Lymphatic mapping and focused analysis of sentinel lymph nodes upstage gastrointestinal neoplasms

BACKGROUND: Lymph node analysis is essential for staging gastrointestinal (GI) neoplasms. Intraoperative lymphatic mapping and sentinel lymphadenectomy were originally described for melanoma but have not yet been investigated for most GI neoplasms. HYPOTHESES: (1) Lymphatic mapping and sentinel lymphadenectomy is feasible in GI neoplasms, (2) the sentinel node (SN) status reflects the regional node status, and (3) focused analysis of the SN improves staging accuracy. DESIGN: Prospective patient series. PATIENTS AND METHODS: Lymphatic mapping was performed in 65 patients with GI neoplasms by injecting 0.5 to 1 mL of isosulfan blue dye around the periphery of the neoplasm. Blue-stained SNs were analyzed by hematoxylin-eosin staining, multiple sectioning, and cytokeratin immunohistochemistry. RESULTS: Lymphatic mapping identified at least 1 SN in 62 patients (95%). Of the 36 cases with nodal metastasis, 32 (89%) had at least 1 positive SN and 15 (42%) had nodal metastasis only in the SN. In 11 cases, tumor deposits were identified by multiple sectioning (n = 2) or immunohistochemistry (n = 9) only. In 5 cases (8%), lymphatic mapping identified aberrant lymphatic drainage that altered the extent of the lymphadenectomy. CONCLUSIONS: Lymphatic mapping and sentinel lymphadenectomy are feasible in GI neoplasms and identify aberrant lymphatic drainage. The SN status accurately reflects the regional node status. Focused analysis of the SN increases the detection of micrometastases and may improve selection of patients for adjuvant treatment.     

Sentinel node mapping during laparoscopic distal gastrectomy for gastric cancer

Background The goal of this study was to evaluate the feasibility and accuracy of sentinel node (SN) mapping with endoscopic submucosal blue dye injection during laparoscopic distal gastrectomy for gastric cancer. Methods Thirty-four patients affected by gastric adenocarcinoma without gross clinical serosal invasion and distant metastasis were prospectively enrolled. At the start of the surgery, 2 ml of 2% patent blue was endoscopically injected into the submucosal layer at four points around the site of the primary tumor. Sentinel nodes were defined as nodes that were stained by the blue dye within 5–10 min after the dye injection. After identification and removal of sentinel lymph nodes, each patient underwent laparoscopic distal gastrectomy with D1 (n = 2) or D2 (n = 32) lymphadenectomy. Results Of the 34 patients, 14 had positive nodules (41%). SNs were detectable as blue nodes in 27 (80%) of 34 patients. The mean number of dissected lymph nodes per patient was 31 ± 10 (range = 16–64) and the mean number of blue nodes was 1.5 (range = 1–4). Only five (sensitivity 36%) of 14 N(+) patients had at least one metastatic lymph node among the SNs identified. In these 14 patients the sentinel node was traced in 12 cases. Sentinel node status diagnosed the lymph node status with 74% accuracy. In early gastric cancer (n = 18), three patients had lymph node metastasis. These early gastric cancer patients with nodal metastases had at least one metastatic lymph node among the SNs identified (sensitivity 100%). Conclusions Blue dye SN mapping during laparoscopic distal gastrectomy seems to be a feasible and accurate diagnostic tool for detecting lymph node metastasis in patients with early-stage gastric cancer in which the accuracy of the method was 100%. However, in more advanced gastric cancer the results are not satisfactory. Validation of this method requires further studies on technical issues, including selection of the tracers.     

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.     

Laparoscopic lymphatic mapping and sentinel lymph node detection in colon cancer: technical aspects and preliminary results

Background The utility of lymph node mapping to improve staging in colon cancer is under evaluation. Laparoscopic colectomy for colon cancer has been validated in multicentric trials. This study assessed the feasibility of lymph node mapping in laparoscopic colectomy for colon cancer. Methods From March 2004 to December 2005, 22 patients were studied. Before resection, 2 to 3 ml of Patent Blue V dye was injected subserosally around the tumor. Colored lymph nodes were marked as sentinel nodes (SNs) with metal clips, and laparoscopic colectomy with lymphadenectomy was completed as normal. In SNs, multiple 4-μm slices at 50-μm intervals were stained with hematoxylin and eosin and examined. Anticytokeratin antibody immunostaining was applied in doubtful cases. Other lymph nodes were examined with multiple slices at 100- to 500-μm intervals by standard methods. Results The SN detection rate was 100%, although ex vivo lymph node mapping was necessary for an obese patient. Five patients (22.7%) were SN positive. There was one false-negative SN (16.7%). In two cases (9.1%) with aberrant lymphatic drainage, lymphadenectomy was extended. The SN reflected the status of the regional lymph nodes in 21 patients (95.4%). Accuracy was 95.4%, and negative predictive value was 94.1%. Conclusions Laparoscopic lymphatic mapping and SN removal is feasible in laparoscopic colectomy for colon cancer. Although the false-negative rate was high (16.7%), the overall results are promising and justify prospective studies to determine the real accuracy and false-negative rate for the technique. Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), April 26–29, 2006, Dallas, Texas, USA     

Lymphatic mapping and sentinel lymphadenectomy for breast cancer.

OBJECTIVE: The authors report the feasibility and accuracy of intraoperative lymphatic mapping with sentinel lymphadenectomy in patients with breast cancer. SUMMARY BACKGROUND DATA: Axillary lymph node dissection (ALND) for breast cancer generally is accepted for its staging and prognostic value, but the extent of dissection remains controversial. Blind lymph node sampling or level I dissection may miss some nodal metastases, but ALND may result in lymphedema. In melanoma, intraoperative lymph node mapping with sentinel lymphadenectomy is an effective and minimally invasive alternative to ALND for identifying nodes containing metastases. METHODS: One hundred seventy-four mapping procedures were performed using a vital dye injected at the primary breast cancer site. Axillary lymphatics were identified and followed to the first ("sentinel") node, which was selectively excised before ALND. RESULTS: Sentinel nodes were identified in 114 of 174 (65.5%) procedures and accurately predicted axillary nodal status in 109 of 114 (95.6%) cases. There was a definite learning curve, and all false-negative sentinel nodes occurred in the first part of the study; sentinel nodes identified in the last 87 procedures were 100% predictive. In 16 of 42 (38.0%) clinically negative/pathologically positive axillae, the sentinel node was the only tumor-involved lymph node identified. The anatomic location of the sentinel node was examined in the 54 most recent procedures; ten cases had only level II nodal metastases that could have been missed by sampling or low (level I) axillary dissection. CONCLUSIONS: This experience indicates that intraoperative lymphatic mapping can accurately identify the sentinel node--i.e., the axillary lymph node most likely to contain breast cancer metastases--in some patients. The technique could enhance staging accuracy and, with further refinements and experience, might alter the role of ALND.     

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.     

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%).     

Radio-guided sentinel node detection for gastric cancer

BACKGROUND: Radio-guided detection of sentinel nodes (SNs) has been used to predict regional metastases in patients with malignant melanoma and breast cancer. However, the validity of the SN hypothesis is still controversial for gastrointestinal cancers including gastric cancer. The aim of this study was to test the feasibility and accuracy of radio-guided mapping of SNs for gastric cancer. METHODS: Some 145 consecutive patients with gastric cancer diagnosed as T1 or T2 and evaluated clinically as N0 were enrolled. Endoscopic injection of technetium-99m-radiolabelled tin colloid was performed before operation and radioactive SNs were identified with a gamma probe. Standard radical gastrectomy with lymphadenectomy was performed in all patients and all resected nodes were evaluated by routine histopathological examination. RESULTS: Using radio-guided methods, SNs were detected in 138 (95.2 per cent) of 145 patients. The SN was positive in 22 of 24 patients with lymph node metastasis. The incidence of metastasis in the SNs (7.8 per cent) was significantly higher than that in the non-SNs (0.3 per cent) (P < 0.01). The diagnostic accuracy according to SN status was 98.6 per cent (136 of 138). CONCLUSION: Radio-guided SN mapping is an accurate diagnostic procedure for detecting lymph node metastasis in patients with early-stage gastric cancer.     

Sentinel lymph node procedure followed by laparoscopic pelvic and paraaortic lymphadenectomy in women with <Emphasis Type="Underline">IB2-II</Emphasis> cervical cancer

Objective To evaluate the contribution of the sentinel node (SN) procedure followed by pelvic and paraaortic lymphadenectomy to determine lymph node status in women with locally advanced cervical cancer. Patients and methods A total of 21 women with locally advanced cervical cancer underwent a first laparoscopic SN procedure and pelvic and paraaortic lymphadenectomy followed by concurrent chemoradiotherapy (CCR). Laparoscopic radical hysterectomy was performed after CCR when the pelvic and paraaortic nodes were not involved. Results SNs were detected by means of lymphoscintigraphy in 10 women (47.6%) and intra-operatively in 14 women (66.6%). Of the latter 14 patients, 9 (64%) had an involved SN and 1 of the remaining 5 had pelvic non-SN metastases. The SN false-negative rate was 10%. At final histology, 13 of the 21 women (62%) had lymph node metastases. The total number of recovered pelvic non-SNs was 262, and 10 nodes in 8 women were involved. The total number of paraaortic non-SNs was 255, and 2 nodes in 2 women were involved. Conclusion This study shows the poor correlation between pre-operative lymphoscintigraphy and surgical SN mapping in women with locally advanced cervical cancer. A high proportion of women had SN metastases, underlining the importance of multiple sectioning and immunohistochemical staining of SNs.     

Intraoperative lymphatic mapping and the sentinel node concept in colorectal carcinoma

BACKGROUND: Orderly progression of nodal metastases has been described for melanoma and breast cancer. The first draining lymph node, the sentinel node, is also the first to contain metastases and accurately predicts nodal status. The aim of this study was to assess the feasibility of lymphatic mapping and sentinel node biopsy in colorectal cancer. METHODS: In 50 patients with colorectal cancer patent blue dye was injected around the tumour. After resection of the tumour the specimen was examined to identify blue-stained lymph nodes. Routine histopathological examination was performed on all nodes and the blue, haematoxylin and eosin-stained tumour-negative nodes were tested immunohistochemically. RESULTS: Lymphatic mapping was possible in 35 of 50 patients (70 per cent). Pathological examination with haematoxylin and eosin staining showed lymph node metastases in 20 of 35 patients. In eight of these 20 patients the blue nodes showed tumour, while in 12 the blue nodes were not involved. This represents a false-negative rate of 60 per cent. CONCLUSION: Lymphatic mapping using patent blue dye is feasible in colorectal cancer. The blue-stained nodes do not predict nodal status of the remaining lymph nodes in the resected specimen. The concept of lymphatic mapping and sentinel node identification is not valid for colorectal 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 localization in primary melanoma: preoperative dynamic lymphoscintigraphy, intraoperative gamma probe, and vital dye guidance

BACKGROUND: Sentinel node (SN) biopsy can be used to select patients with primary melanoma for therapeutic lymphadenectomy. The aim of the study was to assess the efficacy of 3 methods to locate the SN: preoperative dynamic lymphoscintigraphy, intraoperative patent blue dye (PBD), and gamma-detecting probe (GDP). METHODS: We studied 133 patients with cutaneous melanoma and clinically negative lymph nodes. Within 24 hours before surgery, colloid labeled with technetium 99m was injected intradermally around the site of the primary melanoma. The patients were studied before their operations by using dynamic lymphoscintigraphy. A total of 208 SNs were found in 164 lymph node basins. In addition, all the patients had PBD injected immediately before the surgical procedure. When the blue-stained node was identified intraoperatively, its radioactivity level was measured with the GDP. In the absence of blue coloration, the GDP was used to trace the SN. RESULTS: Of 208 SNs, 168 (80.8%) were identified in the regional draining basin during intraoperative lymphatic mapping by using PBD. By using the GDP method, 202 (97.1%) of 208 were identified (GDP vs PBD; P < .01). By combining the 2 methods, 206 (99%) of 208 SNs were detected. Of the 133 patients, 29 (21.8%) had pathologically positive SNs, and were subsequently subjected to regional lymphadenectomy. In 26 (89.7%) of 29 patients, the SN was the only node with metastasis. Three cases (10.3%) of recurrence in patients with microscopic SN metastasis and 7 cases (6.7%) of recurrence in patients without SN metastasis were found during a median follow-up of 566 days. CONCLUSIONS: Preoperative dynamic lymphoscintigraphy and intraoperative mapping with PBD and GDP offer simple and reliable methods of staging regional lymph nodes without subjecting every patient to a regional lymphadenectomy.     

Radioisotope guided pelvic lymph node dissection for prostate cancer

PURPOSE: The localization of lymph node metastases in prostate cancer varies enormously. Due to high morbidity complete pelvic lymphadenectomy is often decreased to modified staging lymphadenectomy, resulting in loss of sensitivity for detecting micrometastases. Based on the promising results of intraoperative gamma probe application for identifying sentinel lymph nodes in malignant melanoma, breast and penis cancer, we identified sentinel lymph nodes in prostate cancer using a comparable technique. MATERIALS AND METHODS: In 117 patients 99mtechnetium nanocolloid was transrectally injected directly into the prostate under ultrasound guidance 1 day before pelvic lymphadenectomy. Thereafter dynamic lymphoscintigraphy was done. Initially lymph nodes identified as sentinel lymph nodes by the gamma probe were removed and subsequently modified pelvic lymphadenectomy was performed. RESULTS: Lymphatic metastasis was detected in 28 cases. An average of 4 sentinel lymph nodes were identified per patient in 25 of 27 patients with micrometastasis, of which those in 24 contained micrometastasis for 96% sensitivity. In contrast, sensitivity of modified pelvic lymphadenectomy was 81.5%. In 16 patients only sentinel lymph nodes were positive. An average of 21.8 lymph nodes (range 10 to 51) was dissected per patient at pelvic lymphadenectomy. Lymph node metastasis was noted in 6 of the 46 patients with a prostate specific antigen between 4 and 10 ng./ml. and in 8 of the 64 with a stage pT2 tumor. CONCLUSIONS: Our study shows individual variability of lymphatic drainage of the prostate and limited sensitivity for detecting positive lymph nodes when the pelvic dissection area is limited. Furthermore, our experience implies that the identification of sentinel lymph nodes is feasible, not only in breast cancer and malignant melanoma, but also in prostate cancer using a comparable technique.     

Lymphatic mapping and sentinel node biopsy in penis cancer. Feasibility study and preliminary report

Most patients with invasive squamous cell carcinoma of the penis do not have inguinal node metastasis at the time of diagnosis and 50% of those having palpable nodes are inflammatory. Penis cancer (PC) treatment implies resection of the primary tumor and inguinal lymphadenectomy; nevertheless, morbidity related to this procedure is high and its usefulness may be questioned in patients without metastasis in dissected nodes. Lymphatic mapping with sentinel node biopsy (LMSNB) is a valid alternative, useful in other neoplasias. The objective of this study is to determine if it is possible to identify a sentinel node (SN) in patients with PC. Patients with T1-2 PC without palpable nodes (N0) were included. LMSNB was carried out with the combined technique (blue dye and radiocolloid). All patients underwent an elective bilateral inguinal lymphadenectomy. Sensitivity and false negative index were calculated. SNs were sent for transoperative study with imprint technique and, definitively, with serial cuts and hematoxylin/eosin staining. Nine patients showed results with 32 lymph carrier zones and SN was identified in all of them, 4 regions had metastasis, in 3 the SN was metastatic and in one patient was metastasis-negative (false negative); sensitivity = 80%; false negatives index = 20%. Seven patients (77%) did not have node metastasis. LMSNB is an alternative for staging PC patients and could prevent unnecessary inguinal lymphadenectomies. A larger number of patients is required to validate the sturdy. The combined technique offers a high rate of success in SN identification.     

Sentinel lymph node biopsy for sparing axillary dissection in selected patients with breast cancer

Axillary lymph nodal status in breast cancer remains one of the more important prognostic factors. In early breast cancer axillary lymph node metastasis are found only in 10-18%. It can be deduced that in all these patients a complete axillary dissection is an overtreatment. The concept of sentinel lymph node (SN) was applied to breast cancer. Of course if SN examination gives negative findings, the patient will avoid axillary lymphadenectomy. 134 patients with localized breast cancer were evaluated for enrollment into the study. In 40 (29.8%) patients lymphoscintigraphy was performed together with an injection of vital dye to identify the SN, in 94 (70.1%) only vital dye was utilized. The mapping procedure was successful in 129 cases (96.2%). In our study there was concordance between SNs and axillary nodes in 120 out off 124 cases (96.7%). The false-negative rate was 4.8% (4/83). The overall sensitivity of the SN biopsy was 91.1% (41/45), with a negative predictive value of 95.1% (79/83). Five patients had SN negative and they decided do not undergo axillary lymphadenectomy. This study demonstrates that accurate SN identification was obtained combining lymphoscintigraphy and blue dye. Moreover, each method requires a suitable learning curve. After an accurate training, complete axillary lymphadenectomy can be avoided in selected patients.     

Parotid selective lymphadenectomy in malignant melanoma.

Malignant melanoma of the head and neck can metastasize to lymph nodes within the parotid gland. Selective lymphadenectomy is the modern method of staging regional lymph node basins in clinically localized melanoma. This procedure involves intraoperative lymphatic mapping and directed, selective removal of the first draining nodes or sentinel lymph nodes (SLNs). Historically, the assessment of parotid lymph nodes would involve a superficial parotidectomy with facial nerve dissection. Since 1993, 28 patients with localized melanoma of the head and neck have demonstrated lymphatic drainage to parotid lymph nodes on preoperative lymphoscintigraphy. The overall success rate of parotid selective lymphadenectomy is 86% (24 of 28 patients). Of the 28 patients, there were 6 early patients in whom blue dye alone was utilized intraoperatively, and the success rate is 50% (3 of 6 patients). When blue dye and radiocolloid mapping techniques are combined, the parotid selective lymphadenectomy is successful in 95% of patients (21 of 22 patients). Four of the 24 patients (17%) had metastases to the SLNs and underwent therapeutic superficial parotidectomy and/or modified radical neck dissection. After completion of the therapeutic superficial parotidectomy, 1 of the 4 patients was found to have an additional parotid (nonsentinel) node with melanoma metastases. None of the patients incurred injury to the facial nerve by parotid selective lymphadenectomy. To date, 2 of 28 patients (7%) have had regional recurrence to the parotid gland. Failure of the SLN technique may occur when blue dye alone is used, when human serum albumin (not sulfur colloid) is the radiocolloid, when prior wide excision and skin graft is present before lymphatic mapping, and when all SLNs are not retrieved. We conclude that parotid selective lymphadenectomy is a safe and reliable alternative to superficial parotidectomy for staging clinically localized melanoma of the head and neck.     

Lymphatic mapping and sentinel node biopsy during laparoscopic gastrectomy for early cancer

BACKGROUND/AIMS: Intraoperative lymphatic mapping and sentinel node (SN) biopsy can potentially be combined with minimally invasive surgery, but there are few reports of laparoscopic lymphatic mapping for gastrointestinal cancer. We examined the feasibility and accuracy of laparoscopic lymphatic mapping in predicting lymph node status in patients with gastric cancer. METHODS: Seventeen patients with gastric cancer invading the mucosal or submucosal layers (T1) underwent laparoscopic gastrectomy with lymphatic mapping between March 2001 and May 2002. The day before surgery, a technetium-99m-labelled tin colloid solution was injected endoscopically around the tumor. Immediately after the pneumoperitoneum, patent blue was injected. Gastrectomy was performed in all patients, and blue-stained or radioactive nodes were defined as SNs. Fresh SNs were immediately processed for frozen-section examination by hematoxylin-eosin (H and E) and immunohistochemical (IHC) staining. All non-SNs harvested from resected specimens were subjected to histological examination with H and E. RESULTS: SNs were detected in all patients by combination of the two kinds of tracers. Three patients had lymph node metastases in their final examination, and SNs in these 3 were operatively diagnosed as positive by H and E or IHC staining. Lymphatic mapping and SN biopsy under laparoscopic surgery were performed with 100% accuracy. CONCLUSION: Our preliminary study shows the feasibility of intraoperative lymphatic mapping in laparoscopic gastrectomy for T1 gastric cancer.     

Melanoma Metastases in Regional Lymph Nodes Are Accurately Detected by Proton Magnetic Resonance Spectroscopy of Fine-Needle Aspirate Biopsy Samples

Background Nonsurgical assessment of sentinel nodes (SNs) would offer advantages over surgical SN excision by reducing morbidity and costs. Proton magnetic resonance spectroscopy (MRS) of fine-needle aspirate biopsy (FNAB) specimens identifies melanoma lymph node metastases. This study was undertaken to determine the accuracy of the MRS method and thereby establish a basis for the future development of a nonsurgical technique for assessing SNs. Methods FNAB samples were obtained from 118 biopsy specimens from 77 patients during SN biopsy and regional lymphadenectomy. The specimens were histologically evaluated and correlated with MRS data. Histopathologic analysis established that 56 specimens contained metastatic melanoma and that 62 specimens were benign. A linear discriminant analysis–based classifier was developed for benign tissues and metastases. Results The presence of metastatic melanoma in lymph nodes was predicted with a sensitivity of 92.9%, a specificity of 90.3%, and an accuracy of 91.5% in a primary data set. In a second data set that used FNAB samples separate from the original tissue samples, melanoma metastases were predicted with a sensitivity of 87.5%, a specificity of 90.3%, and an accuracy of 89.1%, thus supporting the reproducibility of the method. Conclusions Proton MRS of FNAB samples may provide a robust and accurate diagnosis of metastatic disease in the regional lymph nodes of melanoma patients. These data indicate the potential for SN staging of melanoma without surgical biopsy and histopathological evaluation.     

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.