Does postoperative chemotherapy improve overall survival of patients with ypT1-2N0 cancer?

BACKGROUND

Perioperative chemotherapy combined with curative gastrectomy has been increasingly represented the standard therapeutic strategy for resectable gastric cancer (GC). However, it is still unclear whether postoperative chemotherapy has a survival benefit for ypT1-2N0 gastric cancer patients who have undergone preoperative chemotherapy followed curative gastrectomy.

METHODS

The data of patients who undergone neoadjuvant chemotherapy followed by gastrectomy and had pathological classification of ypT1-2N0 between March 2016 and December 2020 at Peking Union Medical College Hospital were retrospectively reviewed. Chi-square test was adopted to compare the difference between the patients with postoperative chemotherapy (pCHT) and without postoperative chemotherapy (no pCHT). Survival curves for overall survival (OS) were estimated using the Kaplan-Meier method, and the log-rank test was used to compare survival difference. Univariate and multivariate analyses for prognostic factors were based on the Cox regression.

RESULTS

A total of 134 patients met the inclusion criteria and 56 (41.8%) of them have undergone postoperative chemotherapy. There were no statistically significant differences in demographic and clinicopathologic characteristics between pCHT group and no pCHT group (all p > 0.05). Postoperative chemotherapy was not associated with a significant improvement in overall survival (OS) (Hazard ratio [HR] 0.815, 95% confidence interval [CI] 0.403-1.650; p = 0.474). Subgroup analyses demonstrated survival was equivalent between pCHT and no CHT group in ypT1N0 patients (HR 0.832, CI 0.222-3.121; p = 0.786) and ypT2N0 patients (HR 1.284, CI 0.564-2.924; p = 0.551). Multivariable analysis identified that clinical T stage independently influenced prognosis (cT3 vs. cT2: HR 2.875, 95% CI 0.998-8.281, p = 0.050; cT4 vs. cT2: HR 7.382, 95% CI 2.569-21.211, p < 0.001). In clinical T3-4 patients, there was an overall survival benefit for postoperative chemotherapy (HR 0.270, 95% CI 0.114-0.634; p = 0.006). No survival benefit of postoperative chemotherapy was identified in clinical T2 patients (HR 0.689, 95% CI 0.200-2.372; p = 0.579). Furthermore, postoperative chemotherapy was proved to be an independently positive prognostic factor for clinical T3-4 patients (HR 0.132, 95% CI 0.051-0.345; p < 0.001).

CONCLUSION

Postoperative chemotherapy might offer survival benefit to patients with ypT1-2N0 gastric cancer whose clinical T stage was T3-4 before preoperative chemotherapy.

Comparisons of prognosis prediction accuracy between modified and unmodified versions of 8th edition ypTNM

Background

The prognostic value of the existing 8^th edition post-neoadjuvant treatment (ypTNM) appears to be limited, and necessary reassessment and modification should be carried out as needed. This study aimed to compare the prognosis prediction accuracy of modified and unmodified versions of the 8^th edition ypTNM.

Methods

Esophageal cancer patients who had received neoadjuvant therapy from the Surveillance, Epidemiology, and End Results (SEER) database were included in this observational longitudinal study. The median follow-up time was 26 months. All-cause mortality was the outcome variable. Demographic and clinical variables were collected as covariates. Kaplan-Meier (log-rank test) and Cox proportional hazards models were conducted for developing modified ypTNM staging. The concordance index (C-index) was calculated to analyze the discriminative ability of modified ypTNM staging.

Results

Overall, 3,595 patients met inclusion criteria. The 8^th edition staging was not able to significantly discriminate between patients with ypT1- and ypT2-, ypT3- and ypT4-, ypN2- and ypN3- disease, respectively. Using the modified staging, we found that patients with ypT0–2 [hazard ratio (HR) =1.232; 95% confidence interval (CI): 1.053–1.441] and ypT3–4 (HR =1.257; 95% CI: 1.136–1.390) with grade III + IV had a significant risk of death compared to those with grade I + II. As was the case for the ypN0 (HR =1.295; 95% CI: 1.073–1.562) group with middle and upper tumor locations compared to those with low tumor location. The modified staging possessed better homogeneity in terms of the chi-square likelihood ratio (143.443 vs. 102.044), Akaike information criterion (AIC) (32,683.716 vs. 32,719.115), and Schwarz’s Bayesian criterion (SBC) (32,723.496 vs. 32,741.847), as well as better discriminatory ability (C-index of 0.577 vs. 0.560, P=0.045) compared to the 8^th edition staging.

Conclusions

Although the modified ypTNM staging system we created by incorporating tumor grade and location to the original T and N displayed certain prognosis prediction accuracy compared with the 8^th edition ypTNM staging, a larger sample size and prospective studies are needed to explore.

Prognostic value of pathological tumor regression grade in locally advanced gastric cancer: New perspectives from a single-center experience

BACKGROUND AND OBJECTIVE

Perioperative chemotherapy (PC) with radical surgery represents the gold standard of treatment for resectable advanced gastric cancer (GC). The prognostic value of pathological tumor regression grade (TRG) induced by neoadjuvant chemotherapy (NACT) is not clearly established. This study aimed to investigate the correlation between TRG and survival in GC.

METHODS

Patients affected by advanced GC undergoing PC and radical surgery were considered. TRG was assessed for each patient according to Becker's grading system. The correlation between TRG and survival was investigated.

RESULTS

One-hundred patients were selected; 25 showed a good response (GR) (TRG 1a/1b), while 75 had a poor response (PR) (TRG 2/3) to NACT. GR patients showed better disease-free survival (DFS) (52 vs. 19 months, p < .001) and disease-specific survival (DSS) (57 vs. 25 months, p < .0001) when compared to PR patients. On univariate analysis, TRG, lymph node ratio (LNR), tumor size, grading, and post-neoadjuvant therapy TNM stage were significantly correlated with survival. On multivariate analysis, TRG, LNR and tumor size were independent prognostic factors for DFS and DSS.

CONCLUSIONS

TRG, LNR, and tumor size are independent prognostic factors for DFS and DSS in patients with advanced GC undergoing NACT.

Type of preoperative therapy and stage-specific survival after surgery for rectal cancer: a nationwide population-based cohort study

Preoperative chemoradiation therapy (CRT) may induce downstaging in rectal cancer (RC). Short-course radiation therapy (SC-RT) with immediate surgery does not cause substantial downstaging. However, the TNM classification adds the “y” prefix in both groups to indicate possible treatment effects. We aim to compare stage-specific survival in these patients. RC patients treated with surgery only, preoperative SC-RT followed by surgery within 10 days, or preoperative CRT, and diagnosed between 2008 and 2014 were included in this population-based study. Clinicopathological and outcome characteristics were analyzed. The study included 11,925 patients. Large discrepancies existed between clinical and pathological stages after surgery only. Surgery-only patients were older with more comorbidities compared with SC-RT and CRT and had worse 5-year survival (64%, 76%, and 74%, respectively; p < 0.001). Five-year survival for stage I was similar after CRT and SC-RT (85% vs. 85%; p = 0.167) and comparable between CRT-treated patients with stage I and those reaching a pathological complete response (pCR; 85% vs. 89%; p = 0.113). CRT was independently associated with worse overall survival compared with SC-RT for stage II (HR 1.57 [95%CI 1.27–1.95]; p < 0.001) and stage III (HR 1.43 [95%CI 1.23–1.70]; p < 0.001). Stage I disease after CRT has an excellent prognosis, comparable with pCR and with same-stage SC-RT-treated patients without regression. Stage II or III after CRT has worse prognosis than after SC-RT with immediate surgery. TNM should take the impact of preoperative therapy type on stage-specific survival into account. In addition, clinical stage was a poor predictor of pathological stage.

Different prognostic implication of ypTNM stage and pTNM stage for gastric cancer: a propensity score-matched analysis

Background

Pathological stage is considered as the best prognosis indicator for gastric cancer. With the increasing use of neoadjuvant chemotherapy (NACT), the latest TNM staging included a new pathological stage of ypTNM for patients with NACT. However, no study has investigated if ypTNM stage has the same prognostic implication as pTNM stage for gastric cancer.

Methods

We retrospectively selected eligible patients within a prospectively maintained database containing all patients treated with gastric cancer in Peking University Cancer Hospital from 2007 to 2015 using overall survival as the outcome. Patients using ypTNM and pTNM were 1:1 matched by propensity scores (PS) calculated from a model containing variables associated with ypTNM use or survival. Overall survival was compared by unconditional Cox regression. Conventional multivariate analysis was conducted to corroborate PS matching results.

Results

1441 patients were included in the analysis with a median follow-up of 37 months (range = 2–106). The matched sample contained 756 patients. After PS matching, patients with specific ypTNM stage were 1.34 (95%CI = 1.05–1.72, P = 0.019) times more likely to die than patients with the same pTNM stage. Similar to the results of PS matching, multivariate Cox regression yielded a hazard ratio (HR) of 1.35 (95%CI = 1.09–1.67, P = 0.006). Subgroup analysis indicated this survival difference between ypTNM and pTNM stage varied by the specific TNM stage of patients. The HR was 3.44 (95%CI = 1.06–11.18, P = 0.040) and 1.28 (95%CI = 1.00–1.62, P = 0.048) for patients in stage I and III, respectively; whereas for stage II patients, no significant difference was observed (HR = 1.37, 95%CI = 0.78–2.38, P = 0.27).

Conclusion

Gastric cancer patients with specific ypTNM stage had worse prognosis compared to those at the same stage defined by pTNM.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5283-3) contains supplementary material, which is available to authorized users.

ypTNM category combined with AJCC tumor regression grade for screening patients with the worst prognosis after neoadjuvant chemoradiation therapy for locally advanced rectal cancer

Background

The purpose of this study was to investigate the value of the postsurgical pathological T and N (ypTN) category combined with the American Joint Committee on Cancer-tumor regression grade (AJCC-TRG) in evaluating the prognosis of neoadjuvant chemoradiation therapy (NeoCRT) for locally advanced rectal cancer (LARC) to screen for a subgroup of patients with the worst prognosis.

Patients and methods

In total, 265 patients with LARC were enrolled in the trial. All patients received NeoCRT. Total mesorectal excision was performed 6-8 weeks after the completion of radiotherapy. The surgical specimens were re-evaluated based on the AJCC-TRG (seventh edition) and the AJCC-tumor-node-metastasis (TNM; seventh edition) systems. We followed up these patients and calculated their overall survival (OS), disease-free survival (DFS), local recurrence-free survival (RFS), and distant metastasis (DM)-free survival (MFS) rates through the Kaplan-Meier analysis. The logrank test was further applied to evaluate the predictive value of the ypTN stage combined with AJCC-TRG for several survival indexes.

Results

The median follow-up period was 65.1 months. The 5-year OS, DFS, RFS, and MFS rates were 79.4%, 68.8%, 94.4%, and 76.5%, respectively. There were significant differences in OS, DFS, and MFS rates among different ypT+AJCC-TRG and ypN+AJCC-TRG subgroups. The 5-year OS, DFS, and MFS rates for ypT3-4+TRG 1 and ypT3-4+TRG2-3 subgroups were 73.9% vs 65.3%, 61.2% vs 52.9%, and 65.0% vs 61.5%, respectively. The 5-year OS, DFS, and MFS rates for ypN1-2+TRG 0-1 and ypN1-2+TRG2-3 subgroups were 64.8% vs 54.1%, 44.9% vs 41.7%, and 61.4% vs 46.3%, respectively.

Conclusion

The ypTNM category combined with the AJCC-TRG can more accurately evaluate the prognosis of patients with LARC and identify the subgroup of patients with the worst prognosis and high risk of developing DM, thereby demonstrating clinical significance in guiding individualized postoperative adjuvant therapy and follow-up for LARC.