Pathological assessment of cytoreductive surgery specimens and its unexplored prognostic potential-a prospective multi-centric study

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.

Perioperative outcomes and platinum resistant recurrence in patients undergoing systematic, protocol-based, total parietal peritonectomy during interval cytoreductive surgery for advanced ovarian cancer: results of the TORPEDO study

OBJECTIVE

The TORPEDO (CTRI/2018/12/016789) is the single-arm, prospective, interventional study evaluating the role of a total parietal peritonectomy (TPP) in patients undergoing interval cytoreductive surgery (iCRS). In this manuscript, we report the perioperative outcomes and platinum resistant recurrence (PRR) in 218 patients enrolled in the study.

METHODS

A TPP was performed in all patients undergoing iCRS irrespective of the residual disease extent. hyperthermic intraperitoneal chemotherapy (HIPEC) was performed as per the clinician's discretion with 75 mg/m² of cisplatin. Maintenance therapy was also used at the discretion of the treating clinicians.

RESULTS

From 9th December 2018 to 31st July 2022 (recruitment complete), 218 patients were enrolled at 4 medical centers in India. The median surgical peritoneal cancer index was 14 and a complete gross resection was achieved in 95.8%. HIPEC was performed in 130 (59.6%) patients. The 90-day major morbidity was 17.4% and 2.7% patients died within 90 days of surgery. Adjuvant chemotherapy was delayed beyond 6 weeks in 7.3%. At a median follow-up of 19 months (95% confidence interval [CI]=15.9-35 months), 101 (46.3%) recurrences and 19 (8.7%) deaths had occurred. The median progression-free survival was 22 months (95% CI=17-35 months) and the median overall survival (OS) not reached. Platinum resistant recurrence was observed in 6.4%. The projected 3-year OS was 81.5% and in 80 patients treated before may 2020, it was 77.5%.

CONCLUSION

The morbidity and mortality of TPP with or without HIPEC performed during iCRS is acceptable. The incidence was of PRR is low. Early survival results are encouraging and warrant conduction of a randomized controlled trial comparing TPP with conventional surgery.

Survival Dynamics in Advanced Ovarian Cancer: R2 Resection Versus No-Surgery Paths Explored

BACKGROUND

Cytoreductive surgery is critical for optimal tumor clearance in advanced epithelial ovarian cancer (EOC). Despite best efforts, some patients may experience R2 (>1 cm) resection, while others may not undergo surgery at all. We aimed to compare outcomes between advanced EOC patients undergoing R2 resection and those who had no surgery.

METHODS

Retrospective data from 51 patients with R2 resection were compared to 122 patients with no surgery between January 2015 and December 2019 at a UK tertiary referral centre. Progression-free survival (PFS) and overall survival (OS) were the study endpoints. Principal Component Analysis and Term Frequency - Inverse Document Frequency scores were utilized for data discrimination and prediction of R>2 cm from computed tomography pre-operative reports, respectively.

RESULTS

No statistical significance was observed, except for age (73 vs 67 years in the no- surgery vs R2 group, P: .001). Principal Components explained 34% of data variances. Reasons for no surgery included age, co-morbidities, patient preference, refractory disease, patient deterioration or disease progression, and absence of measurable intra- abdominal disease). The median PFS and OS were 12 and 14 months for no-surgery, vs 14 and 26 months for R2 (P: .138 and P: .001, respectively). Serous histology and performance status independently predicted PFS in both no-surgery and R2 cohorts. In the no-surgery cohort, serous histology independently predicted OS, while in the R2 cohorts, both serous histology and adjuvant chemotherapy were independent prognostic features for OS. The bi-grams "abdominopelvic ascites" and "solid omental" were amongst those best discriminating between R>2 cm and R1-2 cm.

CONCLUSIONS

R2 resection and no-surgery cohorts displayed unfavourable prognosis with a notable degree of uniformity. When cytoreduction results in suboptimal results, the survival benefit may still be higher compared to those who underwent no surgery.

Upper-Abdominal Cytoreduction for Advanced Ovarian Cancer—Therapeutic Rationale, Surgical Anatomy and Techniques of Cytoreduction

Cytoreductive surgery (CRS) is the cornerstone of treating advanced ovarian cancer. Approximately 60–70% of patients with advanced ovarian cancer will have involvement in the upper abdomen or the supracolic compartment of the abdominal cavity. Though the involvement of this region results in poorer survival compared, complete cytoreduction benefits overall survival, making upper-abdominal cytoreduction an essential component of CRS for advanced ovarian cancer. The upper abdomen constitutes several vital organs and large blood vessels draped with the parietal or visceral peritoneum, common sites of disease in ovarian cancer. A surgeon treating advanced ovarian cancer should be well versed in upper-abdominal cytoreduction techniques, including diaphragmatic peritonectomy and diaphragm resection, lesser omentectomy, splenectomy with or without distal pancreatectomy, liver resection, cholecystectomy, and suprarenal retroperitoneal lymphadenectomy. Other procedures such as clearance of the periportal region, Glisson’s capsulectomy, clearance of the superior recess of the lesser sac, and Morrison’s pouch are essential as these regions are often involved in ovarian cancer. This manuscript covers the surgical anatomy of the upper abdomen, the techniques and therapeutic rationale of upper-abdominal cytoreduction, and specific measures for perioperative management of these patients. The main focus is the description of various peritonectomies and regional lymphadenectomies.

Lymph node positive pseudomyxoma peritonei

BACKGROUND

Appendiceal mucinous neoplasms are routinely accompanied by peritoneal metastases at the time of diagnosis of the primary appendiceal tumor. In contrast, liver metastases and lymph node metastases are unusual.

METHODS

From an extensive database, patients with lymph node metastases identified at the time of primary appendiceal cancer resection were selected for special study. The clinical, treatment-related and histologic variables of this group of patients were statistically analyzed for their impact on overall survival.

RESULTS

From a prospectively maintained database of 685 patients with a complete cytoreduction of a mucinous appendiceal neoplasm with peritoneal dissemination, 39 patients (5.6%) had lymph node metastases at the time of primary diagnosis. The median follow-up was 5.0 years and overall median survival was 6.0 years. Histologically, 6 of these patients (15.4%) had an appendiceal mucinous neoplasm - Intermediate type (MACA-Int). In 5 patients, the involved lymph nodes were not within the ileocolic lymph node group. The 7 patients (17.9%) who had a complete or near complete response to neoadjuvant chemotherapy prior to definite cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) showed prolonged survival (HR 4.8 (1.1, 20.5) p = 0.0323). A prior right colon resection required repeat resection in 87% of patients.

CONCLUSION

Long-term survival is unusual but occasionally seen in this group of patients. Response to neoadjuvant chemotherapy is an important determinant of a favorable outcome.

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.

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.

Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Carcinomatosis from Epithelial Ovarian Cancer: A 20-Year Single-Center Experience

Despite improvement in treatments, the peritoneum remains the primary site of relapse in most ovarian cancer cases. Patients who underwent cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for peritoneal carcinomatosis from epithelial ovarian cancer were reviewed. Kaplan-Meier curves and multivariate Cox analyses were used to identify survival rates and prognostic factors. This study included 158 patients. The procedure was mostly performed for recurrent disease (46.8%) and high-grade serous carcinoma (58.2%). The median peritoneal cancer index was 14, and complete cytoreduction was obtained in 87.9% of cases. Grade IV morbidity occurred in 15.2% of patients, mostly requiring surgical reoperation, and one patient (0.6%) died within 90 days. The median follow-up was 63.5 months. The Kaplan-Meier 5-year overall survival (OS) and disease-free survival (DFS) rates were 42.1% and 24.3%, respectively. Multiple regression logistic analyses demonstrated that the completeness of cytoreduction (CC) score (p ≤ 0.0001), pancreatic resection (p ≤ 0.0001) and number of resections (p = 0.001) were significant factors influencing OS; whereas the CC score (p ≤ 0.0001) and diaphragmatic procedures (p = 0.01) were significant for DFS. The addition of hyperthermic intraperitoneal chemotherapy to standard multimodality therapy may improve outcomes in both primary and recurrent epithelial ovarian cancer without impairing early postoperative results, but the exact timing has not yet been established. Prospective randomized studies will clarify the role and indications of this approach.

Pattern of recurrence after interval cytoreductive surgery and HIPEC following neoadjuvant chemotherapy in primary advanced stage IIIC/IVA epithelial ovarian cancer

OBJECTIVE

The aim of this study was to evaluate the patterns of recurrence and factors affecting the same after interval cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in primary stage IIIC and IV A epithelial ovarian cancer.

METHODS

In this retrospective multicentric study, all patients with FIGO stages III-C and IV-A epithelial ovarian carcinoma were treated with CRS and HIPEC after receiving neoadjuvant chemotherapy. Relevant clinical and demographic data were captured. Multivariable logistic regression was performed to evaluate the factors affecting recurrence after CRS and HIPEC.

RESULTS

From January 2017 to Jan 2020, 97, consecutive patients of Stage IIIC/IVA epithelial ovarian cancer underwent interval cytoreductive surgery and HIPEC after receiving neoadjuvant chemotherapy. The median duration of follow up duration was 20 months [1-36months]. 21/97 (21.6%) patients presented with disease recurrence. Visceral recurrences involving the lungs, liver and brain were seen in 8/21 (38%) of cases and comprised the commonest sites. On multivariable analysis, nodal involvement (p = 0.05), selective peritonectomy (p = 0.001) and leaving behind residual disease <0.25 mm (CC1) (p = 0.01) was associated with increased risk of disease recurrence. Extent of peritonectomy (OS,p = 0.56, PFS p = 0.047, Log Rank test) and nodal positivity (OS, p = 0.13,PFS,p = 0.057, Log Rank test) were found to impact progression free survival but had no impact on overall survival.

CONCLUSION

There is a higher incidence of systemic recurrences in patients with Stage IIIC/IVA epithelial ovarian carcinoma after CRS and HIPEC. Extent of peritonectomy and nodal clearance impacts patterns of recurrence and progression free survival.

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.

Advances with pharmacotherapy for peritoneal metastasis

INTRODUCTION

A new treatment strategy involving cytoreductive surgery (CRS) combined with perioperative intraperitoneal (IP) chemotherapy was proposed in 1999 by the Peritoneal Surface Oncology Group International, and the strategy is now justified as a state-of-the-art treatment to improve the long-term survival of patients with peritoneal metastasis (PM). To achieve cure in the patients with PM, complete removal of macroscopic tumors and eradication of micrometastasis on the peritoneum, left after CRS are essential. Systemic chemotherapy is not indicated for the treatment of PM. In contrast, intraperitoneal (IP) chemotherapy brings about significantly higher locoregional dose intensity in the peritoneal cavity and subperitoneal tissues. In combination with anticancer drugs, hyperthermia enhances cytotoxicity against cancer cells.

AREA COVERED

This article provides a systematic overview of PM from various cancers including gastric, colorectal, small bowel, appendiceal cancer, and mesothelioma. It also includes all the essential aspects of therapy.

EXPERT OPINION

CRS plus perioperative intraperitoneal chemotherapy is safe with acceptable morbidity and mortality. It is justified as a standard treatment to improve the long-term survival of patients with PM and is now performed with curative intent for PM from various malignancies.

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.

Extent of Peritoneal Resection for Peritoneal Metastases: Looking Beyond a Complete Cytoreduction

Completeness of cytoreduction is one of the most important prognostic factors impacting outcomes of cytoreductive surgery (CRS). To what extent the surrounding normal peritoneum needs to be removed is not known. We hypothesized that the extent of peritoneal resection should be different for different tumors and performed this study to find evidence to support this rationale. To determine the extent of resection of surrounding tissue for any tumor, the mechanisms of tumor development and spread, tumor morphology, the possibility of finding disease in the surrounding normal tissue, and the pattern of lymph node metastases should be known. Surgical resections also depend on patterns of recurrence and the impact of varying extent of resection on survival. We performed a review of literature pertaining to pathways and patterns of peritoneal cancer spread to determine the scientific basis for the extent of peritonectomy. We also reviewed studies comparing less and more extensive peritoneal resection. There is no consensus on the extent of lymphadenectomy required for most PM. Based on this review, we provide recommendations for the extent of peritoneal resection and the extent of lymph node dissection that should be performed for some common peritoneal tumors and identify areas that require further research. We propose that a systematic method of synoptic reporting of pathological specimens of CRS should be developed to capture information regarding the disease distribution within the peritoneal cavity and morphology of PM from different tumors. This can in future be used to establish standard guidelines for such resections.

Target region resection in patients undergoing cytoreductive surgery for peritoneal metastases-is it necessary in absence of visible disease?

BACKGROUND

The aim was to study the patterns of target region (greater omentum, lesser omentum, falciform and umbilical round ligament) involvement in patients undergoing cytoreductive surgery (CRS) from various primary tumors, factors affecting involvement and implications on surgical practice.

METHODS

All patients undergoing CRS from July 2018 to December 2018 were included in this prospective study. The incidence of target region involvement in presence and absence of visible disease and the impact of primary tumor site, PCI and other variables on target region involvement was evaluated.

RESULTS

In 191 patients, greater omentum was involved in over 15% of patients irrespective of the primary tumor type and in 15.7% in absence of visible disease. 75% of these had PCI <20. The involvement of the other three target regions was higher than 20% in ovarian cancer, appendiceal tumors and peritoneal mesothelioma. Involvement of these 3 regions was associated with a higher PCI (p < 0.001 for all) and omental involvement (p < 0.001for all). 2.1% of colorectal cancer patients had umbilical round ligament involvement, 4.2% had falciform ligament involvement and none had lesser omentum involvement.

CONCLUSIONS

Target region involvement varies according to primary tumour site and disease extent. Resection of the greater omentum should be performed during CRS for PM arising from all primary sites. Resection of other target organs may be performed for selected patients with ovarian cancer, peritoneal mesothelioma and mucinous appendiceal tumors in absence of visible disease. For other patients, it should be done only in presence of visible disease.