Impact of total retrieved lymph nodes on staging and survival of patients with gastric cancer invading the subserosa

A novel single-port robot for total gastrectomy to treat gastric cancer: A case report (with video)

Multiport robots are now widely used for total gastrectomy for gastric cancer, while there is almost a void of research on whether single-port (SP) robots can be used for total gastrectomy. Here, we report a case of a 75-year-old female patient who was diagnosed with gastric cardia adenocarcinoma by gastroscopy and underwent total gastrectomy assisted by the SHURUI SP robot. We successfully accomplished total gastrectomy and D2 lymph node dissection using the novel SP robotic platform. The patient was discharged from the hospital successfully with no complications during or after the surgery. Pathologic diagnosis showed adenocarcinoma of the gastric mucosa with partial signet-ring cell carcinoma, and no metastasis was found in the 29 cleared lymph nodes. The use of the SHURUI SP robot for total gastrectomy in treating gastric cancer is both technically feasible and safe.

Extended Lymphadenectomy for Gastric Cancer in the Neoadjuvant Era: Current Status, Clinical Implications and Contentious Issues

Despite its decreasing incidence, gastric cancer remains an important global healthcare problem due to its overall high prevalence and high mortality rate. Since the MAGIC and FNLCC/FFCD trials, the neoadjuvant chemotherapy has been recommended throughout Europe in gastric cancer. Potential benefits of preoperative treatments include a higher rate of R0 resection achieved by downstaging the primary tumor, a likely effect on micrometastases and isolated tumor cells in the lymph nodes, and, as a result, improved cancer-related survival. Nevertheless, distortion of anatomical planes of dissection, interstitial fibrosis, and sclerotic tissue changes may increase surgical difficulty. The collection of at least twenty-five lymph nodes after neoadjuvant therapy would seem to ensure removal of undetectable node metastasis and reduce the likelihood of locoregional recurrence. It is not what you take but what you leave behind that defines survival. Therefore, para-aortic lymph node dissection is safe and effective after neoadjuvant chemotherapy, in both therapeutic and prophylactic settings. In this review, the efficacy of adequate lymph node dissection, also in a neoadjuvant setting, has been investigated in the key studies conducted to date on the topic.

Comparison of the Postoperative Complications Between Robotic Total and Distal Gastrectomies for Gastric Cancer Using Clavien-Dindo Classification: A Propensity Score-matched Retrospective Cohort Study of 726 Patients

BACKGROUND

This study was designed to compare the postoperative complications after Robotic total gastrectomy (RTG) and robotic distal gastrectomy (RDG) and to systematically evaluate the safety and feasibility of RTG for the treatment of gastric cancer (GC).

METHODS

Patients with GC who underwent RTG or RDG for curative intent between March 2010 and August 2019 were analyzed. We used propensity score matching (PSM) to reduce selection bias. The morbidity and mortality within 30 days after surgery between the RTG and the RDG groups were compared.

RESULTS

According to Clavien-Dindo (C-D) classification, the morbidity and mortality of the RTG group were comparable to those of the RDG group. Subgroup analyses showed no significant difference between the RTG and RDG groups in all stratified parameters (all P > .05). Multivariate analysis revealed that age ≥70 years (P = .002) and surgeons' experience ≤25 cases (P = .013) were independent risk factors for overall complication. Surgeons' experience ≤25 cases (P = .010) was identified as an independent risk factor for severe complication.

CONCLUSION

RTG is a safe and feasible surgical procedure for the treatment of GC with acceptable morbidity and mortality. More complications were observed for RTG, indicating that RTG is more invasive than RDG.

Benchmarks for nodal yield and ratio for node-positive gastric cancer

BACKGROUND

We aimed to elucidate prognostic markers of node-positive gastric cancers with a focus on examined lymph nodes and lymph node ratio.

METHODS

Patients treated with curative-intent gastrectomy at The University of Texas MD Anderson Cancer Center from 1995-2019 were evaluated. Patients with non-metastatic, node-positive gastric cancers were considered for analysis.

RESULTS

Of 775 patients, 281 met the inclusion criteria. The mean age was 58 years, 61% were male, 51% were White, 65% received preoperative therapy, and 71% of tumors were located in the gastric body. The median overall survival was 3.6 years, and 1-, 5-, and 10-year overall survival rates were 91%, 41%, and 29%, respectively. pN3 category was associated with worse overall survival (hazard ratio 1.79, P = .001) and recurrence-free survival (hazard ratio 1.92, P = .004). Nodal burden was associated with aggressive biologic traits in primary tumors, including higher rates of lymphovascular and perineural invasion and lower preoperative therapy response rates. By receiver-operative characteristic analysis, threshold values of ≥30 examined lymph nodes and <30% lymph node ratio were most discriminant for overall survival. On adjusted analysis, positive margins, additional organ resection, <30 examined lymph nodes, and ≥30% lymph node ratio were associated with worse recurrence-free survival and overall survival. Among patients with high node burden (pN3), <30 examined lymph nodes remained significant on adjusted survival analysis.

CONCLUSION

Greater than or equal to 30 examined lymph nodes and <30% lymph node ratio were significantly associated with longer recurrence-free survival and overall survival, independent of lymphadenectomy type. These prognostic benchmarks should be considered in the surgical management of gastric cancer in the United States.

Incidence and risk factors of postoperative complications after robotic gastrectomy for gastric cancer: an analysis of 817 cases based on 10-year experience in a large-scale center

BACKGROUND

In this study, we investigated the incidence and risk factors for postoperative complications after robotic gastrectomy (RG) in patients with gastric cancer.

METHODS

A total of 817 patients who underwent RG for gastric cancer between March 2010 and August 2019 were analyzed retrospectively. Postoperative complications were categorized according to the Clavien-Dindo classification, and possible risk factors were evaluated.

RESULTS

Among 817 patients who underwent RG, overall, severe, local and systemic complication rates were 13.8, 4.2, 7.0 and 6.9%, respectively. Multivariable analysis revealed that an age of 70 years or older (P < 0.001) and multiorgan resection (P = 0.031) were independent risk factors for the occurrence of overall complications. Multivariable analysis showed that an age of 70 years or older (P = 0.005) and surgeons' experience ≤ 25 cases (P = 0.004) were independent risk factors for severe complications. Regarding local complications, an age of 70 years or older (P < 0.001), multiorgan resection (P = 0.010) and surgeons' experience ≤ 25 cases (P = 0.005) were identified as independent risk factors. An age of 70 years or older (P < 0.001), a BMI of 25 or higher (P = 0.045) and the presence of comorbidity (P = 0.029) were identified as independent risk factors for systemic complications.

CONCLUSIONS

The present study demonstrated that RG is a safe and feasible procedure for the treatment of gastric cancer, and it has an acceptable postoperative morbidity. Elderly patients and insufficient surgeon experience were two major risk factors for the occurrence of complications following RG. We suggest that surgeons choose patients in good condition during their RG learning phase to reduce learning-associated morbidity.

Adjuvant Chemotherapy vs. Surgery Alone for pT3N0M0 Gastric Cancer

BACKGROUND

As both the role and clinical application of adjuvant chemotherapy (CTx) for pT3N0M0 gastric cancer after curative gastrectomy have fluctuated chronologically, the oncological benefit of adjuvant CTx in patients should be elucidated.

METHODS

Between 2000 and 2018, 1083 patients underwent radical gastrectomy for pT3N0M0 gastric cancer and were subsequently divided into two groups: the surgery-alone group (n = 471) and the adjuvant CTx group (n = 612). Chronological changes in adjuvant CTx and various chemotherapeutic regimens were evaluated and disease-free survival was compared between the two groups. Risk factors for tumor recurrence were also analyzed.

RESULTS

The proportion of patients in the surgery-alone group was more than 60% until 2001, whereas in the CTx group this increased to over 80%, especially after publication of the American Joint Committee on Cancer (AJCC) 7th edition staging manual. The main chemotherapeutic agents were tegafur-uracil (UFT) and 5-fluorouracil with leucovorin until 2008, whereas tegafur/gimeracil/oteracil (TS-1) has been the main agent since 2009. The 5-year disease-free survival was 89.2% in the surgery-alone group and 89.9% in the CTx group, which was not significantly different (p = 0.694). In multivariate analysis, larger tumor size (≥ 4.5 cm) and venous invasion were significant risk factors for tumor recurrence. In addition, adjuvant CTx did not improve the oncological outcome, even in the large tumor size group (p = 0.760) and the venous invasion group (p = 0.753).

CONCLUSIONS

As adjuvant CTx did not show any oncological benefit in pT3N0M0 gastric cancer in this large-scale study, it might be unnecessary for these patients after curative gastrectomy.

Significance of nodal dissection and nodal positivity in gastric cancer

Lymphadenectomy is a central component of surgery for gastric cancer. However, controversies over the optimal extent of lymphadenectomy in gastric cancer surgery have persisted for several decades. In Eastern countries where the incidence of gastric cancer is high, surgeons have performed extensive lymphadenectomy (D2 lymphadenectomy) with low morbidity and mortality, while most Western surgeons have advocated for more limited lymphadenectomies according to the results of Dutch trial and MRC trial. Initially, these trials had failed to show survival benefit of D2 procedure and instead, found pancreaticosplenectomy performed as part of the D2 procedure associated with high incidence of morbidity and mortality. Subsequently, superiority of D2 lymphadenectomy on survival was demonstrated based on updated results. Moreover, spleen and pancreas preserving D2 lymphadenectomy are being performed safely in Western countries. Today, there is an international consensus on performing D2 lymphadenectomy as the standard procedure for advanced gastric cancer and is widely accepted as the standard procedure for gastric cancer surgery. The significance of the extent of lymphadenectomy is intimately associated with the prognostic importance of nodal metastases as the most powerful indicator of recurrence and survival for patients after curative gastrectomy. Maruyama computer program could be used to estimate the risk of lymph node metastasis in each nodal station. The Maruyama Index could be used to assess the adequacy of lymphadenectomy in gastric cancer. Positive lymph node ratio is calculated as the ratio of positive lymph nodes to all harvested lymph nodes, which might be a more precise predictor of prognosis than the absolute number of positive lymph nodes. While D2 lymphadenectomy enables the accurate staging of the disease, reduces the incidence of locoregional recurrences and thus contribute to an improved overall survival; performing lymphadenectomy beyond D2 is unlikely to improve survival. Therapeutic D2+ lymphadenectomy for advanced gastric cancer requires further evaluations, especially for patients receiving neo-adjuvant or conversion treatments.

Intraoperative Surrogate Indicators of Gastric Cancer Patients' Long-Term Prognosis: The Number of Lymph Nodes Examined Relates to the Lymph Node Noncompliance Rate

BACKGROUND

The number of examined lymph nodes (ExLNs) and the rate of lymph node (LN) noncompliance are two independent indicators for evaluating the oncological efficacy for radical gastric cancer (GC) surgery. There are no studies to prove the relationship between these two indicators and their influence on the long-term prognosis of GC patients.

METHODS

The clinicopathological data of 1872 patients with radical GC resection with pathological stage pT2-4N0-3M0 from June 2007 to June 2013 were retrospectively analyzed. Noncompliance was defined as patients with more than one or more LN stations absence as described in the protocol for lymphadenectomy in the Japanese Gastric Cancer Association.

RESULTS

Among 1872 patients, 941 (50.3%) had complete LN compliance, 469 (25.1%) had minor LN noncompliance, and 462 (24.6%) had major LN noncompliance. Logistic regression analysis showed that cT staging and ExLNs were independent risk factors for LN noncompliance. In the whole group, Kaplan-Meier survival curve elucidated that overall survival (OS) differences of ExLNs ≤ 25 and ExLNs > 25 were statistically significant (p < 0.001). Stratified analysis of LN noncompliance elucidated no statistically significant difference in OS of these two group. Multivariate COX regression analysis suggested that LN noncompliance was an independent prognostic factor for OS, whereas ExLNs was no longer an independent prognostic factor for OS.

CONCLUSIONS

The increase number of ExLNs can improve the OS of GC patients, which depends on the decrease of LN noncompliance rate. As surrogate indicators for long-term prognosis of GC patients, LN noncompliance rate was better than ExLNs number.

Effect of lymph nodes count in node-positive gastric cancer

Background: The retrieved lymph node (LN) count has been confirmed as a prognostic indicator in various cancers. However, the correlation between LN counts and patient prognosis in gastric cancer with node-positive is not fully studied.

Methods: A total of 8475 patients undergoing gastrectomy in Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer were analyzed. Kaplan-Meier methods and multivariable Cox regression models were used to analyze long-term outcomes and risk factors. Moreover, nomograms including LN counts were established to predict overall survival (OS) and cancer-specific survival (CSS), and Harrell's concordance index (c-index) was adopted to evaluate prediction accuracy.

Results: Patients were stratified into 1-6, 7-14, and > 14 subgroups according to the optimal cutoff for retrieved LNs in terms of 5-year CSS. Further analysis indicated that higher LN counts were an independent predictor of longer survival in each N category. Nomograms on CSS and OS were established according to all significant factors, and c-indexes were 0.663 and 0.654 (P< 0.001), respectively.

Conclusions: These results indicated that the more the LNs retrieved, the better the survival would be. Nomograms incorporating LN counts can be recommended as practical models to provide more accurate prognostic information for GC patients.

In Patients with Localized and Resectable Gastric Cancer, What is the Optimal Extent of Lymph Node Dissection-D1 Versus D2 Versus D3?

BACKGROUND

Despite advances in the treatment of patients with gastric cancer, the debate over the optimal extent of lymphadenectomy continues.

METHOD

A review of the classification, rationale for, and boundaries of lymphadenectomy is presented. A review of the available literature comparing D1 versus D2 versus D3 lymphadenectomy was performed and included randomized controlled trials, and prospective and retrospective comparative and non-comparative studies.

RESULTS

Earlier studies demonstrated increased morbidity with D2 compared with D1 lymphadenectomy, with no significant survival benefit. More recent studies have demonstrated survival benefit of a pancreas and spleen-sparing D2 lymphadenectomy in patients with advanced, node-positive tumors. Para-aortic/D3 dissections contribute to increased morbidity, with no survival benefit.

CONCLUSIONS

In patients with resectable gastric adenocarcinoma, a D2 lymph node dissection preserving the pancreas and spleen should be considered standard for optimal staging and treatment, provided it is performed by surgeons with sufficient expertise. Extended lymph node dissections beyond D2 should not be routinely performed as it has been shown to have increased morbidity, with no improvement in outcomes. While systemic chemotherapy should be considered standard in patients undergoing D2 lymphadenectomy, the role of adjuvant radiation continues to evolve.

Robot-Assisted Versus Laparoscopy-Assisted Proximal Gastrectomy for Early Gastric Cancer in the Upper Location: Comparison of Oncological Outcomes, Surgical Stress, and Nutritional Status

Background:

An increasing amount of attention has been paid to minimally invasive function-preserving gastrectomy, with an increase in incidence of early gastric cancer in the upper stomach. This study aimed to compare oncological outcomes, surgical stress, and nutritional status between robot-assisted proximal gastrectomy (RAPG) and laparoscopy-assisted proximal gastrectomy (LAPG).

Methods:

Eighty-nine patients were enrolled in this retrospective study between November 2011 and December 2013. Among them, 27 patients underwent RAPG and 62 underwent LAPG. Perioperative parameters, surgical stress, nutritional status, disease-free survival, and overall survival were compared between the 2 groups.

Results:

Sex, age, and comorbidity were similar in the RAPG and LAPG groups. There were also similar perioperative outcomes regarding operation time, complications, and length of hospital stay between the groups. The reflux esophagitis rates following RAPG and LAPG were 18.5% and 14.5%, respectively (P = .842). However, patients in the RAPG group had less blood loss (P = .024), more harvested lymph nodes (P = .021), and higher costs than those in the LAPG group (P < .001). With regard to surgical stress, no significant differences were observed in C-reactive protein concentrations and white blood cell count on postoperative days 1, 3, and 7 between the groups (Ps > .05). There appeared to be higher hemoglobin levels at 6 months (P = .053) and a higher body mass index at 12 months (P = .056) postoperatively in patients in the RAPG group compared with those in the LAPG group, but this difference was not significant. Similar disease-free survival and overall survival rates were observed between the groups.

Conclusions:

RAPG could be an alternative to LAPG for patients with early gastric cancer in the upper stomach with comparable oncological safety and nutritional status. Further well-designed, prospective, large-scale studies are needed to validate these results.

Short-Term Outcomes of Laparoscopic Distal Gastrectomy for Advanced Gastric Cancer

The purpose of this study was to investigate the oncologic outcomes of laparoscopic distal gastrectomy (LDG) for advanced gastric cancer (AGC). Between April 2003 and March 2014, LDG was performed for 392 patients, 91 patients (23.2%) had histopathologically diagnosed AGC beyond T2 depth. The clinicopathological features, postoperative outcomes, mortality, morbidity, recurrence rate, and survivals of those patients were reviewed. The TNM stages of the tumor were IB in 26 patients (28.5%), IIA in 20 (21.9%), IIB in 18 (19.7%), IIIA in 13 (14.2%), IIIB in 6 (6.5%), IIIC in 6 (6.5%), and IV in 2 (2.1%). Major morbidity occurred in 14 patients (15.3%), with no postoperative mortality. Median follow-up was 24.5 months; 10 patients developed recurrence during the follow-up period, and 10 patients died, including 6 cancer deaths. The 5-year overall and disease-free survival rates were 76.8% and 72.6%, respectively. By stage, OS/DFS was 92.3%/91.8% in stage IB, 85.4%/85.4% in stage II, and 49.3%/26.9% in stage III. Oncologic outcomes were good in patients with AGC, especially with stage IB-IIB, who underwent LDG. LDG appears to be an effective approach for treating stage IB and II gastric cancer.

Evaluation of Clavien-Dindo classification in patients undergoing total gastrectomy for gastric cancer

The Clavien-Dindo classification for postoperative complications has been established as a standardized system and applied in many fields of surgery. The aim of our study was to assess the complications after total gastrectomy using the Clavien-Dindo classification and identify risk factors related to them. Four hundred and fifteen patients who underwent total gastrectomy for gastric cancer between April 2009 and September 2014 were enrolled in this study. Postoperative complications were graded, and possible risk factors related to complications were analyzed. The overall complication rate was 13.3 %, with the severe complications classified as grade III or above accounting for 3.1 %. Age of 65 years old or more, higher TNM staging, and open surgery were identified as independent risk factors for overall complications. Age of 65 years old or more, ASA score of 3 or more, multiorgan resection, and retrieved lymph nodes of 30 or more were identified as independent risk factors for severe complications. The Clavien-Dindo system has a broad applicability and facilitates the assessment on the incidence and severity of complications. Large-scaled, prospective clinical trials using the classification are necessary to evaluate the postoperative complications of total gastrectomy for gastric cancer.

Current status of minimally invasive surgery for gastric cancer: A literature review to highlight studies limits

BACKGROUND

Gastric cancer represents a great challenge for health care providers and requires a multidisciplinary approach in which surgery plays the main role. Minimally invasive surgery has been progressively developed, first with the advent of laparoscopy and more recently with the spread of robotic surgery, but a number of issues are currently being investigate, including the limitations in performing effective extended lymph node dissections and, in this context, the real advantages of using robotic systems, the possible role for advanced Gastric Cancer, the reproducibility of completely intracorporeal techniques and the oncological results achievable during follow-up.

METHOD

Searches of MEDLINE, Embase and Cochrane Central Register of Controlled Trials were performed to identify articles published until April 2014 which reported outcomes of surgical treatment for gastric cancer and that used minimally invasive surgical technology. Articles that deal with endoscopic technology were excluded.

RESULTS

A total of 362 articles were evaluated. After the review process, data in 115 articles were analyzed.

CONCLUSION

A multicenter study with a large number of patients is now needed to further investigate the safety and efficacy as well as long-term outcomes of robotic surgery, traditional laparoscopy and the open approach.

State-of-the-art preoperative staging of gastric cancer by MDCT and magnetic resonance imaging

Gastric cancer is one of the most common and fatal cancers. The importance of accurate staging for gastric cancer has become more critical due to the recent introduction of less invasive treatment options, such as endoscopic mucosal resection or laparoscopic surgery. The tumor-node-metastasis staging system is the generally accepted staging system for predicting the prognosis of patients with gastric cancer. Multidetector row computed tomography (MDCT) is a widely accepted imaging modality for the preoperative staging of gastric cancer that can simultaneously assess locoregional staging, including the gastric mass, regional lymph nodes, and distant metastasis. The diagnostic performance of MDCT for T- and N-staging has been improved by the technical development of isotropic imaging and 3D reformation. Although magnetic resonance imaging (MRI) was not previously used to evaluate gastric cancer due to the modality’s limitations, the development of high-speed sequences has made MRI a feasible tool for the staging of gastric cancer.

Robotic gastrectomy versus laparoscopic gastrectomy for gastric cancer: comparison of surgical performance and short-term outcomes

PURPOSE

This study was designed to compare robot-assisted gastrectomy with laparoscopy-assisted gastrectomy in surgical performance and short-term clinical outcomes for gastric cancer and evaluate the safety and feasibility of robotic surgery.

METHODS

A retrospective database of patients who underwent robotic or laparoscopic gastrectomy for gastric cancer between March 2010 and May 2013 was examined. After screening, 514 patients who underwent gastrectomy for gastric cancer were enrolled in this study: 120 robotic and 394 laparoscopic surgery. Patient demographics, surgical performance, and short-term clinical outcomes were examined.

RESULTS

All operations were performed successfully. The clinicopathologic characteristics were similar between the two groups. Compared with the laparoscopic group, the robotic group had less intraoperative blood loss (118.3 ± 55.8 vs. 137.6 ± 61.6 ml, P < 0.001), more lymph nodes dissection (34.6 ± 10.9 vs. 32.7 ± 11.2, P = 0.013), and longer operation time (234.8 ± 42.4 vs. 221.3 ± 44.8 min, P = 0.003). The survival rates were 90.2% at 1 year, 78.1% at 2 years, and 67.8% at 3 years in the RAG group compared with 87.3% at 1 year, 77.1% at 2 years, and 69.9% at 3 years in the LAG group. The difference in overall survival rate between the two groups was not statistically significant (P = 0.812). In view of lymph node involvement, the 3-year survival rates for patients with negative nodal metastasis were 84.4% in the RAG group versus 82.6% in the LAG group (P = 0.972) and 57.5% in the RAG group versus 60.3% in the LADG group (P = 0.653) for those with positive nodal metastasis.

CONCLUSIONS

Comparing well with laparoscopic gastrectomy, robot-assisted gastrectomy is a feasible and safe surgical procedure with clear operation field, precise dissection, minimal trauma, and fast recovery. Longer follow-up time and randomized, clinical trials are needed to evaluate the clinical benefits and long-term oncological outcomes of this new technology.

How many lymph nodes should be assessed in patients with gastric cancer? A systematic review

BACKGROUND

Nodal status is one of the most important prognostic factors in gastric adenocarcinoma (GC). As such, it is important to assess an appropriate number of lymph nodes (LNs) in order to accurately stage patients. However, the number of LNs assessed in each GC case varies, and in many cases the number examined per gastric specimen is less than current recommendations.

PURPOSE

We aimed to identify and synthesize findings from all articles evaluating the association of clinicopathological features and long-term outcomes with the number of LNs assessed among GC patients.

METHODS

Systematic electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1998 to 2009.

RESULTS

Twenty-five articles were included in this review. Extensive resection, increased tumor size, and greater TNM staging were all associated with a greater number of LNs assessed. The disease-free survival was longer and recurrence rate was lower in patients with more LNs assessed. Overall survival, as well as survival by TNM and clinical stage, was improved among patients with an increased number of LNs assessed, but much of this appears to be due to stage migration, with the effect more pronounced in more advanced disease.

CONCLUSION

More LNs assessed resulted in less stage migration and possibly better long-term outcomes. Although current guidelines suggest 16 LNs to be assessed, especially in advanced GC, a higher number of LNs should be assessed.

Reduced lymph node harvest after neoadjuvant chemotherapy in gastric cancer

This retrospective study investigated the impact of neoadjuvant chemotherapy on the number of lymph nodes harvested in patients with T(3)/T(4) gastric cancer. Lymph node counts in 58 patients who received preoperative neoadjuvant chemotherapy were compared with those in 168 patients who received surgery alone. Significantly more patients (n = 14, 24.1%) treated with neoadjuvant chemotherapy had < 15 lymph nodes harvested compared with patients (n = 13, 7.7%) treated with surgery alone. A significant correlation between the total number of harvested lymph nodes and the number of metastatic lymph nodes (mLNs) existed in both groups. Neoadjuvant chemotherapy was the only factor associated with the retrieval of < 15 lymph nodes. The number of mLNs was an independent predictive factor for overall survival. Although neoadjuvant chemotherapy decreased the number of lymph nodes harvested, the number of mLNs may still be an acceptable prognostic factor in patients with gastric cancer, following neoadjuvant chemotherapy.

Clinical implication of an insufficient number of examined lymph nodes after curative resection for gastric cancer

BACKGROUND

The seventh edition of the tumor, lymph node (LN), metastasis (TNM) staging system increased the required number of examined LNs in gastric cancer from 15 to 16. However, the same staging system defines lymph node-negative gastric cancer regardless of the number of examined LNs. In this study, the authors evaluated whether gastric cancer can be staged properly with fewer than 15 examined LNs.

METHODS

The survival rates of 10,010 patients who underwent curative gastrectomy from 1987 to 2007 were analyzed. The patients were divided into 2 groups according to the number of examined LNs, termed the "insufficient" group (≤15 examined LNs) and the "sufficient" group (≥16 examined LNs). The survival curves of patients from both groups were compared according to the seventh edition of the TNM classification.

RESULTS

Three hundred sixteen patients (3.2%) had ≤15 examined LNs for staging after they underwent standard, curative lymphadenectomy. Patients who had T1 tumor classification, N0 lymph node status, and stage I disease with an insufficient number of examined LNs after curative gastrectomy had a significantly worse prognosis than patients who had ≥16 examined LNs. Moreover, having an insufficient number of examined LNs was an independent prognostic factor for patients who had T1, N0, and stage I disease.

CONCLUSIONS

Lymph node-negative cancers in which ≤15 LNs were examined, classified as N0 in the new TNM staging system, could not adequately predict patient survival after curative gastrectomy, especially in patients with early stage gastric cancer.