The Pathologic Peritoneal Cancer Index (PCI) Strongly Differs From the Surgical PCI in Peritoneal Metastases Arising From Various Primary Tumors

Overall survival and prognostic factors associated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy combined with intraoperative radiation therapy in patients with advanced abdominopelvic malignancies: A single center retrospective analysis of 159 patients

BACKGROUND AND OBJECTIVES

The aim of this study was to look at the overall survival (OS), progression-free survival (PFS), and prognostic factors associated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) combined with intraoperative radiation therapy (IORT).

METHODS

This study is a single center retrospective study performed on 159 patients who underwent treatment with CRS and HIPEC combined with IORT for abdominopelvic malignancies. OS and PFS were used to evaluate the efficacy of this treatment strategy amongst patients with abdominopelvic malignancies.

RESULTS

The cohort's median age was 53 years, with a male predominance (58.5%). The median OS was not reached, but the mean OS was 76.87 months. In univariate analysis, several factors, including synchronous organ metastasis, Pathologic Peritoneal Carcinomatosis Index (pPCI) ≥10, increased estimated blood loss, and severe postoperative complications, were associated with worse OS. However, multivariate analysis identified pPCI ≥ 10 as the sole independent predictor of worse OS. The 1- and 3-year survival rates were 83% and 70.4%, respectively. pPCI ≥ 10 and severe postoperative complications were significant predictors of worse survival outcomes.

CONCLUSIONS

Radical surgery alone is not enough, and CRS combined with HIPEC and IORT, when indicated, was proven to be safe and effective with no added morbidity or mortality.

Assessment of Intraoperative Scoring Systems for Predicting Cytoreduction Outcome in Peritoneal Metastatic Disease: A Systematic Review and Meta-analysis

BACKGROUND

Cytoreductive surgery (CRS) is a widely acknowledged treatment approach for peritoneal metastasis, showing favorable prognosis and long-term survival. Intraoperative scoring systems quantify tumoral burden before CRS and may predict complete cytoreduction (CC). This study reviews the intraoperative scoring systems for predicting CC and optimal cytoreduction (OC) and evaluates the predictive performance of the Peritoneal Cancer Index (PCI) and Predictive Index Value (PIV).

METHODS

Systematic searches were conducted in Embase, MEDLINE, and Web of Science. Meta-analyses of extracted data were performed to compare the absolute predictive performances of PCI and PIV.

RESULTS

Thirty-eight studies (5834 patients) focusing on gynecological (n = 34; 89.5%), gastrointestinal (n = 2; 5.3%) malignancies, and on tumors of various origins (n = 2; 5.3%) were identified. Seventy-seven models assessing the predictive performance of scoring systems (54 for CC and 23 for OC) were identified with PCI (n = 39/77) and PIV (n = 16/77) being the most common. Twenty models (26.0%) reinterpreted previous scoring systems of which ten (13%) used a modified version of PIV (reclassification). Meta-analyses of models predicting CC based on PCI (n = 21) and PIV (n = 8) provided an AUC estimate of 0.83 (95% confidence interval [CI] 0.79-0.86; Q = 119.6, p = 0.0001; I2 = 74.1%) and 0.74 (95% CI 0.68-0.81; Q = 7.2, p = 0.41; I2 = 11.0%), respectively.

CONCLUSIONS

Peritoneal Cancer Index models demonstrate an excellent estimate of CC, while PIV shows an acceptable performance. There is a need for high-quality studies to address management differences, establish standardized cutoff values, and focus on non-gynecological malignancies.

Preoperative [18F]fluoro-PEG-folate PET/CT in advanced stage epithelial ovarian cancer: A safety and feasibility study

PURPOSE

The selection for either primary or interval cytoreductive surgery (CRS) in patients with epithelial ovarian cancer (EOC) is currently based on imaging techniques like computed tomography (CT), [18F]fluorodeoxyglucose-positron emission tomography ([18F]FDG-PET), diffusion-weighted magnetic resonance imaging (DW-MRI) and/or diagnostic laparoscopy, but these have limitations. Folate receptor (FR)-targeted PET/CT imaging, using [18F]fluoro-PEG-folate, could improve preoperative assessment, potentially reducing unnecessary laparotomies. This paper presents the first experience with [18F]fluoro-PEG-folate PET/CT imaging in advanced stage EOC, focusing on safety, tolerability, and feasibility for reflecting the extent of disease.

METHODS

Tolerability and safety were monitored after administration of the [18F]fluoro-PEG-folate tracer by measurements of vital function parameters (blood pressure, heart rate, peripheral oxygen saturation, respiratory rate, and temperature). In addition, (serious) adverse events were recorded. Disease burden was quantified using the Peritoneal Cancer Index (PCI) score on preoperative [18F]fluoro-PEG-folate PET/CT and during surgery. PCI scores were compared with intraoperative findings, considering histopathologic results as the gold standard. Tissue specimens were stained for FRα and FRβ. Relative uptake of the radiotracer by EOC lesions and other tissues was quantified using body weighted standardized uptake values (SUV).

RESULTS

The study was terminated prematurely during the interim analysis after inclusion of eight patients of whom five had completed the study protocol. Although [18F]fluoro-PEG-folate demonstrated safety, efficacy for tumor-specific imaging was limited. Despite clear FRα overexpression, low tracer uptake was observed in EOC lesions, contrasting with high uptake in healthy tissues, posing challenges in specificity and accurately assessing tumor burden.

CONCLUSIONS

Overall, while [18F]fluoro-PEG-folate was well-tolerated, its clinical utility in the preoperative assessment of the extent of disease in EOC was limited. This highlights the need for further research in developing targeted imaging agents for optimal detection of EOC metastases.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT05215496. Registered 31 January 2022.

The Significance of the Morphological Appearance of Peritoneal Lesions on Imaging in Patients With Peritoneal Malignancies-A Report From Phase 1 of the PRECINCT Study

BACKGROUND AND AIM

This is a report from Phase 1 of the prospective, observational, PRECINCT (Pattern of peritoneal dissemination and REsponse to systemic Chemotherapy IN Common and uncommon peritoneal Tumours) study, in which we studied the incidence of disease at pathological evaluation in different morphological appearances of peritoneal malignancies (PM) on imaging.

METHODS

Radiological findings were captured in a specific format that included a description of the morphological appearance of PM and a correlation performed with pathological findings.

RESULTS

In 630 patients enroled at seven centres (September 2022-December 2023), 24 morphological terms were used. Among prespecified terms (N = 8 used in 6350 [92.2%] regions), scalloping was pathologically positive in 93.5%, confluent disease in 78.8%, tumour nodules in 69.6%, thickening in 66.1%, infiltration in 56.3%. Among unspecified appearances (N = 16) for 540 (7.8%) regions, 'enhancement' was positive in 41.5%, micronodules in 65.3% and nodularity in 60.2%. Hierarchal clustering placed gastric cancer and rare tumours together and colorectal cancer, ovarian cancer and peritoneal mesothelioma in one cluster.

CONCLUSIONS

The incidence of disease at pathological evaluation for most morphological appearances was high (> 50%). Morphological description should be provided in routine radiology reports. A set of standardized terms with their description should be developed by a consensus among experienced radiologists.

Impact of Previous Abdominal Surgery and Timing of Peritoneal Metastases on Accuracy of Imaging in Predicting the Surgical PCI: A Report From the PRECINCT Study

BACKGROUND AND AIM

In this report from Phase 1 of the prospective, observational, PRECINCT (Pattern of peritoneal dissemination and REsponse to systemic Chemotherapy IN Common and uncommon peritoneal Tumours) study, a correlation was performed between the radiological PCI (peritoneal cancer index; rPCI) and surgical PCI (sPCI). The impact of timing of peritoneal malignancy (PM) and previous abdominal surgery was also studied.

METHODS

The rPCI and sPCI were considered the 'same' if they differed by ≤ 3 points. The agreement was assessed using Bland-Altman analysis and the strength of the agreement was assessed using the concordance correlation coefficient (CCC). The extent of prior surgery was classified according to prior surgical score (PSS).

RESULTS

In 707 (79.4%) patients, rPCI and sPCI concurred in 280 (39.6%). In the Bland-Altman analysis, < 40% patients were in the ±3 PCI points limit of acceptable difference. The average difference between the two scores was 4.5 points (95% CI- -5.16 to -3.92). The CCC- was 0.59 for the whole cohort ('moderate' concordance) and was not influenced by imaging modality, timing of PM or PSS.

CONCLUSIONS

The rPCI underestimated sPCI by an average of 4.5 points. The role of peritoneal MRI in patients undergoing iterative procedures and the performance of imaging according to sites of recurrence need further evaluation.

Correlation of Morphological Appearance of Peritoneal Lesions at Laparotomy and Disease at Pathological Assessment in Patients Undergoing Cytoreductive Surgery for Peritoneal Malignancy: Results of Phase I of the PRECINCT Study in 707 Patients

BACKGROUND

The PRECINCT (Pattern of peritoneal dissemination and REsponse to systemic Chemotherapy IN Common and uncommon peritoneal Tumors) is a prospective, multicenter, observational study. This report from phase I of PRECINCT outlines variations in recording the surgical peritoneal cancer index (sPCI) at experienced peritoneal malignancy centers and the incidence of pathologically confirmed disease in morphologically different peritoneal lesions (PL).

METHODS

The sPCI was recorded in a prespecified format that included the morphological appearance of PL. Six prespecified morphological terms were provided. The surgical and pathological findings were compared.

RESULTS

From September 2020 to December 2021, 707 patients were enrolled at 10 centers. The morphological details are routinely recorded at two centers, structure bearing the largest nodule, and exact size of the largest tumor deposit in each region at four centers each. The most common morphological terms used were normal peritoneum in 3091 (45.3%), tumor nodules in 2607 (38.2%) and confluent disease in 786 (11.5%) regions. The incidence of pathologically confirmed disease was significantly higher in 'tumor nodules' with a lesion score of 2/3 compared with a lesion score of 1 (63.1% vs. 31.5%; p < 0.001). In patients receiving neoadjuvant chemotherapy, the incidence of pathologically confirmed disease did not differ significantly from those undergoing upfront surgery [751 (47.7%) and 532 (51.4%) respectively; p = 0.069].

CONCLUSIONS

The sPCI was recorded with heterogeneity at different centers. The incidence of pathologically confirmed disease was 49.2% in 'tumor nodules'. Frozen section could be used more liberally for these lesions to aid clinical decisions. A large-scale study involving pictorial depiction of different morphological appearances and correlation with pathological findings is indicated.

D, Piplani S. Pathological PCI as a prognostic marker of survival after neoadjuvant chemotherapy in patients undergoing interval cytoreduction with or without HIPEC in FIGO stage IIIC high grade serous ovarian cancer

Objective

To determine the best possible value of pathological PCI (pPCI) as a prognostic marker for survival in high-grade serous epithelial ovarian cancer patients in patients treated with neoadjuvant chemotherapy and interval cytoreductive surgery.

Methods

All patients with FIGO stage IIIC high-grade serous ovarian carcinoma were included. Receiver operating curves (ROC) were used to determine the best possible score for pPCI in predicting survival. Survival curves were calculated using the Kaplan-Meier test, and factors affecting survival were compared using the log-rank test.

Results

From January 2018 to January 2024, 171 patients who underwent interval cytoreductive surgery were included. Complete cytoreduction was achieved in 88% of the patients. ROC curves determined a (pPCI) cut-off value of 8 as the best possible score for predicting survival with a sensitivity of 82% and specificity of 67% (Youden's Index = 0.60). pPCI with a cut-off value of 8 showed improved OS (p = 0.002) and DFS, (p = 0.001) in both univariate and multivariate analyses.

Conclusion

Following interval cytoreductive surgery, despite optimal complete cytoreductive surgery, a pathological PCI of 8 is a poor prognostic indicator of survival and may serve as a surrogate clinical marker for guiding clinicians in adjuvant treatment, especially in resource-driven settings in the real world.

A systematic review of minimally invasive cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with peritoneal malignancy

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is traditionally a maximally invasive operation with a large abdominal incision and multi-visceral resections. However, to minimize abdominal wall morbidity and improve functional recovery, some centres have adopted a minimally invasive (MI) approach in select cases. The primary aim of this systematic review and meta-analysis was to assess the evidence for safety and patient selection for minimally invasive approaches to CRS and HIPEC with curative intent.

METHODS

A PRISMA-compliant systematic review was performed using three electronic databases: Ovid MEDLINE, EMBASE and Web of Science. Data regarding postoperative morbidity was meta-analysed.

RESULTS

Thirteen studies met the inclusion criteria (N = 462 MI patients), all of which were retrospective in design. Six studies included an open comparison group. Pseudomyxoma peritonei, mesothelioma and ovarian carcinoma made up the majority of cases (>90%), with a PCI < 10 listed as a prerequisite to selection across all studies. On pooled analysis there was no difference in major morbidity between MI and open groups (OR 0.52 95% CI 0.18-1.46, P = 0.33). There was one perioperative death reported in the MI group. Length of stay appeared shorter in the MI group (median range MI: 4-11 v Open: 7-13 days). Short-term recurrence and overall survival between both groups also appeared no different.

CONCLUSION

Minimally invasive CRS and HIPEC appears feasible and safe in appropriately selected patients. Clear histological stratification and longer term follow up is required to determine oncological safety, particularly in more aggressive tumours such as colorectal peritoneal metastases.

Critical reappraisal of prognostic indicators for 949 mucinous appendiceal neoplasm patients

BACKGROUND AND OBJECTIVES

The standard of care for treatment of an appendiceal mucinous neoplasm with peritoneal dissemination is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). These two treatments are combined in the operating room. A crucial requirement for benefit long-term is proper patient selection. Clinical and histopathologic prognostic indicators are used, along with the patient's fitness for surgery, to select patients to receive CRS and HIPEC.

METHODS

This study seeks to identify the reliable prognostic indicators for four different groups of patients. They are (1) the low-grade appendiceal mucinous neoplasms (LAMN) with a complete CRS, (2) the mucinous appendiceal adenocarcinomas (MACA) with complete CRS, (3) MACA with lymph node metastases (MACA-LN) with complete CRS, and (4) all histologic subtypes with incomplete cytoreduction. The prognostic indicators were evaluated for their impact on overall survival in these four groups of patients.

RESULTS

The completeness of cytoreduction (CC) score statistically significantly showed survival differences in all three histologic subtypes. The peritoneal cancer index (PCI) showed significance with LAMN and MACA-LN but not with MACA and not with incomplete CRS. The prior surgical score (PSS) was a prognostic indicator that predicted the outcome with LAMN, MACA-LN, and incomplete CRS patients but not with the MACA group. Patients who were symptomatic or who had extensive systemic chemotherapy before CRS had a significantly reduced survival.

CONCLUSION

The utility of prognostic indicators varied greatly within our four different groups of appendiceal mucinous neoplasms. CC score was always a reliable prognosticator. Surprisingly, PCI was not.

Cytoreductive Surgery with Bidirectional Intraoperative Chemotherapy (BDIC) Using Intravenous Ifosfamide Plus Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Patients with Peritoneal Sarcomatosis: A Retrospective Cohort Study

BACKGROUND

Peritoneal sarcomatosis (PS) is a rare tumor with limited therapeutic options. Bidirectional intraoperative chemotherapy (BDIC) using intravenous ifosfamide and doxorubicin-based hyperthermic intraperitoneal chemotherapy (HIPEC) after cytoreductive surgery (CRS) is an emerging treatment for peritoneal malignancies.

PATIENTS AND METHODS

Patients with PS who underwent CRS/BDIC using intravenous ifosfamide and HIPEC from January 2017 to July 2021 were retrospectively analyzed. The last follow-up date was May 2022.

RESULTS

A total of 29 patients were included. Overall survival (OS) rates at 6, 12, 24, and 48 months after CRS/BDIC were 93.1%, 89.2%, 81.4%, and 73.3%, respectively. As of May 2022, 6 patients (20.6%) had died, including four (13.8%) with a proven recurrent tumor and two with incomplete tumor resection [completeness of cytoreduction (CC)-2 or CC-3]. Of the 20 patients (68.9%) with CC-0 or CC-1, 7 had locoregional tumor recurrence without distant metastasis, whereas the other 13 were alive with no evidence of recurrent tumor in May 2022. Disease recurrence rates were 15% at 6 months and 35% at 12, 24, and 48 months after CRS/BDIC. Clavien-Dindo class ≥ IIIa complications developed in 9 patients (31.0%) with no deaths. Leukopenia occurred in 5 patients (17.2%) and thrombocytopenia in 12 patients (41.3%); these hematologic abnormalities resolved. A total of 9 (31.0%) patients developed nephrotoxicity; all recovered except one, who progressed to chronic kidney disease.

CONCLUSIONS

CRS/BDIC using intravenous ifosfamide and doxorubicin-based HIPEC is a potentially effective treatment for PS and has an acceptable rate of complications.

Use of early postoperative intraperitoneal 5-fluorouracil with index cytoreduction improves survival with secondary cytoreductive surgery

BACKGROUND

In patients with appendiceal mucinous neoplasm with peritoneal dissemination, a cytoreductive surgery (CRS) with perioperative chemotherapy may result in long-term survival. Disease progression may require secondary cytoreductive surgery (SCRS) and other treatments in selected patients to improve survival and preserve an optimal quality of life.

METHODS

The clinical- and treatment-related variables associated with the index CRS and SCRS were statistically assessed for impact on survival after SCRS.

RESULTS

A total of 186 of 687 complete CRS patients (27.1%) had SCRS. Median follow-up was 10 years and median survival was 12 years. In 95 males (51%) the median age was 45.0 years. Survival benefit with SCRS was observed if early postoperative intraperitoneal chemotherapy (EPIC) with 5-fluorouracil (EPIC 5-FU) or hyperthermic intraperitoneal chemotherapy (HIPEC) plus EPIC 5-FU was used with the index CRS (hazard ratio [HR]: 0.6, p = 0.0360; HR: 0.4, p = 0.0004, respectively). By propensity matching of 51 pairs of patients, EPIC 5-FU used with index CRS caused a survival advantage compared to HIPEC alone (p = 0.0100) with index CRS (p = 0.0100).

CONCLUSIONS

Use of EPIC 5-FU at a complete index CRS was a prognostic variable that improved survival in patients requiring SCRS. Further investigations into the benefits of antiadhesion treatments with CRS and HIPEC are warranted.

Clinical and Histopathologic Features of 35 Patients Treated for Colorectal Peritoneal Metastases Who Survived 5 Years

BACKGROUND

Currently, patients with a limited extent of peritoneal metastases from colon and rectal cancer are treated by cytoreductive surgery combined with perioperative chemotherapy performed at experienced centers.

OBJECTIVE

To statistically evaluate features that may impact survival of ≥5 years. These data are used in the risk/benefit analyses performed by the multidisciplinary team.

DESIGN

This was a retrospective review of a prospective database.

SETTINGS

This single-institution study was conducted at an academic center.

PATIENTS

All patients who had biopsy-proven colon or rectal peritoneal metastases treated by systemic chemotherapy, complete cytoreductive surgery, and perioperative surgery were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were the clinical-, histologic-, and treatment-related features that had an impact on 5-year survival.

RESULTS

From 131 patients who had complete cytoreduction, 35 patients (26.7%) were identified as 5-year survivors. The median survival time was 27 months. The median age was 50.5 (range, 25-80) years. By univariant analysis, an absence of lymph node involvement at the time of primary colorectal cancer resection (HR 1.899 [95% CI, 1.064-3.388]; p = 0.03), complete or near-complete response to neoadjuvant chemotherapy (HR 0.251 [95% CI, 0.092-0.684]; p = 0.007), peritoneal cancer index ≤17 (HR 0.509 [95% CI, 0.329-0.788]; p = 0.002), complete visible resection of disease indicated by the completeness of cytoreduction score of 0 (HR 0.412 [95% CI, 0.224-0.756]; p = 0.004), and well-differentiated tumor (HR 0.34 [95% CI, 0.157-0.737]; p = 0.006) were significantly associated with ≥5 years survival.

LIMITATIONS

Limitations include its retrospective nature, unmeasured confounders, and data from a single institution.

CONCLUSIONS

The tumor biology as revealed by lymph node status and tumor differentiation plus extent of disease as measured by the response to neoadjuvant chemotherapy, peritoneal cancer index, and no visible residual disease indicated a favorable outcome. See Video Abstract at http://links.lww.com/DCR/C62 .

CARACTERSTICAS CLNICAS E HISTOPATOLGICAS EN PACIENTES TRATADOS POR METASTASIS PERITONEALES DE ORGEN COLORECTAL Y QUE SOBREVIVIERON AOS

ANTECEDENTES:Actualmente, los pacientes con extensión limitada de metástasis peritoneales de orígen colorectal son tratados mediante cirugía citorreductora asociada con una quimioterapia peri-peratoria realizadas en centros experimentados.OBJETIVO:Estúdio y evaluación estadística de las características que puedan impactar en la sobrevida de los pacientes a 5 años o más. Se utilizaron estos datos en el análisis de riesgo /beneficio realizados por un equipo multidisciplinario.DISEÑO:Revisión retrospectiva de una base de datos prospectiva.AJUSTES:Estudio realizado en una sola institución académica.PACIENTES:Todos aquellos que presentaban metástasis peritoneales de orígen colorectal, comprobadas por biopsia y tratadas con quimioterapia sistémica, cirugía peri-operatoria y citorreductora completas.MEDIDAS DE RESULTADO PRINCIPALES:Las medidads de resultados primarios fueron las características clínicas, histológicas y relacionadas con el tratamiento que tuvieron un impacto en la sobrevida a 5 años.RESULTADOS:De 131 pacientes que tuvieron una cirugía de citorreducción completa, 35 pacientes (26, 7%) fueron identificados como sobrevivientes a 5 años. La mediana de sobrevida fué de 27 meses. Se identificarion 16 varones. La mediana de edad fue de 50, 5 años con un rango de 25 a 80 años. Según análisis univariante, la ausencia de compromiso de los ganglios linfáticos en el momento de la resección del cáncer colorrectal primario (HR 1,899 (1,064, 3,388) p = 0,03), la respuesta completa o casi completa al tratamiento neoadyuvante con quimioterapia (HR 0,251 (0,092, 0,684) p = 0,007), el índice de cáncer peritoneal ≤17 (HR 0,509 (0,329, 0,788) p = 0,002), la resección completa y visible de la enfermedad indicada por la puntuación de citorreducción de 0 (HR 0,412 (0,224), 0,756) p = 0,004) y los tumores bien diferenciados (HR 0,34 (0,157, 0,737) p = 0,006) se asociaron significativamente con 5 o más años de sobrevida.LIMITACIONES:El estudio se encontró limitado por su naturaleza retrospectiva, por la no medida de factores de confusión y por los datos provenientes de una sola institución.CONCLUSIONES:La biología tumoral demostrada según el estado de los ganglios linfáticos y la diferenciación tumoral, agregada a la extensión de la enfermedad medida por la respuesta a la quimioterapia neoadyuvante, el índice de cáncer peritoneal y la ausencia visible de enfermedad residual, demostraron un resultado favorable. Consulte Video Resumen en http://links.lww.com/DCR/C62(Traducción-Dr. Xavier Delgadillo ).

Novel Multi-Modal Therapies and Their Prognostic Potential in Gastric Cancer

BACKGROUND

Gastric cancer has a poor prognosis and involves metastasis to the peritoneum in over 40% of patients. The optimal treatment modalities have not been established for gastric cancer patients with peritoneal carcinomatosis (GC/PC). Although studies have reported favourable prognostic factors, these have yet to be incorporated into treatment guidelines. Hence, our review aims to appraise the latest diagnostic and treatment developments in managing GC/PC.

METHODS

A systematic review of the literature was performed using MEDLINE, EMBASE, the Cochrane Review, and Scopus databases. Articles were evaluated for the use of hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurised intraperitoneal aerosolised chemotherapy (PIPAC) in GC/PC. A meta-analysis of studies reporting on overall survival (OS) in HIPEC and comparing the extent of cytoreduction as a prognostic factor was also carried out.

RESULTS

The database search yielded a total of 2297 studies. Seventeen studies were included in the qualitative and quantitative analyses. Eight studies reported the short-term OS at 1 year as the primary outcome measure, and our analysis showed a significantly higher OS for the HIPEC/CRS cohort compared to the CRS cohort (pooled OR = 0.53; p = 0.0005). This effect persisted longer term at five years as well (pooled OR = 0.52; p < 0.0001). HIPEC and CRS also showed a longer median OS compared to CRS (pooled SMD = 0.61; p < 0.00001). Three studies reporting on PIPAC demonstrated a pooled OS of 10.3 (2.2) months. Prognostic factors for longer OS include a more complete cytoreduction (pooled OR = 5.35; p < 0.00001), which correlated with a peritoneal carcinomatosis index below 7.

CONCLUSIONS

Novel treatment strategies, such as HIPEC and PIPAC, are promising in the management of GC/PC. Further work is necessary to define their role within the treatment algorithm and identify relevant prognostic factors that will assist patient selection.

Palliation of mucinous appendiceal neoplasms with peritoneal metastases with total abdominal colectomy

BACKGROUND

Incomplete cytoreduction for mucinous appendiceal neoplasms is often required to temporarily alleviate symptoms. The surgical technology for this intervention may be complex and result in extensive morbidity and even mortality. Knowledgeable patient selection for this surgery is mandatory.

METHODS

A database was used to identify patients who had palliative surgery that included total abdominal colectomy (TAC). Clinical- and treatment-related variables were assessed for their impact on overall survival.

RESULTS

Seventy-eight patients had an incomplete cytoreductive surgery (CRS) that included a TAC. The median survival was 2.5 years and the median follow-up was 2 years. Patients with symptoms of abdominal distention and ascites showed a reduced prognosis (p = 0.0254). The low-grade appendiceal mucinous neoplasms (LAMN) and mucinous appendiceal adenocarcinoma intermediate type (MACA-Int) grouped together showed a prolonged survival (p = 0.0003). MACA with positive lymph nodes showed a reduced survival (p = 0.0009) when compared to MACA patients without positive lymph nodes. A peritoneal cancer index of 1-30 versus >30 and completeness of cytoreduction score of 2 versus 3 were not significant.

CONCLUSION

TAC with end ileostomy was used as a treatment option to provide palliation of patients having an incomplete CRS for appendiceal mucinous neoplasms. With LAMN or MACA-Int, median survival was 5.0 years. The surgery can be performed with a morbidity of 9.0% and mortality of 2.6%. Although not considered a palliative option in the past, these data suggest TAC may be used with acceptable results in this group of patients.

Total abdominal colectomy to facilitate complete cytoreduction in 56 patients with mucinous appendiceal neoplasms with peritoneal metastases

BACKGROUND

Cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy are currently the standard of care for management of appendiceal mucinous neoplasms with peritoneal metastases. The goal of the CRS is complete removal of all visible disease through the use of peritonectomy procedures and visceral resections. One of the major resections that may be required is total abdominal colectomy (TAC).

METHODS

From a database and secured files of patients having a complete CRS, all patients who had TAC were identified. The clinical and histologic variables associated with these patients were identified and assessed for their impact on overall survival.

RESULTS

The 450 complete CRS with low-grade appendiceal mucinous neoplasms had 26 TAC (5.8%) with a 16.0-year median survival. The mucinous adenocarcinoma (MACA)-Intermediate (MACA-Int) group consisted of 37 patients with 8 patients (21.6%) having TAC that resulted in a median survival of 11.5 years. The 159 complete CRS with MACA had 22 TAC (13.8%) with a median survival of 7.5 years. There was a single mortality with a class 4 adverse event in 5 patients (10.7%). With a class 4 adverse event, survival decreased significantly (p = 0.0006, hazard ratio: 6.2).

CONCLUSION

Complete CRS required TAC in 56 of 646 patients (8.7%) with appendiceal mucinous neoplasms. With TAC, median survival was 12.0 years. A class 4 adverse event markedly reduced survival.

Response Evaluation in Patients with Peritoneal Metastasis Treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC)

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) directed therapy emerged as a treatment of peritoneal metastasis (PM) a decade ago. The response assessment of PIPAC is not uniform. This narrative review describes non-invasive and invasive methods for response evaluation of PIPAC and summarizes their current status. PubMed and clinicaltrials.gov were searched for eligible publications, and data were reported on an intention-to-treat basis. The peritoneal regression grading score (PRGS) showed a response in 18-58% of patients after two PIPACs. Five studies showed a cytological response in ascites or peritoneal lavage fluid in 6-15% of the patients. The proportion of patients with malignant cytology decreased between the first and third PIPAC. A computed tomography showed stable or regressive disease following PIPAC in 15-78% of patients. The peritoneal cancer index was mainly used as a demographic variable, but prospective studies reported a response to treatment in 57-72% of patients. The role of serum biomarkers of cancer or inflammation in the selection of candidates for and responders to PIPAC is not fully evaluated. In conclusion, response evaluation after PIPAC in patients with PM remains difficult, but PRGS seems to be the most promising response evaluation modality.

Development of the Peritoneal Metastasis: A Review of Back-Grounds, Mechanisms, Treatments and Prospects

Peritoneal metastasis is a malignant disease which originated from several gastrointestinal and gynecological carcinomas and has been leading to a suffering condition in patients for decades. Currently, as people have gradually become more aware of the severity of peritoneal carcinomatosis, new molecular mechanisms for targeting and new treatments have been proposed. However, due to the uncertainty of influencing factors involved and a lack of a standardized procedure for this treatment, as well as a need for more clinical data for specific evaluation, more research is needed, both for preventing and treating. We aim to summarize backgrounds, mechanisms and treatments in this area and conclude limitations or new aspects for treatments.

[Peritoneal carcinomatosis of gastric cancer : Treatment options for peritoneal carcinomatosis of gastric cancer]

BACKGROUND

Gastric cancer is one of the most aggressive malignant diseases of the gastrointestinal tract with a high rate of metastasis. Peritoneal metastasis occurs in up to 60% of all patients and synchronously in up to 30% in locally advanced gastric cancer. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been an established treatment option in selected patients for several years, as the HIPEC serves as an alternative administration route.

OBJECTIVE

This article presents a schematic display of the various treatment options depending on the extent of peritoneal carcinomatosis in a gastric cancer.

METHODS

A literature search and analysis of the current literature on the treatment of gastric cancer with peritoneal metastases were carried out. A differentiation was made between limited and extensive peritoneal carcinomatosis together with the appropriate treatment strategy.

RESULTS

Principally, individual systemic chemotherapy is the backbone of treatment of gastric cancer with peritoneal metastases. In selected patients and in cases of limited peritoneal carcinomatosis, CRS and HIPEC can be conducted and survival is improved; however, CRS is still contraindicated in cases of extensive peritoneal carcinomatosis and in exceptional cases pressurized intraperitoneal aerosol chemotherapy (PIPAC) can be carried out.

CONCLUSION

In selected patients CRS and HIPEC can lead to an improvement with respect to overall and disease-free survival. In cases of extensive peritoneal carcinomatosis, individualized chemotherapy remains the major treatment option.

A practical spatial analysis method for elucidating the biological mechanisms of cancers with abdominal dissemination in vivo

Elucidation of spatial interactions between cancer and host cells is important for the development of new therapies against disseminated cancers. The aim of this study is to establish easy and useful method for elucidating spatial interactions. In this study, we developed a practical spatial analysis method using a gel-based embedding system and applied it to a murine model of cancer dissemination. After euthanization, every abdominal organ enclosed in the peritoneum was extracted en bloc. We injected agarose gel into the peritoneal cavities to preserve the spatial locations of the organs, including their metastatic niches, and then produced specimens when the gel had solidified. Preservation of the original spatial localization was confirmed by correlating magnetic resonance imaging results with the sectioned specimens. We examined the effects of spatial localization on cancer hypoxia using immunohistochemical hypoxia markers. Finally, we identified the mRNA expression of the specimens and demonstrated the applicability of spatial genetic analysis. In conclusion, we established a practical method for the in vivo investigation of spatial location-specific biological mechanisms in disseminated cancers. Our method can elucidate dissemination mechanisms, find therapeutic targets, and evaluate cancer therapeutic effects.

A single-center retrospective cohort study of perioperative systemic chemotherapy in diffuse malignant peritoneal mesothelioma

Background

Diffuse malignant peritoneal mesothelioma (DMPM) is a rare variant of malignant mesothelioma, representing 10–15% of malignant mesothelioma cases. The preferred therapeutic approach is cytoreductive surgery (CRS) accompanied by hyperthermic intraperitoneal chemotherapy (HIPEC); the role of systemic chemotherapy is not well established. While some limited retrospective studies report worse outcomes with neoadjuvant chemotherapy, our institution has favored the use of neoadjuvant chemotherapy for symptom relief and surgical optimization. The aim of our study was to assess the outcomes of patients receiving neoadjuvant chemotherapy, compared to those receiving adjuvant or no perioperative chemotherapy.

Patients and methods

We conducted a single-center retrospective cohort study of treatment-naïve, non-papillary DMPM patients seen at our institution between 1/1/2009 and 9/1/2019. We explored the effect of type of systemic therapy on clinical outcomes and estimated median overall survival (mOS) using Kaplan-Meier curves. Hazard ratios (HR) calculated by Cox proportional hazard model were used to estimate effect of the exposures on overall survival.

Results

47 patients were identified with DMPM (median age at diagnosis 61.2 years, 76.6% epithelioid histology, 74.5% white race, 55.3% known asbestos exposure). CRS was performed in 53.2% of patients (25/47); 76.0% of surgical patients received HIPEC (19/25). The majority received systemic chemotherapy (37/47, 78.7%); among patients receiving both CRS and chemotherapy, neoadjuvant chemotherapy was more common than adjuvant chemotherapy (12 neoadjuvant, 8 adjuvant). Overall mOS was 84.1 months. Among neoadjuvant patients, 10/12 underwent surgery, and 2 were lost to follow-up; the majority (9/10) had clinically stable or improved disease during the pre-operative period. There were numerical more issues with chemotherapy with the adjuvant patients (4/8: 2 switches in platinum agent, 2 patients stopped therapy) than with the neoadjuvant patients (2/10: 1 switch in platinum agent, 1 delay due to peri-procedural symptoms). Neoadjuvant chemotherapy was not associated with worse mOS compared to adjuvant chemotherapy (mOS NR vs 95.1 mo, HR 0.89, 95% CI 0.18–4.5, p = 0.89).

Conclusions

When used preferentially, the use of neoadjuvant chemotherapy in DMPM patients was not associated with worse outcomes compared to adjuvant chemotherapy. It was well-tolerated and did not prevent surgical intervention.

Platinum resistant recurrence and early recurrence in a multi-centre cohort of patients undergoing interval cytoreductive surgery for advanced epithelial ovarian cancer

Background

Aggressive locoregional therapies like hyperthemic intraperitoneal chemotherapy(HIPEC) and total parietal peritonectomy(TPP) have been used to delay recurrence in patients with advanced ovarian cancer undergoing interval cytoreductive surgery(CRS). The aim of this retrospective study was to evaluate the incidence of platinum resistant recurrence (PRR) and early recurrence (ER)(recurrence within 6 months and 1 year of the last dose of platinum based therapy, respectively) in patients undergoing interval CRS. The secondary goal was to study impact of each of these therapies on PRR and ER.

Methods

One-hundred and fifty-three patients undergoing interval CRS from July 2018 to June 2020 were included. The surgical strategy was to perform a TPP in which the entire parietal peritoneum is resected irrespective of the disease extent or a selective parietal peritonectomy (SPP) in which only the peritoneum bearing visible residual disease is resected. The use of HIPEC was at the discretion of the treating oncologists.

Results

The median surgical PCI was 15 [range, 0-37]. A CC-0 resection was obtained in 119 (77.7%) and CC-1 in 29 (18.9%) patients. Eighty-one (53%) patients had a TPP and 72 (47%) had SPP. HIPEC was performed in 98(64%) patients. Bevacizumab maintenance was administered to 31(19.6%) patients. No patients received PARP inhibitors during first-line therapy. PRR was observed in 8(5.2%) patients and ER in 30(19.6%). The respective incidences of PRR and ER were 4.9% and 16% in the TPP group, 4.1% and 23.6% in the SPP group, 9% and 20% in the no-HIPEC group and 3% and 19.3% in the HIPEC groups. On multivariate analysis, CC-0(p=0.014) resection and HIPEC(p=0.030) were independent predictors of a low ER. All patients with PR and 70% with ER had peritoneal recurrence with or without extra-peritoneal sites of recurrence.

Conclusions

The incidence of PRR and ER in this cohort was low as compared to historical data. This low incidence could be attributed to the use of aggressive locoregional therapies like TPP and HIPEC. In future, studies should be conducted to confirm these findings and evaluate the potential additive benefit of TPP and HIPEC coupled together as well as their combination with maintenance therapies.

Extent of Disease on Visceral Peritoneal Surfaces of Mucinous Appendiceal Neoplasms Controls Survival

Objective

To determine causes of treatment failure of low-grade appendiceal mucinous neoplasms (LAMN).

Background

For 3 decades, LAMN have been treated by cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy. This combined treatment has resulted in a large change in the survival of these patients.

Methods

A retrospective review of a prospectively maintained database was performed. A restricted cohort of patients with only LAMN histology and complete CRS were included in the statistical analysis.

Results

Four hundred and fifty patients were available with a median follow-up of 15.3 years (range 10-35 years). The median age was 49.7 and there were 196 males (43.6%). The mean survival was 24.5 years. Extent of parietal peritonectomy, resection of uterus, ovaries and apex of vagina had no impact on survival. Variables that indicated an increased extent of disease on visceral peritoneal surfaces had a significant impact on survival. Early postoperative intraperitoneal chemotherapy with 5-fluorouracil did not augment hyperthermic intraperitoneal chemotherapy (HIPEC). Patients who required reoperation for recurrence or patients with class 4 adverse events had a reduced prognosis.

Conclusions

The mean survival of LAMN treated by complete CRS and perioperative chemotherapy was 24.5 years. Extent of disease quantitated on visceral peritoneal surfaces by the extent of visceral resections was the variable associated with treatment failure. Peritonectomy plus HIPEC was able to control disease on parietal peritoneal surfaces. Not only a larger extent of disease but also its location on visceral peritoneal surfaces controlled survival.

GECOP-MMC: phase IV randomized clinical trial to evaluate the efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC) with mytomicin-C after complete surgical cytoreduction in patients with colon cancer peritoneal metastases

BACKGROUND

The French PRODIGE 7 trial, published on January 2021, has raised doubts about the specific survival benefit provided by HIPEC with oxaliplatin 460 mg/m² (30 minutes) for the treatment of peritoneal metastases from colorectal cancer. However, several methodological flaws have been identified in PRODIGE 7, specially the HIPEC protocol or the choice of overall survival as the main endpoint, so its results have not been assumed as definitive, emphasizing the need for further research on HIPEC. It seems that the HIPEC protocol with high-dose mytomicin-C (35 mg/m²) is the preferred regime to evaluate in future clinical studies.

METHODS

GECOP-MMC is a prospective, open-label, randomized, multicenter phase IV clinical trial that aims to evaluate the effectiveness of HIPEC with high-dose mytomicin-C in preventing the development of peritoneal recurrence in patients with limited peritoneal metastasis from colon cancer (not rectal), after complete surgical cytoreduction. This study will be performed in 31 Spanish HIPEC centres, starting in March 2022. Additional international recruiting centres are under consideration. Two hundred sixteen patients with PCI ≤ 20, in which complete cytoreduction (CCS 0) has been obtained, will be randomized intraoperatively to arm 1 (with HIPEC) or arm 2 (without HIPEC). We will stratified randomization by surgical PCI (1-10; 11-15; 16-20). Patients in both arms will be treated with personalized systemic chemotherapy. Primary endpoint is peritoneal recurrence-free survival at 3 years. An ancillary study will evaluate the correlation between surgical and pathological PCI, comparing their respective prognostic values.

DISCUSSION

HIPEC with high-dose mytomicin-C, in patients with limited (PCI ≤ 20) and completely resected (CCS 0) peritoneal metastases, is assumed to reduce the expected risk of peritoneal recurrence from 50 to 30% at 3 years.

TRIAL REGISTRATION

EudraCT number: 2019-004679-37; Clinicaltrials.gov: NCT05250648 (registration date 02/22/2022, ).

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.

Current role for cytoreduction and HIPEC for gastric cancer with peritoneal disease

Gastric cancer (GC) is an aggressive malignancy with a high burden of peritoneal disease. Evidence regarding the use of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) to improve outcomes has been growing. However, given multiple limitations, there remains a lack of international consensus regarding the optimal treatment paradigm. This review article discusses the burden of peritoneal disease in GC patients and the role of CRS + HIPEC in all treatment intents—curative, prophylactic, and palliative.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) Combined with Surgery: A 12-Year Meta-Analysis of this Promising Treatment Strategy for Advanced Gastric Cancer at Different Stages

BACKGROUND

This meta-analysis was designed to systematically assess the effectiveness and safety of hyperthermic intraperitoneal chemotherapy (HIPEC) combined with surgery for different stages of advanced gastric cancer (AGC) during the last 12 years.

METHODS

The Cochrane Library, PubMed, Embase, Web of Science, and China National Knowledge Infrastructure (CNKI) were searched online, and papers were retrieved from other sources. Next, randomized controlled trials (RCTs) and high-quality nonrandomized controlled trials (NRCTs) were selected for this analysis. The meta-analysis was conducted with RevMan5.4 software.

RESULT

The 10 RCTs and 13 NRCTs selected for the study included 1892 patients. The overall survival rates were higher in the HIPEC group at 1 year (risk ratio [RR], 0.52; P = 0.004) and 3 years (RR, 0.63; P < 0.00001) than in the control group for the patients without peritoneal cancer, and the HIPEC group had a significant reduction in the recurrence rate (RR, 0.60; p < 0.00001). Among the patients with peritoneal carcinomatosis (PC), the HIPEC group had significantly higher overall survival rates at 1 year (RR, 0.62; P = 0.00001), 2 years (RR, 0.85; P = 0.002), and 3 years (RR, 0.87; P = 0.0001), with an increase in the overall median survival time of 4.67 months. The two groups showed no statistically significant difference in terms of complications for patients with PC (RR, 1.03; P = 0.93) or without PC (RR, 1.15; P = 0.51).

CONCLUSION

For local AGC without PC, standard surgery combined with prophylactic HIPEC could prolong survival and reduce the recurrence rate without more complications. The prognosis of this treatment strategy for patients with PC is closely related to patient selection. Complete cytoreduction combined with therapeutic HIPEC could prolong survival.

CT Enterography for Preoperative Evaluation of Peritoneal Carcinomatosis Index in Advanced Ovarian Cancer

To compare the diagnostic performance of routine CT (rCT), CT enterography (CTE) and intraoperative quantification of PCI to surgical and pathological reference standards in patients with advanced ovarian cancer, a retrospective study of 122 patients who underwent cytoreduction surgery for ovarian peritoneal carcinomatosis was conducted. Radiological, surgical, and pathological PCIs were obtained from the corresponding reports, and the latter two were considered reference standards. The radiological techniques used were rCT: 64 MDCT (32 × 1 mm) (100 mL iopromide 370 i.v., 800 mL water p.o.), and CTE: 64 MDCT (64 × 0.5 mm) (130 mL iopromide 370 i.v., 1800 mL mannitol solution p.o., 20 mg buscopan i.v.). Data were grouped by imaging technique and analyzed using total PCI and stratified by tumor burden (low-PCI < 10, high-PCI > 20). Agreement, diagnostic performance and degree of cytoreduction were evaluated. Disappointing results for rCT and CTE were obtained when using a surgical referent, but better diagnostic performance and concordance (0.86 vs. 0.78 vs. 0.62, p < 0.05) was observed when using a pathological referent—surgical PCI overestimates and overstaged patients. PCI is underestimated by rCT rather than CTE. For high-PCI, the ROC curve was mediocre for CTE and useless for rCT, as it failed to identify any cases. For low-PCI, the ROC was excellent (86% CTE vs. 75% rCT). In four cases with low-PCI as determined by rCT, cytoreduction was suboptimal. CTE has a better diagnostic performance than rCT in quantifying PCI in patients with advanced ovarian cancer, suggesting that CTE should be used as the initial technique. Surgical-PCI could be considered as an imperfect standard reference.

Limitations of laparoscopy to assess the peritoneal cancer index and eligibility for cytoreductive surgery with HIPEC in peritoneal metastasis

PURPOSE

We aimed to determine the value of laparoscopy to assess the intra-abdominal tumor extent and predict complete cytoreduction.

METHODS

All patients at our department in the period from 2017 to 2021 that underwent laparoscopy to assess peritoneal metastasis and subsequent open exploration with the intention to perform cytoreductive surgery (CRS) with HIPEC were retrospectively identified in a continuously maintained database.

RESULTS

Forty-three patients were analyzed. Peritoneal cancer index (PCI) determination by laparoscopy compared to open surgery was overestimated in five patients (11.6%), identical in eleven patients (25.6%), and underestimated in 27 patients (62.8%). PCI differences were independent of surgeons, tumor entities, and prior chemotherapy. Thirty-four patients (79.1%) were determined eligible for CRS with HIPEC during open exploration, whereas nine patients (20.9%) underwent a non-therapeutic laparotomy. Complete or almost complete cytoreduction was achieved in 33 patients (76.7%). In one patient, completeness of cytoreduction was not documented.

CONCLUSIONS

We demonstrate a moderate agreement according to weighted Cohen's kappa analysis of PCI values calculated during laparoscopy and subsequent open exploration for CRS with HIPEC. Uncertainty of PCI assessment should therefore be kept in mind when performing laparoscopy in patients with peritoneal metastasis.

Ratio of Pathological Response to Preoperative Chemotherapy in Patients Undergoing Complete Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Metastatic Colorectal Cancer Correlates with Survival

BACKGROUND

Pathological response of colorectal peritoneal metastasis (CRPM) may affect prognosis. We investigated the relationship between oncological outcomes and pathological response to chemotherapy of CRPM following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

We conducted a retrospective analysis of a prospectively maintained Peritoneal Surface Malignancies database between 2015 and 2020. Analysis included patients with CRPM who underwent a CRS/HIPEC procedure (n = 178). The cohort was divided into three groups according to the response ratio (ratio of tumor-positive specimens to the total number of specimens resected): Group A, complete response; Group B, high response ratio, and Group C, low response ratio.

RESULTS

The group demographics were similar, but the overall complication rate was higher in Group C (65.2%) compared with Groups A (55%) and B (42.8%) [p = 0.03]. Survival correlated to response ratio; the estimated median disease-free survival of Group C was 9.1 months (5.97-12.23), 14.9 months (4.72-25.08) for Group B, and was not reached in Group A (p = 0.001). The estimated median overall survival in Group C was 35 months (26.69-43.31), and was not reached in Groups A and B (p = 0.001).

CONCLUSIONS

The pathological response ratio to systemic therapy correlates with survival in patients undergoing CRS/HIPEC. This study supports the utilization of preoperative therapy for better patient selection, with a potential impact on survival.

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.

Greater-omentum lesion-score (GOLS) as a predictor of residual disease in different regions of the peritoneal cavity in patients undergoing interval cytoreductive surgery for advanced ovarian cancer and its potential clinical utility

BACKGROUND AND AIM

The greater omentum(GO) is a common site of residual disease in patients receiving neoadjuvant chemotherapy for advanced epithelial ovarian cancer. The presence of tumor in the GO could predict presence of disease in other peritoneal regions. The goal of this study was to perform a correlation between the greater-omentum lesion-score(GOLS) and presence of disease in different peritoneal regions and determine its potential utility in guiding interval cytoreductive surgery(CRS).

METHODS

This prospective study included 134 patients undergoing interval CRS from July 1, 2018 to June 30, 2020. Each region of Sugarbaker's Peritobneal Cancer Index(PCI) was given a lesion score(LS) from 0 to 3 according to the diameter of the largest tumor in the region. The GOLS was recorded separately from other structures in the region. Correlation between the GOLS and surgical and pathological LS in each region was performed.

RESULTS

As the GOLS increased, the incidence of disease(surgical LS) in other regions of the peritoneal cavity increased. Receiver operating characteristic(ROC) curves showed area under curve more than 80% for regions 1-2 and 7-8 indicating a high probability of disease in these regions in patients with GOLS 1-3. The positive predictive value(PPV) of preoperative imaging for GOLS was 95.7%. No cut-off of the GOLS could predict presence of disease on pathology with more than 70% accuracy.

CONCLUSIONS

Presence of disease in the GO warrants performing upper abdominal exploration and/or cytoreduction and interval CRS should be planned accordingly in these patients. Imaging has a high PPV in detecting disease in the GO.

Implications of Pathologic Findings in Cytoreductive Surgery Specimens on Treatment of Colorectal Peritoneal Metastases: Results of a Prospective Multicentric Study

BACKGROUND

A surgical peritoneal cancer index of >20 is often used to exclude patients from cytoreductive surgery for colorectal peritoneal metastases. The pathologic peritoneal cancer index in these patients may be <20.

OBJECTIVE

The purpose of this study was to compare the pathologic and surgical findings and to look at potential pathologic prognostic factors.

DESIGN

This is a prospective observational study including patients undergoing cytoreductive surgery.

SETTINGS

The study was carried out at 3 peritoneal surface malignancy centers, 1 in France and 2 in India.

PATIENTS

One-hundred patients were included from July 1, 2018, to June 30, 2019.

MAIN OUTCOME MEASURES

The pathologic peritoneal cancer index, peritoneal disease distribution, pathologic response to chemotherapy, factors affecting them and their relation with surgical findings, and potential prognostic value were explored.

RESULTS

Ninety percent had colonic primaries. Fifty-one percent had left-sided tumors. The median surgical peritoneal cancer index was 4 (range, 0-35). Upper regions were involved in 32% and small bowel regions in 26%, and their involvement increased with a higher peritoneal cancer index (p < 0.001). The median pathologic peritoneal cancer index was 2 (range, 0-27) and was less than the surgical peritoneal cancer index in 57%. A pathologic complete response was obtained in 25%. Patients with pathologic complete response received more antiepidermal growth factor receptor therapy (p = 0.008); more leucovorin, 5-fluorouracil, and oxaliplatin; and folinic acid, fluorouracilirin, irinotecan hydrochloride, and oxaliplatin (p < 0.001). In 7 patients with a surgical peritoneal cancer index of >20, pathologic peritoneal cancer index was <20 in 4 patients. Disease in the primary tumor/anastomotic site was found in ≈80%.

LIMITATIONS

Survival outcomes are not available.

CONCLUSIONS

Surgical peritoneal cancer index of >20 should not be the sole factor to exclude patients from surgery, especially in responders to systemic therapies. The pathologic peritoneal cancer index, pathologic response to systemic chemotherapy, and disease distribution in the peritoneal cavity should be meticulously documented. Correlation with survival will define their future prognostic value. The primary anastomotic site is a common site for peritoneal disease and should be carefully evaluated in all patients. See Video Abstract at http://links.lww.com/DCR/B490. IMPLICACIONES DE LOS HALLAZGOS PATOLÓGICOS EN MUESTRAS DE CIRUGÍA CITORREDUCTORA EN EL TRATAMIENTO DE METÁSTASIS PERITONEALES COLORRECTALES: RESULTADOS DE UN ESTUDIO PROSPECTIVO MULTICÉNTRICO: Una ICP quirúrgica de >20 se utiliza a menudo para excluir a los pacientes de la cirugía citorreductora por metástasis peritoneales colorrectales. La PCI patológica en estos pacientes puede ser <20.Comparar los hallazgos patológicos y quirúrgicos y observar los posibles factores pronósticos patológicos.Se trata de un estudio observacional prospectivo que incluye a pacientes sometidos a cirugía citorreductora.El estudio se llevó a cabo en tres centros de malignidad de la superficie peritoneal, 1 en Francia y 2 en India.Se incluyeron 100 pacientes desde el 1 de julio de 2018 al 30 de junio de 2019.No hubo intervención terapéutica.Se exploró la ICP patológica, la distribución de la enfermedad peritoneal, la respuesta patológica a la quimioterapia, los factores que la afectan y su relación con los hallazgos quirúrgicos y el valor pronóstico potencial.El noventa por ciento tenía lesiones primarias colónicas. El 51% tenía tumores del lado izquierdo. La mediana de la ICP quirúrgica 4 [0-35]. Las regiones superiores estuvieron involucradas en el 32% y las regiones del intestino delgado en un 26% y su participación aumentó con una ICP más alta (p <0,001). La mediana de la ICP patológica fue 2 [0-27] y fue menor que la ICP quirúrgica en el 57%. Se obtuvo respuesta patológica completa en el 25%. Los pacientes con respuesta patológica completa recibieron más terapia anti-EGFR (p = 0,008) y más FOLFOX y FOLFIRINOX (p <0,001). En 7 pacientes con una ICP quirúrgica de> 20, la ICP patológica fue menor de 20 en 4 pacientes. Se encontró enfermedad en el tumor primario/anastomósis en casi el 80%.Los resultados de supervivencia no están disponibles.La ICP quirúrgica de> 20 no debería ser el único factor para excluir a los pacientes de la cirugía, especialmente en los que responden a las terapias sistémicas. La PCI patológica, la respuesta patológica a la quimioterapia sistémica y la distribución de la enfermedad en la cavidad peritoneal deben documentarse meticulosamente. La correlación con la supervivencia definirá su valor pronóstico futuro. El sitio anastomótico primario es un sitio común de enfermedad peritoneal y debe evaluarse cuidadosamente en todos los pacientes. Consulte Video Resumen en http://links.lww.com/DCR/Bxxx. (Traducción-Dr. Gonzalo Hagerman).

Total parietal peritonectomy performed during interval cytoreductive surgery for advanced epithelial serous ovarian cancer results in a low incidence of platinum resistant recurrence- results of a prospective multi-centre study

BACKGROUND

The reported incidence of platinum resistant recurrence (PRR) (recurrence within 6 months of the last dose of platinum therapy) after interval debulking/cytoreductive surgery (CRS) is high compared to that after primary CRS. The goal was to study PRR following a total parietal peritonectomy (TPP), that addresses occult disease more completely.

METHODS

This is a prospective multi-center study (CTRI/2018/08/015350). A TPP was performed during interval CRS following a fixed surgical protocol. Patients with a follow-up of 6 months(M) or more were included in this analysis. The incidence and patterns of PRR and factors affecting recurrence were analyzed.

RESULTS

From July 2018 to October 2019, 70 patients with serous carcinoma were included. The median surgical PCI was 15 [range 5-37]. A CC-0 resection was obtained in 55 (78.5%); CC-1 in 10 (14.2%). Occult residual disease was seen in 40%. At a median follow-up of 13 months, 17 (24.2%) had developed recurrence/progression. PRR was seen in 5 (7.1%) patients. The sites of progression (>1 in 2 patients) were pleura (n = 1), visceral peritoneum (n = 2), retroperitoneal nodes (n = 2), mediastinal nodes (n = 1) and small bowel mesentery (n = 2). Overall, though the most common site of recurrence was the visceral peritoneum (N = 9), seven (>40%) patients did not develop recurrence in the visceral peritoneum. Patients with high PCI and grade 3-4 complications had a higher probability of developing recurrence.

CONCLUSIONS

TPP performed during interval CRS resulted in a very low incidence of PRR. These findings need confirmation in a larger series. The benefit of TPP over conventional surgery should be evaluated in a randomized trial.

Treatment options for advanced gastric cancer with peritoneal metastasis: experience from a single institution in Korea

Purpose

This study aimed to compare treatment options and outcomes based on peritoneal cancer index (PCI) among patients with peritoneal metastasis (PM) of advanced gastric cancer (AGC).

Methods

Between January 2016 and July 2019, clinicopathological data of patients with AGC diagnosed with PM were reviewed. Different treatment methods were performed according to the PCI score: (1) group A (PCI ≤ 13) received cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) with postoperative intraperitoneal (IP) and systemic chemotherapy (n = 29), while (2) group B (PCI > 13) received IP chemotherapy with systemic chemotherapy (n = 22).

Results

Clinical outcomes of 51 patients at the Dankook University Hospital were reviewed. Group A had a significantly lower mean PCI score (9.8 ± 6.9 vs. 32.6 ± 7.1, P < 0.01) than group B, with 25 patients (86.2%) achieving complete cytoreduction. Complications occurred in 16 patients (31.4%), none of who suffered mortality (group A: 11 patients, 37.9% vs. group B: 5 patients, 22.7%; P = 0.25). Among the morbidity, 5 cases (17.2%) and 2 cases (9.1%) exhibited a Clavien-Dindo grade greater than III in groups A and B, respectively (P = 0.04). Groups A and B had an overall median survival time of 34.0 and 16.0 months, respectively (P = 0.03).

Conclusion

Patients with PM of AGC received different treatments according to their PCI score. When accompanied with careful patient selection, our approach may be considered an acceptable option for the treatment of PM of AGC.

Prospective correlation of the radiological, surgical and pathological findings in patients undergoing cytoreductive surgery for colorectal peritoneal metastases: implications for the preoperative estimation of the peritoneal cancer index

AIM

The peritoneal cancer index (PCI) is one of the strongest prognostic factors in patients undergoing cytoreductive surgery (CRS) for colorectal peritoneal metastases. Using pathological evaluation, however, the disease extent differs in a large proportion of patients. Our aim was to study the correlation between the radiological (rPCI), surgical (sPCI) and pathological (pPCI) PCI in order to determine factors affecting the discordance between these indices and their potential therapeutic implications.

METHOD

From July 2018 to December 2019, 128 patients were included in this study. The radiological, pathological and surgical findings were compared. A protocol for pathological evaluation was followed at all centres.

RESULTS

All patients underwent a CT scan and 102 (79.6%) had a peritoneal MRI. The rPCI was the same as the sPCI in 81 (63.2%) patients and the pPCI in 93 (72.6%). Concordance was significantly lower for moderate-volume (sPCI 13-20) and high-volume (sPCI > 20) disease than for low-volume disease (sPCI 0-12) (P < 0.001 for sPCI; P = 0.001 for pPCI). The accuracy of imaging in predicting presence/absence of disease upon pathological evaluation ranged from 63% to 97% in the different regions of the PCI. The pPCI concurred with the sPCI in 86 (68.8%) patients. Of the nine patients with sPCI > 20, the pPCI was less than 20 in six.

CONCLUSION

The rPCI and sPCI both concurred with pPCI in approximately two thirds of patients. Preoperative evaluation should focus on the range in which the sPCI lies and not its absolute value. Radiological evaluation did not overestimate sPCI in any patient with high/moderate-volume disease. The benefit of CRS in patients with a high r/sPCI (> 20) who respond to systemic therapies should be prospectively evaluated.

Clinical and Radiologic Predictors of a Pathologic Complete Response to Neoadjuvant Chemotherapy (NACT) in Patients Undergoing Cytoreductive Surgery for Colorectal Peritoneal Metastases: Results of a Prospective Multi-center Study

BACKGROUND

Patients undergoing cytoreductive surgery for colorectal peritoneal metastases who have a pathologic complete response (pCR) to neoadjuvant chemotherapy experience a significantly longer survival than those with residual disease. This response is known only after surgery. This study aimed to examine clinical and radiologic predictors of a pCR.

METHODS

From July 2018 to December 2019, the study prospectively enrolled 120 patients. The clinical and radiologic findings were compared between patients with and without a pCR. A protocol for pathologic evaluation was followed.

RESULTS

A pCR was observed in 34 patients (28.3%). Receiver operating characteristic (ROC) curves showed that patients with a surgical Peritoneal Cancer Index (sPCI) of 3 or lower had an 80% probability of experiencing a pCR, and that patients with a radiologic PCI (rPCI) of 2 or lower had a 70% probability of experiencing a pCR. A pCR was correctly predicted for 47% of the patients by imaging and for 44.4% of the patients by surgical evaluation. The site of primary tumor, the timing of peritoneal metastasis (PM), histology, tumor marker positivity, and mutations in known poor prognostic genes (KRAS) did not differ between the patients with and those without pCR. The primary tumor showed residual disease in 23.5% and regional nodes in 26.4% of the patients with pCR.

CONCLUSIONS

The rPCI and sPCI concurred with a pCR in less than 50% of the patients. The patients with a lower PCI had greater concordance. An sPCI of 3 or lower was predictive of a pCR in 80% of the patients. The impact of KRAS mutations on pCR should be evaluated in a larger series. The predictors of pCR and response to systemic chemotherapy should be incorporated in prognostic scores used to select patients for surgery.

Distribution of residual disease in the peritoneum following neoadjuvant chemotherapy in advanced epithelial ovarian cancer and its potential therapeutic implications

INTRODUCTION

Residual disease in 'normal appearing' peritoneum is seen in nearly 30% of the patients following neoadjuvant chemotherapy (NACT) for advanced ovarian cancer. The goal was to study the sequence of response in different regions, the commonest sites of occult residual disease, its incidence in different peritoneal regions and the potential therapeutic implications of these.

METHODS

This was a prospective multi-centre study (July 2018-June 2019). Pathological evaluation of cytoreductive surgery specimens was performed according to a fixed protocol. Prevalence of residual disease in different regions was used to study patterns of response and distribution of residual disease.

RESULT

In 85 patients treated between July 2018 to June 2019, microscopic disease in 'normal appearing' peritoneal regions was seen in 22 (25.2%) and in normal peritoneum around tumor nodules in 30 (35.2%) patients. Regions 4 and 8 of Sugarbaker's PCI had the highest incidence of occult disease and regions 9 and 10 the lowest. The response to chemotherapy occurred in a similar manner in over 95%- the least common site of residual disease was the small bowel mesentery, followed by upper regions (regions 1-3), omentum and middle regions (regions 0, 4, 8), lower regions (regions 5-7) and lastly the ovaries.

CONCLUSIONS

During interval CRS, based on the disease mapping provided in this manuscript, regions that have a high probability of residual disease should be explored and dissected. Complete resection of involved the peritoneal region can completely address the occult disease. The role of resection of the entire region as well as 'normal appearing' parietal peritoneal regions should be prospectively evaluated.

Total Parietal Peritonectomy Can Be Performed with Acceptable Morbidity for Patients with Advanced Ovarian Cancer After Neoadjuvant Chemotherapy: Results From a Prospective Multi-centric Study

BACKGROUND

Total parietal peritonectomy (TPP) removes areas of "normal-appearing" parietal peritoneum bearing microscopic residual disease and has the potential to improve survival of patients undergoing interval cytoreductive surgery (CRS) for advanced serous epithelial ovarian cancer. This report presents the morbidity outcomes for the first 50 patients enrolled in TORPEDO (CTRI/2018/12/016789), a prospective study.

METHODS

All the patients underwent a TPP during interval CRS. A surgical protocol that includes a description of the boundaries for each of the five peritonectomies was followed. The common toxicology criteria for adverse events (CTCAE) classification was used to record 90-day morbidity and mortality.

RESULTS

The median Peritoneal Cancer Index (PCI) for 50 patients was 15 (range, 5-37). A complete cytoreduction (CC-0 resection) was obtained in 80%, a CC-1 resection in 16%. A bowel resection was performed in 70% of the patients. Grade 3 or 4 complications were seen in 11 patients (22%), and one patient died within 90 days after surgery due to intraperitoneal hemorrhage. The most common complications were postoperative fluid collection requiring aspiration (n = 5), intraperitoneal hemorrhage (n = 2), abdominal wound dehiscence (n = 2), pseudo-obstruction (n = 1), urinary sepsis (n = 2), and ileostomy-related complications (n = 2). No bowel fistulas or anastomotic leaks occurred. Microscopic disease in 'normal appearing' peritoneum adjacent to tumor nodules was observed in 46% of the patients, and in regions given a lesion score of 0 in 34%. The parietal peritoneal regions (0-8) had a higher incidence of residual disease (p < 0.001) and occult disease (p < 0.001).

CONCLUSIONS

During interval CRS, TPP can be performed with acceptable morbidity and mortality. The pathologic findings further support this therapeutic rationale. Survival outcomes should determine the future role of such a procedure in routine clinical practice.

Extent and distribution of peritoneal disease in patients undergoing cytoreductive surgery for first platinum sensitive recurrence in ovarian cancer and its potential therapeutic implications

BACKGROUND

Selected patients with platinum sensitive recurrent ovarian cancer may benefit from cytoreductive surgery (CRS). The aim was to study the pattern of peritoneal involvement in these patients that has not been done before.

METHODS

A comparison was made between the surgical and pathological findings in 60 patients undergoing salvage CRS from July 2018 to December 2019. The sites of residual disease, correlation with surgical and pathological peritoneal cancer index (PCI), small bowel involvement and regional lymph node involvement were studied.

RESULTS

Fifty-eight (96.6%) had serous carcinoma and 2 (3.4%) clear cell carcinoma. The median surgical PCI (sPCI) was 7 [range 0-27] and median pathological PCI (pPCI) 4 [range 0-21]. CC-0 resection was performed in 81.6%. The upper regions (region 1,2,3) were the commonest sites of residual disease (63.3%) followed by lower regions (region 5,6,7) in 55.0%, middle regions (regions 0,4,8) in 53.3% and small bowel regions (regions 9-12) in 26.6%. Small bowel involvement was associated with a higher sPCI and pPCI (p < 0.001 for both). Regional nodes were involved in 46.6%. A pathological complete response was seen in 8 (13.3%) patients of which 2 had residual disease in regional nodes. Microscopic disease in 'normal appearing' peritoneum was seen in 21%.

CONCLUSIONS

The parietal peritoneum was the commonest site of recurrence. Small bowel involvement occurred late and was associated with more extensive disease. Regional lymph node involvement was seen nearly 50% and was a common site for occult disease. The role of more extensive parietal peritoneal resection for recurrent disease should be evaluated prospectively.