ypTNM staging after neoadjuvant chemotherapy in the Chinese gastric cancer population: an evaluation on the prognostic value of the AJCC eighth edition cancer staging system

Abstract

Background This study aims to evaluate the new ypTNM staging system in Chinese gastric cancer patients. Methods We conducted retrospective survival and regression analyses using a database of gastric cancer patients who underwent neoadjuvant chemotherapy at the Peking University Cancer Hospital and Institute from January 2007 to January 2015. Results A total of 473 patients were included in the study with 28 pathological complete response (pCR) cases, 3 ypT0N1 cases, 65 stage I cases, 126 stage II cases, and 251 stage III cases. The pCR cases had similar survival to stage I patients (p > 0.05). The 3-year disease-free survival (DFS) and 5-year overall survival (OS) rates of stage I, II and III patients were significantly different (3-year DFS: 89.0, 75.5, and 39.6%, p < 0.001; 5-year OS: 89.6, 65.5, and 36.5%, p = 0.001). Both ypT and ypN are independent predictors of patient survival, while further log-rank tests showed that the ypN stage is of better prognostic value than ypT. Subgrouping analysis revealed that stage III patients of ypT4b and ypN3 had worse survival compared to the rest of stage III cases (p < 0.001). The c-index values of the ypTNM stage and modified ypTNM stage (stage III divided into IIIa and IIIb) were 0.657 and 0.708, respectively (p < 0.001). Conclusions Our data showed significant differences in survival among gastric cancer patients at different ypTNM stages, indicating its prognostic value in the Chinese population. Further detailed analyses may facilitate the subgrouping of each stage to allow for a more accurate evaluation of disease prognosis in gastric cancer patients.

<p>A Modified ypTNM Staging System–Development and External Validation of a Nomogram Predicting the Overall Survival of Gastric Cancer Patients Received Neoadjuvant Chemotherapy</p>

“…In our previous study, it was shown that the discriminative ability of this system was not high enough to meet clinical demand. 15 Moreover, the new ypTNM staging system did not address pCR and ypT0N1 patients. In this study, we developed a nomogram to predict the OS for targeting patients and conducted validation to prove its efficacy.…”

“…In our previous study, the discrimination of the TNM staging system was evaluated and the C-index was 0.657. 15…”

“…2 However, this system was developed from patients with less extensive lymph node dissection (less than D2) and thus may not be well applied to patients underwent D2 lymphadenectomy. In our previous study, we conducted a validation of this system (patients at T0 stage excluded) 15 and demonstrated that although ypTNM staging system was effective for staging, its predictive value was limited with a relatively low C-index (0.657). In addition, patients with a T0 stage were not included in ypTNM staging system and thus cannot be evaluated.…”

Downstaging depth score as a better surrogate endpoint than pCR, histological response and ypN0 for long-term outcomes in locally advanced gastric cancer patients after preoperative chemo-radiotherapy

“…The clinicopathological factors that predict prognosis have been discussed in several studies, and histological response and ypTNM stage after neoadjuvant therapy are generally considered effective predictors (15)(16)(17)(18)(19)(20)(21)(22)(23)..Yukinori compared the prognostic value of evaluation criteria, the Response Evaluation Criteria in Solid Tumors (RECIST) standard, the Japanese Classification of Gastric Cancer (JCGC) standard and the histological response. A total of 100 patients were included in the JCOG0210 and JCOG0405 studies.…”

Clinical Value of Energy Spectrum Curves of Dual-energy CT in Evaluating Pathological Grading of Gastric Adenocarcinoma

“…Computer tomography(CT) staging and endoscopic ultrasonography (EUS) staging of gastric cancer were independently classified by the Alliance Against Cancer and the 8th edition American joint committee on cancer (AJCC) TNM staging system [5,6,7]. In clinical practice, CT examination has become the main means of T staging of gastric cancer before treatment because of its simplicity, rapidity and objective image advantages [8].…”