Detection of Lymph Node Micrometastases and Isolated Tumor Cells in Sentinel and Nonsentinel Lymph Nodes of Colon Cancer Patients

About 20% to 30% of colon cancer patients classified as node negative by routine hematoxylin-eosin (H&E) staining are found to have micrometastases (MM) or isolated tumor cells (ITC) in sentinel lymph nodes (SLNs) if analyzed by step sections and immunohistochemistry (IHC). Whether SLNs are in this respect representative for all lymph nodes was addressed in this study. SLNs were identified using the intraoperative blue dye detection technique. If all lymph nodes (SLNs and non-SLNs) of a patient were negative by routine H&E staining, they were step-sectioned and analyzed by IHC using pancytokeratin antibodies. We identified at least one SLN in 47 of the 55 patients (85%) and examined a median of 26 lymph nodes per patient (range 10–59). By routine H&E staining, 14 of the 47 patients showed lymph node metastases (30%); the remaining 33 were classified as node-negative. In this group (33 patients), 1011 lymph nodes were analyzed by step sections and IHC: 14 of 70 SLNs. (20%) but only 37 of 941 non-SLNs (4%) had MM/ITC (p < 0.001). Furthermore, 13 of the 33 H&E-negative patients were found to have MM/ITC (39%). In 11 of the 13 patients, MM/ITC were identified in both SLNs and non-SLNs in 1 patient in the SLN only, and in 1 patient in a non-SLN only (sensitivity for the identification of MM/ITC: 92%; negative predictive value: 95%). The SLN biopsy is a valid tool to detect, as well as exclude, the presence of MM/ITC in colon cancer patients. Our results may be of prognostic relevance and influence patient stratification for adjuvant therapy trials.     

Sentinel Node Biopsy in Ductal Carcinoma In Situ Patients

Background: Sentinel lymph node (SLN) mapping is an effective and accurate method of evaluating the regional lymph nodes in breast cancer patients. The SLN is the first node that receives lymphatic drainage from the primary tumor. Patients with micrometastatic disease, previously undetected by routine hematoxylin and eosin (H&E) stains, are now being detected with the new technology of SLN biopsy, followed by a more detailed examination of the SLN that includes serial sectioning and cytokeratin immunohistochemical (CK IHC) staining of the nodes.Methods: At Moffitt Cancer Center, 87 patients with newly diagnosed pure ductal carcinoma in situ (DCIS) lesions were evaluated by using CK IHC staining of the SLN. Patients with any focus of microinvasive disease, detected on diagnostic breast biopsy by routine H&E, were excluded from this study. DCIS patients, with biopsy-proven in situ tumor by routine H&E stains, underwent intraoperative lymphatic mapping, using a combination of vital blue dye and technetium-labeled sulfur colloid. The excised SLNs were examined grossly, by imprint cytology, by standard H&E histology, and by IHC stains for CK. All SLNs that had only CK-positive cells were subsequently confirmed malignant by a more detailed histological examination of the nodes.Results: CK IHC staining was performed on 177 SLNs in 87 DCIS breast cancer patients. Five of the 87 DCIS patients (6%) had positive SLNs. Three of these patients were only CK positive and two were both H&E and CK positive. Therefore, routine H&E staining missed microinvasive disease in three of five DCIS patients with positive SLNs. In addition, DCIS patients with occult micrometastatic disease to the SLN underwent a complete axillary lymph node dissection, and the SLNs were the only nodes found to have metastatic disease. Of interest, four of the five nodepositive patients had comedo carcinoma associated with the DCIS lesion, and one patient had a large 9.5-cm low grade cribriform and micropapillary type of DCIS.Conclusions: This study confirms that lymphatic mapping in breast cancer patients with DCIS lesions is a technically feasible and a highly accurate method of staging patients with undetected micrometastatic disease to the regional lymphatic basin. This procedure can be performed with minimal morbidity, because only one or two SLNs, which are at highest risk for containing metastatic disease, are removed. This allows the pathologist to examine the one or two lymph nodes with greater detail by using serial sectioning and CK IHC staining of the SLNs. Because most patients with DCIS lesions detected by routine H&E stains do not have regional lymph node metastases, these patients can safely avoid the complications associated with a complete axillary lymph node dissection and systemic chemotherapy. However, DCIS patients with occult micrometastases of the regional lymphatic basin can be staged with higher accuracy and treated in a more selective fashion.Presented at the 52nd Annual Meeting of Society of Surgical Oncology, Orlando, Florida, March 4–7, 1999.     

Validation of Ex Vivo Lymphatic Mapping in Hematoxylin-Eosin Node-Negative Carcinoma of the Colon and Rectum

Background: Substantial evidence supports that detailed analysis of the regional lymphatics will identify previously unrecognized micrometastatic disease in colorectal cancer. In order to determine whether the sentinel lymph node(s) (SLNs) harvested by ex vivo lymphatic mapping in node-negative colorectal cancer (CRC) are the most likely node(s) to harbor micrometastatic disease, we examined all nodes in CRC specimens in an identical fashion.Methods: One hundred twenty-four specimens from patients with colorectal cancer were delivered to pathology in the fresh state and underwent ex vivo sentinel lymph node mapping. If negative by routine hematoxylin and eosin (H&E) analysis, the SLNs and non-SLNs were subjected to further analysis by level section H&E and immunohistochemical (IHC) analysis.Results: A mean of 30 nodes were harvested (range, 5–111). Fifty-one patients (41%) were found to be node-positive by routine H&E analysis. SLNs were identified in all but three specimens. A total of 2177 nodes were analyzed from the 66 H&E node-negative specimens (1883 non-SLNs and 294 SLNs). Overall, metastases were identified in 13 of 278 SLNs and in only 5 of 1829 non-SLNs (P < .001). Only 5 of 66 patients (7.5%) had evidence of metastatic disease in non-SLNs when the SLNs were negative. Thirteen apparently node-negative patients (19.3%) were upstaged by IHC analysis of the SLNs (P = .04).Conclusions: If the SLN is negative by both H&E and IHC analysis, the probability of finding metastases in a non-SLN is remote. If microstaging is demonstrated to be prognostically relevant, focused examination should be of the SLN(s).     

Frequency of nonsentinel lymph node metastasis in melanoma

Background Completion lymph node dissection (CLND) may not be necessary for some patients because nodal metastasis is rarely detected beyond the sentinel lymph nodes (SLNs). This analysis was performed to determine, among patients with positive SLNs, the rate of nodal metastasis found in nonsentinel nodes (NSNs). Methods This analysis includes patients with positive sentinel nodes, detected by hematoxylin and eosin (H&E) staining or immunohistochemistry (IHC), who then underwent CLND. Results This analysis included 274 patients with at least one positive SLN who underwent CLND of 282 involved regional nodal basins. Of the 282 SLN-positive nodal basins, 45 (16%) were found to have positive NSNs in the CLND specimen. Breslow thickness. Clark level, presence of ulceration, histological subtype, presence of vertical growth phase, evidence of regression, presence of lymphovascular invasion, number of positive SLNs, age, sex, and presence of multiple draining nodal basins were not predictive of positive nodes in the CLND specimen. Patients with SLN metastases detected only by IHC had an equal likelihood of having positive NSNs as those patients with positive SLNs on H&E examination. Conclusions No patient population could be identified with minimal risk of non-SLN metastasis. When a positive SLN is identified on either H&E staining or IHC, CLND should be performed routinely. Presented at the 54th Annual Cancer Symposium of the Society of Surgical Oncology, Washington, DC, March 15–18, 2001.     

Prospective randomized study comparing sentinel lymph node evaluation with standard pathologic evaluation for the staging of colon carcinoma: results from the United States Military Cancer Institute Clinical Trials Group Study GI-01

BACKGROUND: The principal role of sentinel lymph node (SLN) sampling and ultrastaging in colon cancer is enhanced staging accuracy. The utility of this technique for patients with colon cancer remains controversial. PURPOSE: This multicenter randomized trial was conducted to determine if focused assessment of the SLN with step sectioning and immunohistochemistry (IHC) enhances the ability to stage the regional nodal basin over conventional histopathology in patients with resectable colon cancer. PATIENTS AND METHODS: Between August 2002 and April 2006 we randomly assigned 161 patients with stage I-III colon cancer to standard histopathologic evaluation or SLN mapping (ex vivo, subserosal, peritumoral, 1% isosulfan blue dye) and ultrastaging with pan-cytokeratin IHC in conjunction with standard histopathology. SLN-positive disease was defined as individual tumor cells or cell aggregates identified by hematoxylin and eosin (H&E) and/or IHC. Primary end point was the rate of nodal upstaging. RESULTS: Significant nodal upstaging was identified with SLN ultrastaging (Control vs. SLN: 38.7% vs. 57.3%, P = 0.019). When SLNs with cell aggregates < or =0.2 mm in size were excluded, no statistically significant difference in node-positive rate was apparent between the control and SLN arms (38.7% vs. 39.0%, P = 0.97). However, a 10.7% (6/56) nodal upstaging was identified by evaluation of H&E stained step sections of SLNs among study arm patients who would have otherwise been staged node-negative (N0) by conventional pathologic assessment alone. CONCLUSION: SLN mapping, step sectioning, and immunohistochemistry (IHC) identifies small volume nodal disease and improves staging in patients with resectable colon cancer. A prospective trial is ongoing to determine the clinical significance of colon cancer micrometastasis in sentinel lymph nodes.     

Microstaging of Breast Cancer Patients Using Cytokeratin Staining of the Sentinel Lymph Node

Background: Sentinel lymph node (SLN) mapping is an effective and accurate method of axillary nodal evaluation for metastatic disease. Cytokeratin (CK) immunohistochemical (IHC) staining of the SLN has found micrometastatic disease previously undetected by routine hematoxylin and eosin (H&E) stains. The purpose of this study is to determine the number of patients who were upstaged or microstaged, i.e., detected to have micrometastatic disease only by combined lymphatic mapping with CK IHC.Methods: Two hundred and ten patients with newly diagnosed breast cancer underwent intraoperative lymphatic mapping using a combination of vital blue dye and technetium-labeled sulfur colloid. The excised sentinel lymph nodes were examined grossly, by imprint cytology, by standard H&E histology, and by IHC stains for CK. SLNs that were only CK positive were confirmed to be malignant by histologic examination.Results: CK IHC staining was performed on 381 SLNs in 210 breast cancer patients. Forty-seven of 210 patients (22.4%) had positive nodes. Thirty of these 47 patients (63.8%) had both H&E- and CK-positive SLNs, and an additional 17 of the 47 positive patients (36.2%) had only CK-positive SLNs. Seventeen of the 180 patients (9.4%) who were negative on H&E staining were upstaged by CK IHC staining of malignant cells in the SLN. Comparison of tumor size with the total number of node-positive patients demonstrated that 16 of 30 node-positive T0 and T1 patients (53.5%) and 22 of 39 nodes (56.4%) were upstaged by CK IHC staining. T2 and T3 patients were less frequently upstaged by cytokeratin analysis of lymph nodes. Only one of 17 node-positive patients (5.9%) and seven of 34 nodes (20.6%) in patients with T2 and T3 tumors were upstaged.Conclusion: CK IHC staining of SLNs shifted 9.4% of patients from stage I to stage II. There was a significant upstaging influence noted in patients with tumor sizes under 2 cm. This microstaging shift or upstaging may account for the significant proportion of stage I breast cancer treatment failures. Microstaging of the SLNs using more sensitive assays may help identify a subgroup of patients with invasive breast cancer who would benefit from systemic adjuvant treatment, while sparing a disease-free subset of patients the additional risks of toxic adjuvant chemotherapy.     

Use of sentinel node mapping for cancer of the colon: 'to map or not to map"

Sentinel lymph node (SLN) mapping has become a cornerstone of oncologic surgery because it is a proven method for identifying nodal disease in melanoma and breast cancer. In addition, it can ameliorate the surgical morbidity secondary to lymphadenectomy. However, experience with SLN mapping for carcinoma of the colon and other visceral malignancies is limited. This study represents an update to our initial pilot experience with SLN mapping for carcinoma of the colon. Consenting patients over the age of 18 diagnosed with adenocarcinoma of the colon were included in this study. At the time of operation, 1 to 2 mL of isosulfan blue was injected with a 25-gauge needle into the subserosa at 4 sites around the edge of the palpable tumor. The SLN was identified visually and excised followed by a standard lymphadenectomy and surgical resection. SLNs were evaluated by standard hematoxylin and eosin (H&E) evaluation as well as immunohistochemical (IHC) techniques for carcinoembryonic antigen and cytokeratin if the H&E was negative. Sixty-nine patients underwent SLN mapping. A SLN was identified in 93 per cent (64 of 69) of patients. Nodal metastases were identified in 38 per cent (26 of 69) of patients overall. In 5 patients, the only positive node identified was the SLN, 2 of which were positive by IHC criteria alone. Therefore, 3 per cent (2 of 69) of patients were upstaged by SLN mapping. This technique was 100 per cent specific while being 46 per cent sensitive. Fourteen patients had false-negative SLNs. Metastasis to regional lymph nodes remains the key prognostic factor for colon cancer. SLN mapping is feasible for colon cancer and can identify a subset of patients who could benefit from adjuvant chemotherapy. Although SLN mapping did not alter the surgical management of colon cancer, it does make possible a more focused and cost-effective pathologic evaluation of nodal disease. We do not suggest routine utilization of SLN mapping for colon cancer, but we believe that the data supports proceeding with a national trial.     

The use of cytokeratin staining in sentinel lymph node biopsy for breast cancer.

BACKGROUND: Controversy exists regarding the routine use of cytokeratin immunohistochemistry (IHC) in the histopathologic examination of breast cancer sentinel lymph nodes (SLN) because the clinical significance of micrometastases detected by IHC is unclear. This analysis was performed to determine the frequency of IHC-detected micrometastases. METHODS: All patients underwent SLN biopsy, followed by completion axillary dissection. This analysis included patients who had SLN evaluated by IHC. SLN were examined by hematoxylin and eosin (H&E) stain at 2-mm intervals, with IHC in 2 sections. The axillary dissection specimen was evaluated by routine H&E staining. RESULTS: IHC was performed in SLNs from 973 patients. Of the 869 patients with negative nodes by H&E, 58 (6.7%) were "upstaged" by IHC. In 6 of 58 patients (10.3%) who had IHC-only positive SLN, nodal metastases were found in the axillary dissection specimen. CONCLUSIONS: IHC resulted in upstaging of 6.7% of patients who had negative SLN on H&E staining. These patients had a 10.3% risk of residual axillary nodal metastases. However, the clinical significance of IHC-only positive SLN requires further study.     

Sentinel lymph node positivity of patients with ductal carcinoma in situ or microinvasive breast cancer

PURPOSE: The purpose of this study was to determine the rates of sentinel lymph node (SLN) positivity in patients with a final diagnosis of ductal carcinoma in situ (DCIS) or microinvasive breast cancer (MIC). METHODS: One hundred thirty patients underwent SLN mapping from 1998 to 2003 for DCIS or MIC. RESULTS: One hundred nine patients with DCIS and 21 with MIC underwent SLN mapping. One patient with bilateral DCIS underwent 2 SLN procedures; therefore, the results of 131 SLN procedures are included. On hematoxylin and eosin (H&E) staining, 4 of 110 patients (3.6%) with DCIS had positive SLNs. Four additional patients had positive SLNs by IHC staining only (3.6%). Two of 8 patients underwent completion axillary dissection, and neither had additional involved nodes on completion axillary dissection. One of the 21 patients with MIC had positive SLNs by hematoxylin and eosin (H&E) (4.8%), and another had an involved SLN by IHC staining (4.8%). The patient with the positive SLN by H&E had 1 additional node on completion axillary dissection. CONCLUSION: Rates of SLN positivity for patients with DCIS are modest, even in a high-risk population, and there is continuing uncertainty about its clinical importance.     

Do cytokeratin-positive-only sentinel lymph nodes warrant complete axillary lymph node dissection in patients with invasive breast cancer?

The small number of nodes harvested with lymphatic mapping and sentinel lymph node (SLN) biopsy has allowed a more detailed pathologic examination of those nodes. Immunohistochemical stains for cytokeratin (CK-IHC) have been used in an attempt to minimize the false negative rate for SLN mapping. This study examines the value of CK-IHC positivity in predicting further lymph node involvement in the axillary basin. From April 1998 through May 1999, 519 lymphatic mappings and SLN biopsies were performed for invasive breast cancer. SLNs were examined by imprint cytology, hematoxylin and eosin (H&E), and CK-IHC. Patients with evidence of metastatic disease by any of the above techniques were eligible for complete axillary node dissection (CAND). The frequency with which these modalities predicted further lymph node involvement in the axillary basin was compared. Of the 519 lymphatic mappings, 39 patients (7.5%) had a CK-IHC-positive-only SLN. Five (12.8%) of these 39 patients had at least 2 SLNs positive by CK-IHC. Twenty-six of the CK-IHC-positive-only patients underwent CAND. Three of these 26 patients (11.5%) had additional metastases identified after CAND. The sensitivity levels with which each modality detected further axillary lymph node involvement were as follows: CK-IHC, 98 per cent; H&E, 94 per cent; and imprint cytology, 87 per cent. A logistic regression to compare the prognostic value of the three modalities was performed. All were significant, with odds ratios of 19.1 for CK-IHC (P = 0.015), 5.3 for H&E (P = 0.033), and 3.86 for imprint cytology (P = 0.0059). These data validate the enhanced detection of CK-IHC for the evaluation of SLNs. Detection of CK-IHC-positive SLNs appears to warrant CAND in patients with invasive breast cancer. However, the therapeutic value of CAND or adjuvant therapies based on CK-IHC-positive SLNs would be best answered by prospective randomized trials.     

Does the Method of Biopsy Affect the Incidence of Sentinel Lymph Node Metastases?

More detailed examination of the sentinel lymph node (SLN) in breast cancer has raised concerns about the clinical significance of micrometastases, specifically isolated tumor cells detected only through immunohistochemical (IHC) staining. It has been suggested that these cells do not carry the same biologic implications as true metastatic foci and may represent artifact. A retrospective institutional review board-approved review was conducted on clinically node-negative breast cancer patients who underwent SLN biopsy (SLNB) between 1997 and 2003. Retrospective analysis of tumor characteristics and the method of the initial diagnostic biopsy were correlated with the presence and nature of metastatic disease in the SLN. Of 537 SLNBs, 123 (23%) were hematoxylin-eosin (H&E) positive. SLN positivity strongly correlated with tumor size (p<0.001) and tumor grade (p=0.025), but not with the method of biopsy (needle versus excisional biopsy). Prior to July 2002, we routinely evaluated H&E-negative SLNs with IHC (n=381). Of the 291 H&E-negative patients, 26 had IHC-only detected micrometastases (9%). The likelihood of detecting IHC-only metastases did not correlate with tumor size or grade, but was significantly higher in patients undergoing excisional biopsy than core needle biopsy. While the method of biopsy has no demonstrable effect on the likelihood of finding metastases in the SLN by routine serial sectioning and H&E staining, it may significantly impact the likelihood of finding micrometastases by IHC. IHC should not be used routinely in the evaluation of the SLN and caution should be used when basing treatment decisions (completion axillary lymph node dissection or adjuvant therapy) on IHC-only detected micrometastases.     

Optimal sentinel node examination and a new strategy for axillary control in breast cancer

The sentinel lymph nodes (SLNs) have been reported to reflect the other nodal status in breast cancer, and it is thought that axillary dissection can be avoided in SLN-negative patients, whereas an additional axillary dissection must be performed for SLN-positive patients. To avoid any unnecessary dissection, non–SLN-negative patients should be distinguished among SLN-positive patients. In this study, an optimal histological examination of SLNs was investigated for a precise indication of additional axillary clearance. A modified radical mastectomy with an axillary dissection was performed for 61 patients. Technetium-labeled tin colloids were used to identify the SLNs. In all lymph nodes that were diagnosed as negative at one section by hematoxylin and eosin (H&E) examination, another additional slice was produced for each lymph node. We evaluated how minute areas of cancer in the SLNs can indicate the non-SLNs to be negative. Among 1,092 lymph nodes previously diagnosed by H&E examination as negative at one section, 3 nodes were revealed to be positive in 46 SLNs (6.52%), whereas in additional slices, only 3 nodes out of 1,046 non-SLNs were positive (0.29%). The mean ratio of the cancer cell area to the whole area of SLN on the slice was 15.6% (10–18%) in 12 non–SLN-negative patients and 45.6% (30–83%) in 16 non–SLN-positive patients. It is possible that additional axillary clearance is not needed for patients with a cancer area of less than approximately 20% in the SLN slice, based on an H&E staining evaluation of two slices. SLNs identified with radiolabeled tin colloids could reflect the other nodal status in breast cancer. There is a possibility that additional axillary clearance is not needed for patients with a cancer area of less than approximately 20% in the SLN slice.     

Ex vivo sentinel lymph node mapping in colon cancer: improving the accuracy of pathologic staging?

BACKGROUND: A subset of patients with colon cancer staged by conventional methods have occult micrometastases and do not receive adjuvant chemotherapy. Sentinel lymph node (SLN) mapping and staining by immunohistochemistry is a technique that may identify such occult micrometastases, thereby upstaging patients with positive findings. The purpose of this study was to determine whether ex vivo SLN mapping in colon cancer could be applied successfully to patients at our institution. METHODS: Seventeen patients with intraperitoneal colon tumors undergoing resection were studied prospectively. SLNs were identified as the first blue stained node(s) after ex vivo peritumoral injection of isosulfan blue dye. Additional lymph nodes were harvested and processed in accordance with standard pathologic evaluation for colon cancer. All nodes were examined after routine hematoxylin and eosin (H&E) staining. SLNs that were negative on H&E were analyzed further by multilevel sectioning and immunohistochemistry staining using anticytokeratin monoclonal antibody. RESULTS: Of the 17 study patients, SLNs were identified in 16 (94%) cases. The SLN was the only positive node in 3 patients. An identified SLN was positive (by H&E) in all patients with associated positive non-SLN nodes. The average number of nodes retrieved per patient was 16 (range, 4-54). Overall, SLNs accurately reflected the status of the entire lymph node basin in 16 (94%) patients. Two (12%) patients with negative nodes by H&E potentially were upstaged after further SLN analysis. The negative predictive value for SLN mapping was 89%. CONCLUSIONS: The ex vivo technique of SLN mapping for colon cancer is feasible. In the current study, SLN results were concordant with non-SLNs in the majority of patients. Furthermore, this technique may have upstaged 2 (12%) patients. Whether this ultimately will affect overall survival has yet to be determined.     

Intraoperative sentinel lymph node mapping in stage I non-small cell lung cancer: detection of micrometastases by polymerase chain reaction.

OBJECTIVE: We previously reported the results achieved in detecting sentinel lymph nodes (SLN). We applied the molecular techniques (RT-PCR) to improve the detection of micrometastasis in order to evaluate an improvement of staging in early non-small cell lung cancer (NSCLC) patients (pts). METHODS: This study was carried out on 22 consecutive NSCLC pts with stage I disease. A dose of 37MBq (1 ml (99m)Tc-nanocolloid suspension) was administered. The intralesional injection was performed under CT-guidance (7 pts), by using bronchoscopy (5 pts), VATS (2 pts) and at time of the thoracotomy (8 pts). RT-PCR analysis for cytokeratin 7 and 19 (CK7-CK19) was used to identify tumour-derived material in lymph nodes (LN). Each SLN was bisected: half was used for conventional examination (H&E staining/by immunohistochemistry (IHC), half was snap-frozen to -80 degrees C for RNA-detection of CK7 and CK19. RESULTS: SLN was detected in 16 out of 19 pts. In three pts SLN was not identified (due to an incorrect technique). Conventional pathologic examination showed stage I disease in 13 pts, T3N0 disease in 1 pt, N2 in 5 pts. The IHC analysis identified micrometastasis in seven pts (two evaluated N0 according to H&E staining). RT-PCR analysis, performed in 10/16 pts, identified micrometastasis in 6 pts (3 pts evaluated N0 disease by H&E ; 1 of these evaluated N0 even by IHC). All N2 patients relapsed. One patient (N0 pts after H&E and IHC analysis) with positive CK7 and CK19 expression by RT-PCR analysis relapsed (systemic relapse) 3 months after surgery. CONCLUSIONS: SLN technique could provide a subgroup of patients in which the use of RT-PCR could be applied on a well-focused target. This approach may be useful for stratifying histologically N0 patients into higher risk and lower risk groups.     

The prognostic importance of immunohistochemically detected node metastases in resected esophageal adenocarcinoma

Background

The number or ratio of lymph node metastases detected by hematoxylin & eosin (H&E) staining is the most important predictor of survival in esophageal cancer. The survival effect of lymph node metastases detected on immunohistochemistry (IHC) is controversial. My colleagues and I hypothesized that the extent of nodal disease determined by both H&E and IHC examination would more accurately predict survival than either technique alone.

Methods

The study population consisted of 37 patients who underwent en bloc esophagectomy as primary therapy for esophageal adenocarcinoma 5 or more years ago. All had mediastinal and upper abdominal lymphadenectomy. No patient received neoadjuvant or adjuvant therapy. Tissue blocks were sectioned for H&E staining to confirm the initial histology, and a second slide was stained with monoclonal antibodies AE1 and CAM 5.2, which are directed at a number of cytokeratin antigens. The slides were reviewed by an investigator blinded to clinical outcome. The effect of IHC staining on prognosis was assessed by comparing 5-year survival based on H&E and IHC findings.

Results

A total of 1,970 nodes were examined in the 37 patients. Routine H&E staining detected metastases in 29 patients (78%); the remaining 8 with N0 disease all survived at least 5 years after operation (median not reached). In the 29 patients with N1 disease, survival was 41% at 5 years. In 20 of the 29 N1 patients, metastases were detected by H&E in less than 10% of the nodes removed; 55% of the patients survived 5 years, and 39% survived 8 years. Nine of the 29 patients had metastases detected in more than 10% of the nodes removed, and all died at a median of 17 months. IHC staining was performed on the nodes from the 8 N0 patients and the 20 patients with less than 10% nodal involvement (a total of 28 patients). Additional nodal metastases, not identified on H&E examination, were found in 51 nodes from 17 patients (60.7%). Of the 8 patients who were node negative on H&E examination, 3 had metastases detected by IHC, and all survived 5 years or more free of disease. Of the 20 patients with less than 10% nodal metastases on H&E, 14 (70%) had additional metastases detected by IHC (median, 2 nodes per patient). When combined with the results of H&E staining, the node ratio remained less than 10% in 13 patients and exceeded 10% in 7. Survival in patients whose ratio remained less than 10% was significantly better than in those whose ratio exceeded 10% (actual 5-year survival, 77% vs 14%; χ² = 4.662; p = 0.03).

Conclusions

IHC staining techniques can identify nodal metastases missed by routine H&E examination in a large number of patients. The combination of H&E and IHC examination is useful in patients with less than 10% nodal involvement by H&E examination in that IHC detection of micrometastases allows classification into low-risk (> 75% survival) and high-risk (< 15% survival) groups. IHC-detected micrometastases are not of prognostic importance in N0 patients or those with greater than 10% nodal metastases on H&E.     

Focused examination of sentinel lymph nodes upstages early colorectal carcinoma

Approximately 30 per cent of patients with early colorectal carcinoma (CRC) develop systemic disease. A subgroup of these patients may harbor occult micrometastatic disease and might benefit from adjuvant chemotherapy. We investigated sentinel lymph node (SLN) mapping and focused pathologic examination of the SLN as a means of detecting nodal micrometastases. Between 1996 and 2000 SLN mapping was performed in 50 consecutive patients undergoing colectomy for CRC. All lymph nodes in the resection specimen were examined via routine hematoxylin and eosin (H&E) staining. In addition multiple sections of each SLN were examined via both H&E and cytokeratin immunohistochemistry. At least one SLN was identified in 47 patients (94%). In seven patients (14%) SLN mapping identified aberrant drainage that altered the planned resection. The SLN(s) correctly predicted nodal basin status in 44 of 47 (94%) cases; there were three falsely negative SLNs. Sixteen cases had positive SLNs by conventional H&E staining. An additional 10 (20%) cases were upstaged by a focused examination of the SLNs. Micrometastases were identified in three cases by H&E staining of multiple sections of the SLN and in seven only by cytokeratin immunohistochemistry. In nine cases the SLN was the only node containing tumor cells. In this study, SLN mapping demonstrated aberrant nodal drainage patterns that altered the surgical resection in patients with CRC. Focused examination of SLNs may detect micrometastases missed by conventional techniques and thereby identify patients who might benefit from adjuvant therapy.     

Is breast cancer sentinel lymph node mapping valuable for patients in their seventies and beyond?

BACKGROUND: Axillary lymph node dissection (ALND) is performed less commonly for the axillary staging of elderly patients because it is felt to uncommonly alter therapy. Sentinel lymph node (SLN) dissection can accomplish axillary staging with less morbidity, but it is unclear if it alters subsequent therapy. METHODS: Review of a prospectively collected breast cancer SLN mapping database. Medical records were reviewed to supplement the database. RESULTS: Among 730 breast cancer SLN mapping patients, 261 (35.8%) were >or=70 years of age (range 70 to 95). The overall SLN identification rate was 98.8% among those <70 and 97.1% for those >or=70 (P=.11) and 100% and 99.4%, respectively (P=.25), among the most recent 500 patients. SLN metastases were detected by hematoxalin and eosin staining (H&E) in 24.2% of those <70 and 13.4% of those >/=70 (P<.01) and by immunohistochemistry staining (IHC) only in 4.6% and 5.0% of patients, respectively. No elderly patients with histologically negative SLNs underwent ALND, but 88.9% of patients with H&E metastases and 84.6% with IHC metastases underwent ALND. Of the H&E-positive women, 88% underwent adjuvant systemic therapy versus 55% of H&E-negative women (P<.01). Hormonal therapy was administered to 86.9% of SLN-positive women and 54.3% of SLN-negative women (P<.01) and cytotoxic chemotherapy was administered to 24% of SLN-positive patients versus 2.8% of SLN-negative patients (P<.01). SLN status was associated with significantly different rates of systemic therapy for patients with tumors <1 cm and 1 to 2 cm, but not with tumors >2 cm. Mean follow-up was 15.4 months. No patient experienced local or regional recurrence. Distant metastases occurred in 8.2% of patients with SLN metastases and in no patients with negative SLNs (P<.01). CONCLUSIONS: The results of SLN mapping and biopsy in elderly patients significantly influences subsequent therapy decisions, including ALND, hormonal therapy, and cytotoxic chemotherapy. SLN biopsy should be recommended to elderly breast cancer patients.     

Infrared ray electronic endoscopy combined with indocyanine green injection for detection of sentinel nodes of patients with gastric cancer

BACKGROUND: To avoid unnecessary lymphadenectomy in patients with cancer accurate diagnosis of the sentinel lymph node (SLN) is important. METHODS: This report examined the initial clinical use of infrared ray electronic endoscopy (IREE) combined with indocyanine green (ICG) injection for SLN detection in 84 patients with gastric cancer not invading the subserosa (75 T1 N0 M0 and nine T2 N0 M0 tumours, according to tumour node metastasis classification). RESULTS: There were no adverse events after injection of ICG. At least one SLN was detected in all but one patient by both ICG injection alone and by IREE with ICG. Eleven of the 84 patients had lymph node metastasis. SLNs detected by ICG injection alone did not include metastases in four of 11 patients, whereas IREE with ICG detected SLNs containing lymph node metastases in all 11 patients. Moreover, SLNs illuminated by IREE with ICG included all metastases among the 105 regional lymph nodes in the 11 patients; no metastatic lymph nodes were identified among 154 non-SLNs. CONCLUSION: IREE combined with ICG injection may efficiently detect SLNs that contain metastases in patients with gastric cancer.     

结直肠癌前哨淋巴结体外亚甲蓝染色的临床研究

目的探讨用体外亚甲蓝作为染色剂寻找前哨淋巴结(sentinel lymph node,SLN)的方法在结直肠癌SLN定位中的临床价值。方法将根治性切除大肠癌标本,在肿块四周浆膜下注射亚甲蓝后常规固定送病理检查。蓝染的淋巴结视为SLN。结果67例患者中找到SLN的有63例(91.3%),SLN镜下转移14例(22.22%)。结肠的SLN转移阳性的诊断价值与非SLN相比差异有统计学意义(P=0.0005),但在直肠癌中SLN转移阳性的诊断价值与非SLN相比差异无统计学意义(P=0.60),且SLN转移阳性在结肠癌病例中假阴性率为11.11%,而在直肠癌病例中则高达42.86%。结论体外亚甲蓝染色寻找SLN的方法在结肠癌中的应用是有效、可靠的,但在直肠癌中的应用其可靠性值得进一步的研究。