Preventive HIPEC in combination with perioperative FLOT versus FLOT alone for resectable diffuse type gastric and gastroesophageal junction type II/III adenocarcinoma – the phase III “PREVENT”- (FLOT9) trial of the AIO /CAOGI /ACO

Background The main reason for treatment failure after curative surgical resection of gastric cancer is intra-abdominal spread, with 40–50% peritoneal seeding as primary localization of recurrence. Peritoneal relapse is seen in 60–70% of tumors of diffuse type, compared to only 20–30% of intestinal type. Hyperthermic IntraPEritoneal Chemoperfusion (HIPEC) is an increasingly used therapy method for patients with peritoneal metastases. The preventive use of HIPEC could represent an elegant approach for patients (pts) before macroscopic peritoneal seeding, since pts. with operable disease are fit and may have potential risk of microscopic involvement, thus having a theoretical chance of cure with HIPEC even without the need for cytoreduction. No results from a PCRT from the Western hemisphere have yet been published. Methods This is a multicenter, randomized, controlled, open-label study including a total of 200 pts. with localized and locally advanced diffuse or mixed type (Laurens’s classification) adenocarcinoma of the stomach and Type II/III GEJ. All enrolled pts. will have received 3–6 pre-operative cycles of biweekly FLOT (Docetaxel 50 mg/m2; Oxaliplatin 85 mg/m2; Leucovorin 200 mg/m2; 5-FU 2600 mg/m2, q2wk). Pts will be randomized 1:1 to receive surgery only and postoperative FLOT (control arm) or surgery + intraoperative HIPEC (cisplatin 75 mg/m2 solution administered at a temperature of 42 °C for 90 min) and postoperative FLOT (experimental arm). Surgery is carried out as gastrectomy or transhiatal extended gastrectomy. Primary endpoint is PFS/DFS, major secondary endpoints are OS, rate of pts. with peritoneal relapse at 2 and 3 years, perioperative morbidity/mortality and quality of life. The trial starts with a safety run-in phase. After 20 pts. had curatively intended resection in Arm B, an interim safety analysis is performed. Recruitment has already started and first patient in was on January 18th, 2021. Discussion If the PREVENT concept proves to be effective, this could potentially lead to a new standard of therapy. On the contrary, if the outcome is negative, pts. with gastric cancer and no peritoneal involvement will not be treated with HIPEC during surgery. Trial registration The study is registered on June 25th, 2020 under ClinicalTrials.gov Identifier: NCT04447352; EudraCT: 2017-003832-35.

Splenosis Mimicking Peritoneal Seeding of Advanced Colon Cancer Can Be Identified by Spleen SPECT/CT and FDG PET/CT

This case report demonstrates that Tc-99m labeled heat-damaged red blood cell single-photon emission computed tomography/computed tomography (spleen SPECT/CT) and F-18 fluorodeoxyglucose positron emission tomography/CT (FDG PET/CT) could noninvasively confirm splenosis mimicking peritoneal seeding of advanced sigmoid colon cancer with hepatic metastases, and played a crucial role in determining the treatment plan.

Preventive HIPEC in combination with perioperative FLOT versus FLOT alone for resectable diffuse type gastric and gastroesophageal junction type II/III adenocarcinoma: The phase III “PREVENT” trial of the AIO /CAOGI /ACO.

TPS4149 Background: The main reason for treatment failure after curative surgical resection of gastric cancer is intra-abdominal spread, with 40- 50% peritoneal seeding as primary localization of recurrence. Peritoneal relapse is seen in 60-70% of tumors of diffuse type, compared to only 20-30% of intestinal type. Hyperthermic IntraPEritoneal Chemoperfusion (HIPEC) is an increasingly used therapy method for patients with peritoneal metastases. The preventive use of HIPEC could represent an elegant approach for patients (pts) before macroscopic peritoneal seeding, since patients with operable disease are fit and may have potential risk of microscopic involvement, thus having a theoretical chance of cure with HIPEC even without the need for cytoreduction. No results from a PCRT from the Western hemisphere have yet been published. Methods: This is a multicenter, randomized, controlled, open-label study including a total of 200 pts with localized and locally advanced diffuse and mixed type (Laurens`s classification) adenocarcinoma of the stomach and Type II/III GEJ (i.e. ≥cT3 any N or any T N positive). All enrolled pts will have received 3-6 pre-operative cycles of biweekly FLOT (Docetaxel 50 mg/m²; Oxaliplatin 85 mg/m²; Leucovorin 200 mg/m²; 5-FU 2600 mg/m², q2wk). Pts will be randomized 1:1 to receive surgery only and postoperative FLOT (Arm A- Control arm) or surgery + intraoperative HIPEC (cisplatin 75mg/m2 solution administered at a temperature of 42°C for 90 minutes) and postoperative FLOT (Arm B- experimental arm). Surgery is carried out as gastrectomy or transhiatal extended gastrectomy. Primary endpoint is PFS/DFS, major secondary endpoints are OS, R0 resection rate, perioperative morbidity/mortality including VAS pain score and quality of life as assessed by EORTC QLQ C30 questionnaire. The trial starts with a safety run-in phase. After 20 patients had curatively intended resection in Arm B, an interim safety analysis is performed assessing feasibility, safety, and tolerability in Arm B. First patient was randomized on 18JAN2021. Currently one patient is recruited. EudraCT: 2017-003832-35; ClinicalTrials.gov ID: NCT04447352. Clinical trial information: NCT04447352.

Prognostic value of regional lymph node involvement in patients with metastatic colorectal cancer: palliative versus curative resection

Background Approximately 20% of patients with colorectal cancer are initially diagnosed with stage IV disease. This study aims to examine the role of regional lymph node (LN) status in metastatic colorectal cancer (mCRC) with respect to clinicopathologic features and survival outcomes. Methods We investigated 1147 patients diagnosed with mCRC and had undergone surgical resection of the primary CRC. A total of 167 patients were placed in the LN-negative (LN−) group and another 980 in the LN-positive (LN+) group. Results LN+ patients exhibited a significantly higher rate of T4 tumors (p = 0.008), poorly differentiated adenocarcinoma (p < 0.001), lymphovascular invasion (p < 0.001), and perineural invasion (p < 0.001) than those in the LN− group. LN− patients had a significantly higher rate of lung metastasis (p < 0.001), whereas the rate of peritoneal seeding (p < 0.001) and systemic node metastasis (p < 0.001) was both significantly higher in the LN+ group. The 5-year overall survival (OS) in the LN+ group was significantly poorer than that in the LN− group (LN− vs. LN+ 23.2% vs. 18.1%; p = 0.040). In patients with curative resection, the 5-year OS rate has no significant difference between the two groups (LN− vs. LN+ 19.5% vs. 24.3%; p = 0.890). Conclusions Metastatic CRC patients with LN+ who underwent primary tumor resection may present with more high-risk pathological features, more peritoneal seeding, and systemic node metastasis, but less lung metastasis than LN− patients. LN+ patients had poorer long-term outcomes compared with that in LN− patients. Nevertheless, with curative resection, LN+ patients could have similar survival outcomes as LN− patients.

Is Increased Peritoneal Seeding a Drawback After Using Intracorporeal Anastomosis in Laparoscopic Right Colectomy? A Propensity Score-Matched Study

Backgrounds: Though better short-term outcomes were frequently reported, differences in specimen parameters and the rate of subsequent peritoneal seeding between intracorporeal anastomosis (IA) and extracorporeal anastomoses (EA) for laparoscopic right hemicolectomy have not been analyzed. We aimed to compare the pathologic differences and oncological outcomes between these two approaches.Methods: We retrospectively analyzed 217 consecutive patients who underwent laparoscopic right hemicolectomies from September 2016 to April 2018, and classified them into IA and EA groups, based on the approach used. Propensity score matching analysis was performed, after which 101 patients were included in each group.Results: The IA group had a longer operative time, shorter length of stay, shorter time to first flatus and tolerating a soft diet, and better pain scale scores at postoperative day 3. No inter-group differences in conversion, postoperative complication, mortality, or readmission rates were found. The IA group had a longer resected colon length (23.67 vs. 19.75 cm, p=0.010) and nearest resected margin (7.51 vs. 5.40 cm, p=0.010) for cancer near the hepatic flexure. There are comparable 3-year overall survival (87.7% vs. 89.6%, p=0.604) and disease free survival (75.0% vs. 75.7%, p=0.842) between IA and EA groups. The occurrence of peritoneal seeding was similar between the groups too.Conclusions: IA ensures better recovery and comparable complications to EA. The former also achieved a more precise tumor excision. It is a valid technique without compromising oncological outcomes.

Dietary fats suppress the peritoneal seeding of colorectal cancer cells through the TLR4/Cxcl10 axis in adipose tissue macrophages

Peritoneal carcinomatosis (PC) of colorectal cancer (CRC) is a terminal phase of malignancy with no effective strategies for the prevention of this condition. Here we established PC models in mice by intraperitoneal engraftment of CRC cells and revealed an unexpected role for a high-fat diet (HFD) in preventing metastatic seeding in the visceral fat. Mechanistically, the HFD stimulated the activation of adipose tissue macrophages (ATMs) toward an M1-like phenotype and enhanced ATM tumor phagocytosis in a TLR4-dependent manner. Furthermore, the TLR4–Cxcl10 axis in ATMs promoted T cell recruitment, and M1-like macrophages stimulated T cell activation in tumor-seeded fats. The inhibitory effect of the HFD on tumor seeding was abolished with the ablation of macrophages, inactivation of T cells, or blockade of the TLR4–Cxcl10 axis in macrophages. Finally, we showed that a HFD and conventional chemotherapeutic agents (oxaliplatin or 5-fluorouracil) synergistically improved the survival of tumor-seeded mice. Collectively, our findings demonstrate that peritoneal seeding of CRC can be suppressed by short-term treatment with a HFD in the early phase, providing a novel concept for the management of these patients in the clinic.