ARTIST 2: Interim results of a phase III trial involving adjuvant chemotherapy and/or chemoradiotherapy after D2-gastrectomy in stage II/III gastric cancer (GC).

person Se Hoon Park Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea info_outline Se Hoon Park, Dae Young Zang, Boram Han, Jun Ho Ji, Tae Gyu Kim, Sung Yong Oh, In Gyu Hwang, Jung Hoon Kim, Dongbok Shin, Do Hoon Lim, Kyoung Mee Kim, Ji Yeong An, Min-Gew Choi, Jun-Ho Lee, Tae Sung Sohn, Jae-Moon Bae, Sung Kim, Seung Kim, Jeeyun Lee, Won Ki Kang

Authors person Se Hoon Park Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea info_outline Se Hoon Park, Dae Young Zang, Boram Han, Jun Ho Ji, Tae Gyu Kim, Sung Yong Oh, In Gyu Hwang, Jung Hoon Kim, Dongbok Shin, Do Hoon Lim, Kyoung Mee Kim, Ji Yeong An, Min-Gew Choi, Jun-Ho Lee, Tae Sung Sohn, Jae-Moon Bae, Sung Kim, Seung Kim, Jeeyun Lee, Won Ki Kang Organizations Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea, Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang, South Korea, Department of Internal Medicine, Hallym University Medical Center, Anyang, South Korea, Division of Hemato-Oncology, Department of Internal Medicine, Changwon Samsung Medical Center, Changwon, South Korea, Department of Radiation Oncology, Sungkyunkwan University Samsung Changwon Hospital, Changwon, South Korea, Department of Internal Medicine, Dong-A University College of Medicine, Busan, South Korea, Department of Internal Medicine, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, South Korea, Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, South Korea, Gachon University Gil Medical Center, Incheon, South Korea, Department of Radiation Oncology, Sungkyunkwan University Samsung Medical Center, Seoul, South Korea, Department of Pathology, Samsung Medical Center, Seoul, South Korea, Samsung Medical Center, Seoul, South Korea, Department of Surgery, Samsung Medical Center, Seoul, South Korea Abstract Disclosures Research Funding Other Background: Adjuvant chemotherapy and/or chemoradiotherapy have been the standard of care in GC for years, supported by randomized trials. We compared the efficacy of different chemotherapy regimens and chemoradiotherapy in patients with D2-resected, stage II/III, node-positive GC. Methods: From Feb 2013 through Nov 2018, we randomly assigned, in a 1:1:1 ratio, patients with pathologically-staged II or III, node-positive, D2-resected GC, to receive adjuvant S-1 (40-60 mg twice daily 4-weeks-on/2-weeks-off) for one year, S-1 (2-weeks-on/1-week-off) plus oxaliplatin 130 mg/m2 (SOX) for six months, or SOX plus chemoradiotherapy 45 Gy (SOXRT). Randomization was stratified according to the type of surgery (total or subtotal gastrectomy), stage (II or III), and Lauren histologic classification (diffuse or intestinal). The primary endpoint was disease-free survival (DFS). A total of 900 patients had to be enrolled to demonstrate superiority of SOX or SOXRT to S-1 (hazard ratio [HR] 0.667), with 90% power at a two-sided significance level of 5%. Results: A total of 538 patients were included for this interim efficacy analysis. Median age was 58 years, men constituted 65%, and stage II and III were 31% and 69%, respectively. Baseline tumor and patient characteristics were balanced between treatment arms. Adverse events were as anticipated in each arm, generally well-tolerated and manageable. DFS in the control arm (S-1) were significantly shorter than in SOX and SOXRT arms (stratified HR for recurrence): S-1 vs. SOX, 0.617 (P = 0.016) and S-1 vs. SOXRT, 0.686 (P = 0.057). The DFS at 3-years was found to be 65%, 78% and 73% in S-1, SOX and SOXRT arms, respectively. No difference in DFS between SOX and SOXRT was found (HR 0.910, P = 0.667). Based on the results after the observation of 145 recurrence events at the cutoff date of Dec 27, 2018, the independent data monitoring committee considered the results sufficient to meet the endpoint of the trial and recommended early stopping of the trial. Conclusions: In patients with curatively D2-resected, stage II/III, node-positive GC, adjuvant SOX or SOXRT was effective in prolonging DFS, when compared to S-1 monotherapy. Clinical trial information: NCT0176146.