Impact of tumor regression grade on recurrence after preoperative chemoradiation and gastrectomy for gastric cancer

Hyperactivation of mTOR/eIF4E Signaling Pathway Promotes the Production of Tryptophan-To-Phenylalanine Substitutants in EBV-Positive Gastric Cancer

Although messenger RNA translation is tightly regulated to preserve protein synthesis and cellular homeostasis, chronic exposure to interferon-γ (IFN-γ) in several cancers can lead to tryptophan (Trp) shortage via the indoleamine-2,3-dioxygenase (IDO)- kynurenine pathway and therefore promotes the production of aberrant peptides by ribosomal frameshifting and tryptophan-to-phenylalanine (W>F) codon reassignment events (substitutants) specifically at Trp codons. However, the effect of Trp depletion on the generation of aberrant peptides by ribosomal mistranslation in gastric cancer (GC) is still obscure. Here, it is shows that the abundant infiltrating lymphocytes in EBV-positive GC continuously secreted IFN-γ, upregulated IDO1 expression, leading to Trp shortage and the induction of W>F substitutants. Intriguingly, the production of W>F substitutants in EBV-positive GC is linked to antigen presentation and the activation of the mTOR/eIF4E signaling pathway. Inhibiting either the mTOR/eIF4E pathway or EIF4E expression counteracted the production and antigen presentation of W>F substitutants. Thus, the mTOR/eIF4E pathway exposed the vulnerability of gastric cancer by accelerating the production of aberrant peptides and boosting immune activation through W>F substitutant events. This work proposes that EBV-positive GC patients with mTOR/eIF4E hyperactivation may benefit from anti-tumor immunotherapy.

Profiling complete regression after pre-operative therapy in gastric cancer patients using clinical and pathological data

INTRODUCTION

The consistent use of pre-operative treatment before surgery for gastric cancer (GC) has resulted in increased rates of complete response. However, factors associated with response have been scantly investigated.

METHODS

Patients with GCs treated between 2017 and 2022 undergoing pre-operative treatment followed by resection were included. Clinicopathological data were analyzed for the association with tumor regression grades (TRG); secondary outcomes included the short-term overall (OS), disease-free (DFS) and disease specific survival (DSS).

RESULTS

Among 108 patients, 35.1% had an intestinal histotype GC, and 70.4% were treated with FLOT. Complete tumor regression (TRG1) was documented in 6.5% of patients. Univariable analyses documented that a higher pre-operative albumin (p = 0.04) and the expression of HER2 (p = 0.01) were associated to TRG1. In the multinominal regression model, the log-odds of being classified as TRG1 increased with the expression of HER2 by 170.247 times and with higher pre-operative albumin by 34.525 times, while with a higher Charlson Index and a diffuse hystotipe reduced it by 25.467 times and 3759.126 times, respectively. Among 49 patients (mean follow-up: 17.1 months), TRG1-2 was associated to better OS, DFS and DSS curves compared to TRG 3-5 (respectively p < 0.01, p 0.007 and p < 0.01), altogether with the reported negative impact of comorbidities in OS and DSS multivariable analyses (respectively p 0.04 and p 0.006). The random survival forest further confirmed the impact of HER2 and comorbidity on DSS.

CONCLUSION

A better clinical profile, HER2 expression and intestinal histotype significantly correlated with GC regression. A complete-major response was an independent factor for survival.

Comparison of the predictive value of pathological response at primary tumor and lymph node status after neoadjuvant chemotherapy in locally advanced gastric cancer

BACKGROUND

Preoperative chemotherapy has been increasingly used in locally advanced gastric cancer (LAGC). However, the prognostic factors are still insufficient. This study aimed to investigate the prognostic significance of pathological response of the primary tumor to neoadjuvant chemotherapy (NACT) and the lymph node status after NACT.

METHODS

Data from 160 patients with LAGC treated with NACT followed by gastrectomy and met the inclusion criteria between March 2016 and December 2019 were retrospectively reviewed. Pathological evaluation after NACT was based on the grade of pathological response of the primary tumor and the status of lymph node. Survival curves for overall survival (OS) and disease-free survival (DFS) 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

Among 160 selected cases, 90 had pathological response (PR), while 70 had no pathological response (nPR) to NACT. Smaller tumor size was presented in PR group, which also had lower level of signet ring cell features, compared to nPR group (all p < 0.05). Based on the status of lymph nodes, nodal status (-) group showed smaller tumor size, lower depth of tumor invasion, better differentiated degree, lower level of signet ring cell features, lower rate of lymphatic and venous invasion and less advanced ypTNM stage (all p < 0.05). Survival was equivalent between PR and nPR group (all p > 0.05), while patients with no lymph node metastasis had better DFS than that with lymph node metastasis (HR 0.301, 95% CI 0.194-0.468, p = 0.002). Multivariable Cox regression analysis identified that lymph node status after NACT was an independent prognostic factor associated with survival (OS: hazard ratio 1.756, 95% CI 1.114-3.278, p = 0.029; DFS: hazard ratio 1.901, 95% CI 1.331-3.093, p = 0.012).

CONCLUSION

Lymph node status is a potential independent prognostic factor for LAGC patients treated with NACT and may be more efficient than pathological response in primary tumor.

Tumor Regression Grade and Overall Survival following Gastrectomy with Preoperative Therapy for Gastric Cancer

BACKGROUND

Pre-/perioperative chemotherapy is well-established for management of locoregional gastric cancer (LRGC). The American Joint Committee on Cancer advocates histopathologic assessment of tumor regression grade (TRG) but does not endorse a specific schema. We sought to examine the prognostic value of the recently revised National Comprehensive Cancer Network (NCCN) definition of TRG specifying TRG0 as no disease in primary tumor or lymph nodes.

PATIENTS AND METHODS

Patients with clinical-stage T2+/N+/M0 LRGC receiving preoperative chemotherapy and curative-intent gastrectomy were identified (2000-2020). TRG using the current NCCN definition was retrospectively assigned. Factors associated with TRG were examined using ordinal logistic regression and overall survival (OS) was assessed using the Kaplan-Meier method and Cox regression.

RESULTS

Among 117 patients, the most common chemotherapy regimen was epirubicin, cisplatin, plus fluorouracil or capecitabine (ECF/ECX) (n = 48, 41%), followed by folinic acid, fluorouracil, and oxaliplatin (FOLFOX) (n = 30, 26%), and fluorouracil, leucovorin, oxaliplatin, plus docetaxel (FLOT) (n = 13, 11%). TRG3 was the most common histopathologic response (n = 68, 58%), followed by TRG2 (n = 25, 21%), TRG1 (n = 18, 15%), and, lastly, TRG0 (n = 6, 5.1%). The only preoperative factor independently associated with lower TRG was gastroesophageal junction tumor location (OR 0.24, p = 0.012). Higher TRG was independently associated with worse OS in a stepwise fashion (HR 1.49, p = 0.026). Posttreatment pathologic lymph node status was the strongest prognostic factor (HR 1.93, p = 0.026). Independent prognostic value of TRG and ypT stage could not be shown due to substantial overlap.

CONCLUSIONS

TRG using the contemporary NCCN definition is associated with OS in LRGC. TRG0 is uncommon but with excellent prognosis. ypN status is the strongest prognostic factor and the revised NCCN definition acknowledging this is appropriate.

Comparison of response evaluation criteria in solid tumors and tumor regression grade in evaluating the effect of preoperative systemic therapy of gastric cancer

BACKGROUND

Both Response Evaluation Criteria in Solid Tumors (RECIST) and tumor regression grade (TRG) play key roles in evaluating tumor response. We analyzed the consistency of TRG and RECIST 1.1 for gastric cancer (GC) patients and compared their prognostic values.

METHODS

Patients with GC who received preoperative chemotherapy or chemoimmunotherapy and had records of TRG from December 2013 to October 2021 were enrolled retrospectively. TRG 0-1 and 2-3 are considered as corresponding to complete response (CR)/partial response (PR) and stable disease (SD)/progress disease (PD) in RECIST 1.1, respectively. The primary endpoints were disease-free survival (DFS) and overall survival (OS). The consistency of RECIST and TRG was examined by kappa statistics. Survival analysis was performed using the Kaplan Meier method.

RESULT

One hundred fifty seven GC patients were enrolled, including 125 with preoperative chemotherapy and 32 with chemoimmunotherapy. Among them, 56 patients had measurable lesions. Only 19.6% (11/56) of the patients had consistent results between RECIST 1.1 and TRG. TRG was correlated with both OS and DFS (P = 0.02 and 0.03, respectively) while response according to RECIST1.1 was not (P = 0.86 and 0.23, respectively). The median DFS had not reached in the TRG 0-1 group and was 16.13 months in TRG 2-3 group. TRG 2-3 was associated with young age and peritoneal or liver metastasis. Besides, preoperative chemoimmunotherapy had a significantly higher pCR rate than chemotherapy alone (34.4% vs 8.0%, P < 0.001).

CONCLUSION

TRG was in poor agreement with RECIST 1.1. TRG was better than RECIST 1.1 in predicting DFS and OS for GC patients who received preoperative therapy.

Lymph node ratio is a prospective prognostic indicator for locally advanced gastric cancer patients after neoadjuvant chemotherapy

Background

The accuracy of lymph node ratio (LNR) as a prognostic index remains to be proven for gastric cancer patients after neoadjuvant chemotherapy (NACT). This study sought to investigate the prognostic value of LNR in locally advanced gastric cancer (LAGC) patients after NACT.

Methods

LAGC patients with clinical TNM stages 2–3, Her2(−), and Eastern Cooperative Oncology Group, scores 0–2 are routinely scheduled with NACT. Patients with LAGC after NACT and surgical operation between January 2012 and October 2020 were retrospectively reviewed. The correlation between LNR and survival was investigated.

Results

Overall, 148 patients were enrolled: 103 with low-LNR (LNR ≤ 30%) and 45 with high-LNR (LNR > 30%). Approximately, 50.5% and 24.4% patients responded to NACT at the primary site in the low-LNR and high-LNR groups, respectively. The overall survival (OS) and progression-free survival (PFS) of low-LNR group were considerably better than those of high-LNR group (3-year OS: 81.9% vs 18.5%, P < 0.001; 3-year PFS: 72.6% vs 13.5%, P < 0.001). In the low-LNR group, OS and PFS were superior in patients with tumor regression grade (TRG) 0–2 than in those with TRG 3 (3-year OS: 89.2% vs 73.2%, P = 0.086; 3-year PFS: 80.3% vs 66.5%, P = 0.036). In association with OS and PFS, the degree of tumor differentiation, TRG, and LNR were identified as predictive factors, and LNR was identified as the independent prognostic factor in univariate and multivariate analyses, respectively.

Conclusions

LNR is a prospective index of prognosis in patients with LAGC after NACT.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02725-9.

Prognostic value and clinicopathological correlation of the tumor regression grade in neoadjuvant chemotherapy for gastric adenocarcinoma: a retrospective cohort study

BACKGROUND

Neoadjuvant chemotherapy (NACT) and radical gastrectomy are the gold standard treatments for resectable advanced gastric cancer (GC). However, the prognostic value of the pathological tumor regression grade (TRG) of NACT remains controversial. This retrospective study aimed to investigate the correlation between the TRG after NACT and clinicopathological features as well as its prognostic value in advanced GC.

METHODS

In total, 551 patients with GC who received NACT combined with surgical resection at the Zhejiang Cancer Hospital from April 2004 to December 2019 were included. The demographic characteristics, treatment response, tumor characteristics, treatment regimens, and survival data were reviewed from the medical records of all patients. The Chi-square test was used to analyze the correlation between TRG and clinicopathological factors. Kaplan-Meier univariate analysis and Cox regression multivariate analysis were used to determine the independent risk factors affecting the prognosis of GC patients.

RESULTS

Among the 551 patients with advanced GC who accepted NACT treatment, 14 were determined to be in TRG 0, 98 in TRG 1, 257 in TRG 2, and 182 in TRG 3. Also, TRG was significantly correlated with the cT stage (P=0.015), ypT stage (P<0.001), ypN stage (P<0.001), ypTNM stage (P<0.001), vascular tumor thrombus (P<0.001), Borrmann classification (P=0.042), and lymph node ratio (LNR) (P<0.001). Furthermore, patients who had a good pathological response to NACT had a better prognosis, with a 3-year overall survival (OS) of 70.9% versus 48.8% in patients who had a poor pathological response. We also found that TRG (P=0.042, HR =1.65) was an independent prognostic factor affecting the OS of GC patients.

CONCLUSIONS

TRG plays a significant role in the prognostic value in neoadjuvant chemotherapy for gastric adenocarcinoma. Patients with higher cT stage, higher levels of pre-CA199 and pre-CA125 may have worse pathological response.

Comparison of tumor regression grading systems for locally advanced gastric adenocarcinoma after neoadjuvant chemotherapy

BACKGROUND

Current tumor regression grade (TRG) evaluations are based on various systems which brings confusion for oncologists and pathologists when interpreting results. The recent six-tier system (JGCA2017-TRG) recommended by the Japanese Gastric Cancer Association (JGCA) is worth investigating, as four-tier TRG systems are favored in various parts of the world.

AIM

To compare the predictive accuracies of five published TRG systems.

METHODS

Data were retrospectively collected from patients with locally advanced gastric cancer (LAGC) who underwent neoadjuvant chemotherapy followed by D2 Lymphadenectomy between January 2005 and January 2014 at our institution. Outcomes were overall survival (OS) and disease-free survival (DFS), which were evaluated separately using the following TRG systems: JGCA2017, JGCA, Becker, AJCC/CAP, and Mandard.

RESULTS

All five published TRG systems were independent predictors for OS and DFS. Concordance indices of the JGCA2017, JGCA, Becker, AJCC/CAP-TRG, and Mandard systems were 0.651/0.648 0.652/0.649, 0.693/0.695, 0.688/0.685, and 0.674/0.675 for OS and DFS, respectively. The four-tier Becker system showed the highest c-index, which was significantly greater than that of the six-tier JGCA2017 and five-tier JGCA systems (P < 0.05 in OS and DFS). When residual tumor percentages were reset as: “no residual tumor”, < 10%, < 100%, and “no response”, the rearranged cutoff values achieved a maximum c-index with 0.728 for OS and 0.737 for DFS, which was superior to the other five systems.

CONCLUSION

The newly introduced six-tier JGCA-TRG system cannot increase prognostic stratification. The four-tier Becker system is more suitable for LAGC patients. A population-based study is warranted to define the optimal criterion for TRG in LAGC patients.

Determinants of Survival for Patients with Neoadjuvant-Treated Node-Negative Gastric Cancer

BACKGROUND

This study sought to determine prognostic markers for disease recurrence and survival in a cohort of neoadjuvant-treated, node-negative gastric cancer patients (ypT0-4N0M0).

METHODS

Clinicopathologic data from patients treated with neoadjuvant therapy followed by curative-intent gastrectomy at the University of Texas MD Anderson Cancer Center from 1995 to 2017 were evaluated. Patients with AJCC TNM stage ypT0-4N0M0 were considered for analysis.

RESULTS

The inclusion criteria were met by 212 patients with a mean age of 58.3 years. Of these patients, 60 % were male, 53 % were Caucasian, 87 % received chemoradiation, and 13 % received chemotherapy. The findings showed a median overall survival (OS) rate of 11.3 years, a 5-year survival rate of 72 %, and a 10-year survival rate of 57 %. During a median follow-up period of 5.5 years, 38.2 % of the patients died. In the multivariable analysis, ypT4-stage and nodal yield fewer than 16 were significantly associated with reduced OS. Cancer classified as ypT4 had more aggressive biologic traits, including lymphovascular and perineural invasion, and was treated more aggressively with total gastrectomy and additional organ resection despite frequent positive margins. Depth of invasion remained significantly associated with worse outcome after the analysis controlled for nodal yield and possible stage migration. Compared with ypT0-3 tumors, ypT4 cancers were associated with significantly more recurrences (13 % vs. 45 %; p < 0.05), and the primary modes of failure for ypT4 lesions were local recurrence and peritoneal metastases (88 % of recurrences).

CONCLUSIONS

Depth of primary tumor invasion and nodal yield were significantly associated with OS among the patients with ypT0-4N0M0 gastric cancer. Serosal invasion (ypT4) was associated with a high rate of peritoneal recurrence, and trials of intraperitoneal therapy targeting these patients should be considered.