Systemic chemotherapy (SC) before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in patients with peritoneal mucinous carcinomatosis of appendiceal origin (PMCA)

Predicting Survival in Mucinous Adenocarcinoma of the Appendix: Demographics, Disease Presentation, and Treatment Methodology

BACKGROUND

Mucinous adenocarcinoma of the appendix (MACA) follows a complex disease course with variable survival. Large-scale predictive modeling may determine subtle yet important prognostic factors otherwise unseen in smaller cohort analyses.

METHODS

Patients with MACA were identified from the Surveillance, Epidemiology, and End Results (SEER) Research Plus database (2005-2019). Primary, secondary, and tertiary outcomes were disease-specific survival (DSS), overall survival (OS), and average annual percent change (AAPC) in incidence.

RESULTS

Among 4,258 included patients, MACA was most frequently diagnosed at 50 to 69 years (52.0%), with female preponderance (55.9%). MACA incidence AAPC was 3.8 (95% confidence interval [CI] 1.9-5.9). For patients with exclusive, first-diagnosis MACA included in survival analysis (3,222 patients), median DSS and OS were 118 and 88 months, respectively. In DSS-based multivariable analysis, worse prognosis was associated with non-Hispanic Black background (HR 1.36, 95% CI 1.02-1.82; p = 0.036), high grade (grade 3 HR 3.10, 95% CI 2.44-3.92; p < 0.001), lymphatic spread (HR 2.73, 95% CI 2.26-3.30; p < 0.001), and distant metastasis (HR 5.84, 95% CI 3.86-8.83; p < 0.001). In subcohort analysis of patients with rationale for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC, 2,387 patients), CRS-HIPEC was associated with survival benefit compared with surgery alone but only for moderate-grade tumors (median DSS/OS 138/138 vs. 116/87 months; p < 0.001).

CONCLUSIONS

Mucinous adenocarcinoma of the appendix incidence is increasing in the United States. Survival rates are affected by both demographics and classical risk factors, and CRS-HIPEC-associated survival benefit predominantly occurs in moderate-grade tumors. Further exploration of biologic and clinicopathologic features may enhance risk stratification for this disease.

Top Peritoneal Surface Malignancy Articles from 2022 to Inform your Cancer Practice

Over the last few decades, the role of cytoreductive surgery (CRS) with or without regional-based peritoneal therapies such as hyperthermic intraperitoneal chemotherapy (HIPEC) has evolved in the management of patients with peritoneal surface malignances (PSMs). Despite the benefit of CRS in improving oncologic outcomes, significant challenges remain in the treatment of patients with advanced PSMs, and the role of HIPEC continues to be questioned. Additionally, while there has been improvement in perioperative outcomes, long-term survival remains poor. As a result, there is much need to improve our understanding of the processes that drive tumor biology, thereby improving patient selection for various treatment approaches. Additionally, newer therapies are needed for patients who remain poor surgical candidates and who progress on systemic therapy. This article highlights recently published studies that we consider impactful in the care of patients with PSMs.

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.

Fragmentation of Care in Patients with Peritoneal Metastases Undergoing Cytoreductive Surgery

BACKGROUND

The delivery of multimodal treatment at a high-volume center is known to optimize the outcomes of gastrointestinal malignancies. However, patients undergoing cytoreductive surgery (CRS) for peritoneal metastases often must 'fragment' their surgical and systemic therapeutic care between different institutions. We hypothesized that this adversely affects outcomes.

PATIENTS AND METHODS

Adults undergoing CRS for colorectal or appendiceal adenocarcinoma at our institution between 2016 and 2022 were identified retrospectively and grouped by care network: 'coordinated care' patients received exclusively in-network systemic therapy, while 'fragmented care' patients received some systemic therapy from outside-network providers. Factors associated with fragmented care were also ascertained. Overall survival (OS) from CRS and systemic therapy-related serious adverse events (SAEs) were compared across the groups.

RESULTS

Among 85 (80%) patients, 47 (55%) had colorectal primaries and 51 (60%) received fragmented care. Greater travel distance [OR 1.01 (CI 1.00-1.02), p = 0.02] and educational status [OR 1.04 (CI 1.01-1.07), p = 0.01] were associated with receiving fragmented care. OS was comparable between patients who received fragmented and coordinated care in the colorectal [32.5 months versus 40.8 months, HR 0.95 (CI 0.43-2.10), p = 0.89] and appendiceal [31.0 months versus 27.4 months, HR 1.17 (CI 0.37-3.74), p = 0.55] subgroups. The frequency of SAEs (7.8% versus 17.6%, p = 0.19) was also similar.

CONCLUSIONS

There were no significant differences in survival or SAEs based on the networks of systemic therapy delivery. This suggests that patients undergoing CRS at a high-volume center may safely receive systemic therapy at outside-network facilities with comparable outcomes.

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.

Defining a role for systemic chemotherapy in local and advanced appendix adenocarcinoma

BACKGROUND

Appendix adenocarcinomas (AAs) are rare tumours that often present late, with a propensity for peritoneal metastases (PMs). This study aimed to evaluate outcomes of AA patients undergoing cytoreductive surgery (CRS) with curative intent and determine the role of systemic chemotherapy.

MATERIALS AND METHODS

Data were collected from a prospective database and classified according to World Health Organization (WHO) 2019 classification. Tumour clearance from CRS was described using a completeness of cytoreduction (CC) score ranging from 0 [no residual disease (RD)] to 3 (>2.5 cm RD). Patients with CC0-2 CRS received hyperthermic intraperitoneal chemotherapy (HIPEC). Systemic chemotherapy was categorised as 'prior' (>6 months before), 'neoadjuvant' (<6 months before), 'adjuvant' (<6 months after CC0-1 CRS) or 'palliative' (after CC2-3 CRS). Analyses used Kaplan-Meier and Cox regression methods.

RESULTS

Between January 2005 and August 2021, 216 AA patients were identified for inclusion. Median age was 59 years (21-81 years). CRS/HIPEC was carried out in 182 (84%) patients, of whom 164/182 (76%) had mitomycin C HIPEC. CC0-1 was achieved in 172 (80%) patients. Systemic chemotherapy was given to 97 (45%) patients from the whole cohort and to 37/46 (80%) patients with positive nodes. Median overall survival (OS) was 122 months (95% confidence interval 61-182 months). After multivariate analysis, patients with acellular and lower-grade PM had similar OS to those with localised (M0) disease (P = 0.59 and P = 0.19). For patients with positive nodes, systemic chemotherapy was associated with reduced risk of death compared to no chemotherapy (P < 0.0019).

CONCLUSION

This study identifies AA patients with positive lymph nodes derive the most benefit from systemic chemotherapy. We confirm the prognostic importance of stage and peritoneal grade, with excellent outcomes in patients with acellular mucin and lower-grade PM.

Neoplasms of the Appendix

BACKGROUND

Neoplasms of the vermiform appendix are rare. They comprise a heterogeneous group of entities requiring differentkinds of treatment.

METHODS

This review is based on publications retrieved by a selective literature search in the PubMed, Embase, and Cochranedatabases.

RESULTS

0.5% of all tumors of the gastrointestinal tract arise in the appendix. Their treatment depends on their histopathologicalclassification and tumor stage. The mucosal epithelium gives rise to adenomas, sessile serrated lesions, adenocarcinomas,goblet-cell adenocarcinomas, and mucinous neoplasms. Neuroendocrine neoplasms originate in neuroectodermal tissue. Adenomasof the appendix can usually be definitively treated by appendectomy. Mucinous neoplasms, depending on their tumorstage, may require additional cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemoperfusion (HIPEC). Adeno -carcinomas and goblet-cell adenocarcinomas can metastasize via the lymphatic vessels and the bloodstream and should thereforebe treated by oncological right hemicolectomy. Approximately 80% of neuroendocrine tumors are less than 1 cm in diameterwhen diagnosed and can therefore be adequately treated by appendectomy; right hemicolectomy is recommended if the patienthas risk factors for metastasis via the lymphatic vessels. Systemic chemotherapy has not been shown to be beneficial forappendiceal neoplasms in prospective, randomized trials; it is recommended for adenocarcinomas and goblet-cell adenocarcinomasof stage III or higher, in analogy to the treatment of colorectal carcinoma.

Appendiceal Mucinous Neoplasms: From Clinic to Pathology and Prognosis

Appendiceal mucinous neoplasms have been classified differently over time causing confusion when comparing results between working groups in this field and establishing a prognosis of the disease. A historical perspective of the different classification systems of these tumors is essential for the understanding of the evolution of concepts and histopathological definitions that have led up to the present moment. We carried out a systematic review of the pathological classifications of appendiceal mucinous tumors and how they have included the new criteria resulting from clinical and pathological research. The latest classifications by PSOGI and AJCC 8th edition Cancer Staging have made a great effort to incorporate the new pathological descriptions and develop prognostic groups. The introduction of these new classification systems has posed the challenge of verifying how they adapt to our casuistry and which one defines best the prognosis of our patients. We reclassified our series of patients treated for mucinous appendiceal tumors with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy following the PSOGI and the AJCC 8th edition criteria and concluded that both classifications correspond well with the OS and DFS of these patients, with some advantage relative to the PSOGI classification due to a better histopathological description of the different groups.

Correlation between PSOGI pathological classification and survival outcomes of patients with pseudomyxoma peritonei treated using cytoreductive surgery and HIPEC: national referral centre experience and literature review

Objectives

The Peritoneal Surface Oncology Group International (PSOGI) consensus subdivided pseudomyxoma peritonei (PMP) into four groups according to histopathological features. The aim of this paper is to report survival outcomes after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) from a national referral centre and to correlate the PSOGI classification with survival.

Methods

A retrospective study of a prospectively maintained database was performed. Consecutive patients treated with CRS + HIPEC for PMP of appendiceal origin were included (September-2013 to December-2021). Pathological features of the peritoneal disease were used to classify patients into the four groups proposed by PSOGI. Survival analysis was performed to evaluate the correlation of pathology on overall survival (OS) and disease-free survival (DFS).

Results

Overall, 104 patients were identified; 29.6 % were reclassified as acellular mucin (AM), 43.9 % as low-grade mucinous carcinoma peritonei (LGMCP), 22.4 % as high-grade MCP (HGMCP) and 4.1 % as HGMCP with signet ring cells (HGMCP-SRC). Median PCI and rate of optimal cytoreduction were 19 and 82.7 %, respectively. Median OS and DFS were not reached, 5-year OS and DFS were 88.6(SD 0.04) % and 61.6(SD 0.06) %, respectively. Log-Rank test revealed significant differences in terms of OS and DFS across the different histological subgroups (p<0.001 in both cases). However, histology did not retain its significance in the multivariate analysis for OS or DFS (p=0.932 and p=0.872, respectively).

Conclusions

Survival outcomes after CRS + HIPEC for PMP are excellent. The PSOGI pathological classification correlates with OS and DFS, but differences were not significant at multivariate analysis when adjusted for other prognostic factors.

Association of Systemic Chemotherapy Approaches With Outcomes in Appendiceal Peritoneal Metastases

INTRODUCTION

Many patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for appendiceal adenocarcinoma peritoneal metastases (APM) undergo preoperative systemic chemotherapy. The primary aim of this study is to evaluate differences in oncologic outcomes among two popular chemotherapy approaches in patients with APM undergoing CRS-HIPEC.

METHODS

We performed a multicenter retrospective review of patients who underwent CRS-HIPEC for APM due to high or intermediate grade disease between 2013 and 2019. Patients in the total neoadjuvant therapy group (TNT) received 12 cycles of preoperative chemotherapy. Patients in the "sandwich" chemotherapy group (SAND) received six cycles of preoperative chemotherapy with a maximum of six cycles of postoperative chemotherapy. The primary outcomes were overall survival (OS) and recurrence-free survival (RFS) defined as months from date of first treatment or surgery, respectively.

RESULTS

A total of 39 patients were included in this analysis, with 25 (64%) patients in the TNT group and 14 (36%) patients in the SAND group. Patients in the TNT group had a median OS of 62 mo, while median OS in the SAND group was 45 mo (P = 0.01). In addition, patients in the TNT group had significantly longer RFS compared to the SAND group (35 versus 12 mo, P = 0.03). In a multivariable analysis, TNT approach was independently associated with improved OS and RFS.

CONCLUSIONS

In this multicenter retrospective analysis, a TNT approach was associated with improved overall and recurrence-free survival compared to a sandwiched chemotherapy approach in patients undergoing CRS-HIPEC for high or intermediate grade APM.

Impact of neoadjuvant systemic chemotherapy followed by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for appendiceal adenocarcinoma

AIM

Peritoneal dissemination of infiltrative appendiceal tumors is a rare and poorly understood phenomenon. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a well-recognized treatment option for selected patients. Neoadjuvant systemic chemotherapy (NAC) has been shown to be associated with improved overall survival (OS) in colorectal peritoneal metastases but little is known of the impact of this from an appendiceal adenocarcinoma perspective.

METHOD

A prospective database of 294 patients with advanced appendiceal primary tumors undergoing CRS ± HIPEC between June 2009 and December 2020 was reviewed. Baseline characteristics and long-term outcomes were compared between patients with adenocarcinoma who received neoadjuvant chemotherapy or upfront surgery.

RESULTS

Eighty-six (29%) patients were histologically diagnosed with an appendiceal cancer. These included intestinal-type adenocarcinoma (11.6%), mucinous adenocarcinoma (43%), and goblet cell adenocarcinoma (GCA) or signet ring cell adenocarcinoma (SRCA) (45.4%). Twenty-five (29%) of these underwent NAC, of which eight (32%) exhibited some degree of radiological response. There was no statistical difference in OS at 3 years between the NAC and upfront surgery groups (47.3% vs. 75.8%, p = 0.372). Appendiceal histology subtypes, particularly GCA and SRCA (p = 0.039) and peritoneal carcinomatosis index >10 (p = 0.009), were factors independently associated with worse OS.

CONCLUSION

Administration of NAC did not appear to prolong OS in the operative management of disseminated appendiceal adenocarcinomas. GCA and SRCA subtypes display a more aggressive biological phenotype.

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 contemporary management of peritoneal metastasis: A journey from the cold past of treatment futility to a warm present and a bright future

Peritoneal metastasis (PM) is often regarded as a less frequent pattern of spread; however, collectively across all spectra of primary tumors, the consequences of PM impact a large population of patients annually. Unlike other modes of metastasis, symptoms at presentation or during the treatment course are common, representing an additional challenge in the management of PM. Early efforts with chemotherapy and incomplete surgical interventions transiently improved symptoms, but durable symptom control and survival extension were rare, which established a perspective of treatment futility for PM through most of the 20th century. Notably, the continued development of better systemic therapy combinations, optimization of cytoreductive surgery (CRS), and rigorous investigation of combining regional therapy-specifically hyperthermic intraperitoneal chemotherapy-with CRS, have resulted in more effective multimodal treatment options for patients with PM. In this article, the authors provide a comprehensive review of the data establishing the contemporary approach for tumors with a high frequency of PM, including appendix, colorectal, mesothelioma, and gastric cancers. The authors also explore the emerging role of adding hyperthermic intraperitoneal chemotherapy to the well established paradigm of CRS and systemic therapy for advanced ovarian cancer, as well as the recent clinical trials identifying the efficacy of poly(adenosine diphosphate ribose) polymerase maintenance therapy. Finally, recent data are included that explore the role of precision medicine technology in PM management that, in the future, may help further improve patient selection, identify the best systemic therapy regimens, detect actionable mutations, and identify new targets for drug development.

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

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.

The Landmark Series: Appendiceal Primary Peritoneal Surface Malignancy

Appendiceal primary peritoneal surface malignancies are rare and include a broad spectrum of pathologies ranging from indolent disease to aggressive disease. As such, the data that drive the management of appendiceal peritoneal surface malignancies is generally not based on prospective clinical trial data, but rather consists of level 1 data based on retrospective studies and high-volume institutional experiences. Complete surgical debulking typically offers the best chance for long-term survival. This review highlights the landmark articles on which management of primary appendiceal peritoneal surface malignancies are based.

Incidentally found mucinous epithelial tumors of the appendix with or without pseudomyxoma peritonei: diagnostic and therapeutic algorithms based on current evidence

Mucinous appendiceal tumors with or without the pseudomyxoma peritonei (PMP) syndrome are rare, but often present as an incidental finding. The confusing histology and lack of large prospective trials result in a considerable diagnostic and therapeutic challenge in these patients. We propose treatment algorithms in patients with incidentally found mucinous epithelial appendiceal tumors, with or without PMP, based on the currently available evidence. The therapeutic approach should take into account the histology and grade of the primary appendix tumor, as well as those of the associated peritoneal disease.

Consensuses and controversies on pseudomyxoma peritonei: a review of the published consensus statements and guidelines

Background

Pseudomyxoma peritonei (PMP) is a clinical malignant syndrome mainly originating from the appendix, with an incidence of 2–4 per million people. As a rare disease, an early and accurate diagnosis of PMP is difficult. It was not until the 1980s that the systematic study of this disease was started.

Main body

As a result of clinical and basic research progress over the last 4 decades, a comprehensive strategy based on cytoreductive surgery (CRS) + hyperthermic intraperitoneal chemotherapy (HIPEC) has been established and proved to be an effective treatment for PMP. Currently, CRS + HIPEC was recommended as the standard treatment for PMP worldwide. There are several consensuses on PMP management, playing an important role in the standardization of CRS + HIPEC. However, controversies exist among consensuses published worldwide. A systematic evaluation of PMP consensuses helps not only to standardize PMP treatment but also to identify existing controversies and point to possible solutions in the future. The controversy underlying the consensus and vice versa promotes the continuous refinement and updating of consensuses and continue to improve PMP management through a gradual and continuous process. In this traditional narrative review, we systemically evaluated the consensuses published by major national and international academic organizations, aiming to get a timely update on the treatment strategies of CRS + HIPEC on PMP.

Conclusion

Currently, consensuses have been reached on the following aspects: pathological classification, terminology, preoperative evaluation, eligibility for surgical treatment, maximal tumor debulking, CRS technical details, and severe adverse event classification system. However, controversies still exist regarding the HIPEC regimen, systemic chemotherapy, and early postoperative intraperitoneal chemotherapy.

Surgical and oncological outcomes after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy at a nonacademic center: 25-year experience

BACKGROUND

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is predominantly performed and studied in academic centers. While developing CRS/HIPEC programs in nonacademic hospitals can increase accessibility, its safety and oncological efficacy remains unclear. We evaluated CRS/HIPEC outcomes in a nonacademic setting.

METHODS

A single-center descriptive study was conducted using a prospective database. Data of all CRS/HIPEC attempts in peritoneal surface malignancies (PSM) patients from October 1994 to November 2019 were extracted. Surgical and survival outcomes were measured. Center experience was assessed by quartiles of cases.

RESULTS

Overall, 856 patients underwent 948 CRS/HIPEC attempts: 788 (83%) completed CRS/HIPECs, 144 (15%) aborted HIPECs, and 16 (2%) complete cytoreductions (CC-0/1) without chemoperfusion. For completed CRS/HIPECs, median peritoneal cancer index was 24 (interquartile range: 10-33) and CC-0/1 rate was 88%. Major complications occurred in 23.5% with 30- and 100-day mortality of 1.0% and 2.3%, respectively. Median overall survival was 68 months (95% confidence interval [CI]: 50-86). Median progression-free survival was 37 months (95%CI: 28-46). Incomplete cytoreduction and major complication rates decreased over time, while mortality remained low and constant.

CONCLUSIONS

CRS/HIPEC at a nonacademic center with advanced surgical and auxiliary services is a safe option to treat PSM with favorable surgical and oncological outcomes.

Women survive longer than men undergoing cytoreductive surgery and HIPEC for appendiceal cancer

BACKGROUND

We hypothesize that women undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis from appendiceal cancer will have a survival advantage compared to men.

METHODS

The National Cancer Database (NCDB) public user file (2004-2014) was used to select patients with PC undergoing CRS and HIPEC from appendiceal cancer. Univariate and multivariable analyses were performed.

RESULTS

1,190 patients with PC from appendiceal cancer underwent HIPEC and CRS. OS was significantly longer for women than for men, with mean and median OS being 73.8 months and 98.2 months for women vs 58.7 months and 82.5 months for men, respectively (p = 0.0032). On multivariable analysis, male sex (HR: 1.444, 95% CI: 1.141-1.827, p = 0.0022) and increasing age (HR: 1.017, 95% CI: 1.006-1.027, p = 0.0017) were both found to be independent risk factors for worse OS.

CONCLUSION

Women undergoing CRS and HIPEC for PC from appendiceal origin live longer than men undergoing the same treatment. Increasing age was also found to be independent risk factors for worse survival.

Quality analysis of operative reports and referral data for appendiceal neoplasms with peritoneal dissemination

BACKGROUND

Peritoneal metastasis from appendiceal neoplasms is a rare disease usually found unexpectedly and is associated with deficits in quality reporting of findings.

METHODS

Retrospective review of our appendiceal peritoneal metastases carcinomatosis database evaluating quality of index operative and pathology reports. Operative report quality was graded by 2 standards; general quality, based on Royal College of Surgeons quality metrics and peritoneal metastases assessment. Pathology report quality was assessed by the accuracy of diagnosis.

RESULTS

Three hundred and seventy-five index operative reports and 490 outside pathology reports were reviewed. General quality of the index operative reports was excellent, with nearly 80% of reports encompassing all the Royal College of Surgeons quality metrics. Peritoneal metastases assessment was poor. Forty-four percent of the reports performed no peritoneal evaluation, while 48.3% only involved partial peritoneal evaluation. Only 7.7% of the reports performed a complete evaluation. Of the pathology reports, 48.4% had discrepancies with final pathologic findings. Low-grade disease and high-grade disease were misdiagnosed 36.06% and 62.7% of the time, respectively. Discordant treatment occurred in 15.3% and 30.0% of cases for misdiagnosed low-grade and high-grade disease, respectively. Incomplete cytoreduction was attempted in nearly a third of referral cases, which was associated with a significantly increased risk for ultimate incomplete cytoreduction with an odds ratio of 4.72.

CONCLUSION

This review finds that referral operative reports' descriptions of the technical aspects of a procedure is usually complete. However, oncologic parameters and descriptions of peritoneal metastases are frequently incomplete. Further, pathology reports from outside institutions can lead to inappropriate clinical management decisions. We propose a simplified algorithm to assist nonperitoneal surface malignancy surgeons.

A case report of appendix mucinous adenocarcinoma that recurred after additional surgery and a brief literature review

BACKGROUND

The clinical incidence of appendiceal mucinous adenocarcinoma is low. Moreover, the case reports of postoperative relapse after surgery are rarely based on literature search results. Here, we report such a case spanning nearly 7 years and and review the relevant literature.

CASE PRESENTATION

A 50-year-old female underwent additional surgery after appendectomy, and pathological examination confirmed mucinous adenocarcinoma. The patients underwent HIPEC (hyperthermic intraoperative chemotherapy) and adjuvant chemotherapy. Twenty-six months after the previous surgeries, another surgery, HIPEC, and adjuvant chemotherapy were performed again due to tumour recurrence. To date, the follow-up time is 43 months, and no recurrence or metastasis has been found.

CONCLUSIONS

Appendix mucinous adenocarcinoma has a poor prognosis and the diagnosis depends on pathological and immunohistochemical examinations. Its clinical manifestations are non-specific, and CRS + HIPEC should be used for treatment, which is safe and effective.

Impact of adjuvant chemotherapy on outcomes in appendiceal cancer

BACKGROUND

The impact of using adjuvant chemotherapy following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with appendiceal adenocarcinoma is not known. The aim of this study was to assess the impact of adjuvant chemotherapy following complete cytoreduction in patients with appendiceal adenocarcinoma.

METHODS

Retrospective medical record review of all patients with appendiceal adenocarcinoma treated at our institution between 2006 and 2015. Kaplan-Meier plots were used to summarize overall survival (OS) and relapse-free survival over time, and log-rank tests and Cox proportional hazards models were used to test for differences in survival between groups.

RESULTS

A total of 103 patients with appendiceal adenocarcinoma received care at our institution during the study period. Complete cytoreduction (cytoreductive score 0-1) was achieved in 68 patients (66%). Of these 68 patients, 26 received adjuvant chemotherapy. The most common regimens were capecitabine (n = 11), capecitabine plus oxaliplatin (n = 7), and 5-FU plus oxaliplatin (n = 6). Tumor histopathology and grade, and the ability to achieve complete cytoreduction were significant predictors of overall survival. The median OS for non-low-grade and well-differentiated tumor patients who received adjuvant chemotherapy following complete cytoreduction was 9.03 years, compared to 2.88 years for patients who did not receive adjuvant chemotherapy (P = .02). Among low-grade and well-differentiated tumor patients who underwent complete cytoreduction, there was no statistically significant difference in OS between those who received adjuvant chemotherapy and those who did not.

CONCLUSION

Adjuvant chemotherapy seems to have benefit in appendiceal cancer patients with non-low-grade or well-differentiated tumor type but not in low-grade or well-differentiated tumors.

The Chicago Consensus on peritoneal surface malignancies: Management of appendiceal neoplasms

The Chicago Consensus Working Group provides multidisciplinary recommendations for the management of appendiceal neoplasms specifically related to the management of peritoneal surface malignancies. These guidelines are developed with input from leading experts, including surgical oncologists, medical oncologists, pathologists, radiologists, palliative care physicians, and pharmacists. These guidelines recognize and address the emerging need for increased awareness in the appropriate management of peritoneal surface disease. They are not intended to replace the quest for higher levels of evidence.

The Chicago Consensus on Peritoneal Surface Malignancies: Management of Appendiceal Neoplasms

The Chicago Consensus Working Group provides multidisciplinary recommendations for the management of appendiceal neoplasms specifically related to the management of peritoneal surface malignancies. These guidelines are developed with input from leading experts including surgical oncologists, medical oncologists, pathologists, radiologists, palliative care physicians, and pharmacists. These guidelines recognize and address the emerging need for increased awareness in the appropriate management of peritoneal surface disease. They are not intended to replace the quest for higher levels of evidence.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Should We Be Doing Cytoreductive Surgery with HIPEC for Signet Ring Cell Appendiceal Adenocarcinoma? A Study from the US HIPEC Collaborative

BACKGROUND

Appendiceal adenocarcinoma with signet ring cells (SCA) is associated with worse overall survival (OS), and it is unclear whether cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) should be pursued in this patient population. We assessed the prognostic implications of signet ring cells in patients with appendiceal adenocarcinoma and peritoneal carcinomatosis undergoing CRS-HIPEC.

METHODS

The US HIPEC Collaborative, a 12-center, multi-institutional database of patients undergoing CRS-HIPEC, was reviewed for patients with SCA. Univariate and multivariate analyses were performed.

RESULTS

Of 514 patients undergoing CRS-HIPEC for appendiceal adenocarcinoma, 125 (24%) had SCA. The SCA and non-SCA groups had similar baseline characteristics. SCA had worse OS compared with non-SCA (32.0 vs 91.4 months, p < 0.001). In univariate analysis for only SCA cases, there was worse OS in patients with poorly differentiated tumors, positive lymph nodes, LVI, PCI > 20, or incomplete cytoreduction (CC-2/3). However, multivariate analysis showed only positive lymph nodes (HR 1.14 [95% CI 1.00-1.31], p = 0.04), poor differentiation (5.60 [1.29-24.39], p = 0.02), and incomplete cytoreduction (4.90 [1.11-12.70], p = 0.03) were independently associated with decreased OS for SCA.

CONCLUSION

While signet cells are a negative prognostic feature, they should not be a contraindication to CRS-HIPEC in patients with well-moderately differentiated tumors with negative lymph nodes, where complete cytoreduction can be achieved.

Giant low-grade appendiceal mucinous neoplasm: A case report

BACKGROUND

Appendiceal mucinous neoplasm (AMN) is extremely rare. Since the disease does not manifest a characteristic profile of clinical symptoms, it is easy to misdiagnose and still difficult to diagnose without operation. Here, we report a case of low-grade AMN (LAMN) and summarize its clinical features, diagnosis, and treatment.

CASE SUMMARY

A 63-year-old postmenopausal woman presented with a history of right lower abdominal mass. The patient underwent laparotomy, which showed an appendiceal mucocele originating from the apex of the appendix, and a simple appendectomy was performed. The subsequent histological assessment identified an LAMN with no lymph node involvement and negative surgical margin. The patient received six cycles of chemotherapy after surgery, and to date, more than a year after the surgery, the patient remains in good health.

CONCLUSION

A unified, standardized, detailed, and accurate pathological diagnosis is needed for LAMN, to facilitate selection of an appropriate surgical plan. In addition, the surgeon should record the details of the tumors in the surgical records in order to facilitate follow-up after surgery.

Systemic chemotherapy before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in patients with high-grade mucinous carcinoma peritonei of appendiceal origin

BACKGROUND

The role of systemic chemotherapy (SC) before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in appendiceal high-grade mucinous carcinoma peritonei (HGMCP) is controversial. We analyzed the effect of SC prior to CRS/HIPEC in HGMCP.

METHODS

A prospective database of CRS/HIPEC procedures for HGMCP without signet ring cells and with signet ring cells (HGMCP-S) from 1998 to 2017 was reviewed. Exclusion criteria was prior surgery >5 regions or >2 regimens of prior SC. Perioperative variables were analyzed.

RESULTS

There were 140 HGMCP/HGMCP-S identified: 64 with prior SC (preSC) and 76 without (noSC). Groups were balanced for lymph node status, complete cytoreduction rate, disease burden, complications, and postoperative SC. PreSC had more HGMCP-S, moderately/poorly differentiated histology, and longer time-to-surgery (median: 6 vs 2 months, p < 0.001). Median overall survival (mOS) was 40 vs 86 and median progression-free survival (mPFS) was 19 vs 43 months for preSC vs noSC, respectively (p = 0.006 and p = 0.007). In HGMCP-S subanalysis, mOS was 25 vs 39 and mPFS 16 vs 29 months for preSC vs noSC, respectively (p = 0.188 and p = 0.063). In moderately/poorly differentiated histology subanalysis, mOS was 38 vs 56 and mPFS 18 vs 29 months in preSC vs noSC, respectively (p = 0.199 and 0.082). Prior SC was not linked to improved OS or PFS in non-signet ring HGMCP or well-differentiated histology subanalysis.

CONCLUSION

Prior SC was not associated with less disease burden, better cytoreduction rates, or improved clinical outcomes in HGMCP, regardless of histopathologic subtype. Traditional SC agents may not be effective in HGMCP in the neoadjuvant setting.

Low-grade Appendiceal Mucinous Neoplasm Presenting as Adnexal Mass: A Case Report

An appendiceal mucocele is a dilatation of the appendix and it is the result of benign or malignant diseases, which cause the obstruction of the appendix and the consequent accumulation of mucus secretion. The preoperative diagnosis is difficult due to non-specific clinical manifestations of the disease. We present a case of an 83-year-old female patient with a history of breast cancer that was referred to our hospital for an evaluation of a right adnexal mass discovered during her yearly follow-up. The patient underwent an exploratory laparotomy with a provisional diagnosis of a right adnexal mass. A perioperative, appendiceal mucocele was diagnosed. She underwent a formal appendectomy and histopathology of the specimen revealed a low-grade mucinous neoplasm. Appendiceal mucinous neoplasms represent a rare form of pathology among all appendectomy specimens. A preoperative diagnosis is difficult due to the lack of specific symptoms and it is often misdiagnosed as an adnexal mass. The perforation of the appendix and subsequent extravasation of its contents into the abdominal cavity may lead to pseudomyxoma peritonei, which has a very poor prognosis if not treated properly.

Hyperthermic Intraperitoneal Chemotherapy and Cytoreductive Surgery in the Management of Peritoneal Carcinomatosis

BACKGROUND

Malignant peritoneal disease can lead to significant debility due to bowel obstructions, ascites, and cancer cachexia. Moreover, inadequate imaging techniques can lead to the suboptimal detection of disease, and the poor vascularity of tumors can lead to a poor response to systemic chemotherapy. However, combination cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (HIPEC) is a promising novel treatment for patients with this disease.

METHODS

The medical literature focusing on diagnostic updates and the management of peritoneal disease was reviewed. The application principles of HIPEC for use in peritoneal disease were also summarized.

RESULTS

Improvements in imaging and the application of laparoscopic techniques have significantly increased the rate of diagnosis of early peritoneal disease with consequently less morbid cytoreductive procedures. Appropriate patient selection based on prognostic scores along with complete cytoreduction can identify a cohort of patients likely to derive durable benefit from this combination treatment.

CONCLUSIONS

Advances in diagnostic and therapeutic techniques, including surgical cytoreductive techniques, have demonstrated significant survival gains in patients with peritoneal disease. Although HIPEC can be used for the management of various types of histologies, further development of high-level evidence is necessary to advance the field.

Treatment of peritoneal surface malignancies with hyperthermic intraperitoneal chemotherapy-current perspectives

Peritoneal carcinomatosis (ptc) represents advanced malignant disease and has generally been associated with a grim prognosis. Peritoneal surface malignancy is often the major source of morbidity and mortality; it is of major concern in cancer management. Although ptc is categorized as metastatic disease, it represents a special disease pattern considered to be a locoregional disease limited to the abdominal cavity. The combination of cytoreductive surgery (crs) and intraoperative hyperthermic intraperitoneal chemotherapy (hipec) has successfully been used as locoregional treatment for selected patients with ptc from gastric, colorectal, and ovarian cancer; with mesothelioma; and with pseudomyxoma peritonei. In the prophylactic setting, hipec can also be used to prevent ptc in high-risk patients, and the first results of the "second-look" approach are promising. Patient selection-in which the risks of perioperative morbidity and mortality, which are analogous to those for any other major gastrointestinal surgery, are assessed-is of utmost importance. Those risks have to be weighed against the anticipated survival benefit, which depends mainly on tumour biology, extent of disease, and probability of achieving complete crs. The present review discusses the principles of crs and hipec, the most significant recent clinical data, and current perspectives concerning the application of this treatment modality in various malignancies. Ongoing trials and future directions are noted. It appears that the combination of crs and hipec is an indispensable tool in the oncologist's armamentarium.

Diagnosis and Treatment of Mucinous Appendiceal Neoplasm Presented as Acute Appendicitis

Appendiceal mucocele is a rare cause of acute abdomen. Mucinous appendiceal neoplasms represent 0.2-0.7% of all appendix specimens. The aim of this study is to report a case of a mucinous appendiceal neoplasm presented as acute appendicitis, discussing the clinical and surgical approach in the emergency setting. A 72-year-old female patient was admitted to the emergency department with a clinical examination indicative of acute abdomen. The patient underwent abdominal computed tomography scan which revealed a cystic lesion in the right iliac fossa measuring 8.3 × 5.2 × 4.1 cm, with calcified walls, and a mean density indicative of high protein content. The patient was taken to the operating room and a right hemicolectomy was performed. The postoperative course was unremarkable. The histopathological examination revealed a low-grade mucinous appendiceal neoplasm with negative regional lymph nodes. Ultrasound and CT are useful in diagnosing appendiceal mucocele and synchronous cancers in the emergency setting. The initial operation should include appendectomy and resection of the appendicular mesenteric fat along with any fluid collection for cytologic examination. During urgent appendectomy it is important to consider every mucocele as malignant in order to avoid iatrogenic perforation causing pseudomyxoma peritonei. Although laparotomy is recommended, the laparoscopic approach is not contraindicated.