Prognostic Relevance of Lymph Node Regression After Neoadjuvant Chemoradiation for Esophageal Cancer

Nodal Downstaging of Esophageal Cancer After Neoadjuvant Therapy: A Cohort Study and Meta-Analysis

BACKGROUND

In esophageal cancer, the ypN0 status after induction therapy could be categorized into two primary groups: "natural N0" (cN0/ypN0) and "down-staged N0" (cN+/ypN0). The assessment of cN status is typically based on clinical imagination or pathological regression. However, there is no standardized method for evaluating cN/ypN status. This study aims to investigate the prognosis of patients with cN+/ypN0 using both assessment methods through a cohort study and meta-analysis.

METHODS

A prospectively maintained database encompassing esophageal cancer patients undergoing induction therapy followed by radical esophagectomy was comprehensively reviewed. The prognostic significance of cN+/ypN0 across two evaluation methods was quantified. Additionally, a meta-analysis using data from previous studies was conducted.

RESULTS

578 patients were identified from the cohort analysis, with 342 classified as ypN0 and 236 as ypN+. When evaluated with clinical imagination, patients with cN+/ypN0 had survival outcomes comparable to those with natural N0 but significantly better than those with ypN+ (p < 0.001). Using pathological nodal regression, cN+/ypN0 patients showed superior overall survival compared to ypN+ patients (p = 0.0043), although their disease-free survival was notably inferior to that of natural N0 patients (p = 0.0088). A meta-analysis of 20 previous studies confirmed the prognostic value of cN+/ypN0 status in both clinical imagination and pathological regression.

CONCLUSIONS

For esophageal cancer patients receiving neoadjuvant, cN+/ypN0 status, assessed through both clinical imagination and pathological regression, serves as a significant prognostic factor. It holds precedence over ypN+ yet falls short of the natural N0. The pre-treatment categorizations warrant recognition as a novel and pertinent staging metric.

Prognostic role of lymph node regression in patients with esophageal cancer undergoing neoadjuvant therapy

Purpose

To clarify the prognostic value of lymph node regression (LNR) status including the lymph node regression grade (LNRG) and N downstaging in patients with esophageal cancer receiving neoadjuvant therapy based on available evidence.

Methods

Several databases were searched up to 25 March 2024. The main outcomes included overall survival (OS), disease-free survival (DFS) and cancer-specific survival (CSS). Hazard ratios (HRs) and 95% confidence intervals (CIs) were combined. Subgroup analyses based on the neoadjuvant therapy and pathological type were also conducted.

Results

In total, 14 retrospective studies with 3,212 participants were included. Nine and five studies explored the relationship between LNRG and N downstaging and survival, respectively. Pooled results indicated that complete LNR predicted significantly improved OS (HR = 0.47, 95% CI: 0.41-0.55, P < 0.001) and DFS (HR = 0.42, 95% CI: 0.32-0.55, P < 0.001) and subgroup analysis based on neoadjuvant therapy and pathological type manifested similar results. Besides, N downstaging was also significantly related to improved OS (HR = 0.40, 95% CI: 0.21-0.77, P = 0.006) and CSS (HR = 0.27, 95% CI: 0.12-0.60, P < 0.001).

Conclusion

LNR could serve as a novel and reliable prognostic factor in patients with esophageal cancer receiving neoadjuvant therapy and complete LNR and N downstaging predict better survival.

Role of pathological tumor regression grade of lymph node metastasis following neoadjuvant chemotherapy in locally advanced gastric cancer

AIMS

To confirm whether the pathological response of lymph node metastasis (LNM) to neoadjuvant chemotherapy (NCT) can predict the prognosis of patients with gastric cancer (GC).

METHODS

A total of 979 patients with locally advanced GC were included. χ2 test was used to analyze the relationship between LNM TRG and clinicopathological factors. Cox proportional hazards model was used to analyze the relationship between LNM TRG, clinicopathological factors, and overall survival (OS).

RESULTS

A total of 21,162 lymph nodes were evaluated, with 237 patients (35.4%) in the response group and 433 patients (64.6%) in the non-response group. The non-responsive group was strongly associated with higher ypT, ypN, ypTNM, primary tumor (PT) TRG (all p < 0.001), positive cancer nodules (p = 0.001), and more distant LNM location (p < 0.001). Patients with the same PT TRG but different LNM TRG had different prognosis. There was no difference in OS between the responding and non-responding groups of LNM at location 2, 3, and M. YpN, tumor location, and LNM location were independent prognostic factors.

CONCLUSIONS

The combination of LNM TRG and PT TRG could better predict patient prognosis. Lymph node dissection should be routinely performed after NCT to provide the reference of radical resection.

Identification of Optimal Parameters for Assessing Lymph Node Status of Patients with Esophageal Squamous Cell Carcinoma After Neoadjuvant Chemoradiotherapy

BACKGROUND

This study aimed to compare the prognostic discrimination power of pretreatment pathologic N stage (prepN), lymph node tumor regression grade (LNTRG), and posttreatment pathologic N (ypN) category for esophageal squamous cell carcinoma (ESCC) patients who received neoadjuvant chemoradiotherapy (nCRT) plus surgery.

METHODS

The study reviewed 187 ESCC patients from two medical centers who underwent nCRT plus surgery. Pathologic LNTRG was defined by the proportion of viable tumor area within the tumor bed in lymph nodes (LNs). An average LNTRG then was calculated by averaging the tumor regression grade (TRG) score of all resected LNs. Lymph nodes containing regression changes or vital tumor cells were used for interpretation of the prepN stage, which reflects the estimated number of originally involved LNs.

RESULTS

The ypN, prepN, and LNTRG categories had significant prognostic stratification power (p < 0.001, log-rank test). Multivariable cox regression showed that all three categories were independent prognostic factors of disease-free survival (DFS) (p < 0.05). The LNTRG category showed a better prognostic value for DFS prediction than the ypN and prepN categories (Akaike information criterion [AIC]: LNTRG [933.69], ypN [937.56], prepN [937.45]). Additionally, the superior predictive capacity of the LNTRG category was demonstrated by decision curve analysis. Similar results were discovered for patients with remaining diseased LNs.

CONCLUSIONS

The three staging categories had prognostic relevance for DFS, with the LNTRG category seeming to have better prognostic indication power. Comprehensive consideration of the ypN status, prepN status, and LN regression may allow for better prognostic stratification of patients.

Pathologic Lymph Node Regression After Neoadjuvant Chemotherapy Predicts Recurrence and Survival in Esophageal Adenocarcinoma: A Multicenter Study in the United Kingdom

PURPOSE

There is limited evidence regarding the prognostic effects of pathologic lymph node (LN) regression after neoadjuvant chemotherapy for esophageal adenocarcinoma, and a definition of LN response is lacking. This study aimed to evaluate how LN regression influences survival after surgery for esophageal adenocarcinoma.

METHODS

Multicenter cohort study of patients with esophageal adenocarcinoma treated with neoadjuvant chemotherapy followed by surgical resection at five high-volume centers in the United Kingdom. LNs retrieved at esophagectomy were examined for chemotherapy response and given a LN regression score (LNRS)-LNRS 1, complete response; 2, <10% residual tumor; 3, 10%-50% residual tumor; 4, >50% residual tumor; and 5, no response. Survival analysis was performed using Cox regression adjusting for confounders including primary tumor regression. The discriminatory ability of different LN response classifications to predict survival was evaluated using Akaike information criterion and Harrell C-index.

RESULTS

In total, 17,930 LNs from 763 patients were examined. LN response classified as complete LN response (LNRS 1 ≥1 LN, no residual tumor in any LN; n = 62, 8.1%), partial LN response (LNRS 1-3 ≥1 LN, residual tumor ≥1 LN; n = 155, 20.3%), poor/no LN response (LNRS 4-5; n = 303, 39.7%), or LN negative (no tumor/regression; n = 243, 31.8%) demonstrated superior discriminatory ability. Mortality was reduced in patients with complete LN response (hazard ratio [HR], 0.35; 95% CI, 0.22 to 0.56), partial LN response (HR, 0.72; 95% CI, 0.57 to 0.93) or negative LNs (HR, 0.32; 95% CI, 0.25 to 0.42) compared with those with poor/no LN response. Primary tumor regression and LN regression were discordant in 165 patients (21.9%).

CONCLUSION

Pathologic LN regression after neoadjuvant chemotherapy was a strong prognostic factor and provides important information beyond pathologic TNM staging and primary tumor regression grading. LN regression should be included as standard in the pathologic reporting of esophagectomy specimens.

Pathological regression of primary tumour and metastatic lymph nodes following chemotherapy in resectable OG cancer: pooled analysis of two trials

BACKGROUND

No definitive largescale data exist evaluating the role of pathologically defined regression changes within the primary tumour and lymph nodes (LN) of resected oesophagogastric (OG) adenocarcinoma following neoadjuvant chemotherapy and the impact on survival.

METHODS

Data and samples from two large prospective randomised trials (UK MRC OE05 and ST03) were pooled. Stained slides were available for central pathology review from 1619 patients. Mandard tumour regression grade (TRG) and regression of tumour within LNs (LNR: scored as present/absent) were assessed and correlated with overall survival (OS) using a Cox regression model. An exploratory analysis to define subgroups with distinct prognoses was conducted using a classification and regression tree (CART) analysis.

RESULTS

Neither trial demonstrated a relationship between TRG score and the presence or absence of LNR. In univariable analysis, lower TRG, lower ypN stage, lower ypT stage, presence of LNR, presence of well/moderate tumour differentiation, and absence of tumour at resection margin were all associated with better OS. However, the multivariable analysis demonstrated that only ypN, ypT, grade of differentiation and resection margin (R0) were independent indicators of prognosis. Exploratory CART analysis identified six subgroups with 3-year OS ranging from 83% to 22%; with ypN stage being the most important single prognostic variable.

CONCLUSIONS

Pathological LN stage within the resection specimen was the single most important determiner of survival. Our results suggest that the assessment of regression changes within the primary tumour or LNs may not be necessary to define the prognosis further.

DOES NEOADJUVANT CHEMORADIOTHERAPY FOR ESOPHAGEAL AND GASTROESOPHAGEAL JUNCTION CANCER PATIENTS AFFECT POSTOPERATIVE OUTCOMES? A STUDY USING THE BECKER TUMOR REGRESSION GRADE SYSTEM AND LYMPH NODE REGRESSION

BACKGROUND

The effect of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced esophageal cancer can be determined by assessing the Becker tumor regression grade in the primary tumor, as well as in lymph nodes.

AIMS

The aim of this study was to investigate the anatomopathological changes caused by neoadjuvant chemoradiotherapy and their impact on clinical parameters. Specifically, we analyzed the Becker tumor regression grade, lymph node status, and regression changes and evaluated their association with the Clavien-Dindo classification of surgical complications and overall patient survival.

METHODS

This is a retrospective and observational study including 139 patients diagnosed with adenocarcinoma or squamous cell carcinoma of the esophagus and treated with either neoadjuvant chemoradiotherapy followed by surgery or surgery alone. For the 94 patients who underwent neoadjuvant chemoradiotherapy, we evaluated tumor regression by Becker tumor regression grade in primary tumors. We also analyzed lymph node status and regression changes on lymph nodes with or without metastases. Overall survival analysis was performed using Kaplan-Meier curves.

RESULTS

Becker tumor regression grade is associated with lower lymphatic permeation (p<0.01) and vascular invasion (p<0.001), but not with lymph node regression rate (p=0.10). Clavien-Dindo classification was associated neither with lymph node regression rate (odds ratio=0.784, p=0.795) nor with tumor regression grade (p=0.68). Patients who presented with lymphatic permeation and vascular invasion had statistically significantly lower median survival (17 vs. 30 months, p=0.006 for lymphatic permeation, and 14 vs. 29 months, p=0.024 for vascular invasion).

CONCLUSION

In our series, we were unable to demonstrate an association between Becker tumor regression grade and lymph node regression rate with any postoperative complications. Patients with lower lymphatic permeation and vascular invasion have higher overall survival, correlating with a better response in the Becker tumor regression grade system.

Can patients with good tumor regression grading after neoadjuvant chemoradiotherapy be exempted from lateral lymph node dissection?

OBJECTIVE

To investigate whether lateral lymph node (LLN) dissection (LLND) can be exempted in patients with good tumor regression grading (TRG) after neoadjuvant chemoradiotherapy (nCRT)?

METHODS

A retrospective study was conducted on consecutive patients with advanced rectal cancer who underwent nCRT and total mesorectal resection plus selective LLND at our institution. The primary outcomes are the relationship between LLN metastasis (LLNM) and magnetic resonance imaging TRG (mrTRG) and the relationship between LLNM and pathological TRG (pTRG).

RESULTS

A total of 91 patients were included, of which 24 patients (26.4%) had LLNM, 67 patients (73.6%) had no LLNM. There were significant differences of the maximum short-axis of LLN before and after nCRT, short-axis reduction rate of the LLN with maximum short-axis, length diameter reduction rate of primary tumor, mrTRG, and pTRG between the two groups. Multivariate logistic regression showed that mrTRG (P = 0.026) and pTRG (P = 0.013) were independent predictors for LLNM. The combination used by mrTRG and the maximum short-axis of LLNs ≥ 8 mm before nCRT and the maximum short-axis of LLN ≥ 5 mm after nCRT achieved specificity of 0.970, positive predictive value (PPV) of 0.867, and negative predictive value (NPV) of 0.855. The same combination used by pTRG achieved the specificity of 0.970, PPV of 0.857 and NPV of 0.844.

CONCLUSION

The suspected positive LLNs tend to be sterilized by nCRT in patients who have a very good response to nCRT. It is rational to avoid LLND in patients whose primary tumor and LLNs both show good response to nCRT.

Pathological complete response in multimodal treatment of esophageal cancer: a retrospective cohort study

To evaluate pathological complete response (pCR, ypT0ypN0) after neoadjuvant treatment compared with non-complete response (non-CR) in patients with esophageal cancer (EC), and 393 patients were retrospectively analyzed. Survival probability was analyzed in patients with: (i) pCR vs non-CR; (ii) complete response of the primary tumor but persisting lymphatic metastases (non-CR-T0N+) and (iii) pCR and tumor-free lymphnodes exhibiting signs of postneoadjuvant regression vs. no signs of regression. (i) Median overall survival (mOS) was favorable in patients with pCR (pCR: mOS not reached vs. non-CR: 41 months, P < 0.001). Multivariate analysis revealed that grade of regression was not an independent predictor for prolonged survival. Instead, the achieved postneoadjuvant TNM-stage (T-stage: Hazard ratio [HR] ypT3-T4 vs. ypT0-T2: 1.837; N-stage: HR ypN1-N3 vs. ypN0: 2.046; Postneoadjuvant M-stage: HR ypM1 vs. ycM0: 2.709), the residual tumor (R)-classification (HR R1 vs. R0: 4.195) and the histologic subtype of EC (HR ESCC vs. EAC: 1.688) were prognostic factors. Patients with non-CR-T0N+ have a devastating prognosis, similar to those with local non-CR and lymphatic metastases (non-CR-T + N+) (non-CR-T0N+: 22.0 months, non-CR-T + N-: mOS not reached, non-CR-T + N+: 23.0 months; P-values: non-CR-T0N+ vs. non-CR-T + N-: 0.016; non-CR-T0N+ vs. non-CR-T + N+: 0.956; non-CR-T + N- vs. non-CR-T + N+: <0.001). Regressive changes in lymphnodes after neoadjuvant treatment did not influence survival-probability in patients with pCR (mOS not reached in each group; EAC-patients: P = 0.0919; ESCC-patients: P = 0.828). Particularly, the achieved postneoadjuvant ypTNM-stage influences the survival probability of patients with EC. Patients with non-CR-T0N+ have a dismal prognosis, and only true pathological complete response with ypT0ypN0 offers superior survival probabilities.

Is Tumor Regression Grade Sufficient to Predict Survival in Esophageal Cancer with Trimodal Therapy?

BACKGROUND

This study aimed to assess the predictive value of tumor regression grade (TRG) and nodal status on survival in esophageal carcinoma with neoadjuvant chemoradiotherapy (nCRT).

METHODS

Tumor pathologic regression and nodal status were assessed. Differences in survival stratified by TRG or nodal status were analyzed using the Kaplan-Meier method and log-rank test. The prognostic value of TRG and nodal status were analyzed using univariate and multivariate Cox proportional hazards methods.

RESULTS

From July 2016 to June 2019, 253 patients with esophageal cancer underwent nCRT followed by surgery. Significant differences were presented in survival according to nodal status but not TRG. Multivariate analysis showed that nodal status and not TRG was the only independent predicter for overall survival (HR: 3.550, 95% CI: 2.264-5.566, P < 0.001) and disease-free survival (HR: 2.801, 95% CI: 1.874-4.187, P < 0.001). The modified TRG system combining tumor regression with nodal status stratified patients survival with good discrimination.

CONCLUSIONS

Lymph node status impacts more importantly than TRG on survival for patients with esophageal cancer undergoing nCRT plus esophagectomy. The modified TRG system may facilitate postoperative treatment decisions and survival surveillance.

Pathological Regression of Lymph Nodes Better Predicts Long-term Survival in Esophageal Cancer Patients Undergoing Neoadjuvant Chemotherapy Followed by Surgery

OBJECTIVE

To evaluate pathological response to NAC in metastatic LNs, and assess its clinical prognostic significance in patients with EC.

SUMMARY OF BACKGROUND DATA

The pathological response to preoperative treatment is commonly evaluated in the PT. However, LN metastases strongly correlate with systemic micro-metastases. Thus, pathological evaluation of LN response could more accurately predict prognosis in EC patients undergoing NAC before surgery.

METHODS

We enrolled 371 consecutive patients who underwent triplet NAC followed by surgery for EC between January 2010 and December 2016. Pathological LN regression grade was defined by the proportion of viable tumor area within the whole tumor bed area for all metastatic LNs: grade I, >50%; II, 10%-50%; III, <10%; and IV, 0%. We analyzed the correlation of grade with clinico-pathological parameters.

RESULTS

Among 319 patients with clinically positive LNs, pathological LN regression grades were I/II/III/IV in 115/51/58/95 patients, and 191 patients (59.9%) showed discordance between the PT and LN pathological regression grades. LN regression grade significantly correlated with cN positive number, ypTNM, lymphovascular invasion, and clinical/pathological PT response. Multivariate analysis for recurrence-free survival revealed that LN regression grade [hazard ratio (HR) = 2.25, P < 0.001], ypT (HR = 1.65, P = 0.005), and ypT (HR = 1.62, P = 0.004) were independent prognostic factors, but not pathological PT regression grade (P = 0.67).

CONCLUSIONS

Compared to PT response, pathological LN response better predicted long-term survival in EC patients who received NAC plus curative surgery.

Grading der Tumorregression gastrointestinaler Karzinome nach neoadjuvanter Therapie

Prä- oder perioperative Chemo- oder Radiochemotherapie und anschließende Resektion ist die Standardtherapie von lokal fortgeschrittenem Ösophagus‑, Magen- und Rektumkarzinom. Eine Tumorregressionsgraduierung (TRG, auch Tumorregressionsgrad) kategorisiert das Ausmaß der regressiven Veränderungen nach neoadjuvanter Behandlung. Für gastrointestinale Karzinome existieren mehrere TRG-Systeme, die sich entweder auf das Ausmaß der therapieinduzierten Fibrose im Verhältnis zum Resttumor oder den geschätzten Anteil des Resttumors im Bereich des ehemaligen Tumorareals beziehen. Ein ideales TRG-System zeigt eine signifikante Interobserverübereinstimmung und bietet relevante prognostische Informationen – in den meisten Fällen ist eine vollständige oder nahezu vollständige Regression nach neoadjuvanter Therapie mit verbesserter Prognose verbunden. In diesem Review werden die am häufigsten verwendeten TRG-Systeme für gastrointestinale Karzinome vorgestellt und diskutiert. Zudem werden aktuelle Punkte wie die Standardisierung der Angabe von TRGs und die Thematik der Regression bei Lymphknotenmetastasen im Kontext eines TRG-Systems behandelt.

Impact of neoadjuvant chemotherapy on nodal regression and survival in oesophageal adenocarcinoma

BACKGROUND

The prognostic value of lymph node regression (LNR) following neoadjuvant chemotherapy (nCT) for oesophageal and gastro-oeosphageal adenocarcinoma remains unclear. This study aimed to characterise the long-term survival outcomes of LNR in patients having resectional surgery after nCT.

METHODS

This study included patients undergoing oesophagectomy or extended total gastrectomy for oesophageal and junctional tumours (Siewert types 1,2,3) at the Queen Elizabeth Hospital Birmingham from 2012 to 2018. Lymph nodes retrieved at surgery were examined for evidence of a response to chemotherapy. Patients were classified as lymph node-negative (either negative nodes with no evidence of previous tumour involvement or negative with evidence of complete regression) or positive with either partial or no response.

RESULTS

This study identified 183 patients who received nCT, of which 71% (130/183) had positive lymph nodes. Of these 130 patients, 44% (57/130) had a lymph node response and 56% (73/130) did not. The remaining 53 patients (29.0%) had negative lymph nodes with no evidence of tumour. Lymph node responders had a significant survival benefit compared to patients without lymph node response, but shorter than those with negative lymph nodes (median: 27 vs 18 vs NR months, p < 0·001). On multivariable analysis, lymph node responders had an improved overall (Hazard ratio (HR): 0.86, 95% CI: 0.80-0.92, p < 0.001) and recurrence-free (HR: 0.90, 95% CI: 0.82-0.98, p = 0.030) survival.

CONCLUSION

Lymph node regression is an important prognostic factor, warranting closer evaluation over primary tumour response to help with planning further adjuvant therapy in these patients.

Interobserver agreement of a gastric adenocarcinoma tumor regression grading system that incorporates assessment of lymph nodes

Perioperative chemotherapy is increasingly used in combination with surgery for the treatment of patients with locally advanced, resectable gastric cancer. Histologic tumor regression grade (TRG) has emerged as an important prognostic factor; however, a common standard for its evaluation is lacking. Moreover, the clinical significance of regressive changes in metastatic lymph nodes (LNs) remains unclear. We conducted an international study to examine the interobserver agreement of a TRG system that is based on the Becker system for the primary tumors and additionally incorporates regression grading in LNs. Twenty observers at different levels of experience evaluated the TRG in 60 histologic slides (30 primary tumors and 30 LNs) based on the following criteria: for primary tumors, grade 1 represented complete response (no residual tumor), grade 2 represented <10%, grade 3 represented 10-50%, and grade 4 represented >50% residual tumor, as described by Becker et al. For LNs, grade "a" represented complete, grade "b" represented partial, and grade "c" represented no regression. The interobserver agreement was estimated using the Kendall's coefficient of concordance (W). Regarding primary tumors, agreement was good irrespective of the level of experience, reaching a W-value of 0.70 overall, 0.71 among subspecialized, and 0.71 among nonsubspecialized observers. Regarding LNs, interobserver agreement was moderate to good, with W-values of 0.52 overall, 0.64 among subspecialized, and 0.45 among nonsubspecialized observers. These findings indicate that the combination of the Becker TRG system with a three-tiered grading of regression in LNs generates a system that is reproducible. Future studies should investigate whether the additional information of TRG in LNs adds to the prognostic value of histologic regression grading in gastric cancer specimens.

Lymph Node Regression to Neoadjuvant Chemoradiotherapy in Patients with Locally Advanced Rectal Cancer: Prognostic Implication and a Predictive Model

AIM

Currently, few studies have focused on the prognostic impact of lymph node regression to neoadjuvant chemoradiotherapy (NCRT) in rectal cancer. This study aimed to explore the prognostic impact of lymph node regression grade (LRG) in patients with locally advanced rectal cancer (LARC) following NCRT and radical surgery and develop a predictive nomogram for disease-free survival (DFS).

METHODS

LARC patients undergoing NCRT and radical surgery between 2013 and 2014 were enrolled and divided into LRG low (≤ 2), middle (3-9), and high (≥ 10) groups. Clinicopathological characteristics and survival outcomes were compared. Predictors for DFS were identified by Cox regression analysis, and a nomogram was constructed.

RESULTS

A total of 257 LARC patients were eligible, including LRG low (n = 149), middle (n = 59), and high (n = 49) groups. Higher LRG score was associated with higher TRG, more advanced ypT and ypN stages, and poorer OS and DFS (all P < 0.001). Cox regression analysis demonstrated that tumor differentiation (poor and anaplastic, HR = 2.048, P = 0.048), ypTNM stage (HR = 2.389, P = 0.015), and LRG-sum (HR = 1.020, P = 0.029) were independent prognostic determinants for DFS after NCRT. A nomogram for DFS was developed with a C-index of 0.68 (95%CI 0.64-0.72).

CONCLUSION

LRG is an important prognostic indicator for DFS in LARC patients after NCRT. A predictive nomogram based on LRG was developed to guide more tailored adjuvant treatment and surveillance.

Brazilian Group of Gastrointestinal Tumours' consensus guidelines for the management of oesophageal cancer

Oesophageal cancer is among the ten most common types of cancer worldwide. More than 80% of the cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of oesophageal and oesophagogastric junction (OGJ) carcinomas. The Brazilian Group of Gastrointestinal Tumours invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy (including checkpoint inhibitors) and follow-up, which was followed by presentation, discussion and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of oesophageal and OGJ carcinomas in several scenarios and clinical settings.

Histologic Lymph Nodes Regression after Preoperative Chemotherapy as Prognostic Factor in Non-metastatic Advanced Gastric Adenocarcinoma

Background: The study aims to evaluate the lymph node (LN) response to preoperative chemotherapy and its impact on long-term outcomes in advanced gastric cancer (AGC). Methods: Histological specimens retrieved at gastrectomy from patients who received preoperative chemotherapy were evaluated. LN regression was graded by the adapted tumor regression grading system proposed by Becker. Patients were classified as node-negative (lnNEG) in the case of all negative LN without evidence of previous tumor involvement. Patients with LN metastasis were classified as nodal responders (lnR) in case of a regression score 1a-2 was detected in the LN. Nodal non-responders (lnNR) had a regression score of 3 in all of the metastatic nodes. Survival was compared using Kaplan-Meier and Cox regression analysis. Results: Among 87 patients included in the final analysis 29.9 % were lnNEG, 21.8 % were lnR and 48.3 % were lnNR. Kaplan-Meier curves showed a survival benefit for lnR over lnNR (p=0.03), while the survival of lnR and lnNEG patients was similar. Cox regression confirmed nodal response to be associated with decreased odds for death in univariate (HR: 0.33; 95 % CI 0.11-0.96, p=0.04) and multivariable (HR 0.37; 95 CI% 0.14-0.99, p=0.04) analysis. Conclusions: Histologic regression of LN metastasis after preoperative chemotherapy predicts the increased survival of patients with non-metastatic resectable AGC.

Lymph node response to chemoradiotherapy in oesophageal cancer patients: relationship with radiotherapy fields

BACKGROUND

The presence of lymph node metastasis (LNmets) is a poor prognostic factor in oesophageal cancer (OeC) patients treated with neoadjuvant chemoradiotherapy (nCRT) followed by surgery. Tumour regression grade (TRG) in LNmets has been suggested as a predictor for survival. The aim of this study was to investigate whether TRG in LNmets is related to their location within the radiotherapy (RT) field.

METHODS

Histopathological TRG was retrospectively classified in 2565 lymph nodes (LNs) from 117 OeC patients treated with nCRT and surgery as: (A) no tumour, no signs of regression; (B) tumour without regression; (C) viable tumour and regression; and (D) complete response. Multivariate survival analysis was used to investigate the relationship between LN location within the RT field, pathological TRG of the LN and TRG of the primary tumour.

RESULTS

In 63 (54%) patients, viable tumour cells or signs of regression were seen in 264 (10.2%) LNs which were classified as TRG-B (n = 56), C (n = 104) or D (n = 104) LNs. 73% of B, C and D LNs were located within the RT field. There was a trend towards a relationship between LN response and anatomical LN location with respect to the RT field (p = 0.052). Multivariate analysis showed that only the presence of LNmets within the RT field with TRG-B is related to poor overall survival.

CONCLUSION

Patients have the best survival if all LNmets show tumour regression, even if LNmets are located outside the RT field. Response in LNmets to nCRT is heterogeneous which warrants further studies to better understand underlying mechanisms.

Clinicopathological Significance of Pathologic Complete Lymph Node Regression After Neoadjuvant Chemoradiotherapy in Esophageal Squamous Cell Carcinoma

BACKGROUND

Pathologic complete lymph node regression (LNR), where the lymph nodes show evidence of neoadjuvant treatment effect but have no viable residual tumor cells, is sometimes observed following neoadjuvant treatments and has been shown to be prognostic; conflicting results exist in the current literature.

METHODS

Patients who received neoadjuvant chemoradiotherapy (nCRT) followed by esophagectomy for squamous carcinoma (ESCC) were retrospectively reviewed and classified according to their LNR score; 0: N(-) with no evidence of tumor involvement or regression; 1: N(-) with evidence of complete regression; 2: N(+) with < 50% viable tumor; and 3: N(+) with > 50% viable tumor.

RESULTS

In total, 136 patients, comprising 73, 25, 16, and 22 patients with LNR scores of 0, 1, 2, or 3, respectively, were included. Pathologic complete LNR (LNR 1) was significantly associated with lower risks of lymphovascular invasion (0%, p < 0.001) and perineural invasion (4%, p = 0.038), and a higher rate of pathologic complete response in the primary tumor (76%, p < 0.001). The 5-year overall survival rates were 42.1%, 52.8%, and 8.0% in patients with an LNR score of 0, 1, and 2/3, respectively (p < 0.001). There was no significant difference between patients with LNR scores of 0 and 1 in overall survival (p = 0.454), disease-free survival (p = 0.501), and cumulative incidence of recurrences (hazard ratio 0.84, 95% confidence interval 0.432-1.623, p = 0.601).

CONCLUSIONS

Pathologic complete LNR could be an indicator of nCRT sensitivity and can be regarded as a good prognostic factor in patients with ESCC. In the survival curve analysis that included patients with lymph node regression (LNR) scores of 0 (blue), 1 (red), and 2/3 (green), we found that patients with pathologic complete LNR (LNR 1), which suggests prior positive nodal involvement, had similar outcomes as those without evidence of prior tumor involvement in lymph node (LNR0).

UR, Jesus VHF, Jr WLC, Prolla G. Brazilian Group of Gastrointestinal Tumours' consensus guidelines for the management of gastric cancer

Gastric cancer is among the ten most common types of cancer worldwide. Most cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of gastric carcinomas. The Brazilian Group of Gastrointestinal Tumors (GTG) invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy and follow-up, which was followed by presentation, discussion, and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of gastric carcinomas in several scenarios and clinical settings.

Tumor Regression in Lymph Node Metastases of Esophageal Adenocarcinomas after Neoadjuvant Therapy

Tumor regression following neoadjuvant treatment can be observed in lymph node (LN) metastases similar to the primary tumor in esophageal adenocarcinomas (EAC). We evaluated the prognostic significance of tumor regression in LN metastases of locally advanced EAC of 239 patients treated with neoadjuvant radiochemotherapy (RCTX) or chemotherapy (CTX) followed by esophagectomy. We examined retrospectively the LN for histopathologic signs of regression, i.e., nodular fibrosis and acellular mucin. LN classification was performed according to two parameters: presence (−) or absence (+) of residual tumor and regression characteristics in the LN, resulting in four categories: LN−/REG−, LN−/REG+, LN+/REG+, LN+/REG−. In total, LN metastases with residual tumor were detectable in 117/239 (49%) cases. Regression in LN were observed in 85/239 cases (35.5%). The distribution of the LN/REG categories were as follows: 97 patients (40.6%) were LN−/REG−. A total of 25 patients (10.5%) were LN−/REG+. A total of 60 (25.1%) were LN+/REG+ and 57 (23.8%) LN+/REG−. The LN/Reg categorization had a significant prognostic value in univariate analysis (p < 0.001) and multivariate analysis (HR = 1.326; p = 0.002) with similar results for the subgroups of patients treated with RCTX or CTX. The prognosis of LN−/REG+ was worse than LN−/REG− but better than both LN+ categories, which was demonstrated in the Kaplan–Meier curves but did not reach statistical significance (p = 0.104 and p = 0.090, respectively). In contrast, there was no difference between LN+/REG+ and LN+/REG− (p = 0.802). In summary, regression in LN metastases of EAC can be observed in a significant number of patients after neoadjuvant therapy. Complete regression of former LN metastases in comparison to “true” negative LN seems to be of prognostic relevance but additional studies are needed to confirm this trend seen in our study.

Updates in staging and pathologic evaluation of esophageal carcinoma following neoadjuvant therapy

Esophageal carcinoma comprises two major subtypes-squamous cell carcinoma and adenocarcinoma, the incidences of which vary widely across the world and also depend on the location within the esophagus. The staging of esophageal cancer (EC) also remains unique among various gastrointestinal carcinomas, as it takes into account the location, histologic type, and grade. Its management has been evolving over the years and the recent American Joint Committee on Cancer staging system has been updated to reflect the changing practice and new data. It is clear that preoperative neoadjuvant therapy is increasingly being used for the treatment of locally advanced esophageal carcinomas, followed by surgical resection that improves survival. A variety of histologic changes can be seen after neoadjuvant therapy, which can be challenging for the pathologists. The presence of residual tumor in the surgically resected specimen and lymph node following neoadjuvant therapy is associated with poor prognosis. Hence, a thorough pathologic assessment of tumor regression grade and accurate tumor staging is required by pathologists to provide valuable prognostic information to guide further management. Tumor regression grading in ECs needs to be improved and standardized.

Significance of tumour regression in lymph node metastases of gastric and gastro-oesophageal junction adenocarcinomas

The presence of lymph node (LN) metastases is one of the most important negative prognostic factors in upper gastrointestinal carcinomas. Tumour regression similar to that in primary tumours can be observed in LN metastases after neoadjuvant therapy. We evaluated the prognostic impact of histological regression in LNs in 480 adenocarcinomas of the stomach and gastro‐oesophageal junction after neoadjuvant chemotherapy. Regressive changes in LNs (nodular and/or hyaline fibrosis, sheets of foamy histiocytes or acellular mucin) were assessed by histology. In total, regressive changes were observed in 128 of 480 patients. LNs were categorised according to the absence or presence of both residual tumour and regressive changes (LN−/+ and Reg−/+). 139 cases were LN−/Reg−, 28 cases without viable LN metastases revealed regressive changes (LN−/Reg+), 100 of 313 cases with LN metastases showed regressive changes (LN+/Reg+), and 213 of 313 metastatic LN had no signs of regression (LN+/Reg−). Overall, LN/Reg categorisation correlated with overall survival with the best prognosis for LN−/Reg− and the worst prognosis for LN+/Reg− (p < 0.001). LN−/Reg+ cases had a nearly significant better outcome than LN+/Reg+ (p = 0.054) and the latter had a significantly better prognosis than LN+/Reg− (p = 0.01). The LN/Reg categorisation was also an independent prognostic factor in multivariate analysis (HR = 1.23; 95% CI 1.1–1.38; p < 0.001). We conclude that the presence of regressive changes after neoadjuvant treatment in LNs and LN metastases of gastric and gastro‐oesophageal junction cancers is a relevant prognostic factor.

The impact of negative lymph nodes in the survival outcomes of pN+ patients following radical gastrectomy: the inverse lymph node ratio as a better score to study negative lymph nodes

The impact of negative lymph nodes (LNs) on survival of pN+ patients has been recognized. The weight of negative LNs in an inverse lymph node ratio (nR) should be related to its prognostic impact. Five hundred and two consecutive gastric cancer patients, who underwent radical gastrectomy, were included. Patients were split into groups according to the number of harvested nodes and a cross-tabulation with pTNM stages was performed to test differences in the tumor burden. pN+ patients (n = 296) were split into groups of negative LNs harvested. We tested an alternative formula for computing a lymph node ratio: nR = total number of harvested nodes/total number of positive nodes. The median number of negative LNs was significantly different (p < 0.01) between dissection groups, but not the median of positive nodes (p > 0.05). No difference in pTNM percentage distribution was found between these groups (p > 0.05). When tested, the overall survival improved significantly for groups with larger numbers of negative LNs (p < 0.001). A cutoff of nR ≥ 6 was an independent prognostic factor for survival (p = 0.001), and the survival of pN+ patients with nR ≥ 6 was not different from pN0 patients. The impact of the number of negative LNs on the survival of the pN+ patients was demonstrated. The higher numbers in the numerator of the nR was due to the disproportion between harvested negative LNs and metastatic LNs. Larger ratios imply more negative lymph nodes in relation to positive lymph nodes, which was significantly associated with survival. We believe that the proposed nR is a friendlier to use format because of its intuitive interpretation.

Varying practices in tumor regression grading of gastrointestinal carcinomas after neoadjuvant therapy: results of an international survey

Tumor regression grading is routinely performed on neoadjuvantly treated gastrointestinal cancer resections. Challenges in tumor regression grading include grossing standards, multiple grading systems, and difficulty interpreting therapy-induced changes. We surveyed gastrointestinal pathologists around the world for their practices in handling neoadjuvantly treated gastrointestinal cancer specimens and reporting tumor regression using a 23-question online survey. Topics addressed grossing, histologic work-up, tumor regression grading systems, and degree of difficulty identifying and estimating residual cancer within treatment effect. Two-hundred three responses were received, including 173 participants who completed the entire questionnaire. Fifty percent of the participants were from Europe, 29% from North America, 10% from Australia, and 11% from other continents. Ninety-five percent routinely report a tumor regression grade and 92% have standardized grossing and histologic work-up: 27% always completely embed the entire tumor bed, 54% embed the complete tumor site if not a grossly apparent, large mass. Fifty-nine percent use hematoxylin & eosin alone for assessment; the remaining use additional stains. In North America and Australia, the American Joint Committee on Cancer (AJCC)/College of American Pathologists (CAP)/Ryan system is routinely used for gastroesophageal (71%) and rectal carcinomas (77%). In Europe, the Mandard system is common (36%) for gastroesophageal tumors, followed by AJCC/CAP/Ryan (22%), and Becker (10%); for rectal CA, the Dworak system (30%) is followed by AJCC/CAP/Ryan (24%) and Mandard (14%). This regional differences were significant (p < 0.001 each). Fifty-one percent prefer a four-tiered system. Sixty-six percent think that regressive changes in lymph nodes should be part of a regression grade. Sixty-nine percent consider identifying residual tumor straight-forward, but estimating therapy-induced fibrosis difficult (57%). Free comments raised issues of costs for work-up and clinical relevance. In conclusion, this multinational survey provides a comprehensive overview of grossing and histologic work-up with regards to tumor regression grading in gastrointestinal cancers with partly significant regional differences particularly between North America and Europe.

Relevant issues in tumor regression grading of histopathological response to neoadjuvant treatment in adenocarcinomas of the esophagus and gastroesophageal junction

Multimodality treatment combining surgery and oncologic treatment has become widely applied in curative treatment of esophageal and gastroesophageal junction adenocarcinoma. There is a need for a standardized tumor regression grade scoring system for clinically relevant effects of neoadjuvant treatment effects. There are numerous tumor regression grading systems in use and there is no international standardization. This review has found nine different international systems currently in use. These systems all differ in detail, which inhibits valid comparisons of results between studies. Tumor regression grading in esophageal and gastroesophageal junction adenocarcinoma needs to be improved and standardized. To achieve this goal, we have invited a significant group of international esophageal and gastroesophageal junction adenocarcinoma pathology experts to perform a structured review in the form of a Delphi process. The aims of the Delphi include specifying the details for the disposal of the surgical specimen and defining the details of, and the reporting from, the agreed histological tumor regression grade system including resected lymph nodes. The second step will be to perform a validation study of the agreed tumor regression grading system to ensure a scientifically robust inter- and intra-observer variability and to incorporate the consented tumor regression grading system in clinical studies to assess its predictive and prognostic role in treatment of esophageal and gastroesophageal junction adenocarcinomas. The ultimate aim of the project is to improve survival in esophageal and gastroesophageal adenocarcinoma by increasing the quality of tumor regression grading, which is a key component in treatment evaluation and future studies of individualized treatment of esophageal cancer.

Consensus on the pathological definition and classification of poorly cohesive gastric carcinoma

BACKGROUND AND AIMS

Clinicopathological characteristics of gastric cancer (GC) are changing, especially in the West with a decreasing incidence of distal, intestinal-type tumours and the corresponding increasing proportion of tumours with Laurén diffuse or WHO poorly cohesive (PC) including signet ring cell (SRC) histology. To accurately assess the behaviour and the prognosis of these GC subtypes, the standardization of pathological definitions is needed.

METHODS

A multidisciplinary expert team belonging to the European Chapter of International Gastric Cancer Association (IGCA) identified 11 topics on pathological classifications used for PC and SRC GC. The topics were debated during a dedicated Workshop held in Verona in March 2017. Then, through a Delphi method, consensus statements for each topic were elaborated.

RESULTS

A consensus was reached on the need to classify gastric carcinoma according to the most recent edition of the WHO classification which is currently WHO 2010. Moreover, to standardize the definition of SRC carcinomas, the proposal that only WHO PC carcinomas with more than 90% poorly cohesive cells having signet ring cell morphology have to be classified as SRC carcinomas was made. All other PC non-SRC types have to be further subdivided into PC carcinomas with SRC component (< 90% but > 10% SRCs) and PC carcinomas not otherwise specified (< 10% SRCs).

CONCLUSION

The reported statements clarify some debated topics on pathological classifications used for PC and SRC GC. As such, this consensus classification would allow the generation of evidence on biological and prognostic differences between these GC subtypes.

Lymph node regression and survival following neoadjuvant chemotherapy in oesophageal adenocarcinoma

BACKGROUND

The aim was to define the pathological response in lymph nodes following neoadjuvant chemotherapy for oesophageal adenocarcinoma and to quantify any associated survival benefit.

METHODS

Lymph nodes retrieved at oesophagectomy were examined retrospectively by two pathologists for evidence of a response to chemotherapy. Patients were classified as lymph node-negative (either negative nodes with no evidence of previous tumour involvement or negative with evidence of complete regression) or positive (allocated a lymph node regression score based on the proportion of fibrosis to residual tumour). Lymph node responders (score 1, complete response; 2, less than 10 per cent remaining tumour; 3, 10-50 per cent remaining tumour) and non-responders (score 4, more than 50 per cent viable tumour; 5, no response) were compared in survival analyses using Kaplan-Meier and Cox regression analysis.

RESULTS

Among 377 patients, 256 had neoadjuvant chemotherapy. Overall, 68 of 256 patients (26·6 per cent) had a lymph node response and 115 (44·9 per cent) did not. The remaining 73 patients (28·5 per cent) had negative lymph nodes with no evidence of regression. Some patients had a lymph node response in the absence of a response in the primary tumour (27 of 99, 27 per cent). Lymph node responders had a significant survival benefit (P < 0·001), even when stratified by patients with or without a response in the primary tumour. On multivariable analysis, lymph node responders had decreased overall (hazard ratio 0·53, 95 per cent c.i. 0·36 to 0·78) and disease-specific (HR 0·42, 0·27 to 0·66) mortality, and experienced reduced local and systemic recurrence.

CONCLUSION

Lymph node regression is a strong prognostic factor and may be more important than response in the primary tumour.

Prognostic value of pathological lymph node status and primary tumour regression grading following neoadjuvant chemotherapy - results from the MRC OE02 oesophageal cancer trial

AIMS

Neoadjuvant chemotherapy (NAC) remains an important therapeutic option for advanced oesophageal cancer (OC). Pathological tumour regression grade (TRG) may offer additional information by directing adjuvant treatment and/or follow-up but its clinical value remains unclear. We analysed the prognostic value of TRG and associated pathological factors in OC patients enrolled in the Medical Research Council (MRC) OE02 trial.

METHODS AND RESULTS

Histopathology was reviewed in 497 resections from OE02 trial participants randomised to surgery (S group; n = 244) or NAC followed by surgery [chemotherapy plus surgery (CS) group; n = 253]. The association between TRG groups [responders (TRG1-3) versus non-responders (TRG4-5)], pathological lymph node (LN) status and overall survival (OS) was analysed. One hundred and ninety-five of 253 (77%) CS patients were classified as 'non-responders', with a significantly higher mortality risk compared to responders [hazard ratio (HR) = 1.53, 95% confidence interval (CI) = 1.05-2.24, P = 0.026]. OS was significantly better in patients without LN metastases irrespective of TRG [non-responders HR = 1.87, 95% CI = 1.33-2.63, P < 0.001 versus responders HR = 2.21, 95% CI = 1.11-4.10, P = 0.024]. In multivariate analyses, LN status was the only independent factor predictive of OS in CS patients (HR = 1.93, 95% CI = 1.42-2.62, P < 0.001). Exploratory subgroup analyses excluding radiotherapy-exposed patients (n = 48) showed similar prognostic outcomes.

CONCLUSION

Lymph node status post-NAC is the most important prognostic factor in patients with resectable oesophageal cancer, irrespective of TRG. Potential clinical implications, e.g. adjuvant treatment or intensified follow-up, reinforce the importance of LN dissection for staging and prognostication.

Tumor regression grading of gastrointestinal cancers after neoadjuvant therapy

Neoadjuvant therapy has been successfully introduced in the treatment of locally advanced gastrointestinal malignancies, particularly esophageal, gastric, and rectal cancers. The effects of preoperative chemo- or radiochemotherapy can be determined by histopathological investigation of the resection specimen following this treatment. Frequent histological findings after neoadjuvant therapy include various amounts of residual tumor, inflammation, resorptive changes with infiltrates of foamy histiocytes, foreign body reactions, and scarry fibrosis. Several tumor regression grading (TRG) systems, which aim to categorize the amount of regressive changes after cytotoxic treatment in primary tumor sites, have been proposed for gastroesophageal and rectal carcinomas. These systems primarily refer to the amount of therapy-induced fibrosis in relation to the residual tumor (e.g., the Mandard, Dworak, or AJCC systems) or the estimated percentage of residual tumor in relation to the previous tumor site (e.g., the Becker, Rödel, or Rectal Cancer Regression Grading systems). TRGs provide valuable prognostic information, as in most cases, complete or subtotal tumor regression after neoadjuvant treatment is associated with better patient outcomes. This review describes the typical histopathological findings after neoadjuvant treatment, discusses the most commonly used TRG systems for gastroesophageal and rectal carcinomas, addresses the limitations and critical issues of tumor regression grading in these tumors, and describes the clinical impact of TRG.