Clinical significance of sentinel node navigation surgery in the treatment of early gastric cancer]

Radical lymphadenectomy is the standard surgical approach even for early-stage gastric cancer with a relatively low incidence of lymph node metastasis because of the limited sensitivity of diagnostic imaging to detect micrometastasis in regional lymph nodes. The sentinel node (SN) concept is one topic among novel diagnostic procedures for micrometastasis. The SN is defined as the first draining node from the primary lesion and it would be the first site of micrometastasis. SN biopsy has been clinically validated and applied for the surgical treatment of malignant melanoma and breast cancer. Although the feasibility of this technique in other solid tumors including gastric cancer is still controversial, there are several reports demonstrating the diagnostic significance of SN mapping in early gastric cancer. We have established radio-guided SN mapping for early gastric cancer, and the diagnostic accuracy using this procedure in cT1N0 cases reached 98%. The radio-guided method allows us to detect the SN in endoscopic surgery quantitatively and reproducibly. Validation of the SN concept in gastric cancer in a multi-centric clinical trial is essential for clinical application of this procedure, including the establishment of a novel, minimally invasive approach for early-stage gastric cancer.     

Sentinel Node Navigation Surgery is Acceptable for Clinical T1 and N0 Esophageal Cancer

Background

If the sentinel node (SN) concept is established for esophageal cancer, it will be possible to reduce safely the extent of lymphadenectomy. Our objective was to perform SN mapping in esophageal cancer to assess distribution of lymph node metastases with the goal to reduce the need for extensive lymphadenectomy.

Methods

A total of 134 patients who underwent esophagectomy with lymph node dissection were enrolled. The number of patients with clinical T1, T2, and T3 tumors was 60, 31, and 32, respectively. Eleven patients also received neoadjuvant chemoradiation therapy (CRT). ^99mTc-Tin colloid was injected endoscopically into the esophageal wall around the tumor 1 day before surgery. SNs were identified by using radioisotope (RI) uptake. RI uptake of all dissected lymph nodes was measured during and after surgery. Lymph node metastases, including micrometastases, were confirmed by hematoxylin eosin and immunohistochemical staining.

Results

Detection rates of SNs were 93.3% in cT1, 100% in cT2, 87.5% in cT3, and 45.5% in CRT patients. In the 120 cases where SNs were identified, lymph node metastases were found in 12 patients with cT1, 18 with cT2, 24 with cT3 tumors, and 3 with CRT. Accuracy rate of SN mapping was 98.2% in cT1, 80.6% in cT2, 60.7% in cT3, and 40% in CRT patients. Although one false-negative case had cT1 tumor, the lymph node metastasis was detected preoperatively.

Conclusions

SN mapping can be applied to patients with cT1 and cN0 esophageal cancer. SN concept might enable to perform less invasive surgery with reduction of lymphadenectomy.

     

Sentinel node micrometastases have high proliferative potential in gastric cancer

BACKGROUND: The 6th edition of the TNM classification has recently defined "sentinel nodes (SN)," "micrometastasis," and "isolated tumor cells (ITC)." The present study examines the frequency and proliferative activity of such metastases with focus on the SNs of gastric cancer. METHODS: We enrolled 133 patients with cT1-2 tumors (cT1: 104, cT2: 29) and mapped SNs. Lymph node metastases were examined by routine histology and by immunohistochemistry with anti-cytokeratin. We used the Ki-67 antibody to detect the primary tumor and lymph node metastases to evaluate proliferative activity. RESULTS: The number of patients with SNs metastases and metastatic SNs was 19 and 52, respectively. The frequencies of macrometastasis, micrometastasis, and ITC were 48%, 25%, and 27%, respectively. Ki-67 expression in the tumor closely correlated with lymphatic invasion (P = 0.0001), venous invasion (P < 0.0001), and lymph node metastasis (P < 0.0001). Cells in 96% of macrometastases, 92% of micrometastases, and 29% of ITCs were Ki-67 positive. CONCLUSIONS: We showed that micrometastasis and some ITCs in SNs had proliferative activity. We suggest that micrometastasis and ITCs should be removed, especially during SN navigation surgery, until their clinical significance is clarified.     

Detection of sentinel node micrometastasis by step section and immunohistochemistry in patients with prostate cancer

PURPOSE: The role of step section and immunohistochemistry for diagnosing sentinel node micrometastases and the sentinel node concept in patients with prostate cancer was investigated. In patients administered neoadjuvant hormone therapy its influence on the sentinel node concept and metastasis diagnosis was also investigated. MATERIALS AND METHODS: Of 62 patients without metastasis enrolled in our study 42 were eligible for analysis. The prostate was injected with the radioactive tracer (99m)technetium phytate 5 to 6 hours before surgery. A planar image and a fusion image with x-ray computerized tomography and single photon emission computerized tomography were obtained 3 hours after tracer injection. Extended lymph node dissection and lymphatic mapping were performed to verify the sentinel node concept. Lymph node metastasis was histologically confirmed by routine hematoxylin and eosin, and thereafter by immunohistochemistry using 250 mum step-sectioned slides. RESULTS: The mean number of dissected lymph nodes was 26.3 per patient. Hot nodes were noted in 41 of 42 patients. The sensitivity and specificity of hot node prediction of lymph node metastasis were 92.3% and 100%, respectively. On routine hematoxylin and eosin examination lymph node metastases were found in 4 of 27 patients with and in 4 of 15 without neoadjuvant hormone therapy. Step section and immunohistochemistry identified micrometastasis in 5 more patients with neoadjuvant hormone therapy. CONCLUSIONS: The validity of the sentinel node concept in conjunction with the detection of micrometastases was considered to be high. Furthermore, it was suggested that the efficacy of metastasis diagnosis may also be enhanced, especially in patients receiving neoadjuvant hormone therapy.     

Detection of sentinel nodes and micrometastases using radioisotope navigation and immunohistochemistry in patients with gastric cancer

BACKGROUND: Patients with early gastric cancer may be treated by minimally invasive surgery. This study investigated the value of sentinel node (SN) navigation surgery, including detection of micrometastases, in patients with clinical (c) T1 and T2 gastric cancer. METHODS: The day before surgery (99m)Tc-radiolabelled tin colloid was injected submucosally near the tumour. After resecting the stomach, radioisotope uptake in all dissected lymph nodes was measured during and after surgery. Micrometastasis was detected immunohistochemically using an anticytokeratin antibody. RESULTS: SNs were identified in 99 of 104 patients. The rate of identification of SNs in patients with cT1 and cT2 tumours, excluding three technical failures, was 99 and 95 per cent respectively. Lymph node metastases and/or micrometastases were found in 28 patients (15 cT1 and 13 cT2). In the 15 patients with cT1 tumours, at least one SN contained metastasis and/or micrometastasis. For cT1 tumours, the sensitivity and accuracy of detecting SNs were both 100 per cent. Six patients with cT2 tumours had false-negative results. CONCLUSION: SN navigation surgery appears to be clinically useful only for cT1 tumours. Based on SN results, the extent of lymphadenectomy may be reduced in patients with early gastric cancer.     

Clinical Implications of Micrometastasis Detection in Internal Mammary Nodes of Breast Cancer Patients

BACKGROUND: The aim of this study was to assess the efficiency of step-serial sectioning (SSS) combined with hematoxylin and eosin (H&E) and immunohistochemical (IHC) staining in detecting micrometastasis of internal mammary lymph nodes (IMLNs). PATIENTS AND METHODS: 135 IMLNs from 88 breast cancer patients were re-examined by SSS, combined with either H&E or IHC staining of the biomarkers cytokeratin-19 and epithelial membrane antigen. RESULTS: Of the 135 IMLNs, 6 nodes from 5 cases displayed 1 or more micrometastases. Histological grade and lymphovascular invasion status were significantly correlated with micrometastasis in the IMLNs (p = 0.018 and 0.001, respectively). Of the 6 nodes positive for micrometastasis, 1 node was detected by both H&E and IHC staining. The remaining 5 nodes from 4 cases showed evident tumor cells only by IHC staining. Finally 8 of the 83 patients (9.64%) without IMLN metastasis showed distant metastasis, while 2 of the 5 patients (40%) with IMLN metastasis showed distant metastasis within 28 months of operation. CONCLUSION: SSS combined with H&E and IHC staining is more efficient in detecting micrometastasis than classic routine single-slice H&E only.     

Laparoscopic sentinel node navigation achieved by infrared ray electronic endoscopy system in patients with gastric cancer

Background The sentinel node (SN) concept has attracted considerable attention recently for the treatment of patients with early gastric cancer (EGC). This study evaluated the feasibility of laparoscopic SN navigation achieved by means of an infrared ray electronic endoscopy (IREE) system with indocyanine green (ICG) injection in patients with EGC. Methods Laparoscopic SN navigation was performed for 16 patients with preoperatively diagnosed EGC. After identification of SNs, routine laparoscopically assisted distal gastrectomy with lymphadenectomy was performed. Lymph nodes were examined histologically for metastasis by hematoxylin and eosin staining on one section of each node. Results One or more SNs and lymphatic basins were detected in all 16 patients. The average number of SNs detected was 2.9. Lymph node metastasis was found in 2 of the 16 patients (13%). In one of these two patients, lymph node metastasis was found in SNs. In the other patient, metastasis was found in a non-SN rather than a SN, but in the same lymphatic basin. The accuracy of this detection method was 94%, and there was one false-negative case. No adverse events occurred after injection of ICG. Conclusion Laparoscopic SN navigation by means of IREE combined with ICG injection is feasible for patients undergoing laparoscopic surgery for EGC.     

Sentinel node biopsy using dye and isotope double tracers in early gastric cancer

Background The results of sentinel node (SN) biopsy have been improved by the use of dye and isotope double tracers in melanoma and breast cancer. However, the usefulness of this double tracer technique has not been determined in gastric cancer. The aim of this study was to investigate the possibility of improving SN biopsy results by using double tracers in gastric cancer.Methods Sixty-four gastric adenocarcinoma patients preoperatively diagnosed as cT1N0, were enrolled in the study. ^99mTc tin colloid was injected by preoperative endoscopy, and lymphoscintigraphy was performed prior to operation. After laparotomy, isosulfan blue was intraoperatively injected using an endoscope. Blue-stained or radioactive nodes were identified and defined as SNs. Gastrectomy with D2 lymphadenectomy was performed in all patients. All dissected lymph nodes were evaluated for metastasis by hematoxylin and eosin staining and immunohistochemistry.Results SN detection rates using dye, isotope, or both tracers were 95.3%, 84.4%, and 96.9%, respectively, and their corresponding sensitivities were 52.9%, 52.9%, and 70.6%. In the pT1 subset, the sensitivity of the double tracer was 87.5%; and in a subset of tumors with diameter <4.5 cm, this was also 87.5%.Conclusions These findings confirm that SN biopsy results are improved by using double tracers in gastric cancer and suggest that SN biopsy is suitable in cases of small-sized early gastric cancer.     

Sentinel Node Metastasis in Patients with Breast Carcinoma Accurately Predicts Immunohistochemically Detectable Nonsentinel Node Metastasis

Background: Sentinel lymphadenectomy is highly accurate for identifying axillary metastasis from a primary breast carcinoma. Nonsentinel axillary lymph nodes (NSNs) are unlikely to contain tumor cells if the axillary sentinel node (SN) is tumor free. We previously showed that the size of the primary tumor and the size of its SN metastasis predict the risk of NSN tumor involvement detected by hematoxylin and eosin staining. This study used immunohistochemical staining (IHC) to determine the likelihood of NSN axillary metastasis in the presence of SN metastasis.Methods: Between 1991 and 1997, axillary lymphadenectomy was performed in 156 women (157 axillary basins) who had primary breast carcinoma with SN metastasis. By hematoxylin and eosin staining, we identified NSN metastasis in 55 axillae (35%). IHC was then used to re-examine all NSNs (1827 lymph nodes) from the remaining 102 axillae. The incidence of IHC-detected NSN involvement was analyzed with respect to clinical and tumor characteristics.Results: By using IHC, we identified NSN metastasis in 15 (14.7%) of the 102 axillae. By multivariate analysis, the size of the SN metastasis (P = .0001) and the size of the primary tumor (P = .038) were the only independent variables predicting NSN metastasis determined by using either hematoxylin and eosin staining or IHC. Only the number of SN metastases (1 vs. >1) was a significant (P = .04) predictor of IHC-detected NSN metastasis.Conclusions: Use of IHC increases the likelihood of detection of NSN metastasis, and the risk of IHC-detected metastasis increases with the size of the SN metastasis and the size of the primary tumor. If SN involvement is micrometastatic (2 mm) or detected by using IHC, tumor cells are unlikely to be found in other axillary lymph nodes in patients with a small primary tumor. The clinical significance of micrometastatic disease in lymph nodes is controversial, and a prospective randomized study is necessary to resolve this important issue.Presented at the 52nd Annual Meeting of the Society of Surgical Oncology, Orlando, FL, March 4–7, 1999.     

Micrometastasis in lymph nodes and microinvasion of the muscularis propria in primary lesions of submucosal gastric cancer

BACKGROUND: It is important to clarify the clinicopathologic characteristics of micrometastasis in lymph nodes and microinvasion in primary lesions for the treatment options with regard to submucosal gastric cancer. METHODS: We examined 1945 lymph nodes and 68 primary tumors resected from 79 patients with submucosal gastric cancer. Two consecutive sections were prepared for simultaneous staining with ordinary hematoxylin and eosin and immunostaining with anticytokeratin antibody (CAM 5.2), respectively. RESULTS: The incidence of nodal involvement in 79 patients with submucosal gastric cancer increased from 13% (10/79 patients) by hematoxylin and eosin staining to 34% (27/79 patients) by cytokeratin immunostaining. Micrometastases in the lymph nodes were found in 17 of 69 patients (25%), with cancer-free nodes examined by hematoxylin and eosin. Microinvasion to the muscularis propria was found in 11 of 68 patients (16%) who were histologically diagnosed with submucosal gastric cancer. Survival analysis demonstrated a lesser 5-year survival in the patients with micrometastasis in lymph nodes (82%) and with microinvasion to muscularis propria (73%). A high incidence of nodal involvement was found in submucosal cancers of large size (> 2 cm; 43%), a depressed type (48%), lymphatic invasion (73%), and deeper submucosal invasion (submucosal 3, 53%). A higher incidence of microinvasion was found with the diffuse-type carcinoma (33%). CONCLUSIONS: Cytokeratin immunostaining is useful for detecting micrometastasis and microinvasion in submucosal gastric cancer. Tumor size, macroscopic type, lymphatic invasion, and the depth of submucosal invasion are strongly associated with lymph node involvement.     

进展期胃癌腹主动脉旁淋巴结微小转移与患者预后的关系

目的研究进展期胃癌腹主动脉旁淋巴结的微小转移对于评价预防性淋巴结清除的意义。方法采用细胞角蛋白抗体,对47例进展期胃癌患者根治性手术清除的2339枚淋巴结(其中包括390枚腹主动旁淋巴结),进行免疫组织化学染色研究。结果常规HE染色发现390枚腹主动脉旁淋巴结中,95枚从14例患者中清除的淋巴结为转移阳性。剩余的295枚淋巴结中,有45枚从另15例患者中清除的淋巴结经免疫组化染色发现有微小转移。术后5年生存率在腹主动脉旁淋巴结转移阴性组为56．0％,微小转移组为25．2％,常规染色淋巴结转移组为9．0％。结论进展期胃癌存在较高的腹主动脉旁淋巴结微小转移率,预防性淋巴结清除对此类患者有效。     

Histopathologic validation of the sentinel lymph node hypothesis for breast carcinoma.

BACKGROUND AND OBJECTIVE: The sentinel node hypothesis assumes that a primary tumor drains to a specific lymph node in the regional lymphatic basin. To determine whether the sentinel node is indeed the node most likely to harbor an axillary metastasis from breast carcinoma, the authors used cytokeratin immunohistochemical staining (IHC) to examine both sentinel and nonsentinel lymph nodes. METHODS: From February 1994 through October 1995, patients with breast cancer were staged with sentinel lymphadenectomy followed by completion level I and II axillary dissection. If the sentinel node was free of metastasis by hematoxylin and eosin staining (H&E), then sentinel and nonsentinel nodes were examined with IHC. RESULTS: The 103 patients had a median age of 55 years and a median tumor size of 1.8 cm (58.3% T1, 39.8% T2, and 1.9% T3). A mean of 2 sentinel (range, 1-8) and 18.9 nonsentinel (range, 7-37) nodes were excised per patient. The H&E identified 33 patients (32%) with a sentinel lymph node metastasis and 70 patients (68%) with tumor-free sentinel nodes. Applying IHC to the 157 tumor-free sentinel nodes in these 70 patients showed an additional 10 tumor-involved nodes, each in a different patient. Thus, 10 (14.3%) of 70 patients who were tumor-free by H&E actually were sentinel node-positive, and the IHC lymph node conversion rate from sentinel node-negative to sentinel node-positive was 6.4% (10/157). Overall, sentinel node metastases were detected in 43 (41.8%) of 103 patients. In the 60 patients whose sentinel nodes were metastasis-free by H&E and IHC, 1087 nonsentinel nodes were examined at 2 levels by IHC and only 1 additional tumor-positive lymph node was identified. Therefore, one H&E sentinel node-negative patient (1.7%) was actually node-positive (p < 0.0001), and the nonsentinel IHC lymph node conversion rate was 0.09% (1/1087; p < 0.0001). CONCLUSIONS: If the sentinel node is tumor-free by both H&E and IHC, then the probability of nonsentinel node involvement is <0.1%. The true false-negative rate of this technique using multiple sections and IHC to examine all nonsentinel nodes for metastasis is 0.97% (1/103) in the authors' hands. The sentinel lymph node is indeed the most likely axillary node to harbor metastatic breast carcinoma.     

Sentinel lymph node mapping for gastric cancer using a dual procedure with dye- and gamma probe-guided techniques

BACKGROUND: Increasing evidence supports the sentinel lymph node (SN) concept for melanoma and breast cancers. SN biopsy may replace routine lymph node dissection in the treatment of these cancers. But there are little data evaluating this concept in patients with gastric cancer. The objective of this study was to test the feasibility of SN mapping in gastric cancers by using the dual-mapping procedure with dye and radioactive colloid. STUDY DESIGN: Thirty-one consecutive patients preoperatively diagnosed as T1-2 and N0 underwent SN biopsy using the dual-mapping procedure. Distributions of SNs identified by the dye-guided technique (blue nodes; BNs) were compared with those identified by the gamma probe guided technique (hot nodes; HNs). RESULTS: Among the 31 patients, 7 were found to have lymph node metastases. All positive nodes were detected by SN biopsy using the dual method. So, an accuracy rate of 100% was achieved in predicting the status of regional lymph nodes. Both BNs and HNs were identified in 28 of 31 patients (90%), but significant discrepancy of distribution was noted between BNs and HNs. Among the 28 patients with identified BNs, there was one metastasis in a non-BN. So the accuracy rate was 96% for the dye-guided technique. In contrast, among the 28 patients with identified HNs, 2 patients had metastasis in non-HNs, making the accuracy rate 93% for the gamma probe-guided technique. CONCLUSIONS: SN mapping is feasible in gastric cancer, but the dye-guided and gamma probe-guided techniques are complementary. So we recommend the dual-mapping procedure.     

Intraoperative sentinel node detection improves nodal staging in invasive bladder cancer

PURPOSE: We evaluated intraoperative SN detection in patients with invasive bladder cancer during radical cystectomy in conjunction with extended lymphadenectomy. MATERIALS AND METHODS: A total of 75 patients with invasive bladder cancer underwent radical cystectomy with extended lymphadenectomy. SNs were identified by preoperative lymphoscintigraphy, intraoperative dynamic lymphoscintigraphy and blue dye detection. An isotope (70 MBq (99m)Tc-nanocolloid) and Patent Blue(R) blue dye were injected peritumorally via a cystoscope. Excised lymph nodes were examined ex vivo using a handheld gamma probe. Identified SNs were evaluated by extended serial sectioning, hematoxylin and eosin staining, and immunohistochemistry. RESULTS: At lymphadenectomy an average of 40 nodes (range 8 to 67) were removed. Of 75 patients 32 (43%) were lymph node positive, of whom 13 (41%) had all lymph node metastases located only outside of the obturator spaces. An SN was identified in 65 of 75 patients (87%). In 7 patients an SN was recognized when the nodal basins were assessed with the gamma probe after lymphadenectomy and cystectomy. Of the 32 lymph node positive cases 26 (81%) had a positive (metastatic) SN. Thus, the false-negative rate was 6 of 32 cases (19%). Five false-negative cases had macrometastases and/or perivesical metastases. In 9 patients (14%) the SN contained micrometastases (less than 2 mm), in 5 of whom the micrometastasis was the only metastatic deposit. CONCLUSIONS: SN detection is feasible in invasive bladder cancer, although the false- negative rate was 19% in this study. Extended serial sectioning and immunohistochemistry revealed micrometastases in SNs in 9 patients and radio guided surgery after the completion of lymphadenectomy identified SNs in an additional 7. We believe that the technique that we used in this study improved nodal staging in these 16 of 65 patients (25%).     

Optimal histopathologic examination of the sentinel lymph node for breast carcinoma staging

Sentinel lymph node dissection is a minimally invasive surgical technique for staging of breast carcinoma. The optimal pathologic examination of the sentinel node (SN) has not yet been determined. Our standard protocol for evaluation of the SN in patients with breast cancer included frozen section at one level, plus paraffin sections at two levels, separated by 40 microm, and stained with hematoxylin and eosin and cytokeratin immunohistochemistry (IHC) at each paraffin section level. In the current study, we evaluated the use of step sections and cytokeratin IHC in 60 SNs (42 consecutive patients) that were tumor-negative on frozen section and hematoxylin and eosin staining at permanent section levels 1 and 2. The SN were reexamined with cytokeratin IHC at eight additional levels (levels 3-10) of the paraffin block, each separated by 40 microm. Previous IHC sections from levels 1 and 2 had shown micrometastases in nine SNs (eight patients) and no tumor cells in the remaining 51 SNs (34 patients). Of the 51 previously negative SNs, only two (4%) SNs from one (3%) patient had metastatic carcinoma cells in levels 3-10. Thus, the additional step sections with cytokeratin IHC did not significantly increase the number of patients with tumor-positive SNs. We currently recommend that the SN be examined with cytokeratin IHC at two levels of the paraffin block. This should optimize sentinel lymph node dissection as a staging technique and minimize the labor and financial burden associated with multiple step sections and IHC stains.     

实时荧光定量PCR检测胃癌淋巴结微转移及其临床意义

目的使用实时荧光定量PCR(qRT-PCR)法检测胃癌淋巴结的微转移情况,并探讨微转移的临床意义。方法收集我院2010年1～6月期间40例行胃癌根治术切除的281枚和10例行胃十二指肠溃疡手术切除的39枚,共计320枚淋巴结标本,以CEA、CK-19和CK-20为引物进行qRT-PCR检测其微转移情况,并分析微转移的临床病理特点。结果 40例胃癌患者中有28例(70.00%)、31枚(15.35%,31/202)淋巴结检测出有微转移。10例胃溃疡的39枚淋巴结标本,HE染色检测和qRT-PCR检测均为阴性。淋巴结微转移的阳性率与肿瘤分化程度、浸润深度和临床分期有关(P<0.05)。结论 qRT-PCR是检测胃癌淋巴结微转移敏感且特异的方法,对胃癌临床分期、判断预后以及治疗方案选择具有重要意义。     

Histopathologic validation of the sentinel node concept in oral and oropharyngeal squamous cell carcinoma

BACKGROUND: In patients with head and neck squamous cell carcinoma (HNSCC), the presence of lymph node metastases is the most important prognosticator. Sentinel node (SN) biopsy has been shown to be an accurate staging technique for patients with breast cancer and melanoma and might also be suited for patients with HNSCC. This study was undertaken to determine whether the SN concept holds true for HNSCC and could be exploited for SN biopsy. METHODS: In 22 patients with T2 to T4 N0 oral or oropharyngeal squamous cell carcinoma (SCC) who were scheduled to undergo combined primary tumor excision and elective unilateral (n = 17) or bilateral (n = 5) neck dissection, SN identification was performed the day before surgery by use of lymphoscintigraphy after peritumoral injections of 99mTc-labeled colloidal albumin. After the neck dissection specimens were removed, all SNs, all other radioactive lymph nodes, and all nonradioactive lymph nodes were retrieved for histopathologic analysis, including serial sectioning at 250-microm intervals and immunohistochemical analysis (IHC). RESULTS: Overall, in 21 (78%) of 27 neck sides, an SN was identified by scintigraphy. Of the six neck sides in which SNs were not identified by scintigraphy, four were from three patients who underwent bilateral neck dissection. In another patient treated by bilateral neck dissection, the SN identified by scintigraphy could not be found in the specimen. In the remaining 20 neck dissection specimens, 23 SNs and 30 additional radioactive lymph nodes could be found. At histologic examination of the 20 neck specimens in which the SN was found, at least one SN was tumor positive in eight cases. In one neck specimen, a metastasis was detected in a nonradioactive lymph node, whereas the SN was tumor free, also at serial sectioning and IHC. In the remaining 11 neck sides in which the SN was tumor negative, none of the other radioactive (n = 13) and none of the nonradioactive (n = 279) lymph nodes contained tumor at histopathologic analysis, including serial sectioning and IHC. The sensitivity of the SN procedure for predicting lymph node metastases, therefore, was 89% (eight of nine neck specimens) when an SN was identified by scintigraphy and found in the specimen. The overall accuracy of the SN procedure for predicting the presence or absence of lymph node metastases in the neck was 95% (19 of 20 neck specimens). CONCLUSIONS: Our study seems to validate the SN hypothesis for oral and oropharyngeal cancer. The role of SN biopsy in the management of the N0 neck in such patients has yet to be established through prospective trials. SN identification (and thus biopsy) does not seem to be reliable in patients with tumors located in or close to the midline.     

检测淋巴结微转移对贲门癌病理分期的意义

目的分析淋巴结微转移在贲门癌病理分期上的临床意义。方法收集2005年1月至2009年12月间海南省农垦总医院行根治性手术的48例PT。N。贲门癌患者临床资料,共获取常规病理学检查阴性的淋巴结323枚。采用免疫组织化学方法,用细胞角蛋白19（CKl9）单抗和CD44v6单抗对淋巴结进行检测,并结合临床病理资料进行统计学分析。结果共9例（18．75％）14枚淋巴结（4．33％）发现微转移。有9例分期得到提高,重新分期率为18．75％。其中IA—IB期1例,IB-ⅡA期3例,ⅡA-ⅡB期3例,ⅡA-ⅢA期1例,ⅡB-ⅢB期1例。微转移组的临床复发率明显高于无微转移组（66．67％vs27．78％,X0=4．752,P=0．029）,5年生存率差异有统计学意义（16．67％vs64．71％,P=0．001）。结论免疫组织化学方法可以提高贲门癌患者淋巴结转移的检出率,有助于更准确地进行临床病理分期。