Theoretical therapeutic impact of lymph node dissection on adenocarcinoma and squamous cell carcinoma of the esophagogastric junction

Surgical and Perioperative Treatments for Esophagogastric Junction Cancer

Esophagogastric junction cancer (EGJC) is a rare malignant disease that occurs in the gastroesophageal transition zone. In recent years, its incidence has been rapidly increasing not only in Western countries but also in East Asia, and it has been attracting the attention of both clinicians and researchers. EGJC has a worse prognosis than gastric cancer (GC) and is characterized by complex lymphatic drainage pathways in the mediastinal and abdominal regions. EGJC was previously treated in the same way as GC or esophageal cancer, but, in recent years, it has been treated as an independent malignant disease, and treatment focusing only on EGJC has been developed. A recent multicenter prospective study revealed the frequency of lymph node metastasis by station and established the optimal extent of lymph node dissection. In perioperative treatment, the combination of multi-drug chemotherapy, radiation therapy, molecular targeted therapy, and immunotherapy is expected to improve the prognosis. In this review, we summarize previous clinical trials and their important evidence on surgical and perioperative treatments for EGJC.

Essential updates 2021/2022: Perioperative and surgical treatments for gastric and esophagogastric junction cancer

In recent years, important clinical trials for gastric cancer (GC) and esophagogastric junction cancer (EGJC) have been reported, changing the strategies of surgical and perioperative treatment. Although laparoscopic gastrectomy has already been shown to be effective for early-stage cancer, recent evidence from both Asia (JLSSG0901, CLASS-01 and KLASS-02) and Europe (LOGICA and STOMACH trials) has demonstrated that it is useful for advanced GC. Robotic surgery has been rapidly gaining popularity in recent years, and randomized controlled trials are ongoing to evaluate its efficacy. A prospective nationwide multicenter study mapped sites with frequent metastasis and revealed lymphatic flow specific to EGJC, thus establishing the optimal lymph node dissection area and surgical approach based on esophageal involvement. Perioperative chemotherapy, the mainstay of treatment in Europe, also has been established in Asia by the PRODIGY and RESOLVE studies. New clinical trials have been conducted to evaluate the efficacy of combining immunotherapy or molecular-targeted therapy with perioperative chemotherapy or chemoradiotherapy. In this review, we present important recent clinical trials regarding the treatment of GC and EGJC published in 2021 or 2022.

Management of Esophago-Gastric Junction Carcinoma: A Narrative Multidisciplinary Review

Esophagogastric junction (EGJ) carcinoma represents a specific site of disease, given the opportunities for multimodal clinical care and management and the possibilities of combined treatments. It encompasses various clinical subgroups of disease that are heterogeneous and deserve different treatments; therefore, the guidelines have progressively evolved over time, considering the evidence provided by clinical trials. The aim of this narrative review was to summarize the main evidence, which orientates the current guidelines, and to collect the main ongoing studies to address existing gray areas.

Mapping of lymph node dissection determined by the epicenter location and tumor extension for esophagogastric junction carcinoma

Backgrounds

Previous studies identified the extent of lymph node dissection for esophagogastric junction (EGJ) carcinoma based on the metastatic incidence. The study aimed to determine the optimal extent and priority of lymphadenectomy based on the therapeutic efficacy from each station.

Methods

The studies on the lymph node metastasis (LNM) and therapeutic efficacy index (EI) for EGJ carcinomas were identified until April 2022. The obligatory stations with the LNM rates over 5% and therapeutic EI exceeding 2% should be routinely resected for D2 dissection, whereas the optional stations with EI between 0.5% and 2% should be resected for D3 dissection in selective cases.

Results

The survey yielded 16 eligible articles including 6,350 patients with EGJ carcinoma. The metastatic rates exceeded 5% at no. 1, 2, 3, 7, 9, 11p, and 110 stations and were less than 5% in abdominal no. 4sa~6, 8a, 10, 11d, 12a, and 16a2/b1 and mediastinal no. 105~112 stations. Consequently, obligatory stations with EI over 2% were largely determined by the epicenter location and located at the upper perigastric, lower mediastinal, and suprapancreatic zones, corresponding to those with rates of LNM over 5%. Consistent with the LNM rates less than 5%, the optional stations with EI between 0.5% and 2% were largely dependent on the degree of tumor extension toward the lower perigastric, splenic hilar (grecurvature), para-aortic (less curvature of the cardia), and middle or upper mediastinal zones.

Conclusions

The obligatory stations can be resected as an “envelope-like” wrap by transhiatal proximal gastrectomy with lower esophagectomy, whereas the optional stations for dissection are indicated by the tumor extension. The extended gastrectomy is required for the lower perigastric in the stomach-predominant tumor with gastric involvement exceeding 5.0 cm, para-aortic dissection in the less curvature-predominant tumor and splenic hilar dissection in the grecurvature-predominant tumor whereas transthoracic subtotal esophagectomy is required for complete mediastinal dissection and adequate negative margin in the esophagus-predominant tumor with esophageal invasion exceeding 3.0 cm.

Risk Factors for Para-Aortic Lymph Node Metastasis in Esophagogastric Junction Cancer: Results from a Prospective Nationwide Multicenter Study

BACKGROUND

Several studies have reported a high incidence of metastasis to para-aortic station 16a2lat (no. 16a2lat) among patients with esophagogastric junction (EGJ) cancer. However, the risk factors for no. 16a2lat metastasis are unclear. This study aimed to clarify the risk factors for no. 16a2lat metastasis in patients with EGJ cancer.

METHODS

Among 371 prospectively enrolled patients with EGJ cancer, 344 patients who underwent no. 16a2lat lymph node dissection were analyzed. Background factors were compared between the patients with and those without no. 16a2lat metastasis. The association between the histologic status of 10 regional lymph node stations and that of no. 16a2lat metastasis was evaluated.

RESULTS

Among the background factors, clinical N2-3 was the only independent risk factor for no. 16a2lat metastasis (odds ratio [OR], 5.90; p = 0.003). The metastasis rate of no. 16a2lat was 11.8% (11/93) for the patients with cN2-3 disease and 2.0% (5/251) for those with cN0-1 disease. The multivariate analysis showed that nos. 2 and 7 metastases were independent risk factors for no. 16a2lat metastasis, with respective ORs of 5.53 (p = 0.018) and 4.00 (p = 0.041). The patients with neither station no. 2 nor no. 7 metastasis did not exhibit no. 16a2lat metastasis, whereas the rate of no. 16a2lat metastasis was 23.7% for the patients with metastases of both stations.

CONCLUSIONS

Clinical N2-3 and histologic positivity of station nos. 2 and 7 were independent risk factors for no. 16a2lat metastasis. These findings could potentially assist in determining the indication for no. 16a2lat dissection for patients with EGJ cancer.

Feasibility of Preserving No. 5 and No. 6 Lymph Nodes in Gastrectomy of Proximal Gastric Adenocarcinoma: A Retrospective Analysis of 395 Patients

Objective

The extent of regional lymphadenectomy for proximal gastric cancer (PGC) has remained a controversy and a matter of considerable debate for a long time. We retrospectively analyzed the clinicopathological features to investigate the predictive factors for No. 5 and/or No. 6 lymph node metastases (LNMs) and evaluate the feasibility of performing proximal gastrectomy (PG) with preservation of No. 5 and/or No. 6 lymph nodes for these patients.

Method

Patients who had undergone total gastrectomy plus D2 lymphadenectomy in the Department of Gastrointestinal Surgery, Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, from January 2008 to December 2017 were retrospectively collected and analyzed.

Results

Among the 395 eligible patients in our study, 34 patients (8.61%) had No. 5 and No. 6 LNM. The degree of differentiation, Borrmann classification, vascular or perineural invasion, tumor diameter, depth of invasion, and other perigastric LNM were associated with No. 5 and/or No. 6 LNM. Multivariate analyses showed that tumor diameter ≥4 cm, No. 4 LNM positive, and No. 7, No. 8, No. 9 LNM positive were independent risk factors of No. 5 and/or No. 6 LNM. No. 5 and/or No. 6 LNM was not observed in the 105 patients who were staged from T1 to T3 and were found to be without independent risk factors.

Conclusion

The metastatic rate of No. 5 and/or No. 6 lymph node of the proximal gastric adenocarcinoma was closely associated with the diameter of the tumor and other perigastric LNMs. It is feasible to preserve No. 5 and No. 6 lymph nodes with PG for the T1-T3 patients with lower risk of No. 5 and/or No. 6 LNM.

Surgical and perioperative treatment strategy for resectable esophagogastric junction cancer

Esophagogastric junction cancer is defined as adenocarcinoma with the epicenter within 5 cm of the esophagogastric junction in the West according to the Siewert classification. In contrast, it is defined as cancer of any histological type with the epicenter located within 2 cm proximal or distal to the esophagogastric junction in Japan according to the Nishi classification. Recently, the incidence of esophagogastric junction cancer has been rapidly rising all over the world, leading to much attention. Esophagogastric junction cancer was previously treated like gastric cancer or esophageal cancer because it is a less frequently occurring tumor. Esophagogastric junction cancer is considered to have worse prognosis than gastric cancer. Therefore, in recent years, esophagogastric junction cancer has been recognized as an independent malignant disease with poor prognosis, and thus development of treatment strategies focused on esophagogastric junction cancer is needed. The mapping of frequent metastasis in the mediastinal and abdominal lymph nodes has revealed the lymphatic flow from esophagogastric junction cancer specifically, establishing the optimal lymph node dissection area and surgical approach. The development of multimodal treatment that includes chemotherapy, radiotherapy and immunotherapy has been applied to improve the survival of esophagogastric junction cancer. In this review, we summarize clinical trials with important evidence on surgical and multimodal perioperative treatments for esophagogastric junction cancer.

Postoperative complications after a transthoracic esophagectomy or a transhiatal gastrectomy in patients with esophagogastric junctional cancers: a prospective nationwide multicenter study

BACKGROUND

Esophagogastric junction (EGJ) cancers are resected thorough esophagectomy or gastrectomy, with the incidence of postoperative complications influenced by the chosen procedure.

METHODS

In this prospective nationwide multicenter study, patients with cT2-T4 EGJ cancers were enrolled before surgery. Based on the protocol, surgeons performed a transthoracic esophagectomy (TTE) or a transhiatal gastrectomy (THG) and dissected all lymph nodes prespecified as the standardized procedure. Postoperative complications were correlated with the clinical factors in each procedure.

RESULTS

A total of 345 patients were eligible for this study. TTE and THG were performed in 120 and 225 patients, respectively. Complications of Clavien-Dindo ≥ Grade II were found in 115/345 (33.3%) patients. Recurrent laryngeal nerve palsy was found only in the TTE group (p < 0.001). The incidence of other complications was not significantly different between the two groups. High body mass index (BMI) in the TTE group, male sex, and longer esophageal invasion in the THG group were significantly correlated with complications ≥ Grade II (p = 0.049, 0.037, and 0.019, respectively). Anastomotic leakage was most frequently observed (12.2%). Tumor size in the THG group (p = 0.02) was significantly associated with leakage. All six patients with ≥ Grade IV leakage underwent THG, whereas, none of the patients in the TTE group had leakage ≥ Grade IV (2.7% vs. 0%, p = 0.096).

CONCLUSIONS

Surgical resection should be performed with utmost care, particularly in patients with a high BMI undergoing TTE, and in patients with larger tumors, longer esophageal invasion, or male patients undergoing THG.

The Value of Paratracheal Lymphadenectomy in Esophagectomy for Adenocarcinoma of the Esophagus or Gastroesophageal Junction: A Systematic Review of the Literature

Background

The role of upper mediastinal lymphadenectomy for distal esophageal or gastroesophageal junction (GEJ) adenocarcinomas remains a matter of debate. This systematic review aims to provide a comprehensive overview of evidence on the incidence of nodal metastases in the upper mediastinum following transthoracic esophagectomy for distal esophageal or GEJ adenocarcinoma.

Methods

A literature search was performed using Medline, Embase and Cochrane databases up to November 2020 to include studies on patients who underwent transthoracic esophagectomy with upper mediastinal lymphadenectomy for distal esophageal and/or GEJ adenocarcinoma. The primary endpoint was the incidence of metastatic nodes in the upper mediastinum based on pathological examination. Secondary endpoints were the definition of upper mediastinal lymphadenectomy, recurrent laryngeal nerve (RLN) palsy rate and survival.

Results

A total of 17 studies were included and the sample sizes ranged from 10-634 patients. Overall, the median incidence of upper mediastinal lymph node metastases was 10.0% (IQR 4.7-16.7). The incidences of upper mediastinal lymph node metastases were 8.3% in the 7 studies that included patients undergoing primary resection (IQR 2.0-16.6), 4,4% in the 1 study that provided neoadjuvant therapy to the full cohort, and 10.6% in the 9 studies that included patients undergoing esophagectomy either with or without neoadjuvant therapy (IQR 8.9-15.8%). Data on survival and RLN palsy rates were scarce and inconclusive.

Conclusions

The incidence of upper mediastinal lymph node metastases in distal esophageal adenocarcinoma is up to 10%. Morbidity should be weighed against potential impact on survival.

Clinical significance of lower perigastric lymph nodes dissection in Siewert type II/III adenocarcinoma of esophagogastric junction: a retrospective propensity score matched study

PURPOSE

The optimal surgical procedure, whether total gastrectomy (TG) or proximal gastrectomy (PG), for Siewert type II/III adenocarcinoma of esophagogastric junction (AEG) has not been standardised, primarily because the optimal extent of lymph node (LN) dissection for AEG based on the metastatic rate of perigastric LNs remains under debate. The aim of this study was to investigate the metastatic incidence and prognostic significance of lower perigastric lymph nodes (LPLN), including No.4d, 5, 6 and 12a LN stations, in Siewert type II/III AEG.

METHODS

A total of 701 patients with Siewert type II/III AEG who received transabdominal open gastrectomy (425 patients with TG and 276 patients with PG) from 2010 to 2015 in West China Hospital were retrospectively included. Based on the clinicopathological information of TG patients, the risk factors of LPLN-positive patients were evaluated, and the metastatic incidence as well as the therapeutic value (TV) index of each LN station was assessed. Moreover, the 5-year overall survival (OS) rates between LPLN-positive and LPLN-negative groups were compared in TG patients, and the postoperative survival difference between TG and PG patients was also compared, using propensity score matching (PSM) method.

RESULTS

Tumour size (≥ 5 cm, OR = 1.481, p = 0.002) and pT stage (pT4, OR = 2.755, p = 0.024) were significant risk factors for patients with LPLN metastasis. For patients with tumour size more than 5 cm or pT4 stage, the metastatic rates of LPLN for Siewert type II, III and II/III AEG were 31.67%, 34.69% and 33.03%, whereas the TV indexes of LPLN for them were 5.76, 5.62 and 5.38, respectively. LPLN was a significant independent prognostic factor (HR = 1.422, p = 0.028), and positive LPLN was related to worse prognosis (p < 0.05). For patients with tumour size more than 5 cm or pT4 stage, TG patients were illustrated to have a better prognosis than PG patients, with 5-year OS rates of 58.9% vs 38.2% for Siewert type II AEG (χ2 = 4.159, p = 0.041), 68.9% vs 50.2% for Siewert type III AEG (χ2 = 5.630, p = 0.018) and 65.1% vs 40.3% for Siewert type II/III AEG (χ2 = 12.604, p < 0.001), respectively.

CONCLUSIONS

LPLN metastasis is a poor prognostic factor for patients with Siewert II/III AEG. LPLN dissection may improve the long-term survival of patients with tumour size more than 5 cm or pT4 stage, and TG might be more suitable for this kind of cancer.

Optimal surgery for esophagogastric junctional cancer

Esophagogastric junctional cancer is classified into three categories according to the Siewert classification, which reflects the epidemiological and biological characteristics. Therapeutic strategies have been evaluated according to the three Siewert types. There is a consensus that types I and III should be treated as esophageal cancer and gastric cancer, respectively. On the other hand, type II is often described as true cardiac cancer, which has different clinicopathological features from the other types. Thus, there is no consensus on the surgical management of type II esophagogastric junctional cancer. The optimal surgical management should focus on the principles of cancer surgery, which take into consideration oncological curability, including an appropriate resection margin, adequate lymphadenectomy, and minimization of postoperative complications. In this review, we evaluate the current relevant literature and evidence, on the surgical treatment of esophagogastric junctional cancer, focusing on type II. Esophagectomy with a thoracic approach has the advantage of ensuring a sufficient proximal resection margin and adequate mediastinal lymphadenectomy. However, the oncological benefit is offset by a high incidence of postoperative complications. Minimally invasive esophagectomy could be a possible solution to reduce complications and improve long-term outcomes. Further development of surgical treatments for Siewert type II is required to improve the outcomes. Furthermore, the surgical team should have expertise in both gastric cancer and esophageal cancer treatment, or patients should be managed with close collaboration between thoracic surgeons and gastric cancer surgeons.

Mapping of Lymph Node Metastasis From Esophagogastric Junction Tumors: A Prospective Nationwide Multicenter Study

OBJECTIVE

The aim of the study was to determine the optimal extent of lymph node dissection for the 2 histological types of esophagogastric junction (EGJ) tumors based on the incidence of metastasis in a prospective nationwide multicenter study.

BACKGROUND

Because most previous studies were retrospective, the optimal surgical procedure for EGJ tumors has not been standardized.

METHODS

Patients with cT2-T4 adenocarcinoma or squamous cell carcinoma located within 2.0 cm of the EGJ were enrolled before surgery. Surgeons dissected all lymph nodes prespecified in the protocol, using either the abdominal transhiatal or right transthoracic approach. The primary endpoint was the metastasis rate of each lymph node. Lymph nodes were classified according to metastasis rate, as follows: category-1 (strongly recommended for dissection), rate more than 10%; category-2 (weakly recommended for dissection), rate from 5% to 10%; and category-3 (not recommended for dissection), rate less than 5%.

RESULTS

Between 2014 and 2017, 1065 patients with EGJ tumor were screened, and 371 were enrolled. Among 358 patients who underwent surgical resection, category-1 nodes included abdominal stations 1, 2, 3, 7, 9, and 11p, whereas category-2 nodes included abdominal stations 8a, 19, and lower mediastinal station 110. If esophageal involvement exceeded 2.0 cm, station 110 was assigned to category-1. Among 98 patients who had either adenocarcinoma with esophageal involvement over 3.0 cm or squamous cell carcinoma, there were no category-1 nodes in the upper/middle mediastinal field, whereas category-2 nodes included upper mediastinal station 106recR and middle mediastinal station 108. When esophageal involvement exceeded 4.0 cm, station 106recR was assigned to category-1.

CONCLUSION

The study accurately identified the distribution of lymph node metastases from EGJ tumors and the optimal extent of subsequent lymph node dissection.

Esophagectomy or Total Gastrectomy for Siewert 2 Gastroesophageal Junction (GEJ) Adenocarcinoma? A Registry-Based Analysis

Backgrounds

Due to a lack of randomized and large studies, the optimal surgical approach for Siewert 2 gastroesophageal junctional (GEJ) adenocarcinoma remains unknown. This population-based cohort study aimed to compare survival between esophagectomy and total gastrectomy for the treatment of Siewert 2 GEJ adenocarcinoma.

Methods

Data from the National Cancer Database (NCDB) from 2010 to 2016 was used to identify patients with non-metastatic Siewert 2 GEJ adenocarcinoma who received either esophagectomy (n = 999) or total gastrectomy (n = 8595). Propensity score-matching (PSM) and multivariable analyses were used to account for treatment selection bias.

Results

Comparison of the unmatched cohort’s baseline demographics showed that the patients who received esophagectomy were younger, had a lower burden of medical comorbidities, and had fewer clinical positive lymph nodes. The patients in the unmatched cohort who received gastrectomy had a significantly shorter overall survival than those who received esophagectomy (median, 47 vs. 68 months [p < 0.001]; 5-year survival, 45 % vs. 53 %). After matching, gastrectomy was associated with significantly reduced survival compared with esophagectomy (median, 51 vs. 68 months [p < 0.001]; 5-year survival, 47 % vs. 53 %), which remained in the adjusted analyses (hazard ratio [HR], 1.22; 95 % confidence interval [CI], 1.09–1.35; p < 0.001).

Conclusions

In this large-scale population study with propensity-matching to adjust for confounders, esophagectomy was prognostically superior to gastrectomy for the treatment of Siewert 2 GEJ adenocarcinoma despite comparable lymph node harvest, length of stay, and 90-day mortality. Adequately powered randomized controlled trials with robust surgical quality assurance are the next step in evaluating the prognostic outcomes of these surgical strategies for GEJ cancer.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10346-x.

Screening and clinical significance of lymph node metastasis-related genes within esophagogastric junction adenocarcinoma

Background

Despite recent improvements in treatment technologies, such as surgical resection and chemoradiotherapy, the prognosis of patients with esophagogastric junction adenocarcinoma (EJA) remains poor due to early lymph node metastasis. Since few studies have investigated genes associated with lymph node metastasis in EJA, we aimed to screen lymph node metastasis‐associated genes and clarify their expression status and prognostic significance in EJA.

Methods

The differential frequency of mutations between carcinoma and para‐carcinoma tissues from 199 cases with EJA was detected using targeted next‐generation sequencing (tNGS). Following a stratified analysis to determine that gender has no effect on the frequency of gene mutations, lymph node metastasis‐related genes, including CDK6, MET, NOTCH1, and LRP1B, were screened, and CDK6 and LRP1B were selected for further study as they displayed significant differences in mutation rates. Differences in their expression status were verified using immunohistochemical (IHC) staining in 18 CDK6‐ and 17 LRP1B‐mutated samples and a randomly matched control group.

Results

tNGS revealed that CDK6 and LRP1B mutation frequencies were significantly different between EJA cases with (N ≥ 1) or without (N = 0) lymph node metastasis. In particular, CDK6 mutation frequency was expected less, whereas that of LRP1B was remarkably higher in cases with stage N0 than in those with stage N ≥ 1. IHC staining confirmed significant differences in CDK6 and LRP1B expression status between the study and control cohorts. Chi‐square tests revealed that a high CDK6 expression status correlated significantly with smoking history (p = 0.044), T stage (p = 0.035), N stage (p = 0.000), and advanced TNM stage (p = 0.001) in EJA, whereas a high LRP1B expression status only correlated with BMI (p = 0.013) and N stage (p = 0.000). Furthermore, as confirmed by survival status investigation, a high LRP1B expression status predicted good prognosis, and a high CDK6 expression status was an independent predictor of poor prognosis in patients with EJA.

Conclusions

Taken together, the findings of this study demonstrate that a high CDK6 and LRP1B expression status promotes and inhibits lymph node metastasis in patients with EJA, respectively, suggesting that both CDK6 and LRP1B are significantly potential predictors of lymph node metastasis and prognosis in EJA.

Comparison of spectral computed tomography imaging parameters between squamous cell carcinoma and adenocarcinoma at the gastroesophageal junction

OBJECTIVE

To compare the spectral computed tomography (CT) imaging parameters between squamous cell carcinoma (SCC) and adenocarcinoma (AC) at the gastroesophageal junction (GEJ).

METHODS

A total of 80 patients were enrolled in this retrospective study. Among them, 35 were diagnosed with SCC (SCC group) and 45 were diagnosed with AC (AC group). All patients underwent an enhanced scan with spectral CT. The following CT imaging parameters were evaluated: iodine concentration (IC), water content (WC), effective atomic number (Eff-Z) and slope of the spectral HU curve (λHU) of lesions. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of spectral CT imaging parameters for diagnosis of SCC and AC.

RESULTS

Patients with SCC had lower IC, Eff-Z, and λHU in arterial phase and venous phase compared with AC (p< 0.05). There were no significant differences in WC between the two groups. ROC curve analyses revealed that IC, Eff-Z, and λHU in arterial phase and venous phase were predictors for diagnosis of SCC and AC (AUC > 0.5). Moreover, the IC, Eff-Z and λHU in venous phase had better differential diagnostic performances than that in arterial phase.

CONCLUSIONS

Spectral CT could be useful in the differential diagnosis of SCC and AC at the GEJ. Therefore, a routine spectral CT scan is recommended for patients with carcinoma of the GEJ.

Laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy for Siewert type II esophagogastric junction cancer with right aortic arch: a case report

Background

Right aortic arch (RAA) is a congenital malformation detected in 0.04% of the population without heterotaxia and makes esophagectomy and mediastinal lymphadenectomy difficult. A left thoracic approach is recommended in patients with RAA, but a minimally invasive procedure has not yet been established.

Case presentation

The case was a 40-year-old man with RAA and Siewert type II adenocarcinoma of the esophagogastric junction with metastases to the adrenal glands and paraaortic lymph nodes. Conversion surgery was performed when radiologic disappearance of metastatic disease was confirmed after first-line treatment consisting of 12 cycles of S-1 plus platinum-based systemic chemotherapy. Minimally invasive laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy was performed in the right semi-lateral decubitus position. The esophagus was easy to see on left thoracoscopy because of the RAA. Esophagectomy with lower mediastinal lymphadenectomy and an intrathoracic esophagogastric anastomosis was performed successfully with laparoscopy and thoracoscopy without a position change. There were no surgical complications, and no residual cancer was detected in the resected specimen on pathological examination. There has been no recurrence during 21 months of follow-up.

Conclusions

Laparoscopic and left thoracoscopic Ivor-Lewis esophagectomy in the right semi-lateral decubitus position is a minimally invasive, anatomically novel procedure for Siewert type II esophagogastric junction cancer in patients with RAA.

Risk factor of mediastinal lymph node metastasis of Siewert type I and II esophagogastric junction carcinomas

BACKGROUND

Incidence of esophagogastric junction (EGJ) carcinoma has been increasing worldwide. Several studies revealed that the distance from the EGJ to the proximal edge of the primary tumor (esophageal invasion: EI) may be a significant indicator of metastasis in the mediastinal lymph nodes in patients with Siewert type II carcinomas. However, few studies have been conducted in patients with carcinomas located at Siewert type II sequentially to upper carcinomas (Siewert type I) for mediastinal metastasis regardless of histological types.

METHODS

This was a single-center retrospective cohort study. EGJ carcinomas located at Siewert type I and II regions including both squamous cell carcinoma (SCC) and adenocarcinoma were analyzed in terms of lymph node metastasis patterns.

RESULTS

We included 121 patients in this study. Thirty-three (27.3%) patients had SCC. In multivariate analysis, the distance of EI (> 20 mm) was an independent risk factor (OR 11.80, p = 0.005) for lower mediastinal lymph node metastasis. In terms of above the middle mediastinal metastasis, the distance of EI (> 30 m), histological type (SCC), and tumor size (> 40 mm) were risk factors in univariate analysis. Furthermore, EI was significant (OR 13.50, p = 0.026) in multivariate analysis.

CONCLUSIONS

The distance of EI was the independent risk factor for mediastinal lymph node metastasis, especially > 20 mm related with a higher risk for mediastinal lymph node metastasis. Furthermore, EGJ carcinoma patients who have EI > 30 mm, large SCC carcinoma, and multiple lymph node metastasis might be considered the middle-upper mediastinal lymph node dissection by transthoracic approach.

True esophagogastric junction adenocarcinoma: background of its definition and current surgical trends

The definition of true esophagogastric junction (EGJ) adenocarcinoma and its surgical treatment are debatable. We review the basis for the current definition and the Japanese surgical strategy in managing true EGJ adenocarcinoma. The Siewert classification is a well-known anatomical classification system for EGJ adenocarcinomas: type II tumors in the region 1 cm above and 2 cm below the EGJ are described as "true carcinoma of the cardia". Coincidentally, this range matches gastric cardiac gland distribution. Conversely, Nishi's classification is generally used to describe EGJ carcinomas, defined as tumors with the center located within 2 cm above and 2 cm below the EGJ, regardless of their histological subtype. This range coincides with the extent of the lower esophageal sphincter combined with gastric cardiac gland distribution. The current Japanese surgical strategy focuses on the tumor range from the EGJ to the esophagus and stomach. According to previous studies, the strategy can be roughly classified into three types. The optimal surgical procedure for true EGJ adenocarcinoma is controversial. However, an ongoing Japanese nationwide prospective trial will help confirm the appropriate standard surgery, including the optimal extent of lymph node dissection.

Patterns of recurrence in adenocarcinoma of the esophagogastric junction: a retrospective study

Background

The prognosis of adenocarcinoma of the esophagogastric junction (AEG) is poor. Understanding the postoperative recurrence pattern of AEG is helpful to verify the effectiveness of treatment and optimize subsequent treatment, so as to improve prognosis.

Methods

This single-center retrospective study included patients with stage III AEG who underwent surgical treatment between January 2009 and December 2016. According to the different postoperative treatment arm, patients were divided into surgery and surgery plus chemotherapy groups. Recurrence-free survival was used as the outcome to compare the recurrence site and pattern between the groups.

Results

In total, were 306 patients enrolled, 123 in the surgery group and 183 in the surgery plus chemotherapy group. During follow-up (median 17.1 months) of 24 months after surgery, 62.0% of patients had tumor recurrence. The overall recurrence rates in the surgery and surgery plus chemotherapy groups were 86.9% and 77.0%, respectively. The recurrence patterns of both groups were mainly distant metastasis. Postoperative chemotherapy reduced the incidence of hematogenous dissemination from 51.2 to 42.0%. Multivariate Cox analysis showed that the pN stage increased the risk of recurrence, while surgery plus chemotherapy reduced the risk.

Conclusions

Patients with AEG have a risk of hematogenous dissemination after surgery. Postoperative treatment arm and pN stage were independent risk factors in patients with AEG. Surgery plus chemotherapy can improve recurrence-free survival and reduce distant metastasis, but they do not have a beneficial role in controlling local recurrence.

Distribution of lymph node metastases in locally advanced adenocarcinomas of the esophagogastric junction (cT2-4): comparison between Siewert type I and selected Siewert type II tumors

INTRODUCTION

The distribution of lymph node metastases in locally advanced Siewert type I and type II AEG (adenocarcinoma of the esophagogastric junction) remains unclear. The diversity of data in the literature reflects the non-uniformity of tumor stages and surgical procedures in previous studies.

MATERIALS AND METHODS

Based on a retrospective analysis from our single-center database, we examined distributions of lymph node metastases in types I and II cT2-4 AEG. The dataset comprised 44 patients; 19 and 25 patients had type I and type II, respectively. All patients underwent subtotal esophagectomy and total mediastinal lymphadenectomy, which included dissection of the upper mediastinal lymph nodes. The histological data of the surgical specimens were analyzed to evaluate metastasis rates in each lymph node station according to the Japanese Esophageal Society (JES) and American Joint Committee on Cancer (AJCC) guidelines.

RESULTS

Lymph node metastases were observed in 75.0% cases (n = 33/44). There was no significant difference in the total lymph node metastasis rate between the two groups (type I 73.7% versus type II 76.0%). On comparing each lymph node region separately, no statistically significant differences were noted between the groups: upper mediastinal (type I 31.6% versus type II 24.0%), middle and lower mediastinal (type I 31.6% versus type II 44.0%), paragastric (type I 61.1% versus type II 76.0%), and celiac lymph nodes (type I 16.7% versus type II 25.0%).

CONCLUSION

In advanced clinical stages, the metastasis rate is high at all mediastinal lymph node regions in both type I and type II AEGs.

Sites of distant metastases and the cancer-specific survival of metastatic Siewert type II esophagogastric junction adenocarcinoma: a population-based study

BACKGROUND

The effect of distant metastasis on prognosis in patients with Siewert type II adenocarcinoma of the esophagogastric junction (AEG) remains elusive.

METHODS

Patients diagnosed as metastatic Siewert type II AEG were identified using the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier survival analysis and a Cox proportional hazards analysis were performed to assess the effect of distant metastases sites.

RESULTS

We analyzed 1616 eligible patients. Liver was the most frequent metastatic site. For patients with isolated distant metastasis, the median survival time was 8, 7, 8, 10, and 11 months for patients with liver, bone, brain, lung, and distant lymph nodal metastasis, respectively (p = 0.011). The number of metastatic sites and the site of distant metastasis were independent prognostic factors for cancer-specific survival (CSS). In patients with isolated distant metastasis, using bone metastasis as reference, lung (p = 0.011) or distant lymph node metastasis (p = 0.030) was associated with better CSS, while patients with liver (p = 0.051) or brain (p = 0.488) metastasis had similar CSS compared to patients with bone metastasis.

CONCLUSION

CSS in metastatic Siewert type II AEG is dependent on the metastatic site and the number of metastatic sites.

Priority of lymph node dissection for advanced esophagogastric junction adenocarcinoma with the tumor center located below the esophagogastric junction

To clarify the priority of lymph node dissection (LND) in advanced Siewert type II and III AEG, in which the center of the tumor is located below the esophagogastric junction (EGJ).Data in 395 patients with advanced Siewert type II or III AEG was analyzed retrospectively. The index of estimated benefit from LND (IEBLD) was used to evaluate the efficacy of LND for each nodal station.The mean number of dissected LNs did not differ significantly between patients with type II and III AEG, nor did the mean number of retrieved LNs at each station significantly differ between the 2 groups. According to the IEBLD, the dissection of parahiatal LNs (No.19 and 20) and LNs along the distal portion of the stomach (No.5, 6, and 12a) seemed unlikely to be beneficial, whereas the dissection of Nos.1-3, 7, 9 and 11p yielded high therapeutic benefit (IEBLD>3.0) in both groups. The IEBLDs of No.4d, 8a, and 10 were much higher in type III than in type II AEG cases. No.10 LND may improve survival for type III AEG cases (IEBLD = 2.9), especially for subgroups with primary tumors invading the serosa layer, undifferentiated cancers, macroscopic type 3-4 tumors and tumors ≥50 mm in size (all IEBLDs > 4.0).For advanced AEG located below the EGJ, the dissection of paracardial LNs, lesser curvature LNs, and LNs around the celiac axis would promote higher survival benefits regardless of the Siewert subtype. Patients with type III AEG, especially those with serosa-invasive tumors, undifferentiated tumors, macroscopic type 3-4 tumors and tumors ≥50 mm in size may obtain relatively higher survival benefits from No. 10 lymphadenectomy.

Essential updates 2017/2018: Recent topics in the treatment and research of gastric cancer in Japan

Recent developments in diagnostic technology, accumulated clinical effort and established evidence have boosted early detection and drastically improved early and long-term outcomes of gastric cancer. However, gastric cancer continues to be one of the most aggressive and life-threatening malignancies among all cancers and is a global health problem. Between January 2017 and December 2018, various fascinating reports of managements and research were published, including the new 15th Japanese Classification of Gastric Carcinoma reflecting the 8th American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) tumor, node and metastasis (TNM) classification (October 2017) and the new Gastric Cancer Treatment Guidelines version 5 (January 2018). Moreover, pivotal molecular features of gastric cancer were clarified by the worldwide cancer genome project, and various treatment targets and biomarkers such as circulating DNAs and microRNAs were detected. Novel treatment options using programmed cell death protein 1 immune checkpoint inhibitors have been started. In this review, we summarize the recent topics of classification, guidelines, and clinical and basic research in order to bring new insights to gastric cancer treatment.

Current surgical treatment of esophagogastric junction adenocarcinoma

The incidence of esophagogastric junction (EGJ) adenocarcinoma has shown an upward trend over the past several decades worldwide. In this article, we review previous studies and aimed to provide an update on the factors related to the surgical treatment of EGJ adenocarcinoma. The Siewert classification has implications for lymph node spread and is the most commonly used classification. Different types of EGJ cancer have different incidences of mediastinal and abdominal lymph node metastases, and different surgical approaches have unique advantages and disadvantages. Minimally invasive surgeries have been increasingly applied in clinical practice and show comparable oncologic outcomes. Endoscopic resection may be a good therapy for early EGJ cancer. Additionally, there is still a great need for well-designed, large RCTs to forward our knowledge on the surgical treatment of EGJ cancer.

Optimal Extent of Transhiatal Gastrectomy and Lymphadenectomy for the Stomach-Predominant Adenocarcinoma of Esophagogastric Junction: Retrospective Single-Institution Study in China

Background: The optimal extent of gastrectomy and lymphadenectomy for esophagogastric junction (EGJ) cancer is controversial. Our study aimed to compare the long-term survival of transhiatal proximal gastrectomy with extended periproximal lymphadenectomy (THPG with EPL) and transhiatal total gastrectomy with complete perigastric lymphadenectomy (THTG with CPL) for patients with the stomach-predominant EGJ cancer.

Methods: Between January 2004, and August 2015, 306 patients with Siewert II tumors were divided into the THTG group (n = 148) and the THPG group (n = 158). Their long-term survival was compared according to Nishi's classification. The Kaplan–Meier method and Cox proportional hazards models were used for survival analysis.

Results: There were no significant differences between the two groups in the distribution of age, gender, tumor size or Nishi's type (P > 0.05). However, a significant difference was observed in terms of pathological tumor stage (P < 0.05). The 5-year overall survival rates were 62.0% in the THPG group and 59.5% in the THTG group. The hazard ratio for death was 0.455 (95% CI, 0.337 to 0.613; log-rank P < 0.001). Type GE/E = G showed a worse prognosis compared with Type G (P < 0.05). Subgroup analysis stratified by Nishi's classification, Stage IA-IIB and IIIA, and tumor size ≤ 30 mm indicated significant survival advantages for the THPG group (P < 0.05). However, this analysis failed to show a survival benefit in Stage IIIB (P > 0.05).

Conclusions: Nishi's classification is an effective method to clarify the subdivision of Siewert II tumors with a diameter ≤ 40 mm above or below the EGJ. THPG with EPL is an optimal procedure for the patients with the stomach-predominant EGJ tumors ≤30 mm in diameter and in Stage IA-IIIA. For more advanced and larger EGJ tumors, further studies are required to confirm the necessity of THTG with CPL.

Can proximal Gastrectomy Be Justified for Advanced Adenocarcinoma of the Esophagogastric Junction?

Purpose

To evaluate the status of number 3b lymph node (LN) station in patients with adenocarcinoma of the esophagogastric junction (AEG) and to investigate the optimal indications for radical proximal gastrectomy (PG) for AEG.

Materials and Methods

Data of 51 patients with clinically advanced Siewert types II and III AEG who underwent total gastrectomy (TG) between April 2010 and July 2017 were reviewed. The proportion of metastatic LNs at each LN station was examined. Number 3 LN station was separately classified into number 3a and number 3b. The risk factors for number 3b LN metastasis and the clinicopathological features of number 3b-positive AEG patients were investigated.

Results

The incidences of LN metastasis were the highest in number 1 (47.1%), followed by number 2 (23.5%), number 3a (39.2%), and number 7 (23.5%) LN stations. LN metastasis in number 3b LN station was detected in 4 patients (7.8%). A gastric invasion length of more than 40 mm was a significant risk factor for number 3b LN metastasis. All 4 patients with number 3b-positive AEG had advanced cancer with a gastric invasion length of more than 40 mm. The 5-year survival rate of patients with a gastric invasion length of more than 40 mm was 50.0%.

Conclusions

Radical PG may be indicated for patients with AEG with gastric invasion length of less than 40 mm.

Therapeutic Value of Lymph Node Dissection Along the Superior Mesenteric Vein and the Posterior Surface of the Pancreatic Head in Gastric Cancer Located in the Lower Third of the Stomach

Background

Therapeutic value of lymph node dissection along the superior mesenteric vein (14v) and the posterior surface of the pancreatic head (13) remains unclear in gastric cancer patients.

Methods

We reviewed 355 patients with advanced gastric cancer in the lower third of the stomach who had undergone gastrectomy at our hospital.

Results

The frequency of lymph node (LN) metastasis was 10.2% and 7.4% in stations 13 and 14v, respectively. The frequency of station 13 metastasis was 26.8% for T3/T4 tumors with group 2 LNs metastasis and 1.4% for all other tumors. The frequency of station 14v metastasis was 22.2% for T3/T4 tumors with group 2 LNs metastasis and 1.8% for all other tumors. The therapeutic values for dissecting LN stations 13 and 14v were 1.9 and 0.9, respectively, similar to the therapeutic value for group 2 LN dissection.

Conclusion

Because metastasis to stations 13 and 14v occurs frequently in patients with T3/T4 gastric cancer located in the lower third of the stomach who also have metastasis to group 2 LNs, stations 13 and 14v should be dissected in these patients.

Surgical Treatment of Gastroesophageal Junction Cancer

Although the incidence of gastroesophageal junction (GEJ) adenocarcinoma has been increasing worldwide, no standardized surgical strategy for its treatment has been established. This study aimed to provide an update on the surgical treatment of GEJ adenocarcinoma by reviewing previous reports and propose recommended surgical approaches. The Siewert classification is widely used for determining which surgical procedure is used, because previous studies have shown that the pattern of lymph node (LN) metastasis depends on tumor location. In terms of surgical approaches for GEJ adenocarcinoma, a consensus was reached based on two randomized controlled trials. Siewert types I and III are treated as esophageal cancer and gastric cancer, respectively. Although no consensus has been reached regarding the treatment of Siewert type II, several retrospective studies suggested that the optimal treatment strategy includes paraaortic LN dissection. Against this background, a Japanese nationwide prospective trial is being conducted to determine the proportion of LN metastasis in GEJ cancers and to identify the optimal extent of LN dissection in each type.

Prognostic value of the number of negative lymph nodes in esophageal carcinoma without lymphatic metastasis

Background

The impact of the number of negative lymph nodes (LNs) on survival in patients with esophageal cancer remains a controversial issue. This study investigated the association between the number of resected LNs and the prognosis of patients with node‐negative esophageal carcinoma.

Methods

A retrospective review was performed of the data of 429 patients who underwent esophagectomy with modern two‐field lymphadenectomy for the treatment of esophageal cancer between January 1998 and December 2008. Histopathology showed no LN involvement in the patient sample. The prognostic impact of the number of negative LNs and the clinicopathological factors were analyzed.

Results

The overall median survival time and the one, three, and five‐year overall survival rates were 63.0 months and 78.5%, 64.0%, and 51.2%, respectively. Survival analysis confirmed that the number of negative LNs and the depth of tumor invasion were independent prognostic factors. Patients with a high number of negative LNs had a better overall survival rate than patients with a low number of negative LNs (P < 0.001). Patients with dissected LNs > 14 for pT1 tumors (P < 0.001) and > 19 for pT2–3 tumors (P < 0.001 and P = 0.001, respectively) had better long‐term survival outcomes.

Conclusions

The number of negative LNs is an independent prognostic factor for node‐negative esophageal carcinoma. Extended LN dissection is recommended to improve the survival of patients with node‐negative esophageal carcinoma.

Results of a nation-wide retrospective study of lymphadenectomy for esophagogastric junction carcinoma

BACKGROUND

Esophagogastric junction (EGJ) carcinoma has attracted considerable attention because of the marked increase in its incidence globally. However, the optimal extent of esophagogastric resection for this tumor entity remains highly controversial.

METHODS

This was a questionnaire-based national retrospective study undertaken in an attempt to define the optimal extent of lymph node dissection for EGJ cancer. Data from patients with EGJ carcinoma, less than 40 mm in diameter, who underwent R0 resection between January 2001 and December 2010 were reviewed.

RESULTS

Clinical records of 2807 patients without preoperative therapy were included in the analysis. There are distinct disparities in terms of the nodal dissection rate according to histology and the predominant tumor location. Nodal metastases frequently involved the abdominal nodes, especially those at the right and left cardia, lesser curvature and along the left gastric artery. Nodes along the distal portion of the stomach were much less often metastatic, and their dissection seemed unlikely to be beneficial. Lower mediastinal node dissection might contribute to improving survival for patients with esophagus-predominant EGJ cancer. However, due to low dissection rates for nodes of the middle and upper mediastinum, no conclusive result was obtained regarding the optimal extent of nodal dissection in this region.

CONCLUSIONS

Complete nodal clearance along the distal portion of the stomach offers marginal survival benefits for patients with EGJ cancers less than 4 cm in diameter. The optimal extent of esophageal resection and the benefits of mediastinal node dissection remain issues to be addressed in managing patients with esophagus-predominant EGJ cancers.

Laparoscopic lymphadenectomy around the left renal vein (16a2lat) by tunneling under the pancreas for advanced Siewert type II adenocarcinoma

The para-aortic lymph nodes around the left renal vein (16a2lat) are now considered important to target in the treatment of advanced adenocarcinoma of the esophagogastric junction. We describe a laparoscopic approach for resecting these nodes. This new tunneling approach starts from the ligament of Treitz and then enters the retroperitoneal space. The left renal vein and left adrenal vein are dissected to identify the anatomy of the 16a2lat area. After this dissection, the 16a2lat nodes are retrieved through the suprapancreatic area. Six patients with advanced type II junctional cancer underwent laparoscopic 16a2lat lymph node dissection. The median operative time and estimated blood loss were 479 (390-750) min and 250 (130-500) ml, respectively. The median hospital stay was 22 (17-54) days and there were no deaths or serious complications. Although this series was relatively small, our technique proved effective and feasible.