Nomogram for predicting lymph node metastasis rate of submucosal gastric cancer by analyzing clinicopathological characteristics associated with lymph node metastasis

Background

To combine clinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram.

Methods

We retrospectively analyzed 262 patients with submucosal gastric cancer who underwent D2 gastrectomy between 1996 and 2012. The relationship between lymph node metastasis and clinicopathological features was statistically analyzed. With multivariate logistic regression analysis, we made a nomogram to predict the possibility of lymph node metastasis. Receiver operating characteristic (ROC) analysis was also performed to assess the predictive value of the model. Discrimination and calibration were performed using internal validation.

Results

A total number of 48 (18.3%) patients with submucosal gastric cancer have pathologically lymph node metastasis. For submucosal gastric carcinoma, lymph node metastasis was associated with age, tumor location, macroscopic type, size, differentiation, histology, the existence of ulcer and lymphovascular invasion in univariate analysis (all P<0.05). The multivariate logistic regression analysis identified that age ≤50 years old, macroscopic type III or mixed, undifferentiated type, and presence of lymphovascular invasion were independent risk factors of lymph node metastasis in submucosal gastric cancer (all P<0.05). We constructed a predicting nomogram with all these factors for lymph node metastasis in submucosal gastric cancer with good discrimination [area under the curve (AUC) =0.844]. Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability.

Conclusions

We developed a nomogram to predict the rate of lymph node metastasis for submucosal gastric cancer. With good discrimination and internal validation, the nomogram improved individualized predictions for assisting clinicians to make appropriated treatment decision for submucosal gastric cancer patients.     

Superficial spreading type of early gastric cancer.

To determine the clinicopathological features of the superficial spreading type of early gastric cancer, which is defined as early gastric cancer in which the product of the longest diameter of the tumour and the diameter perpendicular to it is greater than 25 cm2, they were compared retrospectively with those of small-sized early gastric cancers, which are defined as tumours smaller than 2 x 2 cm2. The superficial spreading type accounted for 5.46% of all early gastric cancers. The distinguishing histopathological features of superficial spreading lesions were: a diffuse type of cancer, submucosal invasion and advanced lymph node involvement. Of the 32 patients with superficial spreading lesions, eight underwent an additional resection as a continuance of the first gastrectomy, because of an indistinct tumour margin. More extensive lymph node dissection was also performed on the group with superficial spreading lesions. There was no difference in 5 year survival rate between the two groups (superficial spreading type, 96.0% vs small-sized type, 95.1%). The most appropriate treatment for superficial spreading lesions is a wide surgical resection with extensive lymph node dissection.     

Indications for EMR/ESD in cases of early gastric cancer: relationship between histological type,depth of wall invasion,and lymph node metastasis

Background Limited surgery by endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) for gastric cancer is frequently performed in many institutions. These techniques do preserve gastric function and maintain a high quality of life but may compromise survival. The treatment strategy for early tumors should therefore be based on a complete cure, and limited surgery must thus have clear indications. Methods D2 gastric resection was performed in 278 early gastric adenocarcinomas, and a retrospective histological review of the specimens was made. The extended indications for EMR or ESD, according to the Japanese Gastric Cancer Association Treatment guidelines for gastric cancer in Japan, were also assessed. Results Of the 278 early gastric cancers, 115 were mucosal (M) cancers without ulcer. No lymph node metastases were seen in these specimens. Six of the 41 specimens of M cancer with ulcers had lymph node metastases at the N1 level only. One of these had lymph node metastases from a tumor measuring less than 3 cm in size. Twenty-eight of 122 submucosal cancers had lymph node metastases (23%). Twenty of these were SM1 tumors and 5 had lymph node metastases; 4 of these 5 had lymph node metastases despite the absence of vascular invasion. Conclusion Three cases had lymph node metastases that met the extended criteria for EMR/ESD. EMR and/or ESD should be limited to M cancers without ulcer or differentiated-type M cancer with ulcers smaller than 2 cm. When the depth of tumor invasion is deeper than M, then a gastric resection with lymph node dissection is necessary.     

Expression of pepsinogen II in gastric cancer. Its relationship to local invasion and lymph node metastases

We have determined the prevalence of pepsinogen II (PG II) immunoreactive cells in a large series of early and advanced gastric cancers and relationships among PG II-positivity, tumor histologic type, extent of gastric wall invasion, and presence of lymph node metastases. Of the 316 cancers evaluated, 150 (47%) expressed PG II. The prevalence by histologic type was 55% in 146 glandular tumors, 43% in 83 diffuse tumors, 16% in 25 mucoid tumors, and 51% in 59 mixed-type cancers. Two parietal cell cancers and one undifferentiated cancer were PG II-negative. In glandular and diffuse cancers, but not mucoid and mixed tumors, both the extent of gastric wall invasion and incidence of lymph node metastases were associated positively with PG II expression by the primary tumor. In particular, PG II-reactive cells were found significantly more often in advanced than in early diffuse cancers (P less than 0.05) and significantly more often in submucosal early cancers than in intramucosal early cancers (P less than 0.01). The prevalence of PG II expression also was higher significantly in metastatic cancers than in nonmetastatic cancers. This was true for advanced gastric cancers as a whole (P less than 0.01), advanced glandular-type cancer alone (P less than 0.01), advanced glandular- and diffuse- type cancers together (P less than 0.001), and early diffuse-type cancer (P less than 0.05). Only four (3%) of 145 cancers evaluated for pepsinogen I (PG I) were positive, and each also was positive for PG II. The results suggest that the expression of PG II by glandular and diffuse types of gastric cancer may be a marker of increased malignancy.     

Clinicopathological variables associated with lymph node metastasis in submucosal invasive gastric cancer

Background We aimed to elucidate clinicopathological variables associated with lymph node metastasis of submucosal invasive gastric cancer. Methods Specimens were surgically resected from 201 patients who had primary submucosal gastric cancer. We studied 39 consecutive patients with lymph node metastasis and 162 patients without lymph node metastasis. We compared the following clinicopathological characteristics of the patients in relation to lymph node metastasis: age, sex, tumor size, histology, extent of submucosal invasion, lymphatic and venous invasion, and ulceration of the tumor. Submucosal invasion was divided subjectively into sm1, sm2, and sm3 (representing invasion of the upper-, middle-, and lower-third of the submucosa, respectively). We also studied the relationship between lymph node metastasis of submucosal gastric cancer and immunohistochemistry for p53, Ki67, vascular endothelial growth factor (VEGF), α-fetoprotein, sLe^a, and dendritic cells (DCs). Results In terms of conventional pathological factors, lymph node metastasis in submucosal gastric cancer was related to tumor size (P = 0.002), depth of submucosal invasion (P = 0.001), lymphatic invasion (P < 0.0001), and venous invasion (P = 0.012). Lymph node metastasis in sm1 gastric cancer was significantly related to VEGF expression (P = 0.047). Also, lymph node metastasis in sm3 gastric cancer was significantly correlated with DC expression (P = 0.016). Multivariate analysis showed that tumor size, tumor invasion depth in the submucosal layer, and lymphatic invasion were independent predictors of nodal metastasis in submucosal gastric cancer. Conclusion Conventional pathological factors, such as tumor size, depth of submucosal invasion, and lymphatic invasion, have a significant influence on lymph node metastasis. VEGF expression and DC expression may be helpful predictors of lymph node metastasis in patients with sm1 and sm3 gastric cancer, respectively.     

早期胃癌的淋巴结转移规律及预后分析

目的 分析早期胃癌的临床病理特征与预后之间的关系及早期胃癌的淋巴结转移规律.方法 对1994年1月～2005年10月手术治疗并有完整资料的255例早期胃癌的临床病理学资料进行回顾性分析.结果 255例患者的总5年生存率为91.4%.单因素分析显示,肿瘤浸润深度、脉管瘤栓和区域淋巴结转移与患者术后生存率有关;而性别、年龄...     

Surgical outcome in superficially spreading early gastric cancer

OBJECTIVES: Superficially spreading early gastric cancer is characterized by wide horizontal extension without deep vertical invasion. This study aimed to clarify the clinicopathological characteristics and prognosis of this rare disease. METHODS: We defined superficially spreading early gastric cancer as any tumor invading the submucosal layer that measured > or =60 mm in diameter. The clinicopathological characteristics and results of surgery were compared between 60 patients with superficially spreading tumors and 621 patients with the common type (<60 mm in diameter). RESULTS: For superficially spreading cancers,significantly higher numbers of female patients, undifferentiated and scirrhous types, infiltrating growth and lymph node metastases were seen. The number of metastatic lymph nodes was greater than in the common type. There was no significant difference in the distribution of metastatic lymph nodes between the two groups. For superficially spreading tumors, wide gastrectomy with extended lymph node dissection was frequently employed. Lymph node metastasis, but not tumor diameter, was a prognostic factor in uni- and multivariate analyses. CONCLUSIONS: Although superficially spreading early gastric cancer has histologically distinct properties, gastrectomy with lymph node dissection with sufficient surgical margin could be a suitable treatment.     

Rationale for extensive lymphadenectomy in early gastric carcinoma.

The incidence of nodal metastasis in early gastric carcinoma (EGC) is 10-20%. However, the optimal nodal dissection for early gastric carcinoma has not been established. A retrospective study was conducted in 392 consecutive patients who underwent potentially curative distal gastrectomy for EGC between 1962 and 1990. Of these 295 patients treated after September 1972 were prospectively entered into an extensive lymphadenectomy protocol. These patients were compared with 97 patients with simple gastrectomy in respect of the causes of death after surgery and the 10 year disease-specific survival rate. The incidence of nodal metastasis in early gastric carcinoma patients was 13.0%. Operative mortality from extensive lymphadenectomy was almost the same as from simple gastrectomy (2.0% and 2.1% respectively). Extensive lymphadenectomy provided a significantly higher 10 year survival rate than limited lymph node dissection (97.9% vs 88.1% respectively; P < 0.005). Among patients with nodal metastasis, the survival rate following extensive lymphadenectomy was significantly higher than that after simple gastrectomy (87.5% vs 55.6%; P = 0.018). Among patients without nodal metastasis, there was no difference between the two groups in the survival rate (99.4% and 96.7% respectively; P = 0.12). Multivariate analysis using the Cox proportional hazards model disclosed two significant independent prognostic factors on disease-specific survival, the nodal involvement (risk ratio: 8.4; P < 0.0001) and the extent of lymph node dissection (risk ratio: 5.8; P < 0.005). Extensive nodel dissection appears to prevent recurrence and to improve the cancer-specific survival in EGC patients with nodal metastasis.     

Characteristics of gastric carcinoma invading the muscularis propria

BACKGROUND: Although gastric carcinomas invading the muscularis propria (mp) are classified among advanced-stage cancers in Japan, postoperative survival has been reported to approximate that in early gastric carcinoma. Characteristics of gastric carcinomas invading the mp, therefore, were compared to carcinomas invading only the mucosa (m) or submucosa (sm), and to those invading the subserosa (ss) or serosa (se). METHODS: We retrospectively compared clinicopathologic findings, prognosis, and cause of death in patients with gastric carcinoma invading mp to those showing the other levels of invasion. RESULTS: Patients with carcinomas invading the mp had larger tumors and more frequent lymph node and hematogenous metastases than those with carcinomas invading only m or sm. Yet they had smaller tumors and less frequent lymph node or peritoneal metastasis than those with carcinomas invading ss or se. Postoperative survival with tumors invading the mp was intermediate between that with carcinoma invading only m or sm and that with subserosal or serosal invasion. Causes of death with tumors invading muscularis were similar to those with carcinomas invading only m or sm. CONCLUSIONS: Characteristics of gastric carcinoma invading the mp are intermediate between those of early and advanced carcinoma.     

Clinicopathological features and outcome of surgical treatment of 149 patients with early (pT1) gastric cancer

BACKGROUND: Controversy exists concerning the definition of, treatment approach to, prognostic factors of and survival data on early gastric cancer. PATIENTS AND METHODS: 149 patients who underwent curative gastrectomy for carcinoma between 1972 and 2002 and were classified as having early gastric cancer (T1Nany) were included into a retrospective study. Patients were followed for a median of 5.5 years. RESULTS: We observed an increase in the incidence of early gastric cancer from 7.7% in the 1970s to 22.2% in the 1990s. None of the patients with mucosal tumors had lymph node metastases while 18 (20%) submucosal tumors were node positive. Multivariate analysis of all patients identified depth of tumor infiltration as the only independent risk factor for lymph node metastases. The analysis has shown that none of the clinicopathological features are reliable predictors of nodal status in patients with submucosal invasion. Patients with early gastric cancer had a very good prognosis, 10-year disease-specific survival was 80% or more in all subgroups of patients except for node-positive tumors. Depth of the tumor invasion, lymph node status as well as sex were found to be independent prognostic factors for overall survival. CONCLUSIONS: Early gastric cancer has a very good prognosis after standard surgery. Our data support the use of conservative limited surgical procedures for appropriate patients with mucosal gastric cancer. Patients with submucosal lesions require the same treatment approach as those with more advanced gastric cancer unless clinical usefulness of sentinel lymph node biopsy will be established.     

A case of lymph node metastasis following a curative endoscopic submucosal dissection of an early gastric cancer

Currently in Japan, differentiated gastric submucosal invasive cancers <500 μm (SM1) with negative lymphovascular involvement are included in expanded pathological criteria for curative endoscopic treatment. This is based on a retrospective examination of surgical resection cases in which patients suitable for such expanded criteria were determined to have a negligible risk of lymph node metastasis. We performed endoscopic submucosal dissection on a 65-year-old male with early gastric cancer in April 2005, and pathology revealed a well-differentiated adenocarcinoma, 21 × 10 mm in size, SM1 invasion depth and negative lymphovascular invasion as well as tumor-free margins, so the case was diagnosed as a curative resection. This case, however, resulted in lymph node metastasis that was diagnosed by endoscopic ultrasonography with fine-needle aspiration biopsy in May 2009. Distal gastrectomy with D2 lymph node dissection was then performed, confirming lymph node metastasis from the original gastric cancer.     

早期胃癌淋巴结转移因素分析

目的探讨影响早期胃癌淋巴结转移的因素。方法对74例术后早期胃癌患者的资料,对各临床病理指标与淋巴结转移的关系进行分析,以确定淋巴结转移的危险因素。结果早期胃癌患者的淋巴结转移率为14.9%（11/74）。单因素分析显示黏膜下癌的淋巴结转移率（27.6%）明显高于黏膜内癌（6.7%）（P=0.020）;未分化型癌的淋巴结转移率（27.6%）明显高于分化型（6.8%）（P=0.042）;肿瘤最大径≤2 cm、〉2-4 cm、〉4 cm 3组间淋巴结转移率有统计学意义（χ2=6.549,P=0.038）。采用Log istic回归进行的多因素分析显示,肿瘤最大径（OR=2.688,P=0.047）和浸润深度（OR=4.508,P=0.044）是影响早期胃癌淋巴结转移的独立危险因素。结论早期胃癌淋巴结转移与肿瘤最大径和浸润深度密切相关,这可为手术方案的选择提供参考。     

Clinicopathological characteristics of superficial spreading type early gastric cancer

BACKGROUND AND OBJECTIVES: Superficial spreading type early gastric cancer is characterized by its atypical growth pattern and occasionally indistinct tumor margin. Because it is a rare form of early gastric cancer, the clinicopathological details are not apparent. The aim of this study was to clarify the clinicopathological features of the superficial spreading type of early gastric cancer. METHODS: A retrospective study was conducted in 1,062 surgically resected patients with early gastric cancer. Hospital records were compared between patients with superficial spreading type early gastric cancer and those with more common types of early gastric cancer. RESULTS: Sixty-nine patients (6.9%) had superficial spreading lesions. The male to female ratio was 1.2:1. The most frequent histological type was signet-ring cell carcinoma (32%). The distinguishing histopathological features were submucosal invasion (67%), lymphatic invasion (32%), and lymph node metastasis (30%). There were discrepancies in tumor area between surgical findings and pathological diagnosis in 24 patients (35%) with superficial spreading type. More extensive lymph node dissection was performed and all patients survived in the group with superficial spreading lesions. CONCLUSIONS: The most appropriate treatment for the superficial spreading type of early gastric cancer is wide surgical resection with extensive lymph node dissection.     

Risk of Lymph Node Metastases from Early Gastric Cancer in Relation to Depth of Invasion: Experience in a Single Institution

Background: An accurate assessment of potential lymph node metastasis is important for the appropriate treatment of early gastric cancers. Therefore, this study analyzed predictive factors associated with lymph node metastasis and identified differences between mucosal and submucosal gastric cancers. Materials and Methods: A total of 518 early gastric cancer patients who underwent radical gastrectomy were reviewed in this study. Clinicopathological features were analyzed to identify predictive factors for lymph node metastasis. Results: The rate of lymph node metastasis in early gastric cancer was 15.3% overall, 3.3% for mucosal cancer, and 23.5% for submucosal cancer. Using univariate analysis, risk factors for lymph node metastasis were identified as tumor location, tumor size, depth of tumor invasion, histological type and lymphovascular invasion. Multivariate analysis revealed that tumor size >2 cm, submucosal invasion, undifferentiated tumors and lymphovascular invasion were independent risk factors for lymph node metastasis. When the carcinomas were confined to the mucosal layer, tumor size showed a significant correlation with lymph node metastasis. On the other hand, histological type and lymphovascular invasion were associated with lymph node metastasis in submucosal carcinomas. Conclusions: Tumor size >2 cm, submucosal tumor, undifferentiated tumor and lymphovascular invasion are predictive factors for lymph node metastasis in early gastric cancer. Risk factors are quite different depending on depth of tumor invasion. Endoscopic treatment might be possible in highly selective cases.     

The role of mTOR and phospho-p70S6K in pathogenesis and progression of gastric carcinomas: an immunohistochemical study on tissue microarray

Background

mTOR signaling pathway and its downstream serine/threonine kinase p70S6k were frequently activated in human cancers. The dysregulation of the mTOR pathway has been found to be a contributing factor of a variety of different cancer. To investigate the role of mTOR signal pathway in the stepwise development of gastric carcinomas, we analyzed the correlations between the mTOR and P70S6K expression and clinic pathological factors and studied its prognostic role in gastric carcinomas.

Methods

mTOR and phospho-p70S6K proteins were examined by immunohistochemistry on tissue microarray containing gastric carcinomas (n = 412), adenomas (n = 47) and non-neoplastic mucosa (NNM, n = 197) with a comparison of their expression with clinicopathological parameters of carcinomas.

Results

There was no difference of mTOR expression between these three tissues (p > 0.05). Cytoplasmic phospho(p)-P706SK was highly expressed in adenoma, compared with ANNMs (p < 0.05), whereas its nuclear expression was lower in gastric carcinomas than gastric adenoma and ANNMs (p < 0.05). These three markers were preferably expressed in the older patients with gastric cancer and intestinal-type carcinoma (p < 0.05). mTOR expression was positively correlated with the cytoplasmic and nuclear expression of p-P70S6K(p < 0.05). Nuclear P70S6K was inversely linked to tumor size, depth of invasion, lymph node metastasis and UICC staging (p < 0.05). Univariate analysis indicated that expression of mTOR and nuclear p-P70S6K was closely linked to favorable prognosis of the carcinoma patients (p < 0.05). Multivariate analysis showed that age, depth of invasion, lymphatic invasion, lymph node metastasis, Lauren''s classification and mTOR expression were independent prognostic factors for overall gastric carcinomas (p < 0.05).

Conclusion

Aberrant expression of p-P70S6K possibly contributes to pathogenesis, growth, invasion and metastasis of gastric carcinomas. It was considered as a promising marker to indicate the aggressive behaviors and prognosis of gastric carcinomas.     

未分化型早期胃癌的淋巴结转移规律分析

目的探讨未分化型早期胃癌(EGC)的淋巴结转移规律。方法对1994年1月至2008年12月手术治疗的335例早期胃癌的临床病理学资料进行回顾性分析。结果未分化型早期胃癌的淋巴结转移率为17.9%,其中黏膜内癌(M癌)和黏膜下层癌(SM癌)的淋巴结转移率分别为10.5%、25.6%,直径≤2.0cm和>2.0cm的淋巴结转移率分别为8.0%和25.8%,脉管瘤栓阳性和脉管瘤栓阴性的淋巴结转移率为50.0%和16.3%。单因素分析显示,肿瘤大小、浸润深度、脉管瘤栓与未分化型早期胃癌淋巴结转移相关(P<0.05)。多因素分析显示,肿瘤最大径>2cm、黏膜下层浸润和脉管瘤栓是未分化型早期胃癌淋巴结转移的独立危险因素(P<0.05)。结论肿瘤直径≤2cm、黏膜内癌、无脉管瘤栓的未分化型早期胃癌发生淋巴结转移风险小。     

Application of minimally invasive treatment for early gastric cancer

BACKGROUND AND OBJECTIVES: Although various types of minimally invasive treatment have emerged as the best front-line therapies for early gastric cancer (EGC), there have been no established indications that these attempts are applicable. The purpose of this study was to propose indications for the application of minimally invasive therapy for EGC. METHODS: A total of 566 patients with EGC who had undergone gastrectomy with D2 or more extended lymphadenectomy, from July 1993 to December 1997 were retrospectively analyzed. The risk factors that determine lymph node metastasis were investigated by univariate and multivariate analysis. RESULTS: The rate of lymph node metastasis was 11.8% for all EGC, 3.4% for mucosal cancer, and 21.0% for submucosal cancer. Lymph node metastasis was associated with submucosal invasion, larger tumor size, undifferentiated histology, and the presence of lymphatic or blood vessel invasion (LBVI) by univariate and multivariate analyses. When LBVI was absent, there was no lymph node metastasis if the tumor was smaller than 2.5 cm with differentiated histology, and smaller than 1.5 cm with undifferentiated histology, regardless of depth of invasion. Extra-perigastric lymph node metastases were noted in patients with submucosal tumors that have LBVI while none of mucosal cancer showed extra-perigastric lymph node metastases. CONCLUSIONS: Minimally invasive treatment can be possibly applied for patients with EGC using these four independent risk factors for lymph node metastasis in EGC. For mucosal cancers, EMR is indicated for EGCs without lymph node involvement based on tumor size and histology. When we found LBVI by pathologic examination after EMR, gastrectomy with D1 lymph node dissection is mandatory. For submucosal cancers, patients with small tumors could be treated with laparoscopic wedge resection without lymph node dissection. However, patients with larger sized tumors or tumors with LBVI should be treated with extended (D2) lymph node dissection.     

Prognostic role of lymph node metastasis in early gastric cancer

Objective： To clarify the relationship between clinicopathological features and lymph node metastasis and to propose the potential indications of lymph node metastasis for prognosis in early gaswic cancer （EGC） patients. Methods： We retrospectively observed 226 EGC patients with lymph node resection, and analyzed the associations between lymph node metastasis and clinicopathological parameters using the chi-square test in univariate analysis and logistic regression analysis in multivariate analysis. Overall survival analysis was determined using the Kaplan-Meier and log-rank test. We conducted multivariate prognosis analysis using the Cox proportional hazards model. Results： Of all the EGC patients, 7.5% （17/226） were histologically shown to have lymph node metastasis. The differentiation, lymphovascular invasion and depth of invasion were independent risk factors for lymph node metastasis in EGC. The 5- and 10-year survival rates were significantly lower in patients with lymph node metastasis than in those without and the patients also had shorter progress-free survival time. Lymph node metastasis and tumor size were independent prognostic factors for EGC. The status of the lymph nodes was a significant factor in predicting recurrence or metastasis after surgery. Conclusions： The undifferentiated carcinoma and lymphovascular and/or submucosal invasion were associated with a higher incidence of lymph node metastasis in EGC patients, whom need to perform subsequent D2 lymphadenectomy or laparoscopic lymph node dissection and more rigorous follow-up or additional chemotherapy/radiation after D2 gastrectomy for poor prognosis and high recurrence/metastasis rate.     

215例早期胃癌淋巴结转移的危险因素分析

  目的   探讨早期胃癌淋巴结转移的危险因素。   方法   回顾性分析2005年1月至2010年12月安徽医科大学附属省立医院普外科收治的215例早期胃癌患者的临床病理资料, 并研究早期胃癌淋巴结转移与临床病理因素的关系。   结果   215例患者中淋巴结转移者36例, 单因素分析显示: 肿瘤最大直径(P=0.022)、浸润深度(P=0.003)、Hp感染情况(P=0.004)均与早期胃癌淋巴结转移有关。Logistic多因素回归分析显示: 肿瘤的浸润深度与早期胃癌淋巴结转移有关(P=0.002)。   结论   肿瘤的浸润深度是影响早期胃癌淋巴结转移的独立危险因素。      

Lymph node metastasis risk factors and applicability of endoscopic submucosal dissection in mixed-type early gastric cancer in Chinese patients

BackgroundTo analyze the risk factors of lymph node metastasis (LNM) of mixed-type early gastric cancer (EGC), and to explore whether endoscopic submucosal dissection (ESD) is applicable to mixed-type EGC in Chinese patients.MethodsA total of 812 EGC patients were included. We classified the lesions into four types: pure moderately differentiated (PMD) adenocarcinoma, mixed predominantly moderately differentiated (MMD) type, mixed predominantly poorly differentiated (MPD) type, and pure poorly differentiated (PPD) adenocarcinoma. LNM risk factors in EGC were evaluated by univariate and multivariate analyses, and the feasibility of ESD in mixed-type EGC was estimated.ResultsThe LNM rate in mixed-type EGC was 24.7% (68/275). Tumor size [odds ratio (OR) =1.419, P=0.008], MPD (OR =3.278, P=0.002), submucosal invasion ≥500 µm (OR =5.059, P=0.002), and lymphovascular invasion (LVI) (OR =5.836, P<0.001) were independent predictors of LNM in mixed-type EGC. LNM was more common in MMD patients than in PMD patients who met the expanded indications for ESD of differentiated EGC (0.0% vs. 7.84%, P=0.005).ConclusionsTumor size, histology, invasion depth, and LVI are independent risk factors for LNM in mixed-type EGC. The absolute indications for ESD are applicable to MMD, and the feasibility of the expanded indications for ESD in MMD and MPD requires further investigation in Chinese patients.