Perioperative FLOT: new standard for gastric cancer?

Machine-learning model derived gene signature predictive of paclitaxel survival benefit in gastric cancer: results from the randomised phase III SAMIT trial

OBJECTIVE

To date, there are no predictive biomarkers to guide selection of patients with gastric cancer (GC) who benefit from paclitaxel. Stomach cancer Adjuvant Multi-Institutional group Trial (SAMIT) was a 2×2 factorial randomised phase III study in which patients with GC were randomised to Pac-S-1 (paclitaxel +S-1), Pac-UFT (paclitaxel +UFT), S-1 alone or UFT alone after curative surgery.

DESIGN

The primary objective of this study was to identify a gene signature that predicts survival benefit from paclitaxel chemotherapy in GC patients. SAMIT GC samples were profiled using a customised 476 gene NanoString panel. A random forest machine-learning model was applied on the NanoString profiles to develop a gene signature. An independent cohort of metastatic patients with GC treated with paclitaxel and ramucirumab (Pac-Ram) served as an external validation cohort.

RESULTS

From the SAMIT trial 499 samples were analysed in this study. From the Pac-S-1 training cohort, the random forest model generated a 19-gene signature assigning patients to two groups: Pac-Sensitive and Pac-Resistant. In the Pac-UFT validation cohort, Pac-Sensitive patients exhibited a significant improvement in disease free survival (DFS): 3-year DFS 66% vs 40% (HR 0.44, p=0.0029). There was no survival difference between Pac-Sensitive and Pac-Resistant in the UFT or S-1 alone arms, test of interaction p<0.001. In the external Pac-Ram validation cohort, the signature predicted benefit for Pac-Sensitive (median PFS 147 days vs 112 days, HR 0.48, p=0.022).

CONCLUSION

Using machine-learning techniques on one of the largest GC trials (SAMIT), we identify a gene signature representing the first predictive biomarker for paclitaxel benefit.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry: C000000082 (SAMIT); ClinicalTrials.gov identifier, 02628951 (South Korean trial).

Effect of peri-operative chemotherapy regimen on survival in the treatment of locally advanced oesophago-gastric adenocarcinoma - A comparison of the FLOT and 'MAGIC' regimens

BACKGROUND

Peri-operative chemotherapy improves survival in patients with locally advanced oesophago-gastric adenocarcinoma. Two regimens with proven survival benefits are epirubicin, cisplatin plus capecitabine or fluorouracil (Medical Research Council Adjuvant Gastric Infusional Chemotherapy, MAGIC) and fluorouracil plus leucovorin, oxaliplatin, and docetaxel (FLOT). This study aimed to compare the effect of these regimens on survival (primary aim) and pathological response, surgical complications, adverse events and chemotherapy completion rates.

METHODS

Cohort study including 946 patients treated with FLOT (n = 257) or MAGIC (n = 689) who underwent surgical resection for oesophageal (n = 743) or gastric (n = 203) adenocarcinoma between 2002 and 2021 at St Thomas' Hospital or The Royal Marsden Hospital, London, UK. Survival analysis was performed using multivariable Cox regression, providing hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for age, sex, clinical T-stage, clinical N-stage, tumour grade and presence of signet ring cells.

RESULTS

Patients treated with FLOT had better overall survival (HR = 0.69, 95% CI 0.50-0.94) and disease-free survival (HR = 0.75, 95% CI 0.58-0.98) than MAGIC. Patients treated with FLOT were more likely to have a complete pathological response (9.5% FLOT versus 5.5% MAGIC, p = 0.027) and were less likely to have a positive resection margin (19.1% FLOT versus 32.2% MAGIC, p < 0.001). The stratified analysis revealed similar results for oesophageal and gastric tumours. Rates of surgical complications, chemotherapy-associated adverse events and completion were similarly distributed between treatment groups.

CONCLUSIONS

Patients with oesophageal or gastric adenocarcinoma treated with peri-operative FLOT had better survival and pathological response than those treated with peri-operative MAGIC. Rates of surgical complications, adverse events and chemotherapy completion were comparable.

CircPTK2 Suppresses the Progression of Gastric Cancer by Targeting the MiR-196a-3p/AATK Axis

Background

Gastric cancer is a type of malignant tumor with high morbidity and mortality. It has been shown that circular RNAs (circRNAs) exert critical roles in gastric cancer progression via working as microRNA (miRNA) sponges to regulate gene expression. However, the role and potential molecular mechanism of circRNAs in gastric cancer remain largely unknown.

Methods

CircPTK2 (hsa_circ_0005273) was identified by bioinformatics analysis and validated by RT-qPCR assay. Bioinformatics prediction, dual-luciferase reporter, and RNA pull-down assays were used to determine the interaction between circPTK2, miR-196a-3p, and apoptosis-associated tyrosine kinase 1 (AATK).

Results

The level of circPTK2 was markedly downregulated in gastric cancer tissues and gastric cancer cells. Upregulation of circPTK2 significantly suppressed the proliferation, migration, and invasion of gastric cancer cells, while circPTK2 knockdown exhibited opposite effects. Mechanically, circPTK2 could competitively bind to miR-196a-3p and prevent miR-196a-3p to reduce the expression of AATK. In addition, overexpression of circPTK2 inhibited tumorigenesis in a xenograft mouse model of gastric cancer.

Conclusion

Collectively, circPTK2 functions as a tumor suppressor to suppress gastric cancer cell proliferation, migration, and invasion through regulating the miR-196a-3p/AATK axis, suggesting that circPTK2 may serve as a novel therapeutic target for gastric cancer.

Perioperative or postoperative adjuvant oxaliplatin with S-1 versus adjuvant oxaliplatin with capecitabine in patients with locally advanced gastric or gastro-oesophageal junction adenocarcinoma undergoing D2 gastrectomy (RESOLVE): an open-label, superiority and non-inferiority, phase 3 randomised controlled trial

BACKGROUND

The optimal perioperative chemotherapeutic regimen for locally advanced gastric cancer remains undefined. We evaluated the efficacy and safety of perioperative and postoperative S-1 and oxaliplatin (SOX) compared with postoperative capecitabine and oxaliplatin (CapOx) in patients with locally advanced gastric cancer undergoing D2 gastrectomy.

METHODS

We did this open-label, phase 3, superiority and non-inferiority, randomised trial at 27 hospitals in China. We recruited antitumour treatment-naive patients aged 18 years or older with historically confirmed cT4a N+ M0 or cT4b Nany M0 gastric or gastro-oesophageal junction adenocarcinoma, with Karnofsky performance score of 70 or more. Patients undergoing D2 gastrectomy were randomly assigned (1:1:1) via an interactive web response system, stratified by participating centres and Lauren classification, to receive adjuvant CapOx (eight postoperative cycles of intravenous oxaliplatin 130 mg/m² on day one of each 21 day cycle plus oral capecitabine 1000 mg/m² twice a day), adjuvant SOX (eight postoperative cycles of intravenous oxaliplatin 130 mg/m² on day one of each 21 day cycle plus oral S-1 40-60 mg twice a day), or perioperative SOX (intravenous oxaliplatin 130 mg/m² on day one of each 21 day plus oral S-1 40-60 mg twice a day for three cycles preoperatively and five cycles postoperatively followed by three cycles of S-1 monotherapy). The primary endpoint, assessed in the modified intention-to-treat population, 3-year disease-free survival to assess the superiority of perioperative-SOX compared with adjuvant-SOX and the non-inferiority (hazard ratio non-inferiority margin of 1·33) of adjuvant-SOX compared with adjuvant-CapOx. Safety analysis were done in patients who received at least one dose of the assigned treatment. This study is registered with ClinicalTrials.gov, NCT01534546.

FINDINGS

Between Aug 15, 2012, and Feb 28, 2017, 1094 patients were screened and 1022 (93%) were included in the modified intention-to-treat population, of whom 345 (34%) patients were assigned to the adjuvant-CapOx, 340 (33%) patients to the adjuvant-SOX group, and 337 (33%) patients to the perioperative-SOX group. 3-year disease-free survival was 51·1% (95% CI 45·5-56·3) in the adjuvant-CapOx group, 56·5% (51·0-61·7) in the adjuvant-SOX group, and 59·4% (53·8-64·6) in the perioperative-SOX group. The hazard ratio (HR) was 0·77 (95% CI 0·61-0·97; Wald p=0·028) for the perioperative-SOX group compared with the adjuvant-CapOx group and 0·86 (0·68-1·07; Wald p=0·17) for the adjuvant-SOX group compared with the adjuvant-CapOx group. The most common grade 3-4 adverse events was neutropenia (32 [12%] of 258 patients in the adjuvant-CapOx group, 21 [8%] of 249 patients in the adjuvant-SOX group, and 30 [10%] of 310 patients in the perioperative-SOX group). Serious adverse events were reported in seven (3%) of 258 patients in adjuvant-CapOx group, two of which were related to treatment; eight (3%) of 249 patients in adjuvant-SOX group, two of which were related to treatment; and seven (2%) of 310 patients in perioperative-SOX group, four of which were related to treatment. No treatment-related deaths were reported.

INTERPRETATION

Perioperative-SOX showed a clinically meaningful improvement compared with adjuvant-CapOx in patients with locally advanced gastric cancer who had D2 gastrectomy; adjuvant-SOX was non-inferior to adjuvant-CapOx in these patients. Perioperative-SOX could be considered a new treatment option for patients with locally advanced gastric cancer.

FUNDING

National Key Research and Development Program of China, Beijing Scholars Program 2018-2024, Peking University Clinical Scientist Program, Taiho, Sanofi-Aventis, and Hengrui Pharmaceutical.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Perioperative Safety and Effectiveness of Neoadjuvant Therapy with Fluorouracil, Leucovorin, Oxaliplatin, and Docetaxel Plus Apatinib in Locally Advanced Gastric Cancer

Purpose

The trend in neoadjuvant therapy for locally advanced gastric cancer (LAGC) is to use more drugs or therapies in combination. This study aimed to assess the safety and effectiveness of neoadjuvant chemotherapy with fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) plus apatinib in the treatment of LAGC.

Patients and Methods

We collected clinical data from patients with LAGC who received neoadjuvant FLOT and apatinib therapy and underwent surgery from January 2017 to December 2020. Patients were divided into either the FLOT group (in which patients received FLOT neoadjuvant therapy and surgery) or the FLOTA group (in which patients received FLOT plus apatinib neoadjuvant therapy and surgery).

Results

The FLOT and FLOTA groups contained 44 and 31 patients, respectively. There were significant differences between the FLOT and FLOTA groups in the objective response rate (50.00% vs. 80.65%, respectively, p = 0.008) and average change from baseline in the target lesion size (−26.16 ± 34.61 vs. −54.32 ± 36.11, respectively, p < 0.001). There were also significant differences in the pretreatment clinical tumor-node-metastasis (cTNM) and post treatment cTNM stages for the FLOT group (p = 0.001) and for the FLOTA group (p < 0.001). There were no significant differences between the FLOT and FLOTA groups in post neoadjuvant therapy cTNM stages (p = 0.525), R0 rate (p = 0.397), tumor regression grade (p = 0.397), or post treatment pathological TNM stage (p = 0.180). Some neoadjuvant therapy-related adverse events occurred significantly more frequently in the FLOTA group, including diarrhea (all grades), pain (all grades), oral mucositis (all grades), and hand-foot syndrome (all grades).

Conclusion

The FLOTA regimen can achieve better perioperative efficacy and acceptable toxicity compared with that of the FLOT regimen in neoadjuvant treatment of LAGC. The FLOTA regimen for neoadjuvant therapy for LAGC merits further study.

Trial watch: IDO inhibitors in cancer therapy

Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first, rate-limiting step of the so-called “kynurenine pathway”, which converts the essential amino acid L-tryptophan (Trp) into the immunosuppressive metabolite L-kynurenine (Kyn). While expressed constitutively by some tissues, IDO1 can also be induced in specific subsets of antigen-presenting cells that ultimately favor the establishment of immune tolerance to tumor antigens. At least in part, the immunomodulatory functions of IDO1 can be explained by depletion of Trp and accumulation of Kyn and its derivatives. In animal tumor models, genetic or pharmacological IDO1 inhibition can cause the (re)activation of anticancer immune responses. Similarly, neoplasms expressing high levels of IDO1 may elude anticancer immunosurveillance. Therefore, IDO1 inhibitors represent promising therapeutic candidates for cancer therapy, and some of them have already entered clinical evaluation. Here, we summarize preclinical and clinical studies testing IDO1-targeting interventions for oncologic indications.

FLOT Neoadjuvant Chemotherapy Followed by Laparoscopic D2 Gastrectomy in the Treatment of Locally Resectable Advanced Gastric Cancer

BACKGROUND

The prognosis of patients with advanced gastric cancer remains unsatisfactory, highlighting the need for improved therapeutic strategies. We analyzed 23 resectable advanced gastric cancer patients who received FLOT followed by laparoscopic gastrectomy with D2 lymphadenectomy to evaluate the efficacy and safety.

METHODS

Patients aged 18-75 years with gastric adenocarcinoma (stage cT3-4 and/or N + M0) underwent neoadjuvant FLOT therapy (four preoperative and four postoperative 2-week cycles) at Shanghai East Hospital. Laparoscopic gastrectomy was scheduled 3-4 weeks after completion of the last cycle of preoperative chemotherapy. The type of surgical procedure was determined by the location and extent of the primary tumor.

RESULTS

23 patients were reviewed in the study. 20 patients (81.2%) received four courses of FOLT therapy, while 3 patients (18.8%) received three courses of treatment. There were 3 (13.0%) complete responses, 13 (56.5%) partial responses, 4 (26.1%) of stable disease, and 1 (4.3%) of progressive disease. The clinical efficacy response rate was 69.6%. The R0 resection rate was 91.3%. Only one patient exhibited grade III postoperative complications. The pathologic complete remission was 13%. The common grade 3/4 adverse events from chemotherapy were leucopenia (17.4%), neutropenia (30.4%), anemia (13%), anorexia (13%), and nausea (17.4%). Postoperative complications occurred in 5 patients (26.1%). There was no treatment-related mortality or reoperation. The most reason for not completing chemotherapy was the patient's request.

CONCLUSIONS

These findings suggest that FLOT neoadjuvant chemotherapy, followed by laparoscopic D2 gastrectomy, is effective and safe in advanced, resectable advanced gastric cancer.

Stage IV Gastric Cancer: The Surgical Perspective of the Italian Research Group on Gastric Cancer

Background/Aim: This work explored the prognostic role of curative versus non-curative surgery, the prognostic value of the various localizations of metastatic disease, and the possibility of identifying patients to be submitted to aggressive therapies. Patients and Methods: Retrospective chart review of stage IV patients operated on in our institutions. Results: Two hundred and eighty-two patients were considered; 73.4% had a single metastatic presentation. In 117 cases, a curative (R0) resection of primary and metastases was possible; 75 received a R1 resection and 90 a palliative R2 gastrectomy. Surgery was integrated with chemotherapy in multiple forms: conversion therapy, HIPEC, neo-adjuvant and adjuvant treatment. Median overall survival (OS) of the entire cohort was 10.9 months, with 14 months for the R0 subgroup. There was no correlation between metastasis site and survival. At multivariate analysis, several variables associated with the lymphatic sphere showed prognostic value, as well as tumor histology and the curativity of the surgical procedure, with a worse prognosis associated with a low number of resected nodes, D1 lymphectomy, pN3, non-intestinal histology, and R+ surgery. Considering the subgroup of R0 patients, the variables pT, pN and D displayed an independent prognostic role with a cumulative effect, showing that patients with no more than 1 risk factor can reach a median survival of 33 months. Conclusions: Our data show that the possibility of effective care also exists for Western patients with stage IV gastric cancer.

Preclinical evaluation of exemestane as a novel chemotherapy for gastric cancer

CYP19A1/aromatase (Ar) is a prognostic biomarker of gastric cancer (GCa). Ar is a critical enzyme for converting androstenedione to oestradiol in the steroidogenesis cascade. For decades, Ar has been targeted with Ar inhibitors (ARIs) in gynaecologic malignancies; however, it is unexplored in GCa. A single‐cohort tissue microarray examination was conducted to study the association between Ar expression and disease outcome in Asian patients with GCa. The results revealed that Ar was a prognostic promoter. Bioinformatics analyses conducted on a Caucasian‐based cDNA microarray databank showed Ar to be positively associated with GCa prognosis for multiple clinical modalities, including surgery, 5‐Fluorouracil (5‐FU) for adjuvant chemotherapy, or HER2 positivity. These findings imply that targeting Ar expression exhibits a potential for fulfilling unmet medical needs. Hence, Ar‐targeting compounds were tested, and the results showed that exemestane exhibited superior cancer‐suppressing efficacy to other ARIs. In addition, exemestane down‐regulated Ar expression. Ablating Ar abundance with short hairpin (sh)Ar could also suppress GCa cell growth, and adding 5‐FU could facilitate this effect. Notably, adding oestradiol could not prevent exemestane or shAr effects, implicating a nonenzymatic mechanism of Ar in cancer growth. Regarding translational research, treatment with exemestane alone exhibited tumour suppression efficacy in a dose‐dependent manner. Combining subminimal doses of 5‐FU and exemestane exerted an excellent tumour suppression effect without influencing bodyweight. This study validated the therapeutic potentials of exemestane in GCa. Combination of metronomic 5‐FU and exemestane for GCa therapy is recommended.