Preoperative Therapy Regimen Influences the Incidence and Implication of Nodal Downstaging in Patients with Gastric Cancer

Nodal downstaging to ypN0 after neoadjuvant chemotherapy positively impacts on survival of cT4N+ GC/GEJ patients

BACKGROUND

The prognostic value of histomorphologic regression in primary gastric and gastroesophageal cancers (GC/GEJ) has been previously established, however, the impact of lymph node (LN) regression on survival still remains unclear.

METHODS

A prospectively maintained database was reviewed to identify cT4N+ gastric and gastroesophageal cancers (GC/GEJ) after NAC (neoadjuvant chemotherapy). Patients were categorized into two groups based on LN status: cN+/ypN0 (downstaged N0) and cN+/ypN+ (persistent N+), long-term survival were analyzed using Kaplan-Meier survival estimates.

RESULTS

In total, 125 patients with cT4N+ GC/GEJ underwent NAC followed by surgery were enrolled. A total of 39 patients (31.2%) had cN+/ypN0 (ypN0) disease, 86 patients (68.8%) had cN+/ypN+ (ypN+) disease. Prognosis in ypN+ patients was significantly worse than those in ypN0 group for 3- and 5-year overall survival (OS) (p < 0.05). The 3-year OS was 83%, 44% in ypN0 and ypN+ group, respectively. The 5-year OS was 75%, 35% in ypN0 and ypN+ group, respectively. Multivariable analysis suggested that multivisceral resection (hazard ratio [HR] = 0.33, 95% confidence interval [CI]: 0.14-0.76, p = 0.009), and ypN+ (HR = 3.42, 95% CI: 1.15-10.13, p =0.027) were independent prognostic factors for OS.

CONCLUSION

Nodal downstaging is an important hallmark representing the effectiveness of NAC for GC/GEJ, and it positively impacts on survival of these patients.

Duration of Perioperative Chemotherapy in Locally Advanced Gastric Cancer: A "Less Is More" Question When ypN0 Is Achieved

Backgrounds

Perioperative chemotherapy (PEC) and neoadjuvant chemotherapy (NAC) have become a vital part of locally advanced gastric cancer (LAGC) treatment, but the optimal duration of PEC has not been studied. The aim of this study was to demonstrate the possibility of duration reduction in PEC in the adjuvant chemotherapy (AC) phase for ypN0 patients.

Methods

We included LAGC patients who achieved ypN0 after NAC in our institution from 2005 to 2018. The risk/benefit of AC and other covariates were majorly measured by overall survival (OS) and progression-free survival (PFS). We developed a survival-tree-based model to determine the optimal PEC duration for ypN0 patients in different classes.

Results

A total of 267 R0 resection patients were included. There were 55 patients who did not receive AC. The 5-year OS was 74.34% in the non-AC group and 83.64% in the AC group with a significant difference (p = 0.012). Multivariate Cox regression revealed that both AC (AC vs. non-AC: HR, 0.49; 95%CI, 0.27–0.88; p = 0.018) and ypT stages (ypT3-4 vs. ypT0-2: HR, 2.00; 95%CI, 1.11–3.59; p = 0.021) were significant protective/risk factors on patients OS and PFS. A decision tree model for OS indicated an optimal four to six cycles of PEC, which was recommended for ypT0-2N0 patients, while a minimum of five PEC cycles was recommended for ypT3-4N0 patients.

Conclusion

AC treatment is still necessary for ypN0. The duration reduction could be applied for the ypT0-2N0 stage patients but may not be suitable for higher ypT stages and beyond. A multicenter-based study is required.

Validating a nodal regression system for gastric cancer: An ancillary cohort study of the GASTRODOC trial

BACKGROUND

To validate a nodal regression system for gastric cancer and to verify its impact on prognosis.

METHODS

This is an ancillary study which included 47 patients of the GASTRODOC trial. The dedicated pathologists of each Institute were invited to revise all the lymph nodes included in the surgical specimens in order to classify the regression according to the grading system proposed by Tsekrekos et al. The association of the nodal regression system and the clinico-pathological characteristics and prognosis were investigated.

RESULTS

According to the classification of Tsekrekos et al., there were 19 (40.4%) patients with grade a, 14 (29.8%) with grade b and 14 (29.8%) with grade c nodal regression. This regression system showed significant statistical associations with pathological N status (p < 0.001), residual tumor classification (p = 0.003) and Becker regression system (p = 0.011). At multivariable analysis only Tsekrekos' grading regression system was significantly associated with the PFS (HR 10.1, 95% CI 1.3-75.5; p = 0.025).

CONCLUSIONS

The analyzed nodal regression system is significantly associated with Becker's regression system and it has a strong correlation with prognosis.

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment-Oncological and Surgical Perspective

Simple Summary

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Therefore, further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Abstract

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. A favourable prognostic impact for ypN0 patients is observed, either due to truly negative LN before the start of therapy or because preoperative therapy achieved a pathologically complete nodal response. Ongoing trials investigating the extent of lymphadenectomy after neoadjuvant therapy will standardise the LN dissection from the multimodal therapy perspective. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.