Prognostic impact of positive microscopic margins (R1 resection) in patients with GIST (gastrointestinal stromal tumours): Results of a multicenter European study.

BACKGROUND: Although several prognostic factors in GIST have been well studied such as tumour size, mitotic rate, or localization, the influence of microscopic margins or R1 resection remains controversial. The aim of this study was to evaluate the influence of R1 resection on the prognosis of GIST in a large multicentre retrospective series of patients. METHODS: From 2001 to 2013, 1413 patients who underwent surgery for any site of GIST were identified from 61 European centers. 1098 patients were included, excluding synchronous metastases, concurrent malignancies, R2 resection or GIST recurrence. Tumour rupture (TR) was reclassified according to the Oslo sarcoma classification. Cox proportional hazards ratio and Kaplan-Meier survival estimates were used to analyse 5-year recurrence-free survival (RFS). RESULTS: Of 1098 patients, 38 (3%) underwent R1 resection with a risk of TR of 11%. The 5-year RFS was 89.6% with a median follow-up of 81 months [range: 31.2-152 months]. On univariate analysis, lower RFS was significantly associated with R1 resection [HR = 2.13; p = 0.04], high risk score according to the modified NIH classification, administration of adjuvant therapy [HR = 2.24; p < 0.001] and intraoperative complications [HR = 2.82; p < 0.001]. Only intraoperative complications [HR = 1.79; p = 0.02] and high risk according to the modified NIH classification including the updated definition of TR [HR = 3.43; p = 0.04] remained significant on multivariate analysis. CONCLUSION: This study shows that positive microscopic margins are not an independent predictive factor for RFS in GIST when taking into account the up-dated classification of TR. R1 resection may be considered a reasonable alternative to avoid major functional sequelae and should not lead to reoperation.

Circadian rhythm and circulating cell-free DNA release on healthy subjects.

In the last decade, clinical studies have investigated the clinical relevance of circulating cell-free-DNA (ccfDNA) as a diagnostic and prognosis tool in various diseases including cancers. However, limited knowledge on ccfDNA biology restrains its full development in the clinical practice. To improve our understanding, we evaluated the impact of the circadian rhythm on ccfDNA release in healthy subjects over a 24-h period. 10 healthy female subjects underwent blood sampling at 8am and 20 healthy male subjects underwent serial blood sampling (8:00 AM, 9:00 AM, 12:00 PM, 4:00 PM, 8:00 PM, 12:00 AM, 4 AM (+ 1 Day) and 8 AM (+ 1 Day)). We performed digital droplet-based PCR (ddPCR) assays to target 2 DNA fragments (69 & 243 bp) located in the KRAS gene to determine the ccfDNA concentration and fragmentation profile. As control, half of the samples were re-analyzed by capillary miniaturized electrophoresis (BIAbooster system). Overall, we did not detect any influence of the circadian rhythm on ccfDNA release. Instead, we observed a decrease in the ccfDNA concentration after meal ingestion, suggesting either a post-prandial effect or a technical detection bias due to a higher plasma load in lipids and triglycerides. We also noticed a potential effect of gender, weight and creatinine levels on ccfDNA concentration.

Iatrogenic ureteral injury during colorectal surgery has a significant impact on patient outcomes: a French multicentric retrospective cohort study.

AIM: The long-term urological sequelae after iatrogenic ureteral injury (IUI) during colorectal surgery are not clearly known. The aims of this work were to report the incidence of IUI and to analyse the long-term consequences of urological late complications and their impact on oncological results of IUI occurring during colorectal surgery through a French multicentric experience (GRECCAR group). METHOD: All the patients who presented with IUI during colorectal surgery between 2010 and 2019 were retrospectively included. Patients with ureteral involvement needing en bloc resection, delayed ureteral stricture or noncolorectal surgery were not considered. RESULTS: A total of 202 patients (93 men, mean age 63 ± 14 years) were identified in 29 centres, corresponding to 0.32% of colorectal surgeries (n = 63 562). Index colorectal surgery was mainly oncological (n = 130, 64%). IUI was diagnosed postoperatively in 112 patients (55%) after a mean delay of 11 ± 9 days. Intraoperative diagnosis of IUI was significantly associated with shorter length of stay (21 ± 22 days vs. 34 ± 22 days, p < 0.0001), lower rates of postoperative hydronephrosis (2% vs. 10%, p = 0.04), anastomotic complication (7% vs. 22.5%, p = 0.002) and thromboembolic event (0% vs. 6%, p = 0.02) than postoperative diagnosis of IUI. Delayed chemotherapy because of IUI was reported in 27% of patients. At the end of the follow-up [3 ± 2.6 years (1 month-13 years)], 72 patients presented with urological sequalae (36%). Six patients (3%) required a nephrectomy. CONCLUSION: IUI during colorectal surgery has few consequences for the patients if recognized early. Long-term urological sequelae can occur in a third of patients. IUI may affect oncological outcomes in colorectal surgery by delaying adjuvant chemotherapy, especially when the ureteral injury is not diagnosed peroperatively.

Robotic-assisted surgery for mid and low rectal cancer: a long but safe learning curve.

The number of robotic-assisted procedures for rectal cancer is rising. The risk of this procedure when performed by surgeon with limited robotic experience is unknown and the precise duration of the learning curve debated. We, therefore, aimed to analyze the learning curve and its related safety in a single center before the development of mentoring programs. We prospectively recorded all robotic procedures performed for colorectal cancer between 2015 and 2020 by a single surgeon. Operative times for partial and total proctectomy were analyzed. The learning curve was defined by comparison with the standard duration of the laparoscopic procedure performed in expert centers (published in GRECCAR 5 and GRECCAR 6 trials) and calculated using a cumulative summation for learning curve test (LC-CUSUM). Among the 174 patients operated for colorectal cancer, we analyzed the outcomes of the 89 patients operated by partial and total robotic proctectomy. To reach repeatedly the same surgical duration as laparoscopic procedure for partial or complete proctectomy, the LC-CUSUM identified a learning curve of 57 patients. A severe morbidity in this population, defined by Clavien-Dindo classification ≥ 3, was observed in 15 cases (16.8%) with an anastomotic leak rate of 13.5%. The rate of completeness of mesorectal excision was 90% and the mean number of harvested lymph nodes was 15 (± 9). Using operative time as end-point, the learning curve of rectal cancer robotic surgery identified a cut-off of 57 patients. The technic remained safe with acceptable morbidity and oncological outcomes.

The Position of Circulating Tumor DNA in the Clinical Management of Colorectal Cancer.

Colorectal cancer (CRC) is the third most common cancer type worldwide, with over 1.9 million new cases and 935,000 related deaths in 2020. Within the next decade, the incidence of CRC is estimated to increase by 60% and the mortality by 80%. One of the underlying causes of poor prognosis is late detection, with 60 to 70% of the diagnoses occurring at advanced stages. Circulating cell-free DNA (ccfDNA) is probably the most promising tool for screening, diagnosis, prediction of therapeutic response, and prognosis. More specifically, the analysis of the tumor fraction within the ccfDNA (circulating tumor DNA, ctDNA) has great potential to improve the management of CRC. The present review provides an up-to-date and comprehensive overview of the various aspects related to ctDNA detection in CRC.

Acute Abdominal Complications in Deeply Neutropenic Onco-Hematology Patients: A Retrospective Series of 105 Cases.

BACKGROUND: Acute abdominal complications (AAC) in patients with deep neutropenia (DN) is challenging to manage because of the expected influence of AAC on oncological prognosis and higher surgical complication rate in a period of DN. In practice, these parameters are difficult to appreciate. This study reported our experience in managing these patients. METHODS: All consecutive patients treated in our tertiary care cancer center between 2010 and 2020 who developed AAC in the context of a DN were retrospectively analyzed. AAC was defined as an infection (intra-abdominal, perineal, or cutaneous), bowel obstruction, or intra-abdominal hemorrhage. FINDINGS: Among 105 patients, 18 (17%) required emergent surgery (group 1), 34 patients had a complication requiring surgical oversight (group 2), and 53 patients had a non-surgical etiology (group 3). Fifteen patients underwent surgery in the group 1, three in group 2, and one in group 3. Overall, 28 patients died during hospitalization. Mortality was statistically different between the groups (p = 0·01), with a higher rate in group 1 (n = 9/18, 50%) than in group 2 (n = 11/34, 32%) and group 3 (n = 8/53, 15%). All groups together had a median overall survival (OS) of 14 months and disease-free survival (DFS) of 10 months. OS was not comparable between the groups, and the median length of survival in group 1 was 6 months versus 8 months in group 2 and 23 months in group 3. In group 1, five patients (5/18, 28%) did not relapse at the end of the follow-up compared to 13 in group 2 (13/34, 38%) and 25 in group 3 (25/53, 47%). After discharge, OS and DFS were similar between the groups. INTERPRETATION: The advent of an AAC necessitating surgery in the context of DN is a deadly event associated with a 50% mortality; nonetheless, in case of unpostponable emergencies, surgery can provide long-term survival in selected patients.

Management of Pathogenic CDH1 Variant Carriers Within the FREGAT Network: A Multicentric Retrospective Study.

OBJECTIVE: To describe the management of pathogenic CDH1 variant carriers (pCDH1vc) within the FREGAT (FRench Eso-GAsTric tumor) network. Primary objective focused on clinical outcomes and pathological findings, Secondary objective was to identify risk factor predicting postoperative morbidity (POM). BACKGROUND: Prophylactic total gastrectomy (PTG) remains the recommended option for gastric cancer risk management in pCDH1vc with, however, endoscopic surveillance as an alternative. METHODS: A retrospective observational multicenter study was carried out between 2003 and 2021. Data were reported as median (interquartile range) or as counts (proportion). Usual tests were used for univariate analysis. Risk factors of overall and severe POM (ie, Clavien-Dindo grade 3 or more) were identified with a binary logistic regression. RESULTS: A total of 99 patients including 14 index cases were reported from 11 centers. Median survival among index cases was 12.0 (7.6-16.4) months with most of them having peritoneal carcinomatosis at diagnosis (71.4%). Among the remaining 85 patients, 77 underwent a PTG [median age=34.6 (23.7-46.2), American Society of Anesthesiologists score 1: 75%] mostly via a minimally invasive approach (51.9%). POM rate was 37.7% including 20.8% of severe POM, with age 40 years and above and low-volume centers as predictors ( P =0.030 and 0.038). After PTG, the cancer rate on specimen was 54.5% (n=42, all pT1a) of which 59.5% had no cancer detected on preoperative endoscopy (n=25). CONCLUSIONS: Among pCDH1vc, index cases carry a dismal prognosis. The risk of cancer among patients undergoing PTG remained high and unpredictable and has to be balanced with the morbidity and functional consequence of PTG.

Prognostic Value of Fusobacterium nucleatum after Abdominoperineal Resection for Anal Squamous Cell Carcinoma.

Main prognostic factors of anal squamous cell carcinoma (ASCC) are tumor size, differentiation, lymph node involvement, and male gender. However, they are insufficient to predict relapses after exclusive radiotherapy (RT) or chemoradiotherapy (CRT). Fusobacterium nucleatum has been associated with poor prognosis in several digestive cancers. In this study, we assessed the association between intratumoral F. nucleatum load and clinico-pathological features, relapse, and survival in patients with ASCC who underwent abdominoperineal resection (APR) after RT/CRT. We retrospectively analyzed surgical samples from a cohort of 166 patients with ASCC who underwent APR. F. nucleatum 16S rRNA gene sequences were quantified using real-time quantitative PCR. We associated F. nucleatum load with classical clinicopathological features, overall survival (OS), disease-free survival (DFS), and metastasis-free survival (MFS) using Cox regression univariate and multivariate analyses. Tumors harboring high loads of F. nucleatum (highest tercile) showed longer OS and DFS (median: not reached vs. 50.1 months, p = 0.01, and median: not reached vs. 18.3 months, p = 0.007, respectively). High F. nucleatum load was a predictor of longer OS (HR = 0.55, p = 0.04) and DFS (HR = 0.50, p = 0.02) in multivariate analysis. High F. nucleatum load is an independent favorable prognostic factor in patients with ASCC who underwent APR.

Circulating tumor DNA (ctDNA) in adjuvant therapy of early stage colon cancer: current status and future perspectives.

BACKGROUND: This article reviews the current knowledge on circulating tumor DNA (ctDNA) in early stage colon cancer and ongoing trials on ctDNA-guided treatment in the adjuvant setting. METHODS: A literature search of Pubmed was performed to identify studies on ctDNA in early stage colon cancer and neoadjuvant or adjuvant treatment. For ongoing trials, we searched clinicaltrials.gov and the Australian New Zealand Clinical Trials Registry (ANZCTR). RESULTS: Several studies show that ctDNA is a strong predictor for recurrence and survival after surgery and adjuvant chemotherapy. The specificity of this marker is extremely high, and the sensitivity is increasing with the development of technology. Recurrences can be detected very early and the analysis can potentially be used to guide neoadjuvant and adjuvant treatment. Ongoing and planned studies are now looking into escalation and de-escalation of therapy according to ctDNA-status after surgery. CONCLUSION: Serial measurement of ctDNA shows great promise as a marker for both prognosis and response to treatment in early colon cancer. Future studies will show whether we can use this analysis for tailoring treatment for patients in the adjuvant and neoadjuvant setting. With improved technology, ctDNA has the potential of becoming a 'game-changer' in the treatment of early stage colon cancers.

What Is the Optimal Elective Colectomy for Splenic Flexure Cancer: End of the Debate? A Multicenter Study From the GRECCAR Group With a Propensity Score Analysis.

BACKGROUND: The optimal elective colectomy in patients with splenic flexure tumor is debated. OBJECTIVE: This study aimed to compare splenic flexure colectomy, left hemicolectomy, and subtotal colectomy for perioperative, histological, and survival outcomes in this setting. DESIGN: This is a multicenter retrospective cohort study. SETTING: Patients diagnosed with nonmetastatic splenic flexure tumor who underwent elective colectomy were included. PATIENTS: Between 2006 and 2014, 313 consecutive patients were operated on in 15 French Research Group of Rectal Cancer Surgery centers. INTERVENTIONS: Propensity score weighting was performed to compare short- and long-term outcomes. MAIN OUTCOME MEASURES: The primary end point was disease-free survival. Secondary end points included overall survival, quality of surgical resection, overall postoperative morbidity, surgical postoperative morbidity, and rate of anastomotic leakage. RESULTS: The most performed surgery was splenic flexure colectomy (59%), followed by subtotal colectomy (23%) and left hemicolectomy (18%). Subtotal colectomy was more often performed by laparotomy compared with splenic flexure colectomy and left hemicolectomy (93% vs 61% vs 56%, p < 0.0001), and was associated with a longer operative time (260 minutes (120-460) vs 180 minutes (68-440) vs 217 minutes (149-480), p < 0.0001). Postoperative morbidity was similar between the 3 groups, but the median length of hospital stay was significantly longer after subtotal colectomy (13 days (5-56) vs 10 (4-175) vs 9 (4-55), p = 0.0007). The median number of harvested lymph nodes was significantly higher after subtotal colectomy compared with splenic flexure colectomy and left hemicolectomy (24 (8-90) vs 15 (1-81) vs 16 (3-52), p < 0.0001). The rate of stage III disease and the number of patients treated by adjuvant chemotherapy were similar between the 3 groups. There was no difference in terms of disease-free survival and overall survival between the 3 procedures. LIMITATIONS: The study was limited by its retrospective design. CONCLUSIONS: In the elective setting, splenic flexure colectomy is safe and oncologically adequate for patients with nonmetastatic splenic flexure tumor. However, given the oncological clearance after splenic flexure colectomy, it seems that the debate is not completely closed. See Video Abstract at http://links.lww.com/DCR/B703. CUL ES LA COLECTOMA ELECTIVA PTIMA PARA EL CNCER DE NGULO ESPLNICO FIN DEL DEBATE UN ESTUDIO MULTICNTRICO DEL GRUPO GRECCAR CON UN ANLISIS DE PUNTAJE DE PROPENSIN: ANTECEDENTES:La colectomía electiva óptima en pacientes con tumores del ángulo esplénico continua en debate.OBJETIVO:Comparar la colectomía de ángulo esplénico, hemicolectomía izquierda y colectomía subtotal para los resultados perioperatorios, histológicos y de supervivencia en este escenario.DISEÑO:Estudio de cohorte retrospectivo multicéntrico.ESCENARIO:Se incluyeron pacientes diagnosticados de tumores del ángulo esplénico no metastásicos que se sometieron a colectomía electiva.PACIENTES:Entre 2006 y 2014, 313 pacientes consecutivos fueron intervenidos en 15 centros GRECCAR.INTERVENCIONES:Se realizó una ponderación del puntaje de propensión para comparar los resultados a corto y largo plazo.PRINCIPALES MEDIDAS DE RESULTADO:El criterio de valoración principal fue la supervivencia libre de enfermedad. Los criterios de valoración secundarios incluyeron la supervivencia general, la calidad de la resección quirúrgica, la morbilidad posoperatoria general, la morbilidad posoperatoria quirúrgica y la tasa de fuga anastomótica.RESULTADOS:La cirugía más realizada fue la colectomía del ángulo esplénico (59%), seguida de la colectomía subtotal (23%) y la hemicolectomía izquierda (18%). La colectomía subtotal se realizó con mayor frecuencia mediante laparotomía en comparación con la colectomía de ángulo esplénico y la hemicolectomía izquierda (93% frente a 61% frente a 56%, p <0.0001), y se asoció con un tiempo quirúrgico más prolongado (260 min [120-460] frente a 180 min [68-440] frente a 217 min [149-480], p <0.0001). La morbilidad posoperatoria fue similar entre los tres grupos, pero la duración media de la estancia hospitalaria fue significativamente más prolongada después de la colectomía subtotal (13 días [5-56] frente a 10 [4-175] frente a 9 [4-55], p = 0.0007). La mediana del número de ganglios linfáticos extraídos fue significativamente mayor después de la colectomía subtotal en comparación con la colectomía del ángulo esplénico y la hemicolectomía izquierda (24 [8-90] frente a 15 [1-81] frente a 16 [3-52], p <0.0001). La tasa de enfermedad en estadio III y el número de pacientes tratados con quimioterapia adyuvante fueron similares entre los 3 grupos. No hubo diferencias en términos de supervivencia libre de enfermedad y supervivencia general entre los 3 procedimientos.LIMITACIONES:El estudio estuvo limitado por su diseño retrospectivo.CONCLUSIONES:En un escenario electivo, la colectomía del ángulo esplénico es segura y oncológicamente adecuada para pacientes con tumores del ángulo esplénico no metastásicos. Sin embargo, dado el aclaramiento oncológico tras la colectomía del ángulo esplénico, parece que el debate no está completamente cerrado. Consulte Video Resumen en http://links.lww.com/DCR/B703.

Circulating tumor DNA is a prognostic marker of tumor recurrence in stage II and III colorectal cancer: multicentric, prospective cohort study (ALGECOLS).

BACKGROUND: In non-metastatic colorectal cancer (CRC), we evaluated prospectively the pertinence of longitudinal detection and quantification of circulating tumor DNA (ctDNA) as a prognostic marker of recurrence. METHOD: The presence of ctDNA was assessed from plasma collected before and after surgery for 184 patients classified as stage II or III and at each visit during 3-4 years of follow-up. The ctDNA analysis was performed by droplet-based digital polymerase chain reaction, targeting mutation and methylation markers, blindly from the clinical outcomes. Multivariate analyses were adjusted on age, gender, stage, and adjuvant chemotherapy. RESULTS: Before surgery, 27.5% of patients were positive for ctDNA detection. The rate of recurrence was 32.7% and 11.6% in patients with or without detectable ctDNA respectively (P = 0.001). Time to recurrence (TTR) was significantly shorter in patients with detectable ctDNA before (adjusted hazard ratio [HR] = 3.58, 95% confidence interval [CI] 1.71-7.47) or immediately after surgery (adjusted HR = 3.22, 95% CI 1.32-7.89). The TTR was significantly shorter in patients with detectable ctDNA during the early postoperative follow-up (1-6 months) (adjusted HR = 5, 95% CI 1.9-12.9). Beyond this period, ctDNA remained a prognostic marker with a median anticipated diagnosis of recurrence of 13.1 weeks (interquartile range 28 weeks) when compared to imaging follow-up. The rate of ctDNA+ might be underestimated knowing that consensus pre-analytical conditions were not described at initiation of the study. CONCLUSION: This prospective study confirms the relevance of ctDNA as a recurrence risk factor in stage II and III CRC before surgery and as a marker of minimal residual disease after surgery that may predict recurrence several months before imaging techniques.

Characterization of Plasma Cell-Free DNA Integrity Using Droplet-Based Digital PCR: Toward the Development of Circulating Tumor DNA-Dedicated Assays.

Background: Cellular-cell free-DNA (ccfDNA) is being explored as a diagnostic and prognostic tool for various diseases including cancer. Beyond the evaluation of the ccfDNA mutational status, its fragmentation has been investigated as a potential cancer biomarker in several studies. However, probably due to a lack of standardized procedures dedicated to preanalytical and analytical processing of plasma samples, contradictory results have been published. Methods: ddPCR assays allowing the detection of KRAS wild-type and mutated sequences (KRAS p.G12V, pG12D, and pG13D) were designed to target different fragments sizes. Once validated on fragmented and non-fragmented DNA extracted from cancer cell lines, these assays were used to investigate the influence of the extraction methods on the non-mutated and mutated ccfDNA integrity reflected by the DNA integrity index (DII). The DII was then analyzed in two prospective cohorts of metastatic colorectal cancer patients (RASANC study n = 34; PLACOL study n = 12) and healthy subjects (n = 49). Results and Discussion: Our results demonstrate that ccfDNA is highly fragmented in mCRC patients compared with healthy individuals. These results strongly suggest that the characterization of ccfDNA integrity hold great promise toward the development of a universal biomarker for the follow-up of mCRC patients. Furthermore, they support the importance of standardization of sample handling and processing in such analysis.

Long-Term Results after Surgical Resection of Peritoneal Metastasis from Neuroendocrine Tumors.

INTRODUCTION: Peritoneal metastases from neuroendocrine tumors are associated with a bad prognosis. The objective of our study was to evaluate whether surgical resection could lead to prolonged survival in selected patients. This survival was compared to that of patients operated for liver metastasis. METHODS: From our prospectively maintained database we included 88 patients who underwent the complete resection of peritoneal and/or liver metastasis between January 1995 and December 2016 in Gustave-Roussy. Three resection groups were compared: peritoneal metastasis alone, liver metastasis alone, and the combined resection of liver and peritoneal metastases. RESULTS: The median peritoneal cancer index was 10 in the peritoneal group and 11 in the peritoneal + liver group. The 5-year overall survival was 81% (60-100) in the peritoneal group compared to 78% (65.2-92.8) in the liver group, and 72% (58.7-89.7) in the peritoneal + liver group (p = 0.71). The 3-year disease-free survival reached 26.9% (16.1-45.1) in the liver group, 12.5% (2.3-68.2) in the peritoneal group, and 32.4% (19.9-52.6) in the combined liver + peritoneal group (p = 0.45). In the univariate analysis, the prognosis factors for a longer survival were: small bowel primary tumor origin, low preoperative chromogranin A level, and tumor grade ≤1. CONCLUSION: Despite a high recurrence rate, long-term overall survival can be achieved after the resection of peritoneal metastasis in selected patients. This survival is comparable to that of patients operated for liver metastasis only. Surgery should stand as a standard treatment for peritoneal metastases in patients with resectable disease.

"Decision for adjuvant treatment in stage II colon cancer based on circulating tumor DNA:The CIRCULATE-PRODIGE 70 trial".

BACKGROUND: Adjuvant treatment for stage II colon cancer remains debated. Finding a tool to select patients at risk for disease recurrence may help the clinical decision. Circulating tumor DNA (ctDNA) has been reported recently as a potential predictive marker for disease recurrence. We thus aim to test its ability to better select stage II colon cancer patients for adjuvant therapy. METHODS: This national, phase III trial (NCT00002019-000935-15) conducted in more than 100 centers in France, plans to screen around 2640 patients in order to randomize (2:1; minimization method) 198 ctDNA positive patients. Patients aged 18 to 75 years with ECOG performance status ≤1 with R0 surgical resection of a pT3-T4aN0 colon or high rectum adenocarcinoma will be randomized within 63 days after curative-intent surgery, to adjuvant mFOLFOX6 (oxaliplatin 85 mg/m², leucovorin 400 mg/m², and 5-FU bolus 400 mg/m2 then 5FU Continuous infusion 2.4 g/m²) every two weeks for 12 cycles or observation. Patients will be followed for maximum 7 years. A gain of 17.5% in 3-yr disease free survival (DFS) is expected (42.5% in the experimental arm vs. 25% in the control arm; HR:0.62; α, 5% [two-sided log-rank test]; 1-ß, 80%). Secondary endpoints include 2-yr DFS, overall survival, and toxicity. Recruitement began End of January 2020.

Metastatic colorectal cancer (mCRC): French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, SFR).

INTRODUCTION: This document is a summary of the French intergroup guidelines regarding the management of metastatic colorectal cancer (mCRC) published in January 2019, and available on the French Society of Gastroenterology website (SNFGE) (www.tncd.org). METHODS: This collaborative work was realized by all French medical and surgical societies involved in the management of mCRC. Recommendations are graded in three categories (A, B and C), according to the level of evidence found in the literature, up until December 2018. RESULTS: The management of metastatic colorectal cancer has become complex because of increasing available medical, radiological and surgical treatments alone or in combination. The therapeutic strategy should be defined before the first-line treatment, mostly depending on the presentation of the disease (resectability of the metastases, symptomatic and/or threatening disease), of the patient's condition (ECOG PS, comorbidities), and tumor biology (RAS, BRAF, MSI). The sequence of targeted therapies also seems to have an impact on the outcome (angiogenesis inhibition beyond progression). Surgical resection of metastases was the only curative intent treatment to date, joined recently by percutaneous tumor ablation tools (radiofrequency, microwave). Localized therapies such as hepatic intra-arterial infusion, radioembolization and hyperthermic intraperitoneal chemotherapy, also have seen their indications specified (liver-dominant disease and resectable peritoneal carcinomatosis). New treatments have been developed in heavily pretreated patients, increasing overall survival and preserving quality of life (regorafenib and trifluridine/tipiracil). Finally, immune checkpoint inhibitors have demonstrated high efficacy in MSI mCRC. CONCLUSION: French guidelines for mCRC management are put together to help offer the best personalized therapeutic strategy in daily clinical practice, as the mCRC therapeutic landscape is complexifying. These recommendations are permanently being reviewed and updated. Each individual case must be discussed within a multidisciplinary team (MDT).

Survival after complete cytoreductive surgery and HIPEC for extensive pseudomyxoma peritonei.

INTRODUCTION: The optimal treatment for pseudomyxoma peritonei (PMP) combines complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Yet, achieving CRS is challenging in the case of extensive involvement of the peritoneal cavity and the survival benefit in this setting remains uncertain. The present study evaluated the surgical outcomes according to the peritoneal extent. METHODS: Between 1992 and 2014, 245 patients underwent CRS and HIPEC for PMP in our institution. Their characteristics were reviewed using a prospective database. Extensive PMP was defined as a peritoneal cancer index (PCI) ≥ 28. Sixty-one patients with extensive PMP were compared to 184 with non-extensive PMP. RESULTS: Severe complications were more frequent in the extensive group (46% vs. 23%, p < 0.001) but the post-operative mortality was not significantly different (8% vs. 3%, p = 0.1). The 5-year disease-free survival reached 45% in the extensive and 78% in the non-extensive group (p < 0.0001). The 5-year overall survival was 70% and 90% in the extensive and non-extensive group respectively (p < 0.021). CONCLUSION: CRS with HIPEC offers prolonged survival even in the case of extensive PMP. Because of the high rate of surgical morbidity in the extensive group, patients should be carefully selected.

Strategies for Managing Intraoperative Discovery of Limited Colorectal Peritoneal Metastases.

BACKGROUND: Management of limited synchronous colorectal peritoneal metastases (CRPM) is critical to outcome. Resection of the primary tumor and CRPM can be performed concurrently, followed by hyperthermic intraperitoneal chemotherapy (HIPEC) either immediately, during the same procedure (one-stage), or during a systematic second-stage procedure (two-stage). OBJECTIVE: The aim of this study was to compare these two strategies for morbidity, mortality, and survival. METHODS: All patients presenting with limited (initial Peritoneal Cancer Index [PCI] ≤ 10) synchronous CRPM who had undergone complete cytoreductive surgery plus HIPEC between 2000 and 2016 were selected from a prospectively maintained institutional database. RESULTS: Overall, 74 patients were included-31 in the one-stage group and 43 in the two-stage group. During second-stage surgery, a peritoneal recurrence was diagnosed in 37 (86%) patients, 12 of whom had a PCI > 10 (28%) and 2 of whom had unresectable disease (5%). Among the one-stage group, peritoneal recurrence occurred in 29% of patients after a median delay of 23 months. Overall survival at 1, 3, and 5 years was similar between the two groups, i.e. 96%, 59%, and 51% for the one-stage group, and 98%, 77%, and 61% for the two-stage group. A PCI > 10 at the time of HIPEC, as well as liver metastases, were independent negative prognostic factors. CONCLUSIONS: For incidental limited CRPM diagnosed during primary tumor resection, one-stage curative treatment is preferable, avoiding a supplementary surgical procedure. Given the critical issues associated with completeness of resection, patients should be referred to centers specialized in peritoneal surgery.

Postoperative hepatic arterial chemotherapy in high-risk patients as adjuvant treatment after resection of colorectal liver metastases - a randomized phase II/III trial - PACHA-01 (NCT02494973).

BACKGROUND: After curative-intent surgery for colorectal liver metastases (CRLM), liver recurrence occurs in more than 60% of patients, despite the administration of perioperative or adjuvant chemotherapy. This risk is even higher after resection of more than three CRLM. As CRLM are mostly supplied by arterial blood flow, hepatic arterial infusion (HAI) of chemotherapeutic agents after resection of CRLM is an attractive approach. Oxaliplatin-based HAI chemotherapy, in association with systemic fluoropyrimidines, has been shown to be safe and highly active in patients with CRLM. In a retrospective series of 98 patients at high risk of hepatic recurrence (≥4 resected CRLM), adjuvant HAI oxaliplatin combined with systemic chemotherapy was feasible and significantly improved disease-free survival compared to adjuvant, 'modern' systemic chemotherapy alone. METHODS/DESIGN: This study is designed as a multicentre, randomized, phase II/III trial. The first step is a non-comparative randomized phase II trial (power, 95%; one-sided alpha risk, 10%). Patients will be randomly assigned in a 1:1 ratio to adjuvant systemic FOLFOX (control arm) or adjuvant HAI oxaliplatin plus systemic LV5FU2 (experimental arm). A total 114 patients will need to be included. The main objective of this trial is to evaluate the potential survival benefit of adjuvant HAI with oxaliplatin after resection of at least 4 CRLM (primary endpoint: 18-month hepatic recurrence-free survival rate). We also aim to assess the feasibility of delivering at least 4 cycles of HAI (or i.v.) oxaliplatin after surgical treatment of at least 4 CRLM, the toxicity (NCI-CTC v4.0) of adjuvant HAI plus systemic chemotherapy, including HAI catheter-related complications, compared to systemic chemotherapy alone, and the efficacy of adjuvant HAI on hepatic and extra-hepatic recurrence-free (survival and overall survival). DISCUSSION: If 18-month hepatic recurrence-free survival is greater than 50% in the experimental arm, the study will be pursued in phase III, for which the primary endpoint will be 3-year recurrence-free survival rate. Patients randomized in the phase II will be included in the phase III, with an additional number of 106 patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02494973 . Trial registration date: July 10, 2015.

Peritoneal and extraperitoneal relapse after previous curative treatment of peritoneal metastases from colorectal cancer: What survival can we expect?

INTRODUCTION: Over the last 20 years, complete cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) dramatically increased the survival of patients with colorectal peritoneal metastases (CRPM). However, despite better knowledge of the disease, around 70% of patients relapse after CRS with HIPEC. This study was designed to analyse the pattern of recurrence and the outcomes of different treatment modalities. METHODS: Patients relapsing after CRS plus HIPEC for CRPM were selected from a prospective database. The impact of iterative curative-intent treatments was analysed using Kaplan-Meier estimates and multivariate Cox regression models. RESULTS: Between April 1993 and December 2014, 190 of 274 (69%) patients previously treated by CRS plus HIPEC developed relapse, as an isolated peritoneal recurrence (31%), isolated distant recurrence (35%), or multisite recurrence (34%). The curative-intent treatment rate was 48% for isolated peritoneal recurrences, 49% for isolated distant recurrences and 22% for multisite recurrences (p = 0.002). From the diagnosis of relapse, 3- and 5-year overall survival were 77% and 46% after curative-intent treatment and 14% and 4.7% after non-curative treatment, with median survival of 59.7 and 18.3 months (log-rank p < 0.0001), respectively. Regression analysis identified the initial extent of CRPM (hazard ratio [HR]: 2.25; p < 0.0001), iterative curative-intent treatment (HR: 0.22; p < 0.0001) and disease-free interval (HR: 1.77; p = 0.01) as independent predictors of prolonged survival. CONCLUSIONS: Iterative curative-intent treatment can be performed in up to 40% of patients with relapse after CRS and HIPEC for CRPM, and is associated with prolonged survival in selected patients.

Peritoneal Metastases from Colorectal Cancer: Treatment Principles and Perspectives.

Peritoneal metastases are the third most common site of recurrence of colorectal cancer. Diagnosis is difficult and often made at an advanced stage even on imaging. Curative treatment relies on complete cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (HIPEC), which dramatically improves survival in selected patients. Main prognostic factors are based on the extent of the peritoneal disease and the completeness of surgery. Therefore, identifying patients at high risk of developing peritoneal metastases with the aim of diagnosing and treating patients at an early stage appears crucial. Proactive attitude and prophylactic treatment based on HIPEC are being evaluated on clinical trials.