External multicentre validation of pseudomyxoma peritonei PSOGI-Ki67 classification.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare malignant disease. Adding of the Ki67 proliferation index to the PSOGI PMP classification provided two different subcategories of the extensive HG-PMP group (HG-PMP ≤15% and HG-PMP >15%) with different survival in a previous unicentric study. This study aims to carry out an external and multicentre validation of this new proposed classification. METHOD: It was a prospective analysis of samples from a historical and international cohort of patients. A representative area with higher cellular density was used to determine the Ki67%. The Ki67 proliferation index (%) was determined in all the HG-PMP patients. A Cox proportional hazard models and multivariable COX models were used. The Kaplan-Meier method and the two-tailed log-rank test were used to analyse the effect of different PSOGI-Ki67 categories on OS and DFS. Its predictive accuracy was analysed using Harrel's C-index and the ROC curve. The calibration was performed using the calibration plots matching. RESULTS: After exclusions, 349 patients were available for analysis. The 5-years OS were 86% for LG-PMP, 59% for HG-PMP≤15, 38% for HG-PMP>15 and 42% for SRC-PMP (p = 0.0001). The 5-years DFS were 49% for LG-PMP, 35% for HG-PMP≤15, 16% for HG-PMP>15 and 18% SRC-PMP (p = 0.0001). The discrimination capability of PSOGI-Ki67 was validated. CONCLUSION: the PSOGI-Ki67 classification discriminates and predicts the OS and DFS in patients with PMP dividing the HG-PMP category into two well-defined sub-categories. The Ki67 proliferation index should be incorporated routinely in the pathology report for these patients.

Prognosis of poorly cohesive gastric cancer after complete cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy (CYTO-CHIP study).

BACKGROUND: The incidence of gastric poorly cohesive carcinoma (PCC) is increasing. The prognosis for patients with peritoneal metastases remains poor and the role of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is controversial. The aim was to clarify the impact of gastric PCC with peritoneal metastases treated by CRS with or without HIPEC. METHODS: All patients with peritoneal metastases from gastric cancer treated with CRS with or without HIPEC, in 19 French centres, between 1989 and 2014, were identified from institutional databases. Clinicopathological characteristics and outcomes were compared between PCC and non-PCC subtypes, and the possible benefit of HIPEC was assessed. RESULTS: In total, 277 patients were included (188 PCC, 89 non-PCC). HIPEC was performed in 180 of 277 patients (65 per cent), including 124 of 188 with PCC (66 per cent). Median overall survival (OS) was 14.7 (95 per cent c.i. 12.7 to 17.3) months in the PCC group versus 21.2 (14.7 to 36.4) months in the non-PCC group (P < 0.001). In multivariable analyses, PCC (hazard ratio (HR) 1.51, 95 per cent c.i. 1.01 to 2.25; P = 0.044) was associated with poorer OS, as were pN3, Peritoneal Cancer Index (PCI), and resection with a completeness of cytoreduction score of 1, whereas HIPEC was associated with improved OS (HR 0.52; P < 0.001). The benefit of CRS-HIPEC over CRS alone was consistent, irrespective of histology, with a median OS of 16.7 versus 11.3 months (HR 0.60, 0.39 to 0.92; P = 0.018) in the PCC group, and 34.5 versus 14.3 months (HR 0.43, 0.25 to 0.75; P = 0.003) in the non-PCC group. Non-PCC and HIPEC were independently associated with improved recurrence-free survival and fewer peritoneal recurrences. In patients who underwent HIPEC, PCI values of below 7 and less than 13 were predictive of OS in PCC and non-PCC populations respectively. CONCLUSION: In selected patients, CRS-HIPEC offers acceptable outcomes among those with gastric PCC and long survival for patients without PCC.

Nosocomial infection with SARS-Cov-2 within Departments of Digestive Surgery.

INTRODUCTION: The COVID-19 pandemic imposed a drastic reduction in surgical activity in order to respond to the influx of hospital patients and to protect uninfected patients by avoiding hospitalization. However, little is known about the risk of infection during hospitalization or its consequences. The aim of this work was to report a series of patients hospitalized on digestive surgery services who developed a nosocomial infection with SARS-Cov-2 virus. METHODS: This is a non-interventional retrospective study carried out within three departments of digestive surgery. The clinical, biological and radiological data of the patients who developed a nosocomial infection with SARS-Cov-2 were collected from the computerized medical record. RESULTS: From March 1, 2020 to April 5, 2020, among 305 patients admitted to digestive surgery departments, 15 (4.9%) developed evident nosocomial infection with SARS-Cov-2. There were nine men and six women, with a median age of 62 years (35-68 years). All patients had co-morbidities. The reasons for hospitalization were: surgical treatment of cancer (n=5), complex emergencies (n=5), treatment of complications linked to cancer or its treatment (n=3), gastroplasty (n=1), and stoma closure (n=1). The median time from admission to diagnosis of SARS-Cov-2 infection was 34 days (5-61 days). In 12 patients (80%), the diagnosis was made after a hospital stay of more than 14 days (15-63 days). At the end of the follow-up, two patients had died, seven were still hospitalized with two of them on respiratory assistance, and six patients were discharged post-hospitalization. CONCLUSIONS: The risk of SARS-Cov-2 infection during hospitalization or following digestive surgery is a real and potentially serious risk. Measures are necessary to minimize this risk in order to return to safe surgical activity.

[Nosocomial infection with SARS-Cov-2 within departments of digestive surgery]. / Infection nosocomiale à SARS-Cov-2 dans les services de chirurgie digestive.

INTRODUCTION: The COVID-19 pandemic imposed a drastic reduction in surgical activity in order to respond to the influx of hospital patients and to protect uninfected patients by avoiding hospitalization. However, little is known about the risk of infection during hospitalization or its consequences. The aim of this work was to report a series of patients hospitalized on digestive surgery services who developed a nosocomial infection with SARS-Cov-2 virus. METHODS: This is a non-interventional retrospective study carried out within three departments of digestive surgery. The clinical, biological and radiological data of the patients who developed a nosocomial infection with SARS-Cov-2 were collected from the computerized medical record. RESULTS: From March 1, 2020 to April 5, 2020, among 305 patients admitted to digestive surgery departments, 15 (4.9 %) developed evident nosocomial infection with SARS-Cov-2. There were nine men and six women, with a median age of 62 years (35-68 years). All patients had co-morbidities. The reasons for hospitalization were: surgical treatment of cancer (n = 5), complex emergencies (n = 5), treatment of complications linked to cancer or its treatment (n = 3), gastroplasty (n = 1), and stoma closure (n = 1). The median time from admission to diagnosis of SARS-Cov-2 infection was 34 days (5-61 days). In 12 patients (80%), the diagnosis was made after a hospital stay of more than 14 days (15-63 days). At the end of the follow-up, two patients had died, seven were still hospitalized with two of them on respiratory assistance, and six patients were discharged post-hospitalization. CONCLUSIONS: The risk of SARS-Cov-2 infection during hospitalization or following digestive surgery is a real and potentially serious risk. Measures are necessary to minimize this risk in order to return to safe surgical activity.

Development and internal validation of a diagnostic score for gastric linitis plastica.

BACKGROUND: There is no consensual definition for gastric linitis plastica (GLP). We aim to construct a diagnostic score to distinguish this rare tumor from usual gastric adenocarcinomas. METHODS: In this retrospective study, all patients who had gastrectomy for cancer between 2007 and 2017 in French tertiary centers were included. The outcome was a diagnosis of GLP based on pathological review of the surgical specimen. The diagnostic score was created by using variables that were most frequently associated with GLP using penalized logistic regression on multiply imputed datasets. We used discrimination measures to assess the performances of the score. Internal validation was performed using bootstrapping methods to correct for over-optimism. RESULTS: 220 patients including 71 linitis plastica (female 49%, median age 57 years) were analyzed. The six parameters retained in the diagnosis score were the presence of large folds and/or parietal thickening on at least one segment, pangastric infiltration and presence of gastric stenosis on the upper endoscopy, circumferential thickening on at least one segment and thickening of the third hyperechogenic layer on endoscopic ultrasound and the presence of signet ring cells on endoscopic biopsies. The area under the ROC curve (AUC) was 0.967 with a sensitivity of 94% [89.9-97.3] and a specificity of 88.7% [81.7-95.8] for a threshold of 2.75. After internal validation, the corrected AUC was 0.959. CONCLUSION: It is the first study validating a pre-therapeutic diagnostic score (Saint Louis linitis score) with an excellent ability to discriminate GLP from non-GLP adenocarcinomas. An external validation is necessary to confirm our data.

Elective surgery for tumours of the splenic flexure: a French inter-group (AFC, SFCD, FRENCH, GRECCAR) survey.

BACKGROUND: In an elective setting, there is no consensus regarding the type of colectomy that is best for patients with tumors of the splenic flexure: segmental left colectomy (or splenic flexure colectomy), left hemicolectomy or subtotal colectomy (or extended right hemicolectomy). In the United Kingdom, extended right hemicolectomy is preferred by surgeons. The aim of the present survey was to report on the practices in France for this particular tumor location. METHODS: Between 15/07/17 and 15/10/17, members of two French surgical societies [the French Association of Surgery (AFC) and the French Society of Digestive Surgery (SFCD)] and two French surgical cooperative groups [the French Federation of Surgical Research (FRENCH) and the French Research Group of Rectal Cancer Surgery (GRECCAR)] were solicited by email to answer an online anonymous questionnaire. RESULTS: A total of 190 out of 420 surgeons participated in this study (response rate 45%). The preferred procedure was splenic flexure colectomy (70%), followed by left hemicolectomy (17%) and subtotal colectomy (13%). The most used surgical approach was laparoscopy (63%), followed by laparotomy (31%) and hand-assisted laparoscopy (6%). Lymph node dissection was extended to the middle colic artery in 29% of splenic flexure colectomies and in 33% of left hemicolectomies. Twenty-nine percent of responders thought that tumors of the splenic flexure had a worse prognosis in comparison with other colonic sites, because of insufficient lymph node dissection (73%) or a more advanced stage (50%) at diagnosis. However, this opinion did not change the type of colectomy performed. CONCLUSIONS: There is a strong consensus in France to operate tumors of the splenic flexure with a splenic flexure colectomy and lymph node dissection limited to the left colic artery.

Multicentre study of perioperative versus adjuvant chemotherapy for resectable colorectal liver metastases.

Background: It is not known whether perioperative chemotherapy, compared with adjuvant chemotherapy alone, improves disease-free survival (DFS) in patients with upfront resectable colorectal liver metastases (CLM). The aim of this study was to estimate the impact of neoadjuvant 5-fluorouracil, leucovorin and oxaliplatin (FOLFOX) on DFS in patients with upfront resectable CLM. Methods: Consecutive patients who presented with up to five resectable CLM at two Japanese and two French centres in 2008-2015 were included in the study. Both French institutions favoured perioperative FOLFOX, whereas the two Japanese groups systematically preferred upfront surgery plus adjuvant chemotherapy. Inverse probability of treatment weighting (IPTW) and Cox regression multivariable models were used to adjust for confounding. The primary outcome was DFS. Results: Some 300 patients were included: 151 received perioperative chemotherapy and 149 had upfront surgery plus adjuvant chemotherapy. The weighted 3-year DFS rate was 33·5 per cent after perioperative chemotherapy compared with 27·1 per cent after upfront surgery plus adjuvant chemotherapy (hazard ratio (HR) 0·85, 95 per cent c.i. 0·62 to 1·16; P = 0·318). For the subgroup of 165 patients who received adjuvant FOLFOX successfully (for at least 3 months), the adjusted effect of neoadjuvant chemotherapy was not significant (HR 1·19, 0·74 to 1·90; P = 0·476). No significant effect of neoadjuvant chemotherapy was observed in multivariable regression analysis. Conclusion: Compared with adjuvant chemotherapy, perioperative FOLFOX does not improve DFS in patients with resectable CLM, provided adjuvant chemotherapy is given successfully.

Antecedentes: Se desconoce si la quimioterapia perioperatoria en comparación con la quimioterapia adyuvante sola mejora la supervivencia libre de enfermedad (disease­free survival, DFS) en pacientes con metástasis hepáticas de origen colorrectal (colorectal liver metastases, CLM) resecables de inicio. El objetivo de este estudio fue estimar el impacto de la neoadyuvancia con 5­fluorouracilo, leucovorina y oxaliplatino (FOLFOX) sobre la DFS en pacientes con CLM resecables desde el principio. Métodos: Se incluyeron pacientes consecutivos que presentaban hasta cinco CLM resecables en dos centros japoneses y dos centros franceses entre 2008 a 2015. Ambas instituciones francesas favorecían FOLFOX perioperatorio, mientras que los dos grupos japoneses utilizaban sistemáticamente la cirugía de entrada y quimioterapia adyuvante. Se utilizaron la probabilidad inversa del tratamiento ponderado (Inverse Probability of Treatment Weighting, IPTW) y el modelo multivariable de regresión de Cox para ajustar por factores de confusión. El resultado primario fue la DFS. Resultados: Se incluyeron 300 pacientes (grupo de quimioterapia perioperatoria n = 151 y grupo de cirugía de entrada más quimioterapia adyuvante n = 149). La DFS a los 3 años ponderada fue del 33% después de quimioterapia perioperatoria versus 27% tras cirugía de entrada (cociente de riesgos instantáneos, hazard ratio HR: 0,85; i.c. del 95% (0,62­1,16); P = 0,32). Cuando se consideró el subgrupo de pacientes que (n = 165) de manera efectiva (al menos 3 meses) recibieron FOLFOX adyuvante, el efecto ajustado de la quimioterapia neoadyuvante no fue significativo (HR: 1,19 (0,74­1,90); P = 0,48). No se observó un efecto significativo de la quimioterapia neoadyuvante en el análisis de regresión multivariable. Conclusión: En comparación con la quimioterapia adyuvante, el FOLFOX perioperatorio no mejora la DFS en CLM resecables siempre y cuando la quimioterapia adyuvante se administre de forma efectiva.

Management of colorectal peritoneal metastases: Expert opinion.

When peritoneal metastases are diagnosed (strong agreement of experts): (i) seek advice from a multidisciplinary coordination meeting (MCM) with large experience in peritoneal disease (e.g. BIG RENAPE network); (ii) transfer (or not) the patient to a referral center with experience in hyperthermic intraperitoneal chemotherapy (HIPEC), according to the advice of the MCM. With regard to systemic chemotherapy (strong agreement of experts): (i) it should be performed both before and after surgery, (ii) for no longer than 6 months; (iii) without postoperative anti-angiogenetic drugs. With regard to cytoreductive surgery (strong agreement of experts): (i) Radical surgery requires a xiphopubic midline incision; (ii) no cytoreductive surgery via laparoscopy. With regard to HIPEC: HIPEC can be proposed for trials outside an HIPEC referral center (weak agreement between experts): (i) if surgery is radical; (ii) if the expected morbidity is "reasonable"; (iii) if the indication for HIPEC was suggested by a MCM, and; (iv) mitomycin is preferred to oxaliplatin (which cannot be recommended) for this indication.

Secondary technical resectability of colorectal cancer liver metastases after chemotherapy with or without selective internal radiotherapy in the randomized SIRFLOX trial.

BACKGROUND: Secondary resection of initially unresectable colorectal cancer liver metastases (CRLM) can prolong survival. The added value of selective internal radiotherapy (SIRT) to downsize lesions for resection is not known. This study evaluated the change in technical resectability of CRLM with the addition of SIRT to FOLFOX-based chemotherapy. METHODS: Baseline and follow-up hepatic imaging of patients who received modified FOLFOX (mFOLFOX6: fluorouracil, leucovorin, oxaliplatin) chemotherapy with or without bevacizumab (control arm) versus mFOLFOX6 (with or without bevacizumab) plus SIRT using yttrium-90 resin microspheres (SIRT arm) in the phase III SIRFLOX trial were reviewed by three or five (of 14) expert hepatopancreatobiliary surgeons for resectability. Reviewers were blinded to one another, treatment assignment, extrahepatic disease status, and information on clinical and scanning time points. Technical resectability was defined as at least 60 per cent of reviewers (3 of 5, or 2 of 3) assessing a patient's liver metastases as surgically removable. RESULTS: Some 472 patients were evaluable (SIRT, 244; control, 228). There was no significant baseline difference in the proportion of technically resectable liver metastases between SIRT (29, 11·9 per cent) and control (25, 11·0 per cent) arms (P = 0·775). At follow-up, significantly more patients in both arms were deemed technically resectable compared with baseline: 159 of 472 (33·7 per cent) versus 54 of 472 (11·4 per cent) respectively (P = 0·001). More patients were resectable in the SIRT than in the control arm: 93 of 244 (38·1 per cent) versus 66 of 228 (28·9 per cent) respectively (P < 0·001). CONCLUSION: Adding SIRT to chemotherapy may improve the resectability of unresectable CRLM.

ANTECEDENTES: La resección secundaria de metástasis hepáticas de cáncer colorrectal (colorectal cancer liver metastases, CRLM) inicialmente irresecables puede prolongar la supervivencia. Se desconoce el valor añadido de la radioterapia interna selectiva (selective internal radiation therapy, SIRT). Este estudio evaluó el cambio en la resecabilidad técnica de las CRLM secundario a la adición de SIRT a una quimioterapia tipo FOLFOX. MÉTODOS: Las pruebas de radioimagen basales y durante el seguimiento de pacientes tratados con un régimen FOLFOX modificado (mFOLFOX6: fluorouracilo, leucovorina, oxaliplatino) ± bevacizumab (grupo control) versus mFOLFOX6 (± bevacizumab) más SIRT usando microesferas de resina de yttrium-90, en el ensayo de fase III SIRFLOX, fueron revisadas por 3-5 (de 14) cirujanos expertos hepatobiliares para determinar la resecabilidad. Los expertos efectuaron la revisión de forma ciega unos respecto a otros en relación con la asignación al tratamiento, estado de la enfermedad extra-hepática y situación clínica en el momento del estudio radiológico. La resecabilidad técnica se definió como ≥ 60% de revisores evaluando las metástasis del paciente como quirúrgicamente resecables. RESULTADOS: Fueron evaluables un total de 472 pacientes (control, n = 228; SIRT, n = 244). No hubo diferencias significativas basales en la proporción de metástasis hepáticas técnicamente resecables entre SIRT (29/244; 11,9%) y el grupo control (25/228; 11,0%: P = 0,775). Durante el seguimiento y en ambos brazos de tratamiento, un número significativamente mayor de pacientes se consideraron técnicamente resecables en comparación con la situación basal (54/472 (11,4%) basal y 159/472 (33,7%) al seguimiento). Hubo más pacientes resecables en el grupo SIRT que en el control (93/244 (38,1%) y 66/228 (28,9%); P < 0,001, respectivamente). CONCLUSIÓN: La adición de SIRT a la quimioterapia puede mejorar la resecabilidad de las CRLM irresecables.

Recurrence of pseudomyxoma peritonei after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Background: Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by mucinous ascites, typically related to appendiceal or ovarian tumours. Current standard treatment involves cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but recurrences occur in 20-30 per cent of patients. The aim of this study was to define the timing and patterns of recurrence to provide a basis for modifying follow-up of these patients. Methods: This observational study examined a prospectively developed multicentre national database (RENAPE working group) to identify patients with recurrence after optimal CRS and HIPEC for PMP. Postoperative complications, long-term outcomes and potential prognostic factors were evaluated. Results: Of 1411 patients with proven PMP, 948 were identified who had undergone curative CRS and HIPEC. Among these patients, 229 first recurrences (24·2 per cent) were identified: 196 (20·7 per cent) occurred within the first 5 years (early recurrence) and 30 (3·2 per cent) occurred between 5 and 10 years. Three patients developed a first recurrence more than 10 years after the original treatment. The mean(s.d.) time to first recurrence was 2·36(2·21) years. Preoperative chemotherapy and high-grade pathology were significant factors for early recurrence. Overall survival for the entire group was 77·9 and 63·1 per cent at 5 and 10 years respectively. The principal site of recurrence was the peritoneum. Conclusion: Recurrence of PMP was rare after 5 years and exceptional after 10 years.

Model predicting the ypN0 status after good response to chemoradiotherapy in rectal cancer.

BACKGROUND: The purpose of this study was to identify the predictive factors for ypN0 status in tumors with good pathologic response to chemoradiotherapy (CRT). METHODS: A retrospective chart review was conducted on patients at two tertiary cancer center who underwent rectal resection after good response to CRT between 2000 and 2013. RESULTS: No preoperative treatment (oxaliplatin use, radiotherapy boost of 5,4 Gy, delay CRT-surgery) impacted on the ypN status. In the multivariate analysis, only a ypT<3 (HR 7.5 [2,9-19.5]) was significant and no lymphovascular invasion (HR 8,9 [1.6-49.8]) was limited to significance.The best model predicting the ypN0 status used only the ypT status<3. The major part (92.2%) of patients with ypT0-2 tumors had no LN invasion. CONCLUSION: The risk of lymph node involvement metastases was only 7.8% for the patients with an ypT0-2 status. A fullthickness transanal resection coud be the futur treatment of these patients.

Multicentre study of laparoscopic or open assessment of the peritoneal cancer index (BIG-RENAPE).

BACKGROUND: The peritoneal cancer index (PCI) is a comparative prognostic factor for colorectal peritoneal metastasis (CRPM). The ability of laparoscopy to determine the PCI in consideration of cytoreductive surgery remains undetermined, and this study was designed to compare it with laparotomy. METHODS: A prospective multicentre study was conducted for patients with no known CRPM, but at risk of peritoneal disease. Surgery began with laparoscopic exploration followed by open exploration to determine the PCI. Concordance between laparoscopic and open assessment was evaluated for the diagnosis of CRPM and for the PCI. RESULTS: Among 50 patients evaluated, CRPM recurrence was found in 29 (58 per cent) and 34 (68 per cent) at laparoscopic and open surgery respectively. Laparoscopy was feasible in 88 per cent (44 of 50) and deemed satisfactory by the surgeon in 52 per cent (26 of 50). Among the 25 evaluable patients with satisfactory laparoscopy, there was concordance of 96 per cent (24 of 25 patients) and 38 per cent (10 of 25) for laparoscopic and open assessment of CRPM and the PCI respectively. Where there were discrepancies, it was laparoscopy that underestimated the PCI. CONCLUSION: Laparoscopy may underestimate the extent of CRPM.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei of appendicular and extra-appendicular origin.

BACKGROUND: The prognostic value of the primary neoplasm responsible for pseudomyxoma peritonei (PMP) remains poorly studied. The aim of this study was to determine the prognosis for patients with extra-appendicular PMP (EA-PMP) treated optimally with complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: All patients treated for PMP with CCRS and HIPEC between 1994 and 2016 were selected retrospectively from a French multicentre database. Patients with EA-PMP had pathologically confirmed non-neoplastic appendices and were matched in a 1 : 4 ratio with patients treated for appendicular PMP (A-PMP), based on a propensity score. RESULTS: Some 726 patients were identified, of which 61 (EA-PMP group) were matched with 244 patients (A-PMP group). The origins of primary tumours in the EA-PMP group included the ovary (45 patients), colon (4), urachus (4), small bowel (1), pancreas (1) and unknown (6). The median peritoneal carcinomatosis index was comparable in EA-PMP and A-PMP groups (15·5 versus 18 respectively; P = 0·315). In-hospital mortality (3 versus 2·9 per cent; P = 1·000) and major morbidity 26 versus 25·0 per cent; P = 0·869) were also similar between the two groups. Median follow-up was 66·9 months. The 5-year overall survival rate was 87·8 (95 per cent c.i. 83·2 to 92·5) per cent in the A-PMP group and 87 (77 to 96) per cent in the EA-PMP group. The 5-year disease-free survival rate was 66·0 (58·7 to 73·4) per cent and 70 (53 to 83) per cent respectively. CONCLUSION: Overall and disease-free survival following treatment with CCRS and HIPEC is similar in patients with pseudomyxoma peritonei of appendicular or extra-appendicular origin.

Organoids as preclinical models to improve intraperitoneal chemotherapy effectiveness for colorectal cancer patients with peritoneal metastases: Preclinical models to improve HIPEC.

BACKGROUND: Peritoneal metastases (PM), corresponding to tumor implants into the peritoneal cavity, are associated with impaired prognosis and low responsiveness to systemic chemotherapy. A new therapeutic approach has dramatically changed the prognosis of patients with PM from colorectal cancer (CRC), consisting in the association of a complete cytoreductive surgery followed by intraperitoneal chemotherapy associated to hyperthermia (HIPEC). Many drugs have been administered intraperitoneally, but no clear consensus has been approved. Therefore, relevant preclinical models are essentials for the efficient translation of treatments option into affected patients. METHOD: Organoids, the last generation of preclinical models, were used to rationalize and improve intraperitoneal chemotherapy. We tested several cytotoxics, combination, effect of hyperthermia, exposure duration and frequency. RESULTS: Organoids were a representative model of response to chemotherapies used for the treatment of PM from CRC; 460mg/m2 of oxaliplatin being the most efficient cytotoxic treatment. Repeated incubations with oxaliplatin; mimicking cycles of intraperitoneal treatment, resulted in an increased efficacy. CONCLUSION & DISCUSSION: Organoids are relevant models to study the chemosensitivity of peritoneal metastases from CRCs. These models could be used for large scale drug screening strategies or personalized medicine, for colorectal carcinoma but also for PM from other origins.

Long-term survival after aggressive treatment of relapsed serosal or distant pseudomyxoma peritonei.

INTRODUCTION: Complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have dramatically changed the prognosis of patients with pseudomyxoma peritonei (PMP). However, recurrences can still occur and no consensus has been reached regarding their optimal treatments. This study aimed to analyze the patterns of recurrence after CCRS plus HIPEC for PMP and potential subsequent treatments of these lesions. PATIENTS AND METHODS: Between 1992 and 2014, patients who had relapsed after treatment of PMP were selected from a prospective database of 251 patients who had undergone CCRS plus HIPEC with a curative intent. RESULTS: After a median follow-up of 85 months, 66 patients (26%) had relapsed with a median free interval of 25 months. The first recurrence was mostly located in the peritoneum, isolated in 50 patients (76%) and associated with extraperitoneal disease in 6 patients. Curatively intended treatment of the relapse, combining surgery and chemotherapy was achievable in 76% of the patients, leading to a 5-year overall survival (OS) rate of 83% from the date of treatment of the first recurrence. In contrast, the 5-year OS rate was only 27% (p < 0.001) for patients treated with non-curative therapy. An isolated peritoneal recurrence was predictive of greater amenability to curative therapy and a better prognosis. CONCLUSION: After CCRS plus HIPEC, serosal recurrences were more common than their distant counterparts. Distant relapses' emergence has raised the question of their optimal treatments. Very long-term survival can be obtained after further treatment of recurrent PMP for patients with limited disease and good general status.

Single-port endoscopic mesocolic and mesorectal excision using an extraperitoneal approach.

BACKGROUND: The extraperitoneal rectal dissection via a transanal approach facilitates the mesorectal dissection. The retroperitoneal approach for mesocolic excision may also offer some similar advantages. To complete the lymphadenectomy of extraperitoneal mesorectal resection, we developed an innovative approach for upper rectal and mesocolic excision via an exclusive retroperitoneal dissection using a single-port access at the site of the future stomy. METHODS: This study was a prospective pilot study and was conducted between 2013 and 2015 at two oncologic centers. Five consecutive patients, with ano-rectal cancer requiring permanent stoma, underwent this procedure. RESULTS: The bowel was never touched or mobilized to perform the lymphadenectomy, and no Trendelenburg was required. The median operative duration was 300 min (range 205-310). The quality of the surgical plane was classified as good (mesorectal) in the five patients. The median circumferential and distal margins were, respectively, 5 mm (range 1-20) and 20 mm (range 5-25). The median number of harvested lymph nodes was 11 (range 5-18). No laparotomy or multiport laparoscopy was required. There was no death. Two patients had perineal wound dehiscence (one minor and one major). CONCLUSIONS: The mesocolic excision via a retroperitoneal approach is feasible, completes naturally the transanal mesorectal excision and may confer several advantages including no morbidity of small bowel manipulation or Trendelenburg position. Further studies are required to analyze this approach.

Imaging of neuroendocrine tumors of the pancreas.

Pancreatic neuroendocrine tumors (PNETs) are rare and represent a heterogeneous disease. PNET can be functioning or non-functioning with different clinical presentations and different prognosis based on WHO and pTNM classifications. The role of imaging includes the localization of small functioning tumor, differentiation of these tumors from adenocarcinoma, identification of signs of malignancy and evaluation of extent. PNETs have a broad spectrum of appearance. On CT and MRI, most of functioning PNETs are well defined small tumors with intense and homogeneous enhancement on arterial and portal phases. However, some PNETs with a more fibrous content may have a more delayed enhancement that is best depicted on the delayed phase. Other PNETs can present as purely cystic, complex cystic and solid tumors and calcified tumors. Non-functioning PNETs are larger with less intense and more heterogeneous enhancement. Functional imaging is useful for disease staging, to detect disease recurrence or the primary but also to select patient candidate for peptide receptor radiometabolic treatment. Somatostatin receptor scintigraphy (SRS) (Octreoscan®) is still the most available technique. Gallium 68-SST analogue PET have been demonstrated to be more sensitive than SRS-SPEC and it will be the future of functional imaging for NET. Finally, 18FDG PET/CT is indicated for more aggressive PNET as defined either by negative SRS and huge tumor burden or ki67 above 10% or poorly differentiated PNEC tumors.

Diffuse malignant peritoneal mesothelioma: Evaluation of systemic chemotherapy with comprehensive treatment through the RENAPE Database: Multi-Institutional Retrospective Study.

PURPOSE: Diffuse malignant peritoneal mesothelioma (DMPM) is a severe disease with mainly locoregional evolution. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is the reported treatment with the longest survival. The aim of this study was to evaluate the impact of perioperative systemic chemotherapy strategies on survival and postoperative outcomes in patients with DMPM treated with curative intent with CRS-HIPEC, using a multi-institutional database: the French RENAPE network. PATIENTS AND METHODS: From 1991 to 2014, 126 DMPM patients underwent CRS-HIPEC at 20 tertiary centres. The population was divided into four groups according to perioperative treatment: only neoadjuvant chemotherapy (NA), only adjuvant chemotherapy (ADJ), perioperative chemotherapy (PO) and no chemotherapy before or after CRS-HIPEC (NoC). RESULTS: All groups (NA: n = 42; ADJ: n = 16; PO: n = 16; NoC: n = 48) were comparable regarding clinicopathological data and main DMPM prognostic factors. After a median follow-up of 61 months, the 5-year overall survival (OS) was 40%, 67%, 62% and 56% in NA, ADJ, PO and NoC groups, respectively (P = 0.049). Major complications occurred for 41%, 45%, 35% and 41% of patients from NA, ADJ, PO and NoC groups, respectively (P = 0.299). In multivariate analysis, NA was independently associated with worse OS (hazard ratio, 2.30; 95% confidence interval, 1.07-4.94; P = 0.033). CONCLUSION: This retrospective study suggests that adjuvant chemotherapy may delay recurrence and improve survival and that NA may impact negatively the survival for patients with DMPM who underwent CRS-HIPEC with curative intent. Upfront CRS and HIPEC should be considered when achievable, waiting for stronger level of scientific evidence.