Morphological Distribution of Metastatic Foci in Sentinel Lymph Nodes with Gastric Cancer

Background The TNM classification defines micrometastasis (MM) and isolated tumor cells (ITC) in lymph nodes (LN). Sentinel node (SN) navigation surgery has been introduced in gastrointestinal cancer. Few reports have examined the morphological distribution of MM and ITC of SN in gastric cancer. The purpose of this study was to clarify the clinical significance of the morphological distribution of cancer cells in SNs according to metastasis (MA), MM, and ITC. Methods All dissected LNs obtained from 160 consecutive patients with mapped SNs arising from cT1–2 N0 tumors were examined. Metastasis in these LNs was examined by histology and cytokeratin staining. The distribution of MA, MM, and ITC was classified as marginal sinus (MS), intermediate sinus (IS), parenchymal (PA), and diffuse types (DF). Results Nodal metastases were detected in 65 SNs from 30 patients and MA, MM, and ITC accounted for 53.9%, 21.5%, and 24.6%, respectively. MS, IS, PA, and DF accounted for 57%, 6%, 17%, and 20.0%, respectively. Patients with metastasis of non-MS had more nodal metastasis in non-SNs (P = .025) and had nodal metastasis in second tier (P = .009), compared with the patients with metastasis of MS. The incidence of metastasis in non-MS was higher in tumors larger than 40 mm than those smaller than 40 mm (P = .011). Conclusion When performing SN navigation surgery in gastric cancer, we should keep in mind that the patients with tumor larger than 40 mm in size and nodal metastasis of non-MS may have non-SN metastasis and nodal metastasis in second tier.     

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.

     

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.     

Isolated Tumor Cells in the Sentinel Node Affect Long-Term Prognosis of Patients with Melanoma

Background The clinical significance of isolated tumor cells (ITCs) in the melanoma-draining sentinel nodes (SNs) is unclear. Methods Records of patients who underwent SN biopsy (SNB) for stage I/II melanoma at our institute between 1991 and 2003 were reviewed to identify patients whose SNs were tumor-free or contained only ITC (≤0.2 mm). Tumor-positive SNs were reevaluated by the study pathologist to confirm the diagnosis and microstage the SN. Characteristics of the primary melanoma, tumor status of regional lymph nodes, and other prognostic variables were recorded. Melanoma-specific survival (MSS) rates were compared by the log-rank test. Results Of 1382 patients who underwent SNB, 1168 (85%) had tumor-free SNs; among the 214 remaining patients with tumor-positive SNs, 57 had metastases limited to ITC. Completion lymphadenectomy (CLND) was performed in 52 of 57 patients: six (12%) had metastases in nonsentinel nodes (NSNs). At a median follow-up of 57 months, 5-year and 10-year MSS was significantly higher (P = .02) for the 1168 patients with tumor-negative SNs (94 ± 1% and 87 ± 2%, respectively) than the 57 patients with ITC-positive SNs (89 ± 4% and 80 ± 7%, respectively). Multivariate analysis identified ITC (P = .002), Breslow’s thickness (P < .0001), ulceration (P < .0001), and primary site (P = .04) as significant for MSS. Conclusion Patients with ITC in SNs have a significantly higher risk of melanoma-specific death than those with tumor-negative SNs. The 12% incidence of nonsentinel node metastasis is similar to rates reported for patients with more extensive SN involvement. Patients with ITC should be considered for CLND. Presented at the annual meeting of the Society of Surgical Oncology, March 15–18, 2007, Washington, DC.     

Predictive factors for metastatic involvement of nonsentinel nodes in patients with breast cancer

BACKGROUND: The potential morbidity of an axillary lymph node dissection in patients with breast cancer can be avoided in patients with a negative sentinel node (SN). HYPOTHESIS: It may be possible to identify a subset of patients with a positive SN and without metastases in the remaining axillary lymph nodes. DESIGN: Case-control study. SETTING: Both primary and referral hospital care. PATIENTS: Data were studied for 255 consecutive patients with stage T1 or T2 breast cancer who had a successful identification of the SN. INTERVENTIONS: In patients with a positive SN, histological examination of all non-SNs that were negative by routine examination was the same as that for SNs (multiple sectioning and immunohistochemical analysis). MAIN OUTCOME MEASURES: The incidence of non-SN metastases was correlated with the surface area and number of SN metastases and primary tumor characteristics. A micrometastasis was defined as less than 1 mm(2). RESULTS: Of 255 patients, the SN appeared to be positive in 93 (36%). Subsequent axillary lymph node dissection revealed positive non-SNs in 46 patients (49%). Patients with a single positive SN and patients with metastases less than 1 mm(2) in the SN had significantly less non-SN involvement than patients with more than 1 positive SN (40% vs. 78%) and patients with macrometastases (27% vs. 49%). CONCLUSIONS: The incidence of non-SN metastases seemed to be related to the number of positive SNs and the size of SN metastases. However, in the group of patients with a positive SN, it was not possible to identify a subset of patients without non-SN metastases.     

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%).     

A Simple Nomogram to Evaluate the Risk of Nonsentinel Node Metastases in Breast Cancer Patients with Minimal Sentinel Node Involvement

Background  

Tumor-positive sentinel node biopsy (SNB) suggests a risk of nonsentinel node metastases in breast cancer. This risk is lower after micrometastasis or isolated tumor cells (ITC) in the sentinel node (SN), and recent studies suggest that completion axillary lymph node dissection (ALND) might not improve outcome in these patients. We aim to validate existing predictive models and to develop a new model for micrometastatic and ITC patients.     

Lymph Node Tumor Volumes in Patients Undergoing Sentinel Lymph Node Biopsy for Cutaneous Melanoma

Background: Regional lymph node tumor volumes in patients undergoing sentinel lymph node (SN) biopsy (SNB) for treatment of cutaneous melanoma have not been described. The objectives of this study were to describe the lymph node tumor volumes typically seen in this population and to correlate tumor volumes with tumor thickness and positive SN characteristics.Methods: Review of a consecutive series of patients with clinically localized cutaneous melanoma who underwent SNB of nonpalpable regional lymph node basins followed by complete lymphadenectomy (LND) was performed. Multiple lymph node sections from positive SNs and nonsentinel nodes (NSNs) in LND specimens were examined microscopically. Individual tumor deposit diameters were measured using an ocular micrometer. Aggregate tumor volumes were calculated for SN and LND specimens. Tumor volumes and SN and LND positivity rates were correlated with tumor thickness, the number of positive SNs, and the presence of multiple SN tumor deposits.Results: SNB procedures were performed for 149 melanomas in 189 regional nodal basins. The mean tumor depth was 2.48 mm. The mean number of SNs/basin was 2.1. Thirty-two of 149 SNB procedures (21.5%) revealed a total of 34 nodal basins with at least one positive SN. The median tumor volume in positive SNs was 4.7 mm³ (range, 0.1-3618 mm³; mean, 209 mm³). The median aggregate tumor volume in positive LND specimens was 4.9 mm³ (range, 0.1-3618 mm³; mean, 224 mm³). Six basins (17.6%) contained at least one positive NSN. The regional node aggregate tumor volume correlated weakly with tumor thickness (Pearsons correlation coefficient = .302, P = .0934). NSN positivity was not predicted by tumor thickness, American Joint Committee on Cancer tumor stage, number of positive SNs, or number of metastatic deposits within SNs.Conclusions: Most melanoma-positive SNs contain minute tumor volumes. Tumor thickness and patterns of SN metastases may not be predictive of tumor burden or the presence of positive NSNs.     

Risk factors of sentinel and non-sentinel lymph node metastases in patients with ductal carcinoma in situ of the breast: A nationwide study

ObjectivesUnexplained axillary metastases have been detected in some patients with ductal carcinoma in situ (DCIS), possibly because of occult invasion or iatrogenic tumor cell displacement. The significance of these metastases is unknown and brings into questions the need for upstaging and axillary surgery. What are the risk factors for sentinel lymph node (SN) and non-SN metastases, including the risk of iatrogenic displacement of tumor cells in relation to an excisional biopsy, in patients diagnosed with DCIS?MethodsNationwide data on 1787 women diagnosed with DCIS between 2001 and 2015 were retrieved from the Danish Breast Cancer Group database. The association of clinicopathological variables with a positive SN (isolated tumor cells (ITCs), micro- or macrometastases) was evaluated using univariate and multivariate analyses.ResultsOf the 1787 patients, 71 (4.0%) had a positive SN: 15 (0.8%) had macrometastases, 42 (2.4%) had micrometastases, and 14 (0.8%) had ITCs. Five patients with a positive SN also had a positive non-SN. In adjusted analysis, a positive SN was associated with younger age (P = 0.036), increased size (P = 0.002), palpability (P = 0.0004) and surgical excisional biopsy (P < 0.001).ConclusionsThe overall risk of a positive SN in patients with DCIS on final pathology is low and less than 9% of these patients had positive non-SNs. This argues against using axillary lymph node dissection in this group. The odds of positive SN after surgical excisional biopsies showed more than a four-fold increase, indicating iatrogenic tumor cell displacement. It is questioned whether these patients should be upstaged and classified as having invasive carcinoma.     

Utility and pitfalls of sentinel node identification using indocyanine green during segmentectomy for cT1N0M0 non-small cell lung cancer

Purposes

Sentinel node identification using indocyanine green (ICG) is not only simpler, but also more cost-effective, than using radioisotope tracers. We herein examined the utility and pitfalls of sentinel node (SN) identification using ICG during segmentectomy in patients with cT1N0M0 non-small cell lung cancer (NSCLC).

Methods

ICG was injected around the tumor after thoracotomy, followed by segmentectomy and lymph node dissection, in 135 patients with cT1N0M0 NSCLC. The dissected nodes were examined using an ICG fluorescence imaging system.

Results

SNs could be identified in 113 patients (84 %). The mean number of SNs was 2.3 ± 1.3. The percentages of being an SN were 57 % for both stations #12 and #13, which was significantly higher than the 18 % for #10 and 22 % for #11 (p < 0.001). Fourteen patients had N1 or N2 disease. Of these, the SNs were true positive (i.e., SNs contained metastasis) in 11 patients (79 %) and false negative (i.e., SNs did not contain metastasis, while non-SNs contained metastasis) in three patients (21 %). Of the three patients with false-negative results, all non-SNs containing metastases were at station #12 or #13.

Conclusion

While ICG makes it simple to identify SNs during segmentectomy for cT1N0M0 NSCLC, stations #12 and #13 should be submitted for frozen sections along with the identified SNs to avoid missing true SNs.

     

Sentinel Node Mapping in Adenocarcinoma of the Esophagogastric Junction

Background

The incidence of adenocarcinoma of the esophagogastric junction (AEG) is increasing, but the surgical strategy for AEG remains controversial. We hypothesized that sentinel node (SN) mapping for AEG could be validated to avoid unnecessary lymphadenectomy and permit minimally invasive surgery. We examined the feasibility of SN mapping for AEG.

Methods

We enrolled 15 patients with preoperatively diagnosed cT1 N0 M0 primary AEG (Siewert type I, N = 3; Siewert type II, N = 12) lesions measuring <4 cm in diameter. The dual tracer method employing radioactive colloid and blue dye was used to detect SNs. The distribution of SNs was compared with that of metastatic lymph nodes in 52 patients who were surgically treated without SN mapping.

Results

SNs were successfully identified in all the patients. Two patients with lymph node metastasis had positive SNs identified via an intraoperative pathological examination, and the diagnostic sensitivity and accuracy based on the SN status were both 100 %. For Siewert type II AEG, the SNs were not detected in the lower mediastinum by intraoperative gamma probing. Thus, all surgical procedures were performed via a transhiatal approach. No patient without SN metastasis experienced cancer recurrence during a 38-month median follow-up. The distribution of SNs was similar to that of lymph node metastasis in the patients who were surgically treated without SN mapping.

Conclusions

We achieved 100 % SN detection. Our results suggested that SN mapping is feasible for AEG and highly sensitive and accurate in diagnosing lymph node metastasis. SN mapping may clarify the necessity of mediastinal lymph node dissection and individualize minimally invasive surgery.     

Intraoperative radioisotope sentinel lymph node mapping in non-small cell lung cancer

BACKGROUND: Lymph node metastases are the most significant prognostic factor in localized non-small cell lung cancer (NSCLC). Nodal micrometastases may not be detected. Identification of the first nodal drainage site (sentinel node) may improve detection of metastatic nodes. We performed intraoperative Technetium 99m sentinel lymph node (SN) mapping in patients with resectable NSCLC. METHODS: Fifty-two patients (31 men, 21 women) with resectable suspected NSCLC were enrolled. At thoracotomy, the primary tumor was injected with 2 mCi Tc-99. After dissection, scintographic readings of both the primary tumor and lymph nodes were obtained with a handheld gamma counter. Resection with mediastinal node dissection was performed and findings were correlated with histologic examination. RESULTS: Seven of the 52 patients did not have NSCLC (5 benign lesions, and 2 metastatic tumors) and were excluded. Forty-five patients had NSCLC completely resected. Mean time from injection of the radionucleide to identification of sentinel nodes was 63 minutes (range 23 to 170). Thirty-seven patients (82%) had a SN identified; 12 (32%) had metastatic disease. 35 of the 37 SNs (94%) were classified as true positive with no metastases found in other intrathoracic lymph nodes without concurrent SN involvement. Two inaccurately identified SNs were encountered (5%). SNs were mediastinal (N2) in 8 patients (22%). CONCLUSIONS: Intraoperative SN mapping with Tc-99 is an accurate way to identify the first site of potential nodal metastases of NSCLC. This method may improve the precision of pathologic staging and limit the need for mediastinal node dissection in selected patients.     

Sentinel node mapping performed before preoperative chemotherapy may avoid axillary dissection in breast cancer patients with negative or micrometastatic sentinel nodes

BACKGROUND: Sentinel node (SN) biopsy after preoperative chemotherapy (PC) in breast cancer patients is associated with a lower identification rate (IR) and an increased false-negative rate (FNR) compared with SN biopsy in untreated patients. Our aims were to examine the feasibility of SN mapping before PC and the possibility to assess the lymph node status after chemotherapy through a follow-up lymphatic mapping. METHODS: SN biopsy was performed in 45 clinically node-negative breast cancer patients before PC. A follow-up lymphatic mapping was done after completion of chemotherapy and irrespective of the lymph node status was followed by axillary lymph node dissection (ALND). RESULTS: SN mapping before chemotherapy identified a mean of 2.3 SNs in all patients (IR 100%). Nineteen patients revealed a negative SN; 26 patients had a positive SN (micrometastasis found in 6/26 patients). After PC follow-up lymphatic mapping was successful in 29 of 45 patients (IR 64%). IR for follow-up mapping was 80% for patients with a negative or micrometastatic SN before chemotherapy compared with 45% for patients with macrometastatic SNs (P = .027, Fisher exact test). None of the patients with a negative or micrometastatic SN before chemotherapy revealed positive lymph nodes after PC (P = .031, McNemar test) and the FNR for follow-up lymphatic mapping in these patients was 0%. Contrary to that, 15 of 20 patients with a macrometastasis before PC had positive nodes after chemotherapy, and the FNR of follow-up mapping in these patients was 50%. CONCLUSIONS: Patients with a negative SN before PC may forego complete ALND after PC, whereas this may not be valid for patients with macrometastatic SNs. Follow-up lymphatic mapping in patients with positive nodal status before chemotherapy is associated with a low IR and a high FNR.     

Is sentinel lymph node mapping indicated for isolated local and in-transit recurrent melanoma?

OBJECTIVE: To determine the feasibility of sentinel lymph node mapping in local and in-transit recurrent melanoma. SUMMARY BACKGROUND DATA: The accuracy of intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL) for identification of occult lymph node metastases is well established in primary melanoma. We hypothesized that LM/SL could be useful to detect regional node metastases in patients with isolated local and in-transit recurrent melanoma (RM). METHODS: Review of our prospective melanoma database of 1600 LM/SL patients identified 30 patients who underwent LM/SL for RM. Patients with tumor-positive sentinel nodes (SNs) were considered for completion lymph node dissection. RESULTS: Of the 30 patients, 17 were men and 13 were women; their median age was 57 years (range, 29-86 years). Primary lesions were more often on the extremities (40%) than the head and neck (33%) or the trunk (8%). At least 1 SN was identified in each lymph node basin that drained an RM. Of the 14 (47%) patients with tumor-positive SNs, 11 (78%) underwent complete lymph node dissection; 4 had tumor-positive non-SNs. The median disease-free survival after LM/SL was 16 months (range, 1-108 months) when an SN was positive and 36 months (range, 6-132 months) when SNs were negative. At a median follow-up of 20 months (range, 2-48 months), there were no dissected basin recurrences after a tumor-negative SNs. CONCLUSIONS: LM/SL can accurately identify SNs draining an RM, and the high rate of SN metastases and associated poor disease-free survival for patients with tumor-positive SN suggests that LM/SL should be routinely considered in the management of patients with isolated RM.     

Application of sentinel node biopsy to gastric cancer surgery

BACKGROUND: Sentinel node (SN) biopsy has been tried in the management of a variety of cancers with the hope that it would eliminate many unnecessary lymph node dissections, resulting in less morbidity. This important technique, however, has not been tried in gastric cancer surgery. The feasibility of SN biopsy and its accuracy in predicting the lymph node status in patients with gastric cancer were examined in the current study. PATIENTS AND METHODS: SN biopsy was performed in patients with T1 (n = 44) or T2 (n = 30) gastric cancers (ie, immediately after laparotomy, indocyanine green was injected around the primary tumor, and the green-stained nodes [SNs: 2.6 +/- 1.7 nodes per patient] were removed). Then, gastrectomy with extended lymphadenectomy was performed. The unstained nodes (non-SNs: 39 +/- 18 nodes per patient) were obtained from the resected specimens. Both SNs and non-SNs were subjected to histologic examination with hematoxylin-eosin. RESULTS: SNs could be identified in 73 of 74 patients (success rate, 99%). Of these 73 patients, 10 had lymph node metastases in SNs or non-SNs, or both; 6 in both SNs and non-SNs; 3 in SNs alone; and 1 in non-SNs alone. The sensitivity of the SN status in the diagnosis of the lymph node status of the patient was 90% (9/10) and specificity was 100% (63/63). Sensitivity was 100% in the T1 group (n = 44) and 88% in the T2 group (n = 29). CONCLUSIONS: SN biopsy using indocyanine green can be performed with a high success rate, and the SN status can predict the lymph node status with a high degree of accuracy, especially in patients with T1 gastric cancer.     

Risk Factors for Non-Sentinel Lymph Node Metastases in Patients with Breast Cancer. The Outcome of a Multi-institutional Study

Background In this multi-institutional prospective study, we evaluated whether we could identify risk factors predictive for non-sentinel lymph node (non-SN) metastases in breast cancer patients with a positive sentinel lymph node (SN). Methods In this multi-institutional study, 541 eligible breast cancer patients were included prospectively. Results The occurrence of non-SN metastases was related to the size of the SN metastasis (P = .02), primary tumor size (P = .001), and lymphovascular invasion (P = .07). The adjusted odds ratio was 3.1 for SN micro-metastasis compared with SN isolated tumor cells, 4.0 for SN macro-metastasis versus SN isolated tumor cells, 3.1 for tumor size (>3.0 cm compared with ≤3.0 cm), and 2.0 for lymphovascular invasion (yes versus no). There were no positive non-SNs when the primary tumor size was ≤1.0 cm (n = 24) [95% confidence interval (95% CI) 0%–14.0%]. The proportion of positive non-SNs ranged in a prognostic logistic regression model from 9.7% (95% CI 4.0%–23.0%) for patients with SN isolated tumor cells, tumor size of 1.1–3.0 cm, and without vessel invasion, to 72.6% (95% CI 47.0%–89.0%) for patients with SN macro-metastasis, tumor size >3.0 cm, and with vessel invasion. Conclusion We identified three predictive factors for non-SN metastases in breast cancer patients with a positive SN: size of the SN metastasis; primary tumor size; and vessel invasion. We were not able to identify a specific group of patients with a positive SN in whom the risk for non-SN metastases was less than 5%.     

Sentinel node biopsy performed before preoperative chemotherapy for axillary lymph node staging in breast cancer

Sentinel node (SN) biopsy in breast cancer patients following preoperative chemotherapy is associated with a decreased identification rate and an increased false-negative rate when compared to SN biopsy performed in untreated patients. We performed SN biopsy in 21 breast cancer patients scheduled for preoperative chemotherapy using either vital blue dye alone (n = 11) or in combination with a radiocolloid (n = 10). Following a mean of four cycles of preoperative chemotherapy, surgery to the breast and complete axillary lymph node dissection was performed irrespective of the SN status. A mean of 1.9 SNs were identified in all 21 patients, 12 were SN negative and 9 were SN positive. Preoperative chemotherapy decreased mean tumor size from 40.2 to 17.7 mm and breast conservation was possible in 14 of 21 patients (67%). All SN-negative patients and three of nine SN-positive patients had negative lymph nodes in the axillary specimen, whereas six of nine patients with a positive SN revealed lymph node metastases following preoperative chemotherapy. SN biopsy performed before preoperative chemotherapy found a 100% identification rate with no false-negative results. Following preoperative chemotherapy, SN-negative patients may forego a complete axillary dissection.     

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.