Recommendations for neoadjuvant pathologic staging (ypTNM) of cancer of the esophagus and esophagogastric junction for the 8th edition AJCC/UICC staging manuals

Is the new distribution of early esophageal adenocarcinoma stages improving the prognostic prediction of the 8th edition of the TNM staging system for esophageal cancer?

Background

The 8^th edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) staging system released in 2017 reclassified the pTNM stage of early esophageal adenocarcinoma from stage IA in the 7^th edition to stage IA and IB and from stage IB in the 7^th edition to stage IC. In this study, we analyzed the reliability of the new staging system through clinical data analysis.

Methods

We selected patient data from the Surveillance, Epidemiology, and End Results (SEER) database. From 2004 to 2014, data for a total of 714 patients were included in the study and were divided into groups representing stage IA (n=84), IB (n=386) and IC (n=244) according to the 8^th edition.

Results

In the 8^th edition, there was no significant difference between groups IA and IB in overall survival (OS) (P=0.331) or esophageal cancer-specific survival (ECSS) (P=0.341). However, the long-term survival rates of groups IA and IB were significantly higher than those of group IC. Cox regression analysis indicated that the use of new staging system does not affect prognosis. We also attempted to stratify the tumors by T stage and histological grade but found no significant difference.

Conclusions

We used the SEER database to compare the staging of early esophageal adenocarcinomas between the 8^th and 7^th editions of the AJCC/UICC TNM staging system. Based on our data, the 8^th edition is not superior to the 7^th edition.

Clinical implication of the innovations of the 8th edition of the TNM classification for esophageal and esophago-gastric cancer

Epidemiology of esophageal cancer and esophagogastric junction (EGJ) has deeply changed for the past two decades with a dramatically increase of adenocarcinoma whereas squamous cell carcinoma (SCC) has slowly decreased. Moreover, the two histological types differ in a number of features including risks factors, tumor location, tumor biology and outcomes. In acknowledgement of these differences, the newest 8^th edition of the American Joint Committee on Cancer (AJCC) tumor, node and metastasis (TNM) staging classification of epithelial cancers of the esophagus and EGJ has refined this histology-specific disease stage with incorporation of new anatomic and non-anatomic categories. Based on data-driven of patients collected through the Worldwide Esophageal Cancer Collaboration (WECC) group, the 8^th edition database encompasses a six-continent cohort of 22,654 patients among 33 institutions including patients treated with surgery alone and, for the first time, patients treated after neoadjuvant treatment. Anatomic categories include T descriptors (tumor invasion), N descriptors (regional lymph node invasion) and M descriptors (distant site). Non anatomic categories include grade differentiation (G descriptors) and tumor location (L descriptors). Category descriptors are currently assessed by endoscopy with biopsy, by endoscopy ultrasound fine-needle aspiration (EUS-FNA), by thoracic-abdominal-pelvic computed tomography (CT) and whole body flurodeoxyglucose positron emission tomography (FDG-PET) fused with CT. The new 8^th edition considers separate and temporally related cancer classification based on the treatment strategy: clinical cTNM (before any treatment), pathologic pTNM (after surgery alone) and postneoadjuvant pathologic ypTNM (after neoadjuvant treatment followed by surgery). The 8th edition permits a more robust and reliable random forest-based machine learning analysis. Refinement of each T, N, M categories and subcategories makes the 8^th edition more accurate and more adaptable to the current practice including neoadjuvant regimen. The main objective of this review is to examine the current staging of esophageal cancer and the new aspects of the 8^th edition with its applications to clinical practice.

Prognostic differences in 8th edition TNM staging of esophagogastric adenocarcinoma after neoadjuvant treatment

BACKGROUND

Prognostic differences between pTN- and ypTN-categories and the prognostic accuracy of the 8th edition UICC-pTNM- and AJCC-ypTNM-staging-system for esophageal and gastric adenocarcinoma are unclear.

METHODS

We retrospectively analyzed data of 740 patients with esophagogastric adenocarcinoma, who underwent curative surgery (344 after neoadjuvant treatment [NT]) at our institution. Survival analyses were performed according to Kaplan-Meier (log-rank test). Multivariate analyses were performed using the Cox proportional hazard model.

RESULTS

Low ypT-categories did not discriminate overall survival (ypT0: reference; ypT1: HR1.0/p = 0.909; ypT2: HR0.9/p = 0.845; ypT3: HR1.5/p = 0.184; ypT4: HR2.8/p = 0.004) and no difference was found between ypN1- and ypN2-disease (ypN0: HR0.4/p < 0.001; ypN1: reference; ypN2: HR1.1/p = 0.653; ypN3: HR1.7/p = 0.014). In esophageal adenocarcinoma the UICC-TNM- and AJCC-ypTNM-staging-system was able to predict survival for patients after NT, while in gastric cancer it failed to provide sufficient prognostic information. A simplified staging system provided better stratification after NT and was an independent prognosticator for both esophageal and gastric adenocarcinoma (stage I: reference; stage II: HR2.2/p = 0.005; stage III: HR4.1/p < 0.001).

CONCLUSION

Prognostic value of ypTN-categories seems limited. After NT the current UICC/AJCC-staging-system is able to predict survival in esophageal adenocarcinoma, but needs to be reevaluated in gastric cancer patients and modified if needed. A novel simplified staging system might be more practicable for patients after NT.

The ypT category does not impact overall survival in node negative gastric cancer

BACKGROUND

Although the eighth-edition American Joint Committee on Cancer (AJCC) gastric cancer staging system created ypTNM staging for patients who underwent preoperative therapy, the ideal ypTNM grouping is unknown. We sought to investigate risk factors for OS in ypT0-3N0M0 gastric cancer.

METHODS

From an institutional database of The University of Texas MD Anderson Cancer Center and the National Cancer Database (NCDB), we identified patients with ypT0-3N0M0 gastric adenocarcinoma who underwent R0 gastrectomy after chemotherapy or chemoradiation during 1995-2015 (MD Anderson) or 2006-2014 (NCDB).

RESULTS

The study included 175 MD Anderson and 3200 NCDB patients. By multivariable analysis, ypT category was not associated with OS (hazard ratio [HR] for ypT3 vs ypT1: MD Anderson, 0.83 [95% CI, 0.36-1.92], P = 0.669; NCDB, 0.96 [95% CI, 0.85-1.08], P = 0.472). cN-positive disease was not associated with OS in the MD Anderson cohort (HR, 0.96 [95% CI, 0.55-1.67]; P = 0.873) but was weakly associated with shorter OS in the NCDB cohort (HR, 1.11 [95% CI, 1.01-1.21]; P = 0.031).

CONCLUSIONS

The ypT category does not impact OS in ypT0-3N0M0 gastric cancer. The impact of cN status on OS appeared limited. These findings should be considered in future systems of post-neoadjuvant pathologic staging.

ypT0N+: the unusual patient with pathological complete tumor response but with residual lymph node disease after neoadjuvant chemoradiation for esophageal cancer, what's up?

Background

Little is known about the prognostic significance of residual nodal disease in otherwise complete pathologic responders (ypT0N+) after neoadjuvant chemoradiation (nCRT) for esophageal cancer (EC). The purpose is to analyze the long-term outcomes of EC patients with ypT0N+ following nCRT and esophagectomy.

Methods

From a single institution database, 466 consecutive EC patients undergoing esophagectomy after nCRT were collected (1996-2016). ypT0N+ responders were compared to pathological complete responders (ypT0N0) and to pathological non-complete responders (ypT+N0 and ypT+N+).

Results

There were 149 ypT0N0, 31 ypT0N+, 141 ypT+N0 and 145 ypT+N+. Median overall survival (OS) was worse in ypT0N+ (21.7 months) and ypT+N+ (16.8 months) compared to ypT0N0 (55.2 months) and ypT+N0 (42.0 months). Stratification by histology revealed a significant difference in prevalence of ypT0: 62.5% in 184 squamous cell carcinomas (SCC) compared to 23.0% in 282 adenocarcinomas (ADC) (P<0.0001) but not in ypT0N+ (15% vs. 22% respectively, P=0.25). In ADC, locoregional recurrence in ypT0N+ (43%) was comparable to ypT+N+ (31%) and more common compared to ypT0N0 (7%) and ypT+N0 (10%), reflected in median OS rates of 20.6, 17.5, 53.0 and 36.6 months respectively. Median OS in ADC is significantly determined by number of positive lymph nodes, being 21.7 months for pN1 and 2.7 months for pN2/3 (P=0.005) in ypT0N+ and 33.7 months for pN1 and 16.2 months for pN2/3 (P=0.031) in ypT+N+. In SCC, locoregional recurrences were found in 17% of ypT0N+, 33% of ypT+N+, 11% of ypT0N0 and 22% in ypT+N0 and median OS was 26.6, 15.6, 55.2 and 43.8 months respectively. In SCC ypN+ number of affected lymph nodes showed no difference on OS.

Conclusions

ypT0N+ in EC patients following nCRT has a poor prognosis and behaves similar to ypT+N+. However, stratification by histology shows that this is especially true in ADC but seems determined by the number of involved lymph nodes.

Impact of postoperative TNM stages after neoadjuvant therapy on prognosis of adenocarcinoma of the gastro-oesophageal junction tumours

AIM

To compare prognostic relevance of postoperative tumour/node/metastasis (TMN) stages between patients with and without neoadjuvant treatment.

METHODS

Data from patients with adenocarcinoma of the gastro-oesophageal junction (AEG) who had undergone surgical resection at a single German university centre were retrospectively analysed. Patients with or without neoadjuvant preoperative treatment were selected by exact matching based on preoperative staging. Standard assessment of preoperative (c)TNM stage was based on endoscopic ultrasound and computed tomography of the thorax and abdomen, according to the American Joint Committee on Cancer/Union for International Cancer Control classification system. Patients with cT1cN0cM0 and cT2cN0cM0 stages were excluded from the study, as these patients are generally not recommended for pretreatment. Long-term survival among the various postoperative TNM stages was compared between the groups of patients with or without neoadjuvant treatment. For statistical assessments, a P-value of ≤ 0.05 was considered significant.

RESULTS

The study included a total of 174 patients. The group of patients who had received preoperative neoadjuvant treatment included more cases of AEG (Siewert) type 1 carcinoma (P < 0.001), and consequently oesophagectomy was performed more frequently among these patients (P < 0.001). The two groups (with or without preoperative neoadjuvant treatment) had comparable preoperative T stages, but the group of patients with preoperative neoadjuvant treatment presented a higher rate of preoperative N-positive disease (P = 0.020). Overall long-term survival was not different between the two groups of patients according to tumours of different AEG classifications, receipt of oesophagectomy or gastrectomy, nor between patients with similar postoperative TNM stage, resection margin and grading. However, an improvement of long-term survival was found for patients with nodal down-staging after neoadjuvant therapy (P = 0.053).

CONCLUSION

The prognostic relevance of postoperative TNM stages is similar for AEG in patients with or without neoadjuvant preoperative treatment, but treatment-related nodal down-staging prognosticates longer-term survival.

Application of the Eighth AJCC TNM Staging System in Patients With Esophageal Squamous Cell Carcinoma

BACKGROUND

The eighth edition of the American Joint Committee on Cancer Tumor-Node-Metastasis staging system separates classifications for the clinical (c), pathologic (p), and postneoadjuvant pathologic (yp) stages. We aimed to evaluate its application in patients with esophageal squamous cell carcinoma (ESCC).

METHODS

Patient data were obtained from the Taiwan Cancer Registry database. Patients who underwent esophagectomy for c stage I to III ESCC were included for survival analysis.

RESULTS

Data of 3,399, 1,805, and 1,594 patients were included for c, p, and yp staging, respectively. The 3-year overall survival (OS) rates for c stage I, II, and III were 67.4%, 46.7%, and 38.4%, respectively. The 3-year OS rates for p stage I, II, III, and IV were 70.7%, 49.8%, 30.8%, and 10.6%, respectively. The 3-year OS rates for yp stage I, II, III, and IV were 59.4%, 37.8%, 27.6%, and 3.7%, respectively. Survival curve analysis demonstrated a robust discriminatory capability and monotonicity of gradients of the new system. However, yp stage I was observed in a heterogeneous group of patients with substantial survival differences. Meanwhile, patients in the ypT0 N0 stage had a 5-year OS rate of 52.1%, which was equivalent to that of patients with p stage I (54.5%). The 5-year OS rate of patients in the ypTis-2N0 was 39.1%, which was equivalent to that of patients in p stage II (40.1%).

CONCLUSIONS

The present study serves as an external validation of the newly released staging system in the prognostication of patients with ESCC and suggests subgrouping of the yp stage I into ypT0 N0 and non-ypT0 N0 in the future.

Eighth Edition Staging of Thoracic Malignancies: Implications for the Reporting Pathologist

Context The Staging and Prognostic Factors Committee of the International Association for the Study of Lung Cancer, in conjunction with the International Mesothelioma Interest Group, the International Thymic Malignancy Interest Group, and the Worldwide Esophageal Cancer Collaboration, developed proposals for the 8th edition of their respective tumor, node, metastasis (TNM) staging classification systems. Objective To review these changes and discuss issues for the reporting pathologist. Data Sources Proposals were based on international databases of lung (N = 94 708), with an external validation using the US National Cancer Database; mesothelioma (N = 3519); thymic epithelial tumors (10 808); and epithelial cancers of the esophagus and esophagogastric junction (N = 22 654). Conclusions These proposals have been mostly accepted by the Union for International Cancer Control and the American Joint Committee on Cancer and incorporated into their respective staging manuals (2017). The Union for International Cancer Control recommended implementation beginning in January 2017; however, the American Joint Committee on Cancer has deferred deployment of the eighth TNM until January 1, 2018, to ensure appropriate infrastructure for data collection. This manuscript summarizes the updated staging of thoracic malignancies, specifically highlighting changes from the 7th edition that are relevant to pathologic staging. Histopathologists should become familiar with, and start to incorporate, the 8th edition staging in their daily reporting of thoracic cancers henceforth.

Neoadjuvant chemoradiotherapy followed by minimally invasive esophagectomy: is it a superior approach for locally advanced resectable esophageal squamous cell carcinoma?

Background

Few studies reported the outcomes of minimally invasive esophagectomy (MIE) in treating patients with esophageal squamous cell carcinoma (ESCC) after neoadjuvant chemoradiotherapy (nCRT). The aim of the study was to investigate the feasibility and efficacy of nCRT plus MIE (RM) strategy in treating locally advanced resectable ESCC.

Methods

This retrospective study included 175 patients with ESCC undergoing surgical resection after neoadjuvant therapy in our institution from 2010 to 2016. Patients were stratified into three groups: RM, [neoadjuvant chemotherapy (nCT) plus MIE] (CM) and [nCT plus open esophagectomy (OE)] (CO).

Results

Seventy-six (43.4%), 42 (24%) and 57 (32.6%) patients received RM, CM and CO approach, respectively. Compared with CO approach, RM or CM approach had shorter operation duration (188±39, 185±37 vs. 209±45 minutes, P=0.004, P=0.009) and less blood loss (124±88, 122±79 vs. 166±92 mL, P=0.001, P=0.003). There was a trend with lower risk of postoperative non-surgical complications in RM and CM approach [odds ratio (OR) 0.45, 0.200-1.040; P=0.062; OR 0.41, 0.150-1.160; P=0.093]. There were no differences in 30- and 90-day mortality among all groups. RM approach was more likely to achieve pathological complete regression (27.6% vs. 4.8%, 1.8%, P=0.001, P=0.001) and fewer lymph node metastasis (25.0% vs. 57.1%, 61.4%, P=0.001, P=0.001) than CM or CO approach. Survival analysis revealed a potential trend towards improved overall survival in RM approach compared with CM or CO approach (P=0.098, P=0.166).

Conclusions

RM approach was a safe and efficient strategy in treating locally advanced resectable ESCC.

Validation of the eighth clinical American Joint Committee on Cancer stage grouping for esophageal cancer

AIM

To validate the American Joint Committee on Cancer (AJCC) clinical staging system for esophageal cancer using Surveillance, Epidemiology and End Results database.

METHODS

Cancer-specific survival analyses for clinically-staged patients with esophageal cancer according to both seventh and eighth editions were conducted through Kaplan-Meier analysis.

RESULTS

For cancer-specific survival according to both seventh and eighth clinical systems, p-values for pairwise comparisons were nonsignificant in many comparisons. C-index for adenocarcinoma was: 0.671 according to the seventh AJCC and 0.671 according to the clinical eighth AJCC. C-index for squamous cell carcinoma according to the seventh AJCC was: 0.634 and 0.643 according to clinical eighth AJCC.

CONCLUSION

Minimal improvement was achieved by the eighth clinical AJCC staging system for esophageal cancer.

Scientific Advances in Thoracic Oncology 2016

Lung cancer care is rapidly changing with advances in genomic testing, the development of next-generation targeted kinase inhibitors, and the continued broad study of immunotherapy in new settings and potential combinations. The International Association for the Study of Lung Cancer and the Journal of Thoracic Oncology publish this annual update to help readers keep pace with these important developments. Experts in thoracic cancer and care provide focused updates across multiple areas, including prevention and early detection, molecular diagnostics, pathology and staging, surgery, adjuvant therapy, radiotherapy, molecular targeted therapy, and immunotherapy for NSCLC, SCLC, and mesothelioma. Quality and value of care and perspectives on the future of lung cancer research and treatment have also been included in this concise review.

Cancer of the esophagus and esophagogastric junction-Major changes in the American Joint Committee on Cancer eighth edition cancer staging manual

Answer questions and earn CME/CNE New to the eighth edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual for epithelial cancers of the esophagus and esophagogastric junction are separate, temporally related cancer classifications: 1) before treatment decision (clinical); 2) after esophagectomy alone (pathologic); and 3) after preresection therapy followed by esophagectomy (postneoadjuvant pathologic). The addition of clinical and postneoadjuvant pathologic stage groupings was driven by a lack of correspondence of survival, and thus prognosis, between both clinical and postneoadjuvant pathologic cancer categories (facts about the cancer) and pathologic categories. This was revealed by a machine-learning analysis of 6-continent data from the Worldwide Esophageal Cancer Collaboration, with consensus of the AJCC Upper GI Expert Panel. Survival is markedly affected by histopathologic cell type (squamous cell carcinoma and adenocarcinoma) in clinically and pathologically staged patients, requiring separate stage grouping for each cell type. However, postneoadjuvant pathologic stage groups are identical. For the future, more refined and granular data are needed. This requires: 1) more accurate clinical staging; 2) innovative solutions to pathologic staging challenges in endoscopically resected cancers; 3) integration of genomics into staging; and 4) precision cancer care with targeted therapy. It is the responsibility of the oncology team to accurately determine and record registry data, which requires eliminating both common errors and those related to incompleteness and inconsistency. Despite the new complexity of eighth edition staging of cancers of the esophagus and esophagogastric junction, these key concepts and new directions will facilitate precision cancer care. CA Cancer J Clin 2017;67:304-317. © 2017 American Cancer Society.

8th edition AJCC/UICC staging of cancers of the esophagus and esophagogastric junction: application to clinical practice

The 8th edition of the American Joint Committee on Cancer (AJCC) staging of epithelial cancers of the esophagus and esophagogastric junction (EGJ) presents separate classifications for clinical (cTNM), pathologic (pTNM), and postneoadjuvant (ypTNM) stage groups. Histopathologic cell type markedly affects survival of clinically and pathologically staged patients, requiring separate groupings for each cell type, but ypTNM groupings are identical for both cell types. Clinical categories, typically obtained by imaging with minimal histologic information, are limited by resolution of each method. Strengths and shortcomings of clinical staging methods should be recognized. Complementary cytology or histopathology findings may augment imaging and aid initial treatment decision-making. However, prognostication using clinical stage groups remains coarse and inaccurate compared with pTNM. Pathologic staging is losing its relevance for advanced-stage cancer as neoadjuvant therapy replaces esophagectomy alone. However, it remains relevant for early-stage cancers and as a staging and survival reference point. Although pathologic stage could facilitate decision-making, its use to direct postoperative adjuvant therapy awaits more effective treatment. Prognostication using pathologic stage groups is the most refined of all classifications. Postneoadjuvant staging (ypTNM) is introduced by the AJCC but not adopted by the Union for International Cancer Control (UICC). Drivers of this addition include absence of equivalent pathologic (pTNM) categories for categories peculiar to the postneoadjuvant state (ypT0N0-3M0 and ypTisN0-3M0), dissimilar stage group compositions, and markedly different survival profiles. Thus, prognostication is specific for patients undergoing neoadjuvant therapy. The role of ypTNM classification in additional treatment decision-making is currently limited. Precision cancer care advances are necessary for this information to be clinically useful.

Recommendations for clinical staging (cTNM) of cancer of the esophagus and esophagogastric junction for the 8th edition AJCC/UICC staging manuals

We report analytic and consensus processes that produced recommendations for clinical stage groups (cTNM) of esophageal and esophagogastric junction cancer for the AJCC/UICC cancer staging manuals, 8th edition. The Worldwide Esophageal Cancer Collaboration (WECC) provided data on 22,123 clinically staged patients with epithelial esophageal cancers. Risk-adjusted survival for each patient was developed using random survival forest analysis from which (1) data-driven clinical stage groups were identified wherein survival decreased monotonically and was distinctive between and homogeneous within groups and (2) data-driven anatomic clinical stage groups based only on cTNM. The AJCC Upper GI Task Force, by smoothing, simplifying, expanding, and assessing clinical applicability, produced (3) consensus clinical stage groups. Compared with pTNM, cTNM survival was "pinched," with poorer survival for early cStage groups and better survival for advanced ones. Histologic grade was distinctive for data-driven grouping of cT2N0M0 squamous cell carcinoma (SCC) and cT1-2N0M0 adenocarcinoma, but consensus removed it. Grouping was different by histopathologic cell type. For SCC, cN0-1 was distinctive for cT3 but not cT1-2, and consensus removed cT4 subclassification and added subgroups 0, IVA, and IVB. For adenocarcinoma, N0-1 was distinctive for cT1-2 but not cT3-4a, cStage II subgrouping was necessary (T1N1M0 [IIA] and T2N0M0 [IIB]), advanced cancers cT3-4aN0-1M0 plus cT2N1M0 comprised cStage III, and consensus added subgroups 0, IVA, and IVB. Treatment decisions require accurate cStage, which differs from pStage. Understaging and overstaging are problematic, and additional factors, such as grade, may facilitate treatment decisions and prognostication until clinical staging techniques are uniformly applied and improved.

Cancer of the Esophagus and Esophagogastric Junction: An Eighth Edition Staging Primer

This primer for eighth edition staging of esophageal and esophagogastric epithelial cancers presents separate classifications for the clinical (cTNM), pathologic (pTNM), and postneoadjuvant pathologic (ypTNM) stage groups, which are no longer shared. For pTNM, pT1 has been subcategorized as pT1a and pT1b for the subgrouping pStage I adenocarcinoma and squamous cell carcinoma. A new, simplified esophagus-specific regional lymph node map has been introduced. Undifferentiated histologic grade (G4) has been eliminated; additional analysis is required to expose histopathologic cell type. Location has been removed as a category for pT2N0M0 squamous cell cancer. The definition of the esophagogastric junction has been revised. ypTNM stage groups are identical for both histopathologic cell types, unlike those for cTNM and pTNM.