ypN0: Does It Matter How You Get There? Nodal Downstaging in Esophageal Cancer

Benefits of neoadjuvant chemotherapy: is the prognosis of ypN0 patients after neoadjuvant chemotherapy comparable to that of pN0 patients undergoing surgery alone?

BACKGROUND

Preoperative treatment has become widely recognized for improving survival in patients with esophageal cancer. The present study aimed to compare the prognosis between patients with pathological node-negative status treated with surgery alone (SA-pN0) and those who were clinically node-positive but converted to ypN0 following neoadjuvant chemotherapy (NAC-ypN0) in cases of advanced thoracic esophageal squamous cell carcinoma (ESCC).

METHODS

This retrospective analysis used a multicenter database of 4849 consecutive patients who underwent treatment for esophageal cancer. Patients with clinical T2 or more advanced ESCC who underwent standard subtotal esophagectomy between 1990 and 2017 were included. The NAC-ypN0 group was compared with the SA-pN0 group in terms of patient characteristics, recurrence patterns, and survival outcomes using propensity score-matched analysis.

RESULTS

In total, 109 patients were classified as NAC-ypN0 and 137 as SA-pN0. Propensity score matching resulted in the selection of 87 patients per group. Compared with the SA-pN0 group, the NAC-ypN0 group had a significantly more advanced clinical TNM stage and underwent significantly more three-field lymphadenectomies. Pathological findings showed downstaging of the pT stage in the NAC-ypN0 group, resulting in an equivalent distribution between the two groups. Additionally, the NAC-ypN0 group had significantly lower rates of lymphatic invasion (33% vs. 56%) and venous invasion (21% vs. 52%). Recurrence rates (21% vs. 22%) and survival outcomes (5-year overall survival: 83.9% vs. 76.1%, P = 0.110) were comparable between the two groups.

CONCLUSIONS

The NAC-ypN0 group demonstrated reduced lymphovascular invasion and showed a prognosis comparable to that of the SA-pN0 group.

Positive Lymph Node Status Before and After Neoadjuvant Chemoradiotherapy Improves Prediction of Disease-Free Survival in Esophageal Squamous Cell Carcinoma Patients

BACKGROUND

This study proposes a modified lymph node (LN) staging category (BALN) on the basis of the number of positive LNs before (prepN) and after (ypN) neoadjuvant chemoradiotherapy (nCRT) to improve prognostic stratification in esophageal squamous cell carcinoma (ESCC).

PATIENTS AND METHODS

A total of 381 patients with ESCC who underwent nCRT at three medical centers were retrospectively enrolled. The ypN categories were scored according to the eighth edition of the American Joint Committee of Cancer (AJCC) staging manual. LNs with regression changes or vital tumor cells were used for interpretation of the prepN stage, reflecting the estimated number of originally involved LNs. BALN category was organized on the basis of the sum of the number of positive LNs in prepN and ypN categories.

RESULTS

BALN category revealed clearer survival classification and prognostic value of disease-free survival (DFS) in patients with ESCC (p < 0.0001). Multivariate cox proportional risk model identified BALN stage as a significant risk factor of DFS of patients with ESCC (p < 0.001). The results of 5-year time-area under the curve (AUC) demonstrated better predictive ability of the BALN category than the ypN category (AUC 0.755 versus 0.707, p = 0.004). The rypTNM system based on BALN category exhibited comparable survival discrimination and better predictive performance than ypTNM system (AUC 0.799 versus 0.756, p = 0.020).

CONCLUSIONS

The BALN stage and the revised ypTNM system showed preferable prognosis outcomes to the ypN stage and the ypTNM system, respectively. Evaluating LN status before and after nCRT could allow for more accurate esophageal cancer staging.

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.

Lymph node regression after neoadjuvant chemoradiotherapy in rectal cancer

AIMS

Lymph node metastases (LNM) are one of the most important prognostic indicators in solid tumours and a major component of cancer staging. Neoadjuvant therapy might influence nodal status by induction of regression. Our aim is to determine the prevalence and role of regression of LNM on outcomes in patients with rectal cancer.

METHODS AND RESULTS

Four independent study populations of rectal cancer patients treated with similar regimens of chemoradiotherapy were pooled together to obtain a total cohort of 469 patients. Post-treatment nodal status (ypN) and signs of tumour regression (Reg) were incorporated to form three-tiered (ypN- Reg+, ypN- Reg- and ypN+) and four-tiered (ypN- Reg+, ypN- Reg-, ypN+ Reg+ and ypN+ Reg-) classifications. In our cohort, 31% of patients presented with ypN+ rectal cancer. As expected, we found significantly worse overall survival (OS) in ypN+ patients compared to ypN- patients (P = 0.002). The percentage of ypN- patients with lymph nodes with complete regression was 20% in our cohort. While node-negative patients with and without regression had similar OS (P = 0.09), disease-free survival (DFS) was significantly better in node-negative patients with regression (P = 0.009).

CONCLUSIONS

Regression in lymph nodes is frequent, and node-negative patients with evidence of lymph node regression have better DFS compared to node-negative patients without such evidence.

Neoadjuvant PD-1 Plus Chemotherapy for Locally Advanced Esophageal Squamous Cell Carcinoma

BACKGROUND

Clinical studies have shown that programmed cell death-1 (PD-1) inhibitors can activate T cells and inhibit cancer growth. Therefore, the use of a PD-1 inhibitor plus chemotherapy as neoadjuvant chemotherapy for locally advanced esophageal cancer is worth further exploration.

METHODS

Patients with locally advanced esophageal squamous cell carcinoma were enrolled in this study to receive two cycles of a preoperative combination of toripalimab, paclitaxel, and cisplatin. Efficacy was evaluated after two treatment cycles. The patients' postoperative pathological staging was analyzed and compared. Surgery was performed within 42 days of the start date of the last chemotherapy cycle.

RESULTS

Neoadjuvant immunochemotherapy achieved a high pathologic complete response (pCR) rate (29.0%), major pathological response rate (41.9%), and objective response rate (80.6%) and demonstrated statistically significant downstaging after neoadjuvant therapy (P < .05) with manageable treatment-related adverse effects. No significant association was found between PD-L1 level and pCR (P = .365). In addition, R0 resection was achieved in all 31 (100%) patients during surgery. For all the included patients, the one-year progression-free survival rate was 87.1% (95% CI: 75.3%-98.9%), the one-year overall survival (OS) rate was 96.8% (95% CI: 79.8%-95.9%), and the two-year OS rate was 83.9% (95% CI: 71.6%-92.2%).

CONCLUSIONS

Our findings indicate that this combination may be a potential neoadjuvant therapy regimen in this setting.

Total neoadjuvant therapy in oesophageal and gastro-oesophageal junctional adenocarcinoma

Adenocarcinoma of the oesophagus and gastro-oesophageal junction represent a large burden of cancer death in the Western World with an increasing incidence. In the past two decades, the overall survival of patients on a potentially curative treatment pathway has more than doubled due to the addition of perioperative oncological therapies to surgery. However, patients often fail to respond to oncological treatment or struggle to complete their treatment after surgery. In this review, we discuss the current evidence for total neoadjuvant therapy and options for assessment of treatment response.

Does the ypTNM-stage adequately predict long-term survival rates in gastric cancer patients receiving neoadjuvant chemotherapy followed by radical resection?

BACKGROUND

Following neoadjuvant chemotherapy (NAC) for resectable gastric cancer, the prognostic adequacy of the UICC staging system needs to be investigated. In particular to explore whether the ypTNM curves for radically resected gastric cancer patients receiving NAC follow the stage-matched survival curves of radically resected chemo-naïve patients (pTNM). Further, to disclose any interaction between the TNM-response mode to NAC and stage-specific survival rates, i.e., whether survival for a particular pathological disease stage was dependent on whether this was reached through a downstaging or as stable disease following NAC.

MATERIAL AND METHODS

Retrospective study on radically resected patients ≤ 75 years of age with gastric adenocarcinoma stages I-III diagnosed during 2001-2016. The patients constitute two population-based cohorts; the SURG-group with n = 121 patients treated before 2007 when NAC was introduced, and the NAC-group with n = 126 patients diagnosed since early 2007, receiving NAC and subsequent radical resection.

RESULTS

Long-term survival rates were similar when specific ypTNM-stages were compared to their corresponding pTNM chemo-naïve counterparts. The dichotomised N0 vs. N + had a substantial impact on the long-term survival rates in both groups, however, no discrepancy in long-term survival rates between pN0 vs. ypN0, and pN + vs. ypN + was found. The pathological stage determined long-term survival rates irrespective of the baseline disease stage, as no interaction between the response mode and stage-specific survival rates was found.

CONCLUSIONS

Survival curves for specific ypTNM-stages following NAC did not differ from the corresponding survival curves of their chemo-naïve pTNM counterparts. The interpretation is that NAC affected the gastric cancer, lymph nodes, and micrometastases, in such a way that the final ypTNM-stage provided similar prognostic information as the chemo-naïve pTNM-stages. Survival rates were contingent on the final ypTNM-stages alone, and not influenced by the response mode to reach that particular disease stage, or predetermined by the original clinical TNM-stage.

Applying post-neoadjuvant pathologic stage as prognostic tool in esophageal squamous cell carcinoma

BACKGROUND

It is still uncertain whether the newly released eighth American Joint Committee on Cancer (AJCC) post-neoadjuvant pathologic (yp) tumor-node-metastasis (TNM) stage for esophageal carcinoma can perform well regarding patient stratification. The current study aimed to assess the prognostication ability of the eighth AJCC ypTNM staging system and attempted to explore how to facilitate the staging system for more effective evaluation of prognosis.

MATERIALS AND METHODS

A total of 486 patients treated with neoadjuvant radiotherapy/chemoradiotherapy (nRT/CRT) were enrolled. ypN stage was reclassified by recursive partitioning. Prognostic performance, monotonicity, homogeneity, and discriminatory of yp and modified yp (myp) staging systems were assessed by time-dependent receiver operating characteristic (ROC), linear trend log-rank test, likelihood ratio χ2 test, Harrell's c statistic, and Akaike information criterion (AIC).

RESULTS

The ypT stage, ypN stage, and pathologic response were significant prognostic factors of overall survival. Survival was not discriminated well using the eighth AJCC ypN stage and ypTNM stage. Recursive partitioning reclassified mypN0-N2 as metastasis in 0, 1-2, and ≥3 regional lymph nodes. Applying the ypT stage, mypN stage, and pathologic response to construct the myp staging system, the myp stage performed better in time-dependent ROC, linear trend log-rank test, likelihood ratio χ2 test, Harrell's c statistic, and AIC.

CONCLUSIONS

The eighth AJCC ypTNM staging system performed well in differentiating prognosis to some extent. By reclassifying the ypN stage and enrolling pathologic response as a staging element, the myp staging system holds significant potential for prognostic discrimination.

Prognostic relevance of lymph node regression on survival in esophageal cancer: a systematic review and meta-analysis

INTRODUCTION

The prognostic value of histomorphologic regression in primary esophageal cancer has been previously established, however the impact of lymph node (LN) response on survival still remains unclear. The aim of this review was to assess the prognostic significance of LN regression or downstaging following neoadjuvant therapy for esophageal cancer.

METHODS

An electronic search was performed to identify articles evaluating LN regression or downstaging after neoadjuvant therapy. Random effects meta-analyses were performed to assess the influence of regression in the LNs and nodal downstaging on overall survival. Histomorphologic tumor regression in LNs was defined by the absence of viable cells or degree of fibrosis on histopathologic examination. Downstaged LNs were defined as pN0 nodes by the tumor, node, and metastasis classification, which were positive prior to treatment neoadjuvant.

RESULTS

Eight articles were included, three of which assessed tumor regression (number of patients = 292) and five assessed downstaging (number of patients = 1368). Complete tumor regression (average rate of 29.1%) in the LNs was associated with improved survival, although not statistically significant (hazard ratio [HR] = 0.52, 95% confidence interval [CI] = 0.26-1.06; P = 0.17). LNs downstaging (average rate of 32.2%) was associated with improved survival compared to node positivity after neoadjuvant treatment (HR = 0.41, 95%CI = 0.22-0.77; P = 0.005).

DISCUSSION

The findings of this meta-analysis have shown a survival benefit in patients with LN downstaging and are suggestive for considering LN downstaging to ypN0 as an additional prognostic marker in staging and in the comparative evaluation of differing neoadjuvant regimens in clinical trials. No statistically significant effect of histopathologic regression in the LNs on long-term survival was seen.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Tumor downstaging after neoadjuvant chemotherapy determines survival after surgery for gastric adenocarcinoma

BACKGROUND

Since 2006, surgery combined with perioperative chemotherapy is the standard of care for resectable gastric adenocarcinoma in Europe. Specific effects of neoadjuvant chemotherapy remain unknown. The aim was to evaluate the rate of tumor downstaging and its impact on survival in patients undergoing curative resection after neoadjuvant chemotherapy (NeoCT) for gastric adenocarcinoma.

MATERIAL AND METHODS

All patients treated in a curative intent for gastric or esophagogastric junction adenocarcinomas between 1996 and 2016 in our high-volume center were retrospectively included. Tumor downstaging after NeoCT was defined as ypTN inferior to cTN. The accuracy of clinical staging was evaluated in patients treated by upfront surgery before 2006.

RESULTS

During the study period, 491 patients were operated for gastric adenocarcinoma, and 449 patients were finally analyzed. Among the 163 (36.3%) patients who received NeoCT, 61 (37.4%) had tumor downstaging. Overall survival and disease-free survival were longer in patients with tumor downstaging compared to patients without it (5-year survival: 84.8% vs 49.7%; P = .002 and 61.7% vs 43.4%; P = .054). In multivariate analysis tumor downstaging was an independent prognosis factor for better overall survival (HR = 5.258; P = .002) and disease-free survival (HR = 2.286; P = .028). Moreover, 45.5% of patients staged cT1-T2N0, in whom upfront surgery was performed, were understaged and ultimately had a more advanced tumor on pathological analysis.

CONCLUSION

Response to neoadjuvant chemotherapy constitutes a major prognostic factor for overall and disease-free survival. In the absence of predictive factors for tumor downstaging, the indication for perioperative chemotherapy should remain broad, in particular because of the low accuracy of pretherapeutic staging and therefore the high risk of understaging tumors.

The Prognostic Value of the Lymph Node in Oesophageal Adenocarcinoma; Incorporating Clinicopathological and Immunological Profiling

Response rates to the current gold standards of care for treating oesophageal adenocarcinoma (OAC) remain modest with 15-25% of patients achieving meaningful pathological responses, highlighting the need for novel therapeutic strategies. This study consists of immune, angiogenic, and inflammatory profiling of the tumour microenvironment (TME) and lymph node microenvironment (LNME) in OAC. The prognostic value of nodal involvement and clinicopathological features was compared using a retrospective cohort of OAC patients (n = 702). The expression of inhibitory immune checkpoints by T cells infiltrating tumour-draining lymph nodes (TDLNs) and tumour tissue post-chemo(radio)therapy at surgical resection was assessed by flow cytometry. Nodal metastases is of equal prognostic importance to clinical tumour stage and tumour regression grade (TRG) in OAC. The TME exhibited a greater immuno-suppressive phenotype than the LNME. Our data suggests that blockade of these checkpoints may have a therapeutic rationale for boosting response rates in OAC.

Circulating Hybrid Cells: A Novel Liquid Biomarker of Treatment Response in Gastrointestinal Cancers

BACKGROUND

Real-time monitoring of treatment response with a liquid biomarker has potential to inform treatment decisions for patients with rectal adenocarcinoma (RAC), esophageal adenocarcinoma (EAC), and colorectal liver metastasis (CRLM). Circulating hybrid cells (CHCs), which have both immune and tumor cell phenotypes, are detectable in the peripheral blood of patients with gastrointestinal cancers, but their potential as an indicator of treatment response is unexplored.

METHODS

Peripheral blood specimens were collected from RAC and EAC patients after neoadjuvant therapy (NAT) or longitudinally during therapy and evaluated for CHC levels by immunostaining. Receiver operating characteristics (ROCs) and the Kaplan-Meier method were used to analyze the CHC level as a predictor of pathologic response to NAT and disease-specific survival (DSS), respectively.

RESULTS

Patients with RAC (n = 23) and EAC (n = 34) were sampled on the day of resection, and 11 patients (32%) demonstrated a pathologic complete response (pCR) to NAT. On ROC analysis, CHC levels successfully discriminated pCR from non-pCR with an area under the curve of 0.82 (95% confidence interval [CI], 0.71-0.92; P < 0.001). Additionally, CHC levels in the EAC patients correlated with residual nodal involvement (P = 0.026) and 1-year DSS (P = 0.029). The patients with RAC who were followed longitudinally during NAT (n = 2) and hepatic arterial infusion therapy for CRLM (n = 2) had CHC levels that decreased with therapy response and increased before clinical evidence of disease progression.

CONCLUSION

Circulating hybrid cells are a novel blood-based biomarker with potential for monitoring treatment response and disease progression to help guide decisions for further systemic therapy, definitive resection, and post-therapy surveillance. Additional validation studies of CHCs are warranted.

Does a high Mandard score really define a poor response to chemotherapy in oesophageal adenocarcinoma?

BACKGROUND

A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.

METHODS

Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.

RESULTS

Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1-3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16-0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (-16.3 vs -7.7 cm³, p = 0.033) with no significant difference between Mandard groups.

CONCLUSION

Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.

The Impact of Pretreatment PET/CT Nodal Status on Esophageal Squamous Cell Carcinoma After Neoadjuvant Chemoradiation

BACKGROUND

For advanced esophageal cancer, the clinical significance of pretreatment nodal status (cN) as determined by different examinations remains unclear.

PATIENTS AND METHODS

Patients with esophageal squamous cell carcinoma who underwent neoadjuvant chemoradiation and surgery were analyzed in this study. Pretreatment cN status assessed by CT, EUS, and PET/CT and clinicopathological features were used to evaluate tumor recurrence and long-term survival.

RESULTS

Two hundred and twenty-two patients were identified in this study. Pretreatment PET/CT cN0 [odds ratio (OR) cN0 versus cN+, 5.316, p < 0.001] and pretreatment CT cN0 (OR 1.957, p = 0.032) both independently predicted ypN0. Pretreatment PET/CT cN0 was also associated with a lower recurrence rate and longer survival across the entire study group. Among patients with ypN0, pretreatment PET/CT cN+ indicated poor disease-free survival [hazard ratio (HR) 2.777, p = 0.001] and overall survival (HR 2.211, p = 0.034) compared with pretreatment PET/CT cN0, which predicted a favorable prognosis.

CONCLUSIONS

Data from the current study suggest that pretreatment lymph node status as assessed by PET/CT is strongly correlated with survival outcomes after neoadjuvant chemoradiation and surgery in patients with esophageal squamous cell carcinoma. ypN0 patients can achieve better survival outcomes when pretreatment cN0 is assessed by PET/CT.

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

Purpose

Nodal downstaging after preoperative therapy for gastric cancer has been shown to impart excellent prognosis, but this has not been validated in a national cohort. The role of neoadjuvant chemoradiation (NACR) in nodal downstaging remains unclear when compared with that of neoadjuvant chemotherapy alone (NAC). Furthermore, it is unknown whether the prognostic implications of nodal downstaging differ by preoperative regimen.

Materials and Methods

Using the National Cancer Database, overall survival (OS) duration was compared among natural N0 (cN0/ypN0), downstaged N0 (cN+/ypN0), and node-positive (ypN+) gastric cancer patients treated with NACR or NAC. Factors associated with nodal downstaging were examined in a propensity score-matched cohort of cN+ patients, matched 1:1 by receipt of NACR or NAC.

Results

Of 7,426 patients (natural N0 [n=1,858, 25.4%], downstaged N0 [n=1,813, 24.4%], node-positive [n=3,755, 50.4%]), 58.2% received NACR, and 41.9% received NAC. The median OS durations of downstaged N0 (5.1 years) and natural N0 (5.6 years) patients were similar to one another and longer than that of node-positive patients (2.1 years) (P<0.001). In the matched cohort of cN+ patients, more recent diagnosis (2010–2015 vs. 2004–2009) (odds ratio [OR], 2.57; P<0.001) and NACR (OR, 2.02; P<0.001) were independently associated with nodal downstaging. The 5-year OS rate of downstaged N0 patients was significantly lower after NACR (46.4%) than after NAC (57.7%) (P=0.003).

Conclusions

Downstaged N0 patients have the same prognosis as natural N0 patients. Nodal downstaging occurred more frequently after NACR; however, the survival benefit of nodal downstaging after NACR may be less than that when such is achieved by NAC.

Nodal Downstaging of Esophageal Squamous Cell Carcinoma after Neoadjuvant Chemoradiotherapy: Survival Analysis if ypN0 Is Achieved

BACKGROUND

It is known that ypN0 status after induction treatment can be divided into "natural" N0 (cN0/ypN0) and "downstaged" N0 (cN+/ypN0). Whether natural N0 patients and downstaged N0 patients with esophageal squamous cell carcinoma (ESCC) after neoadjvant chemoradiotherapy (nCRT) have similar prognosis is unknown.

METHODS

An institutional database was reviewed to identify ESCC patients after nCRT, whose CT scans were retrieved and reviewed to reclassify nodal status. The patients were divided into 3 groups based on node status: natural N0, downstaged N0, and ypN+. Impact of nodal status on survival and associations with survival were analyzed.

RESULTS

We identified 110 patients, and 25 had natural N0 disease, 52 had downstaged N0 disease, and 33 had ypN+ disease. The 3-year OS was 76.7%, 79.5%, and 49% in natural N0, downstaged N0 and ypN+ group, respectively, and, correspondingly, the 3-year DFS was 77%, 73.9%, and 36.3%. In multivariable analysis, OS (P = 0.794) and DFS (P = 0.957) did not differ between natural N0 and downstaged N0 groups, but it was significantly shorter in ypN+ group (OS, P = 0.032; DFS, P = 0.021). In subgroups with "poor response" of primary tumor, the prognosis of natural N0 and downstaged N0 paitents was poor almost identical to ypN+ in both OS (P = 0.721; P = 0.252) and DFS (P = 0.694; P = 0.114).

CONCLUSIONS

The ypN0 status is an important hallmark demonstrating the effectiveness of nCRT for ESCC, regardless of cN status. Additionally, the survival of natural N0 and downstaged N0 patients with bad response at primary site may be poor, similar to ypN+ patients.

Precision Surgical Therapy for Adenocarcinoma of the Esophagus and Esophagogastric Junction

INTRODUCTION

To facilitate the initial clinical decision regarding whether to use esophagectomy alone or neoadjuvant therapy in surgical care for individual patients with adenocarcinoma of the esophagus and esophagogastric junction-information not available from randomized trials-a machine-learning analysis was performed using worldwide real-world data on patients undergoing different therapies for this rare adenocarcinoma.

METHODS

Using random forest technology in a sequential analysis, we (1) identified eligibility for each of four therapies among 13,365 patients: esophagectomy alone (n = 6649), neoadjuvant therapy (n = 4706), esophagectomy and adjuvant therapy (n = 998), and neoadjuvant and adjuvant therapy (n = 1022); (2) performed survival analyses incorporating interactions of patient and cancer characteristics with therapy; (3) determined optimal therapy as that predicted to maximize lifetime within 10 years (restricted mean survival time; RMST) for each patient; and (4) compared lifetime gained from optimal versus actual therapies.

RESULTS

Actual therapy was optimal in 61% of those receiving esophagectomy alone; neoadjuvant therapy was optimal for 36% receiving neoadjuvant therapy. Many patients were predicted to benefit from postoperative adjuvant therapy. Total RMST for actual therapy received was 58,825 years. Had patients received optimal therapy, total RMST was predicted to be 62,982 years, a 7% gain.

CONCLUSIONS

Average treatment effect for adenocarcinoma of the esophagus yields only crude evidence-based therapy guidelines. However, patient response to therapy is widely variable, and survival after data-driven predicted optimal therapy often differs from actual therapy received. Therapy must address an individual patient's cancer and clinical characteristics to provide precision surgical therapy for adenocarcinoma of the esophagus and esophagogastric junction.

Reliability of clinical nodal status regarding response to neoadjuvant chemoradiotherapy compared with surgery alone and prognosis in esophageal cancer patients

Background: Clinical nodal (cN) staging is a key element in treatment decisions in patients with esophageal cancer (EC). The reliability of cN status regarding the effect on response and survival after neoadjuvant chemoradiotherapy (nCRT) with esophagectomy was evaluated in determining the up- and downstaged pathological nodal (pN) status after surgery alone. Material and methods: From a prospective database, we included all 395 EC patients who had surgery with curative intent with or without nCRT between 2000 and 2015. All patients were staged by a standard pretreatment protocol: 16-64 mdCT, 18 F-FDG-PET or 18 F-FDG-PET/CT and EUS ± FNA. After propensity score matching on baseline clinical tumor and nodal (cT/N) stage and histopathology, a surgery-alone and nCRT group (each N = 135) were formed. Clinical and pathological N stage was scored as equal (cN = pN), downstaged (cN > pN) or upstaged (cN < pN). Prognostic impact on disease free survival (DFS) was assessed with multivariable Cox regression analysis (factors with p value <.1 on univariable analysis). Results: The surgery-alone and nCRT group did not differ in cT/N status. Pathologic examination revealed equal staging (32 vs. 27%), nodal up (43 vs. 16%) and downstaging (25 vs. 56%), respectively (p < .001). Nodal up-staging was common in cT3-4a tumors and adenocarcinomas in the surgery-alone group, while nodal downstaging was found in half of cT1-2 and cT3-4 regardless of tumortype after nCRT. Prognostic factors for DFS were pN (p = .002) and lymph-angioinvasion (p = .016) in surgery-alone, and upper abdominal cN metastases (p = .012) and lymph node ratio (p = .034) in the nCRT group. Conclusions: Despite modern staging methods, correct cN staging remains difficult in EC. Nodal overstaging (cN > pN) occurred more often than understaging impeding an adequate assessment of pathologic complete response and prognosis after nCRT.

Low- vs. High-Dose Neoadjuvant Radiation in Trimodality Treatment of Locally Advanced Esophageal Cancer

BACKGROUND

The optimal dose of neoadjuvant radiation for locally advanced, resectable esophageal cancer remains controversial in the absence of randomized clinical trials, with conventional practice favoring the use of 50.4 vs. 41.4 Gy.

METHODS

Retrospective analysis of adults with non-metastatic esophageal cancer in the National Cancer Database (2004-2015) treated with neoadjuvant chemoradiotherapy. Outcomes were compared between patients undergoing 41.4, 45, or 50.4 Gy. Primary outcome was overall survival. Secondary outcomes included T and N downstaging and perioperative mortality adjusted for demographics, clinicopathologic factors, and facility volume.

RESULTS

Eight thousand eight hundred eighty-one patients were included: 439 (4.9%) received low-dose (41.4 Gy), 2194 (24.7%) received moderate-dose (45 Gy), and 6248 (70.4%) received high-dose (50.4 Gy) neoadjuvant radiation. Compared to high-dose, low-dose radiation was associated with superior median overall survival (52.6 vs. 40.7 months) and 5-year survival (48.3% vs. 40.2%), and lower unadjusted 90-day mortality (2.3% vs. 6.5%, all p ≤ 0.01). Multivariable proportional hazards models confirmed an increased hazard of death associated with high-dose radiation therapy (HR = 1.38, 95% CI 1.10-1.72, p = 0.005). There was no significant difference in T and/or N downstaging between low-dose vs. high-dose therapy (p > 0.1 for both). Patients receiving 45 Gy exhibited the lowest median overall survival (37.2 months) and 5-year survival (38.7%, log-rank p = 0.04).

CONCLUSIONS

Compared to 50.4 Gy, 41.4 Gy is associated with reduced perioperative mortality and superior overall survival with similar downstaging in locally advanced esophageal cancer. In the absence of randomized clinical data, our findings support the use of 41.4 Gy in patients with chemoradiation followed by esophagectomy. Prospective trials are warranted to further validate these results.

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.

Nodal Downstaging in Gastric Cancer Patients: Promising Survival if ypN0 is Achieved

BACKGROUND

The American Joint Committee on Cancer's 8th edition introduced ypStage, a separate staging system for patients with gastric cancer having undergone preoperative therapy. Overall, ypN0 patients have better survival outcomes than ypN+ patients. However, whether patients with cN+/ypN0 disease ("downstaged N0") and those with cN0/ypN0 disease ("natural N0") have similar survival is unknown.

METHODS

An institutional database was reviewed to identify gastric adenocarcinoma patients who underwent potentially curative R0 resection after induction chemotherapy or chemoradiation. Patients were categorized into three groups based on nodal status: cN0/ypN0, cN+/ypN0, and ypN+. Univariable and multivariable Cox regression models were used to identify clinicopathologic factors associated with overall survival (OS).

RESULTS

We identified 316 patients who met the study criteria. Ninety-four patients (30%) had cN0/ypN0 disease, 93 (29%) had cN+/ypN0 disease, and 129 (41%) had ypN+ disease. The median OS was 7.7 years, and the 5-year OS was 60.3%. In the multivariate analysis, OS did not differ between the cN0/ypN0 and cN+/ypN0 patients (hazard ratio, 0.90 [95% CI 0.54-1.48]; p = 0.666), but it was shorter in ypN+ patients (hazard ratio, 1.82 [95% CI 1.15-2.87]; p = 0.01).

CONCLUSIONS

In gastric cancer patients who underwent preoperative therapy, we found similar OS in cN0/ypN0 and cN+/ypN0 patients. Because ypN+ patients had poor OS, achieving ypN0 status is an important hallmark demonstrating the effectiveness of preoperative therapy for gastric cancer.

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.

Evaluation of the American Joint Committee on Cancer 8th edition staging system for gastric cancer patients after preoperative therapy

BACKGROUND

The American Joint Committee on Cancer (AJCC) recently released its 8th edition staging system, which created a separate staging system for gastric cancer patients who have undergone preoperative therapy (ypStage). The objective of this retrospective study was to apply the new ypStage to patients who have undergone preoperative therapy and potentially curative gastrectomy.

METHODS

We collected data from a prospectively maintained institutional database of gastric cancer patients who underwent potentially curative gastrectomy after preoperative therapy (1995-2015). Kaplan-Meier survival estimations and log-rank tests were performed to compare survival. Univariable and multivariable analyses were performed to determine risk factors for overall survival.

RESULTS

A total of 354 patients met our criteria. Most patients completed planned preoperative therapy (94%; 332/354) and received chemoradiation therapy (75%; 265/354). Although clinical stage (cStage) provided a poor discrimination of survival, postneoadjuvant pathological stage (ypStage) identified significant variation in survival (p < 0.001). Multivariable analysis showed the following factors were associated with survival after adjustment for ypStage: Asian race (HR 0.52; p = 0.028), linitis plastica (HR 1.66; p = 0.037), and R1 resection (HR 1.91; p = 0.016). Survival was not longer in ypT0N0 patients than in ypStage I patients (HR 1.29; p = 0.377).

CONCLUSIONS

The AJCC 8th edition staging system for gastric cancer demonstrated reasonable survival prediction by ypStage, but not cStage, in patients who had undergone preoperative therapy. ypT0N0 patients, although not defined in the 8th edition, may be considered for inclusion in the ypStage I group.