Study protocol of a multicenter phase III randomized controlled trial investigating the efficiency of the combination of neoadjuvant chemotherapy (NAC) and neoadjuvant laparoscopic intraperitoneal hyperthermic chemotherapy (NLHIPEC) followed by R0 gastrectomy with intraoperative HIPEC for advanced gastric cancer (AGC): dragon II trial

Abstract

Background: Even though treatment modalities such as adjuvant systemic radio-chemotherapy and neoadjuvant chemotherapy (NAC) have individually have improved overall survival (OS) and progression-free survival (PFS) rates in advanced Gastric Cancer (AGC), the peritoneum still presides as a common site of treatment failure and disease recurrence. The role of hyperthermic intraperitoneal chemotherapy (HIPEC) has been acknowledged as prophylaxis for peritoneal carcinomatosis (PC) in AGC patients and in this study, we aim at investigating the safety and efficacy of the combination of neoadjuvant laparoscopic HIPEC (NLHIPEC) with NAC in the neoadjuvant phase followed by surgery of curative intent with intraoperative HIPEC followed by adjuvant chemotherapy (AC).

Methods: In this multicenter Phase III randomized controlled trial, 326 patients will be randomly separated into 2 groups into a 1:1 ratio after laparoscopic exploration. The experiment arm will receive the proposed comprehensive Dragon II regimen while the control group will undergo standard R0 D2 followed by 8 cycles of AC with oxaliplatin with S-1 (SOX) regimen. The Dragon II regimen comprises of 1 cycle of NLHIPEC for 60mins at 43 ± 0.5 °C with 80 mg/m² of Paclitaxel followed by 3 cycles of NAC with SOX regimen and after assessment, standard R0 D2 gastrectomy with intraoperative HIPEC followed by 5 cycles of SOX regimen chemotherapy. The end-points for the study are 5 year PFS, 5 year OS, peritoneal metastasis rate (PMR) and morbidity rate.

Discussion: This study is one of the first to combine NLHIPEC with NAC in the preoperative phase which is speculated to provide local management of occult peritoneal carcinomatosis or peritoneal free cancer cells while NAC will promote tumor downsizing and down-staging. The addition of the intraoperative HIPEC is speculated to manage dissemination due to surgical trauma. Where the roles of intraoperative HIPEC and NAC have individually been investigated, this study provides innovative insight on a more comprehensive approach to management of AGC at high risk of peritoneal recurrence. It is expected that the combination of NLHIPEC with NAC and HIPEC will increase PFS by 15% and decrease PMR after gastrectomy of curative intent.

Trial registration: World Health Organization Clinical Trials - International Registry Platform (WHO-ICTRP) with Registration ID ChiCTR1900024552, Registered Prospectively on the 16th July, 2019.

Keywords: Advanced gastric Cancer; Intraperitoneal Hyperthermic chemotherapy; Neoadjuvant chemotherapy; Peritoneal Carcinomatosis; Progression-free survival.

Fig. 1

Study Flow Chart

Fig. 2

Logrank Test Power Analysis Chart Section