMP) is by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), which can achieve 20-year disease-free, and overall survival. There is limited information on the health-related quality of life (HRQOL) of PMP survivors beyond five years. We report longitudinal HRQOL in patients with PMP of appendiceal origin up to 17-years after their CRS and HIPEC in 2003-2004.

METHODS

Patients had HRQOL assessed with EORTC QLQ-C30 questionnaires pre-operatively, and at 1-, 10- and 17-years post-operatively. Comparisons in global health-related QOL (global-HRQOL) measures were made with (1) an age- and sex-matched normal European population, (2) between patients who underwent complete cytoreduction (CRS CC0/1) versus maximal tumor debulking (MTD), and (3) between those with and without peritoneal recurrence.

RESULTS

Forty-six patients underwent CRS & HIPEC for appendiceal PMP. One patient withdrew from the study. Of the 45 patients, 23 patients were alive at ten and 15 patients at 17-years post-operatively. 21/23 (91%) and 14/15 patients (93%) completed questionnaires respectively. Pre-operatively, patients had significantly lower global-HRQOL compared with the reference population. Over follow-up, patients experienced improvements in their global-HRQOL. By post-operative year-10 and -17, there was no difference between the global-HRQOL of patients and reference population. As expected, patients with CC0/1 and without peritoneal tumor recurrence had better global-HRQOL at ten- and 17-years post-operatively compared with those with MTD or recurrence.

CONCLUSIONS

Optimal CRS and HIPEC is an effective treatment for appendiceal PMP that can achieve long-term survival. HRQOL is excellent and maintained, in those who have CC0/1 without recurrence.

Patterns of Recurrence in Appendix Cancer After Complete Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

It is thought that low-grade (LG) appendiceal cancer (AC) demonstrates predominantly intraperitoneal recurrence (IPR) after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), whereas high-grade (HG) tumors progress both intra- and extraperitoneally (EPR). However, evidence supporting this conception is lacking; therefore, we assessed recurrence in various AC histologies.

METHODS

A retrospective, cohort study was conducted by using a single-center database (1998-2022). Recurrence patterns (IPR, EPR, combined) were identified for LG, HG, high-grade with signet ring cells (SRC), and goblet cell carcinoma (GCC).

RESULTS

We included 432 complete (CC-0/1) CRS/HIPECs: 200 LG, 114 HG, 72 SRC, and 46 GCC. Median follow-up was 78 (95% confidence interval [CI] 70-86) months. Overall, 34% (n = 148) of patients recurred. IPR was the most common (LG 16%, HG 27%, SRC 36%, GCC 26%) with median time to recurrence (MTR) of 21 (IQR: 12-40) months. EPR (liver, lung, pleura, lymph nodes, or bones) occurred in LG 3%, HG 9%, SRC 22%, and GCC 7%. MTR was 11 (IQR: 4-16) months. Combined pattern occurred in LG 0%, HG 8%, SRC 7%, and GCC 0%. MTR was 13 (IQR: 7-18) months. Iterative surgery was performed in 53% IPR, 18% EPR, and 51% combined. Median post-recurrence survival was longer after IPR compared with EPR and combined recurrence: 36 (95% CI 25-47) versus 13 (95% CI 7-19) and 18 (95% CI 6-30) months (p < 0.01).

CONCLUSIONS

After complete CRS/HIPEC, IPR was the predominant pattern in all AC histologies and occurred later. Post-recurrence survival after IPR was longer. Knowing AC recurrence patterns can help to understand its biology and plan follow-up and post-relapse management.

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

[Surgical treatment for recurrent intra-abdominal mucinous neoplasms]

BACKGROUND

The gold standard in the treatment of mucinous intra-abdominal neoplasms is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Despite complete cytoreduction up to 45% of patients develop recurrences.

METHOD

A search and analysis of the current literature were carried out.

RESULTS

There is still controversy regarding the best treatment strategy for patients with recurrent pseudomyxoma peritonei (PMP) after CRS and HIPEC. The clinical management of these patients depends on many factors, such as the site and volume of recurrence, histological subtype and symptoms. Treatment options range from repeated surgery with curative intent with or without HIPEC to watch and wait strategies. In selected patients redo surgery is feasible and safe with low morbidity and mortality. Iterative complete CRS can result in a median 5‑year overall survival of more than 80%. Debulking surgery leads to a prolonged survival and to symptom control fora period with of nearly 2 years.

CONCLUSION

Repeated complete cytoreduction of recurrent PMP can result in long-term survival. Tumor debulking surgery may be particularly beneficial for symptomatic patients.

Oral administration of bromelain and acetylcysteine in pseudomyxoma peritonei (PMP) caused by low-grade appendiceal mucinous neoplasm (LAMN): a case report

BACKGROUND

Pseudomyxoma Peritonei (PMP) is a severe neoplastic clinical syndrome characterised by secretion of mucin from tumors often originating in the appendix. The standard treatment includes cytoreductive surgery (CRS) combined with heated intraperitoneal chemotherapy (HIPEC). A new perspective in PMP treatment aims at the mucins themselves as a therapeutic target.

CASE PRESENTATION

Here we report the first case of PMP with peritoneal dissemination of mucinous implants caused by low-grade appendiceal mucinous neoplasm (LAMN) in a 58-year-old white male exclusively treated by appendectomy and oral administration of bromelain and acetylcysteine in the context of a medical self-experimentation (by co-author T.R.). Observation so far covers a period of 48 months including regular magnetic resonance imaging (MRI) with stable findings.

CONCLUSIONS

Oral administration of bromelain and acetylcysteine can be used in the treatment of PMP caused by LAMN without relevant clinical side effects.

Determining a minimum data set for reporting clinical and radiologic data for pseudomyxoma peritonei

Objectives

Pseudomyxoma peritonei (PMP) is a rare cancer currently affecting over 11,736 patients across Europe. Since PMP is so uncommon, collaboration between scientific centers is key to discovering the mechanisms behind the disease, efficient treatments, and targets pointing to a cure. To date, no consensus has been reached on the minimum data that should be collected during PMP research studies. This issue has become more important as biobanking becomes the norm. This paper begins the discussion around a minimum data set that should be collected by researchers through a review of available clinical trial reports in order to facilitate collaborative efforts within the PMP research community.

Content

A review of articles from PubMed, CenterWatch, ClinicalTrials.gov and MedRxiv was undertaken, and clinical trials reporting PMP results selected.

Summary

There is a core set of data that researchers report, including age and sex, overall survival, peritoneal cancer index (PCI) score, and completeness of cytoreduction, but after this, reports become variable.

Outlook

Since PMP is a rare disease, it is important that reports include as large of a number of standardised data points as possible. Our research indicates that there is still much ground to cover before this becomes a reality.

Significance of laparoscopic cytoreductive surgery for appendiceal pseudomyxoma peritonei with limited disease and low tumor burden

OBJECTIVE

To investigate the clinical value of laparoscopic cytoreductive surgery (CRS) in treating of appendiceal pseudomyxoma peritonei with limited disease and low tumor burden.

METHODS

The clinical data of patients with appendiceal pseudomyxoma peritonei treated by surgery with CRS at the Aerospace Center Hospital from January 2018 to December 2021 were retrospectively analyzed. The patients were divided into laparoscopic or open CRS groups according to the operation method. A propensity score-matched (PSM) analysis (1:1) was performed, the related clinical variables were compared between the two groups, and the effect on progression-free survival (PFS) was also analyzed.

RESULTS

One hundred and eight patients were included in this study. After PSM, 33 patients were selected from each group and the age and peritoneal cancer index were matched between the two groups. There were significant differences in operation time (P < 0.001), intraoperative bleeding (P < 0.001), intraoperative blood transfusion (P = 0.007), hospital stay (P < 0.001). The analysis of PFS showed that there was no significant difference between the two operation methods. After multivariate analysis, the pathologic subtype (P = 0.012) was identified as an independent prognostic factor for PFS.

CONCLUSION

The curative effect of laparoscopic CRS is like that of open operation, which can significantly shorten the operation time and hospital stay and reduce intraoperative bleeding and blood transfusion event. The laparoscopic CRS is safe and feasible in strictly selected patients. The pathologic subtype is an independent factor affecting the prognosis for PFS.

Relapse of Pseudomyxoma Peritonei After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Pattern of Failure, Clinical Management and Outcomes

INTRODUCTION

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) have dramatically improved pseudomyxoma peritonei (PMP) prognosis, but treatment failures are still a concern. We investigated the pattern of failure, treatment and outcomes of progressing disease.

METHODS

A prospective database of 374 PMP patients was reviewed, and 152 patients relapsing after complete CRS/HIPEC were identified. PMP was graded according to the Peritoneal Surface Oncology Group International (PSOGI) classification. Hematogenous metastases and non-regional lymph node involvement were considered as systemic metastases.

RESULTS

Median follow-up was 78.3 months (95% confidence interval [CI] 66.7-90.4). PMP relapse involved the peritoneum in 112 patients, pleural cavity in 8, both peritoneum and pleura in 8, systemic sites in 11, and both peritoneum and systemic sites in 13 patients. Systemic metastases involved the lung (n = 14), liver (n = 4), distant nodes (n = 3), bone (n = 2), and both lung and distant nodes (n = 1). Survival after diagnosis of PMP relapse was independently associated with curative versus palliative treatment (hazard ratio [HR] 0.52, 95% CI 0.36-0.75; p = 0.001) and PSOGI histology (HR 1.80, 95% CI 1.19-2.74; p = 0.005), but was not influenced by site of failure (p = 0.444). Ten-year overall survival was 77.5% for 62 patients who had curative-intent surgery for PMP relapse, compared with 83.0% for 192 patients who had no recurrences (p = 0.154) and 26.1% for 90 patients who underwent palliative treatments (p = 0.001).

CONCLUSIONS

Relapse after CRS/HIPEC most commonly involves the peritoneum, but pleural recurrences and systemic metastases occur in a small but clinically relevant number of patients. In selected patients, surgical resection of recurrent disease can result in long survival, irrespective of sites of failure.

Clinical epidemiology of peritoneal metastases in China: The construction of professional peritoneal metastases treatment centers based on the prevalence rate

OBJECTIVE

To understand the tumor burden of peritoneal metastases (PM) in China, and to guide the construction of professional PM treatment centers in China.

METHODS

Based on the cancer statistics by the National Cancer Center of China published in 2016, the prevalence of PM in 2020 was calculated according to the population statistics in China and the survival and mortality rates of various PM.

RESULTS

The prevalence rates of PM in China were as follows: gastric cancer PM 371.0/million, absolute number 523,937; colorectal cancer PM 47.1/million, absolute number 66,482; ovarian cancer PM 97.1/million, absolute number 137,083; pseudomyxoma peritonei 25.1/million, absolute number 35,425; malignant peritoneal mesothelioma 2.6/million, absolute number 3737; the above total was 766,664. According to the annual high-quality treatment volume of 365 cases in each professional PM treatment center, China needs to establish 1194 specialized PM treatment centers. At present, there are 1580 tertiary first-class hospitals in China. Therefore, for every 3 first-class tertiary hospitals in China there should be at least 2 PM treatment centers in full operation.

CONCLUSIONS

Considering the large number of PM patients in China and the relatively small number of professional PM treatment centers, more resources should be devoted to the promotion and construction of PM treatment centers.

Adjuvant chemotherapy for high-grade appendiceal cancer after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

INTRODUCTION

There are no available data on the efficacy of adjuvant chemotherapy (ACT) in stage IVA/B high-grade mucinous appendiceal cancer treated with CRS/HIPEC. We evaluated the association between ACT and survival in this cohort.

MATERIALS AND METHODS

A single-institution retrospective cohort study using a prospective database was conducted. Stage IVA/B high-grade mucinous appendiceal cancer patients who underwent CRS/HIPEC with CC-0/1 were included. Survival was compared between ACT and no chemotherapy (NoCT) patients. Subgroup analysis was performed with adjustment for confounding variables.

RESULTS

We identified 180 patients: 77 ACT and 103 NoCT. ACT regimens included 5-FU/capecitabine (13%), oxaliplatin-based (63%), and irinotecan-based (21%), combined with bevacizumab in 27% of cases. Median number of cycles was 9 (IQR: 6-12). Median overall survival (OS) did not significantly differ between ACT and NoCT (53 vs 75 months, p = 0.566). Multivariable Cox regression showed no OS benefit for ACT vs NoCT in patients with neoadjuvant chemotherapy (HR 1.14; 95%CI: 0.38-3.39) or without it (HR 1.33; 95%CI: 0.69-2.57), with signet ring cell (HR 0.89; 95%CI: 0.38-2.06) or other histologies (HR 1.11; 95%CI: 0.50-2.46), positive lymph nodes (HR 1.60; 95%CI: 0.74-3.49), or peritoneal cancer index ≥20 (HR 1.08; 95%CI: 0.55-2.11) after adjusting for other factors.

CONCLUSIONS

In our cohort, colon-type ACT was not associated with better OS in stage IVA/B mucinous appendiceal cancer after CRS/HIPEC, even after adjusting for confounders. This may be due to different tumor biology than colon cancer or small sample size. Prospective collaborative studies are needed.

[Current treatment recommendations for pseudomyxoma peritonei]

BACKGROUND

The term pseudomyxoma peritonei (PMP) describes a clinical syndrome characterized by the presence of gelatinous intraperitoneal accumulation of mucus. It mostly originates from a mucocele of the vermiform appendix. Affected patients are often asymptomatic for a long time. Because of its indolent nature it is usually diagnosed at an advanced stage. Clinical presentation is determined by the dissemination of the tumor.

METHOD

A search and analysis of the current literature were carried out.

RESULTS

Based on the morphological characteristics PMP subtypes with various malignant potential can be differentiated. The prognosis depends on the histopathological differentiation and the clinical stage. The treatment spectrum varies from laparoscopic appendectomy to complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC).

CONCLUSION

Due to the rarity of PMP there are no prospective randomized studies. Therefore, there is still controversy regarding the best stage-dependent treatment strategy. This review article attempts to clarify the optimal management of mucinous neoplasms of the appendix and PMP taking the clinical presentation and the histological differentiation into consideration.

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.

Comprehensive Treatment Algorithms of the Swiss Peritoneal Cancer Group for Peritoneal Cancer of Gastrointestinal Origin

Peritoneal cancer (PC) is a dire finding, yet in selected patients, long-term survival is possible. Complete cytoreductive surgery (CRS) together with combination immunochemotherapy is essential to achieve cure. Hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC) are increasingly added to the multimodal treatment. The Swiss Peritoneal Cancer Group (SPCG) is an interdisciplinary group of expert clinicians. It has developed comprehensive treatment algorithms for patients with PC from pseudomyxoma peritonei, peritoneal mesothelioma, gastric, and colorectal origin. They include multimodal neoadjuvant treatment, surgical resection, and palliative care. The indication for and results of CRS HIPEC and PIPAC are discussed in light of the current literature. Institutional volume and clinical expertise required to achieve best outcomes are underlined, while inclusion of patients considered for CRS HIPEC and PIPAC in a clinical registry is strongly advised. The present recommendations are in line with current international guidelines and provide the first comprehensive treatment proposal for patients with PC including intraperitoneal chemotherapy. The SPCG comprehensive treatment algorithms provide evidence-based guidance for the multimodal care of patients with PC of gastrointestinal origin that were endorsed by all Swiss clinicians routinely involved in the multimodal care of these challenging patients.

Validation of a Nomogram to Predict Recurrence in Patients with Mucinous Neoplasms of the Appendix with Peritoneal Dissemination After Cytoreductive Surgery and HIPEC

BACKGROUND

Survival of patients affected by mucinous appendiceal neoplasms with peritoneal dissemination (PD) is mainly related to histopathological features. However, prognostic stratification is still a concern, as the clinical course of the disease is often unpredictable. The aim of this study is to construct and externally validate a nomogram predicting disease-free survival (DFS) in mucinous appendiceal neoplasms with PD treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

PATIENTS AND METHODS

Patients treated in two referral centers were included: Hospital General Universitario Gregorio Marañón, Madrid, Spain (derivation cohort) and Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy (validation cohort). Cox regression analysis identified factors associated with shorter DFS in the derivation cohort. The nomogram performance was externally evaluated in the validation cohort using concordance index and calibration plots. Histology was classified according to the Peritoneal Surface Oncology Group International (PSOGI).

RESULTS

The derivation cohort included 95 patients, and the validation cohort 348. Five-year DFS rates were 51.5 and 62%, respectively. Cox regression analysis (derivation cohort) identified PSOGI histology of the peritoneal components, number of preoperative elevated tumor marker, and peritoneal disease extent, as assessed by peritoneal carcinomatosis index, to be predictors of DFS. The model's predictive capacity was higher than that of PSOGI classification alone, with respective concordance indexes of 0.702 ± 0.023 and 0.610 ± 0.018 (validation cohort). The nomogram approximated the perfect model in the calibration plots at 3- and 5-year DFS.

CONCLUSIONS

An easy-to-use model that provides better prognostic stratification than histopathological features has been constructed. This nomogram may help clinicians in individualized survival predictions and informed clinical decision-making.

Prognosis for Young Females with Pseudomyxoma Peritonei of Appendiceal Origin and Unilateral or Bilateral Ovaries Preserved During Cytoreductive Surgery

Objective

To determine prognosis for young female patients with peritoneal pseudomyxoma (PMP) of appendiceal origin and unilateral or bilateral ovaries preserved during cytoreductive surgery (CRS).

Methods

Clinical data of female patients treated with CRS with or without hyperthermic intraperitoneal chemotherapy (HIPEC) at the Aerospace Center Hospital, Beijing between January, 2009 and December, 2019 were retrospectively reviewed. Patients had no changes in the bilateral ovaries on gross pathological observations or biopsy during CRS, and normal ovarian function. The demographic and clinical characteristics and prognosis of women with ovaries preserved (ovarian preservation group) or resected (ovarian resection group) during CRS were compared. Independent prognostic factors for survival were identified using univariate and multivariate analysis.

Results

40 patients were included in the final analysis. 19 patients chose ovarian preservation while 21 patients underwent ovarian resection. Completeness of cytoreduction (CCR) scores were CCR-0/1. There were significant differences in age (<40 vs. ≥40), symptoms, intraoperative HIPEC (Y vs. N), and histopathologic subtype of PMP (low-grade vs. high-grade) (p < 0.001) between patients in the ovarian preservation and ovarian resection groups. In the ovarian preservation group, median overall survival (OS) was 59 months (range, 53–65 months), and the 5-year survival rate was 37.9%. Median disease-free survival (DFS) was 13 months (range, 9–17 months), and the 5-year recurrence rate was 87.4%. In the ovarian resection group, the 5-year survival rate was 87.7%, and the 5-year recurrence rate was 18.3%. Median OS and median DFS were not reached. In patients with low-grade PMP, median DFS was significantly longer in patients with ovarian resection compared to ovarian preservation (p < 0.001). Univariate analysis showed histopathologic subtype of PMP (low-grade vs. high-grade, p < 0.001) was significantly associated with OS and DFS. On multivariate analysis, high-grade histopathologic subtype of PMP was an independent predictor of poor prognosis (OS and DFS).

Conclusion

Histopathologic subtype of PMP represents an independent predictor of prognosis in female patients with PMP of appendiceal origin and unilateral or bilateral ovaries preserved during CRS. These findings imply that ovarian preservation is a more suitable option for young females with low-grade PMP compared to high-grade PMP. Further prospective studies should be done investigating the role of resection of uninvolved ovaries in PMP.

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.

Inverted Appendix in a Patient With Weakness and Occult Bleeding

BACKGROUND

Appendiceal mucinous neoplasms (AMNs) are rare adenomatous primary tumors of the appendix. Although of low malignant potential, these neoplasms can cause serious potentially fatal complications such as bowel obstruction and pseudomyxoma peritonei, making prompt identification and removal of utmost importance. AMNs often present with nonspecific gastrointestinal symptoms or are asymptomatic and found incidentally.

CASE PRESENTATION

A patient aged 72 years presented with generalized weakness and appeared on imaging to have acute appendicitis complicated by rupture. On colonoscopy, the patient was found to have an inverted appendix that after appendectomy was revealed to harbor a perforated low-grade AMN.

CONCLUSIONS

Although AMNs are rare, physicians should still consider it when imaging suggests appendicitis. Having AMNs as part of the differential diagnosis is especially necessary in cases, such as this one, in which the patient has appendiceal inversion, is aged > 50 years, and has concurrent colorectal neoplasms.

The Correlation Between Intra-Abdominal Pressure and Tolerance to Postoperative Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei

Objective

To evaluate the correlation between pain intensity and comfort level in patients with pseudomyxoma peritoneum (PMP) before and after hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods

From June 2018 to June 2019, patients who underwent HIPEC for PMP after surgical treatment in our institute were selected. The intra-abdominal pressure (IAP) and pain intensity (PI) before and after HIPEC were recorded, and the correlation between them was analyzed.

Results

Seventy-four patients received HIPEC 253 times. IAP and PI were significantly higher after perfusion than before perfusion (P < 0.05). When IAP < 12 cmH₂O, the change of PI was not correlated to the increase of IAP, and the patient tolerated the treatment. However, when IAP > 12 cmH₂O, the increase of PI was significantly associated with IAP and cause significant discomfort during the treatment.

Conclusion

IAP may be a monitoring index for the comfort of PMP patients during the postoperative HIPEC treatment.

The Utility of Preoperative Tumor Markers in Peritoneal Carcinomatosis from Primary Appendiceal Adenocarcinoma: an Analysis from the US HIPEC Collaborative

BACKGROUND

Prognostication based on preoperative clinical factors is lacking in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). This study aims to determine the value of preoperative tumor markers as predictors of progression-free survival (PFS) and overall survival (OS) for patients with peritoneal carcinomatosis from a primary mucinous adenocarcinoma of the appendix (MACA).

METHODS

We queried the United States HIPEC Collaborative, a database of patients with peritoneal carcinomatosis treated with CRS/HIPEC at twelve institutions between 2000 and 2017, identifying 409 patients with MACA. Multivariate analysis was used to identify independent predictors of disease progression. Subgroup analysis was conducted to evaluate the impact of tumor grade on the predictive value of tumor markers.

RESULTS

CA19-9 [HR 2.44, CI 1.2-3.4] emerged as an independent predictor of PFS while CEA [HR 4.98, CI 1.06-23.46] was independently predictive of OS (p <0.01). Tumor differentiation was the most potent predictor of both PFS (poorly differentiated vs well, [HR 4.5 CI 2.01-9.94]) and OS ([poorly differentiated vs well-differentiated: [HR 13.5, CI 3.16-57.78]), p <0.05. Among patients with combined CA19-9 elevation and poorly differentiated histology, 86% recurred within a year of CRS/HIPEC (p < 0.01). Similarly, the coexistence of CEA elevation and unfavorable histology led to the lowest survival rate at two years [36%, p < 0.01]. CA-125 was not predictive of PFS or OS.

CONCLUSION

Elevated preoperative CA19-9 portends worse PFS, while elevated CEA predicts worse OS after CRS/HIPEC in patients with MACA. This study provides additional evidence that CA19-9 and CEA levels should be collected during standard preoperative bloodwork, while CA-125 can likely be omitted. Tumor differentiation, when added to preoperative tumor marker levels, provides powerful prognostic information. Prospective studies are required to confirm this association.

Appendiceal pseudomyxoma peritonei: predictors of recurrence and iterative surgery

AIM

Appendiceal pseudomyxoma peritonei (PMP) is a rare entity, with recurrence rates up to 26% despite optimal cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Evidence specific to PMP originating from non-infiltrative appendiceal mucinous neoplasms (low grade - LAMN and high grade - HAMN) is lacking. The aim of this study was to identify patterns of recurrence and predictive factors for patients appropriate for iterative surgery.

METHOD

A bi-institutional retrospective analysis was performed on patients undergoing complete cytoreduction and HIPEC for PMP derived from perforated LAMN or HAMN. Multivariate logistic regression was performed to identify independent predictors for re-do CRS. Five-year overall survival (OS) was stratified according to surgical intervention, and 5-year disease-free survival (DFS) was stratified according to histological PMP grade. Cox regression analysis was performed to identify independent predictors for OS and DFS.

RESULTS

Sixty of 239 (25.1%) patients developed peritoneal recurrence between 2007 and 2020. The median time to recurrence was 20.7 months. The risk of disease recurrence was highest with high-grade PMP (P <0.001) and increasing PCI (P <0.001). Patients with high-grade histology from their index procedure and aged over 60 years were less likely to be offered iterative surgery on multivariate analysis. Patients who underwent iterative CRS and HIPEC had a 5-year survival of 100%.

CONCLUSION

Iterative CRS and HIPEC is feasible in selected patients with recurrent PMP, displaying good oncological outcomes. Age, index histology and level of abdominal quadrant involvement are predictive of proceeding to re-do surgery.

The effect of intraperitoneal administration of BromAc on blood parameters: phase 1 study

Intraperitoneal administration of BromAc (bromelain + acetylcysteine) is currently undergoing a phase 1 clinical trial for pseudomyxoma peritonei at our institution. This study reports on analysis of routine blood parameters before and after treatment for a series of 25 patients in this trial. Blood parameters assessed included full blood count, electrolytes, urea, and creatinine, liver function tests, coagulation studies, as well as inflammatory markers (CRP). Certain parameters such as CRP, and white cell count, were significantly elevated after treatment whilst serum albumin level was reduced indicating an inflammatory reaction. However, liver enzymes, coagulation studies, and other parameters were not affected. Therefore, there are no additional safety signals evident upon analysis of routine blood parameter testing.

Patterns of peritoneal dissemination and response to systemic chemotherapy in common and rare peritoneal tumours treated by cytoreductive surgery: study protocol of a prospective, multicentre, observational study

INTRODUCTION

Despite optimal patient selection and surgical effort, recurrence is seen in over 70% of patients undergoing cytoreductive surgery (CRS) for peritoneal metastases (PM). Apart from the Peritoneal Cancer Index (PCI), completeness of cytoreduction and tumour grade, there are other factors like disease distribution in the peritoneal cavity, pathological response to systemic chemotherapy (SC), lymph node metastases and morphology of PM which may have prognostic value. One reason for the underutilisation of these factors is that they are known only after surgery. Identifying clinical predictors, specifically radiological predictors, could lead to better utilisation of these factors in clinical decision making and the extent of peritoneal resection performed for different tumours. This study aims to study these factors, their impact on survival and identify clinical and radiological predictors.

METHODS AND ANALYSIS

There is no therapeutic intervention in the study. All patients with biopsy-proven PM from colorectal, appendiceal, gastric and ovarian cancer and peritoneal mesothelioma undergoing CRS will be included. The demographic, clinical, radiological, surgical and pathological details will be collected according to a prespecified format that includes details regarding distribution of disease, morphology of PM, regional node involvement and pathological response to SC. In addition to the absolute value of PCI, the structures bearing the largest tumour nodules and a description of the morphology in each region will be recorded. A correlation between the surgical, radiological and pathological findings will be performed and the impact of these potential prognostic factors on progression-free and overall survival determined. The practices pertaining to radiological and pathological reporting at different centres will be studied.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Zydus Hospital ethics committee (27 July, 2020) and Lyon-Sud ethics committee (A15-128).

TRIAL REGISTRATION NUMBER

CTRI/2020/09/027709; Pre-results.

Managing Recurrent Pseudomyxoma Peritonei in 430 Patients After Complete Cytoreduction and HIPEC: A Dilemma for Patients and Surgeons

BACKGROUND

Epithelial appendiceal neoplasms are uncommon peritoneal malignancies causing a spectrum of disease including pseudomyxoma peritonei (PMP). The optimal management is cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Despite complete CRS (CCRS), recurrence develops in almost 45% of patients. No consensus exists for the optimal treatment of recurrent disease, with treatment strategies including repeat CRS, watch-and-wait, and palliative chemotherapy. This report aims to describe evolving management strategies for a large cohort with recurrence after CCRS.

METHODS

This retrospective study analyzed a prospective database of patients with recurrence after CCRS for appendiceal neoplasms from 1994 to 2017 who had long-term follow-up evaluation with tumor markers and computed tomography (CT).

RESULTS

Overall, 430 (37.6%) of 1145 PMP patients experienced recurrence at a median of 19 months. Of these 430 patients 145 (33.7%) underwent repeat CRS, 119 (27.7%) had a watch-and-wait approach, and 119 (27.7%) had palliative chemotherapy. The patients with recurrence had a median overall survival (OS) of 39 months, a 3-year survival of 74.6%, a 5-year survival of 57.4%, and a 10-year survival of 36.5%. In the multivariate analysis, the patients who had recurrence within 1 year after primary CRS (hazard ratio [HR], 3.55), symptoms at recurrence (HR, 3.08), a high grade of disease or adenocarcinoma pathology (HR, 2.94), signet ring cells (HR, 1.91), extraperitoneal metastatic disease (HR, 1.71), or male gender (HR, 1.61) had worse OS. The OS was longer for the patients who had repeat CRS (HR, 0.41). The patients who underwent repeat CCRS had a 3-year OS of 87.5%, a 5-year OS of 78.1%, and a 10-year OS of 67.9%.

CONCLUSIONS

Dilemmas persist around the optimal management of patients with recurrence after CRS and HIPEC for appendiceal tumors. Selected patients benefit from repeat CRS, particularly those with favorable tumor biology and focal disease.

Ki67 does not predict recurrence for low-grade appendiceal mucinous neoplasms with peritoneal dissemination after cytoreductive surgery and HIPEC

Low-grade appendiceal mucinous neoplasms (LAMN) can disseminate to become low-grade mucinous carcinoma peritonei (LGMCP), which is optimally treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Approximately half of the patients with LGMCP recur despite complete cytoreduction, and risk factors for recurrence are poorly understood. We sought to evaluate if Ki67 predicts progression of LGMCP after CRS/HIPEC. A retrospective review of a prospectively maintained database was performed to identify patients treated with complete CRS/HIPEC for LGMCP from 2008 to 2019 with Ki67 assessed. Patient characteristics, histologic data, average and focally high "hotspot") Ki67 index, progression-free survival (PFS), and overall survival (OS) were analyzed. Ki-67 immunostain was performed on the histologic section with the highest cellularity and architectural complexity. Forty-four patients with LGMCP (55% male, median age 61) were identified. The median Ki67 score and hotspot Ki67 score was 15% (1-70) and 50% (1-90), respectively. On univariate analysis, average Ki67 and hotspot Ki67 were not predictive of PFS when analyzed as continuous normalized values (HR 1.0, p = 0.79 and HR 1.1, p = 0.38, respectively) or as categorical values when stratified by the median (HR 0.9, p = 0.67 and HR 1.0, p = 0.93). This remained true on multivariate analysis when stratified for peritoneal cancer index, CEA, and completeness of cytoreduction score for both normalized Ki67 and hotspot Ki67 (HR 0.9 [95% CI 0.8-1.3], p = 0.94 and HR 1.04 [95% CI 0.8-1.3], p = 0.73, respectively). Ki67 failed to predict disease recurrence for patients with LGMCP in this cohort.

Two-step cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei with high peritoneal carcinomatosis index

BACKGROUND

Complete cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is the only curative treatment for pseudomyxoma peritonei (PMP) arising from the appendix. High peritoneal carcinomatosis index (PCI) is associated with an increased risk of surgical complications. The objective of this study was to present the results of a planned two-step surgical strategy to decrease postoperative morbidity and improve resectability of patients with very high PCI.

METHODS

All consecutive patients who underwent a planned two-step surgical approach for PMP between January 2012 and March 2020 were retrospectively included. This approach was offered for patients with low-grade PMP with PCI > 28 for which feasibility of a complete CRS in one operation was uncertain. The first surgery included a complete CRS of the inframesocolic compartment and omentectomy. HIPEC was delivered at the second surgery, after complete CRS of the supramesocolic compartment. Postoperative morbidity was assessed using the Clavien-Dindo classification and survival results were also collected.

RESULTS

Eight patients underwent the two-step approach. The median PCI was 33 (29-39) and the median time between the two procedures was 111 days (90-212 days). One patient was deemed unresectable at the second surgery. The rate of major morbidity was 0% for the first step and 25% for the second step, with no mortality. Median follow-up was 53.8 months (3-73 months).

CONCLUSION

A two-step surgical management for low-grade PMP patients with very high PCI is safe and feasible, with acceptable postoperative morbidity and no compromise on oncological outcomes.

Impact of Perioperative Blood Transfusions on Outcomes After Hyperthermic Intraperitoneal Chemotherapy: A Propensity-Matched Analysis

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a major operation frequently necessitating red blood cell transfusion. Using multi-institutional data from the U.S. HIPEC Collaborative, this study sought to determine the association of perioperative allogenic blood transfusion (PABT) with perioperative outcomes after CRS/HIPEC.

METHODS

This retrospective cohort study analyzed patients who underwent CRS/HIPEC for peritoneal surface malignancy between 2000 and 2017. Propensity score-matching was performed to mitigate bias. Univariate analysis was used to compare demographic, preoperative, intraoperative, and postoperative variables. Factors independently associated with PABT were identified using multivariate analysis.

RESULTS

The inclusion criteria were met by 1717 patients, 510 (29.7%) of whom required PABT. The mean Peritoneal Cancer Index (PCI) of our cohort was 14.8 ± 9.3. Propensity score-matching showed an independent association between PABT and postoperative risk of pleural effusion, hemorrhage, pulmonary embolism, enteric fistula formation, Clavien-Dindo grades 3 and 4 morbidity, longer hospital stay, and reoperation (all P < 0.05 in the multivariate analysis). Compared with the patients who received 1 to 5 red blood cell (RBC) units, the patients who received more than 5 units had a greater risk of renal impairment, a longer intensive care unit (ICU) stay, and more postoperative infections. Finally, PABT was an independent predictor of worse survival for patients with appendiceal and colorectal primaries.

CONCLUSION

Even low levels of PABT for patients undergoing CRS/HIPEC are independently associated with a greater risk of infectious and non-infectious postoperative complications, and this risk is increased for patients receiving more than 5 RBC units. Worse survival was independently predicted by PABT for patients with peritoneal carcinomatosis of an appendiceal or colorectal origin.

Retrospective Study of the Epidemiology, Pathology, and Therapeutic Management in Patients With Mucinous Ovarian Tumors

Aim:

We sought to determine the epidemiology of mucinous ovarian tumors, the correlation between serum biomarkers and tumor status, and the outcomes of the management in different subtypes of mucinous ovarian tumors in a Chinese surgical cohort.

Methods:

A total of 513 patients were enrolled from January 2009 to May 2017. The number of patients who had benign mucinous ovarian tumor, borderline mucinous ovarian tumor, or malignant mucinous ovarian tumor was pathologically quantified. All patients underwent surgery with or without postoperative adjuvant therapy. Prognosis was analyzed based on clinicopathological characteristics and the type of treatment received. Hyperthermic intraperitoneal chemotherapy efficacy and adverse effects in patients were also explored.

Results:

In all, 383 (75%) patients were diagnosed as having benign mucinous ovarian tumor, 76 (14%) patients with borderline mucinous ovarian tumor, and 54 (5%) patients with malignant mucinous ovarian tumor. Levels of serum biomarkers increased as the tumors became more malignant. Patients with stage IA and IC (unilateral) malignant mucinous ovarian tumor who underwent fertility conserving surgery did not experience poorer prognoses when compared to those who received non-fertility conserving surgery. Hyperthermic intraperitoneal chemotherapy followed by chemotherapy significantly influenced survival rates in patients with a ruptured malignant mucinous ovarian tumor.

Conclusions:

Levels of serum tumor markers, carbohydrate antigen 125, carbohydrate antigen 199, carbohydrate antigen 242, and carcinoembryonic antigen may be useful in monitoring for malignant transformation. Fertility conserving surgery might be a preferable surgical procedure for patients with malignant mucinous ovarian tumor at early stage (IA and IC [unilateral]). Hyperthermic intraperitoneal chemotherapy appears to be a well-tolerated and promising postoperative adjuvant.

A comprehensive review of childbearing after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

PURPOSE

Our aim is to present a review on childbearing following CRS and HIPEC for peritoneal malignancy.

METHODS

A review of the English literature, up to December 2019, was conducted, using PubMed/MEDLINE, EmBase and Google Scholar bibliographic databases, following the MOOSE guidelines. The terms "Cytoreductive Surgery", "Hyperthermic Intraperitoneal Chemotherapy", "Peritoneal Carcinomatosis", "Pregnancy", "Fertility Preservation", "Conception" were used. All study designs were eligible for inclusion in the final analysis.

RESULTS

In total, 7 studies (5 case reports and 2 case series) were included in the final analysis, reporting on 14 successful pregnancies after CRS and HIPEC. The mean age of patients at the time of CRS/HIPEC was 28.8 ± 5.9 years (range 18-36), while the mean interval between CRS/HIPEC and pregnancy was 29.6 ± 20.3 months (range 9-80 months). Nine patients were treated for pseudomyxoma peritonei, four for primary peritoneal mesothelioma and one for endocrine carcinoma. Mean Peritoneal Carcinomatosis Index was 9.8 ± 7.8 (range 1-26). All patients underwent fertility-sparing CRS (preservation of at least one ovary and the uterus). In 12 cases, conception was spontaneous, whereas two pregnancies were achieved through in-vitro fertilization. One patient developed gestational hypertension, while two labors were preterm. Mean disease-free survival was 64.1 months (range 24-106 months).

CONCLUSION

A successful pregnancy is feasible in selected patients, after CRS and HIPEC. Assisted reproduction techniques (IVF using frozen oocytes or frozen embryos, ovarian tissue cryopreservation, preoperative treatment with GnRH analogs) should be discussed pre-operatively with the patient, without, however, compromising overall survival or risking locoregional recurrence.

Predictors of Non-home Discharge after Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Using a national database of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) recipients, we sought to determine risk factors for nonhome discharge (NHD) in a cohort of patients.

METHODS

Patients undergoing CRS/HIPEC at any one of 12 participating sites between 2000 and 2017 were identified. Univariate analysis was used to compare the characteristics, operative variables, and postoperative complications of patients discharged home and patients with NHD. Multivariate logistic regression was used to identify independent risk factors of NHD.

RESULTS

The cohort included 1593 patients, of which 70 (4.4%) had an NHD. The median [range] peritoneal cancer index in our cohort was 14 [0-39]. Significant predictors of NHD identified in our regression analysis were advanced age (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.05-1.12; P < 0.001), an American Society of Anesthesiologists (ASA) score of 4 (OR, 2.87; 95% CI, 1.21-6.83; P = 0.017), appendiceal histology (OR, 3.14; 95% CI 1.57-6.28; P = 0.001), smoking history (OR, 3.22; 95% CI, 1.70-6.12; P < 0.001), postoperative total parenteral nutrition (OR, 3.14; 95% CI, 1.70-5.81; P < 0.001), respiratory complications (OR, 7.40; 95% CI, 3.36-16.31; P < 0.001), wound site infections (OR, 3.12; 95% CI, 1.58-6.17; P = 0.001), preoperative hemoglobin (OR, 0.81; 95% CI, 0.70-0.94; P = 0.006), and total number of complications (OR, 1.41; 95% CI, 1.16-1.73; P < 0.001).

CONCLUSIONS

Early identification of patients at high risk for NHD after CRS/HIPEC is key for preoperative and postoperative counseling and resource allocation, as well as minimizing hospital-acquired conditions and associated health care costs.

Estimating the Prevalence of Pseudomyxoma Peritonei in Europe Using a Novel Statistical Method

Background

The determination of the incidence and prevalence of rare diseases is important for economists and health-care providers. Pseudomyxoma peritonei (PMP) is a rare, slow-growing abdominal cancer that represents a substantial burden on both patients and health-care systems. The incidence rate was previously approximated at 1–2 people per million per year; this incidence has never been challenged, and the prevalence has not been estimated.

Methods

Epidemiological data from Norway and England were obtained and analysed to calculate a minimum incidence rate based on the number of patients having a first surgical intervention for PMP. A novel method was then used to determine a prevalence rate for PMP, incorporating incidence, death, and cure rates in a multi-year analysis that accounted for the increasing population of Europe over a 10-year period.

Results

An incidence rate of 3.2 people per million per year was calculated, with a corresponding estimated prevalence rate of 22 people per million per year. By this calculation, 11,736 people in Europe were estimated to be living with PMP in 2018.

Conclusion

Incidence and prevalence are essential tools for assessment of the financial and human cost of a disease. For rare diseases, such as PMP, the lack of accurate registries presents a particular challenge in determining such health-related statistical parameters. Based on our calculations, a significant number of people are living with PMP in Europe, underlining the need for appropriate resource allocation to ensure that adequate health-care measures are provided.

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.