Distribution Of Sentinel Lymph Nodes Research Articles

Application value of indocyanine green fluorescence in sentinel lymph node biopsy for early-stage tongue cancer and oropharyngeal cancer.

Occult cervical lymph node metastasis is the most important reason for recurrence of early-stage tongue cancer and oropharyngeal cancer. Cervical sentinel lymph node (SLN) biopsy may help to identify them. Pigment dyes and radionuclide were used to label SLN. Both of them had shortage. This study aims to investigate the application and clinical value of indocyanine green fluorescence imaging in cervical SLN biopsy for patients with early-stage tongue cancer and oropharyngeal cancer. Retrospective analysis was conducted on 23 patients with early tongue cancer and oropharyngeal cancer, who received surgical treatment and used indocyanine green as a tracer to find SLN in Hunan Cancer Hospital from April to October 2021. The detection rate of SLN was calculated and the distribution of SLN in different regions of the neck was analyzed. SLN was successfully identified in 22 of 23 patients, with a detection rate of 95.65%. Among these 22 patients, 3 patients were found to have cancer metastasis, and the rate of occult lymph node metastasis was 13.63%. No pathologically positive lymph nodes were detected in SLN-negative patients, and thus the positive predictive rate was 100%. For patients with primary lesions located in the anterior 2/3 of the tongue, the constituent ratios of SLN in neck area I, II, III, and IV were 15.15%, 71.72%, 13.13%, and 0, respectively. For patients with primary lesions located in base of the tongue, the constituent ratios of SLN in neck area I, II, III, and IV were 0, 44.44%, 44.44%, and 11.12%, respectively. Indocyanine green fluorescence imaging has a high detection rate with accurate positive prediction in the anterior cervical SLN biopsy in patients with early-stage tongue cancer and oropharyngeal cancer. Meanwhile, it can also reflect the lymphatic drainage of tumors located at different primary sites, which has high clinical value.

Similar distribution of pelvic sentinel lymph nodes and nodal metastases in cervical and endometrial cancer. A prospective study based on lymphatic anatomy

ObjectiveComparing the anatomical distribution of metastatic and non-metastatic pelvic sentinel lymph nodes (SLN) in cervical and endometrial cancer. MethodsDetailed SLN mapping results were prospectively retrieved in cervical (n = 145) or high-risk endometrial cancer (n = 201) patients undergoing a robotic staging procedure. Cervically injected Indocyanine Green (ICG), allowing for reinjection in case of inadequate mapping, was used as tracer. An anatomically based definition of SLNs was adhered to evaluating the upper (UPP) and lower (LPP) paracervical lymphatic pathways. The positions of SLNs were intraoperatively depicted on an anatomical chart. A completory pelvic lymphadenectomy was performed. Mapping rates and anatomical distribution of SLNs and the location of pelvic nodal metastases were compared between groups. ResultsThe bilateral mapping rate was 97.9% and 95.0% for cervical and endometrial cancer respectively (p = .16). The proportion of typically positioned (interiliac and proximal obturator fossa) SLNs along the UPP was similar between groups (78.1% vs 82.1%, p = .09), and the rate of metastatic SLNs in the obturator fossa was 54.1% and 48.6% respectively (p = .45). All pelvic node positive women (cervical cancer n = 19, endometrial cancer n = 37) had at least one metastatic SLN. Anatomically typical positions could not be defined along the LPP. ConclusionThe anatomical location of SLNs and SLN metastases are similar in cervical and endometrial cancer suggesting that sensitivity results for an SLN concept in endometrial cancer and cervical cancer can be accumulated.

Anatomical distribution of sentinel lymph nodes in patients with endometrial cancer: a multicenter study

ObjectiveSentinel lymph node (SLN) mapping represents the standard approach in uterine confined endometrial cancer patients. The aim of this study was to evaluate the anatomical distribution of SLNs and the...

Sentinel node mapping using indocyanine green and near-infrared fluorescence imaging technology for endometrial cancer: A prospective study using a surgical algorithm in Indian patients.

Background:Indocyanine green (ICG) fluorescence with high-definition, three-dimensional imaging systems is emerging as the latest strategy to reduce trauma and improve surgical outcomes during oncosurgery.Materials and Methods:This is a prospective study involving 100 patients with carcinoma endometrium who underwent robotic-assisted Type 1 pan-hysterectomy, with ICG-directed sentinel lymph node (SLN) biopsy from November 2017 to December 2019. The aim was to assess the feasibility and diagnostic accuracy of SLN algorithm and to evaluate the location and distribution of SLN in pelvic, para-aortic and unusual areas and the role of frozen section.Results:The overall SLN detection rate was 98%. Bilateral detection was possible in 92% of the cases. Right side was detected in 98% of the cases and left side was visualised in 92% of the cases. Complete node dissection was done where SLN mapping failed. The most common location for SLN in our series was obturator on the right hemipelvis and internal iliac on the left hemipelvis. SLN in the para-aortic area was detected in 14% of cases. In six cases, SLN was found in atypical locations, that is pre-sacral area. Eight patients had SLN positivity for metastasis and underwent complete retroperitoneal lymphadenectomy. Comparison of final histopathological report with frozen section reports showed no false negatives.Conclusions:SLN mapping holds a great promise as a modern staging strategy for endometrial cancer. In our experience, cervical injection was an optimal method of mapping the pelvis. ICG showed a high overall detection rate, and bilateral mapping appears to be a feasible alternative to the more traditional methods of SLN mapping in patients with endometrial cancer. The ICG fluorescence imaging system is simple and safe and may become a standard in oncosurgery in view of its staging and anatomical imaging capabilities. This approach can reduce the morbidity, operative times and costs associated with complete lymphadenectomy while maintaining prognostic and predictive information.

Accuracy of Sentinel Lymph Node Biopsy in Breast Cancer: Pitfalls in the Application of Single Tracers.

BackgroundRadioisotopes and blue dyes are used as dual tracers in the current gold standard procedure of sentinel lymph node (SLN) biopsy (SLNB) performed for breast cancer. However, the blue dye or the radioisotope as a single tracer is also being applied in some institutes. We aimed to explore the risk factors for the miss-detection of SLNs with the radioisotope and the blue dye and to describe the distribution of SLNs missed by each tracer.Patients and MethodsPatients undergoing SLNB with radioisotope and blue dye as dual mapping agents were enrolled between August 2010 and August 2018. Radioactivity count, blue dye staining status, and size and location of each SLN were prospectively documented.ResultsIn total, 2382 SLNs from 1010 patients were included for statistical analyses. The sentinel node identification rate was 100% for dual tracers, 99.4% for radioisotope, and 89.1% for blue dye. SLN identification using the blue dye was more likely to fail in patients undergoing breast-conserving surgery (p < 0.001) and mastectomy with reconstruction (p = 0.005). Furthermore, miss-detection was significantly more frequent in smaller and uninvolved nodes. Among all SLNs, 8.2% were located in level II and one was in level III. Notably, single tracer of blue dye tended to fail in the detection of lymph nodes in higher levels (p < 0.001).ConclusionThis study explored the association between features and the incidence of the failure to detect SLNs using radioisotope and blue dye. The locations of the miss-detected SLNs are demonstrated to provide a reference for SLNBs conducted using blue dye or radioisotope as a single tracer.

1152P - Topographical distribution of sentinel lymph nodes in early tongue squamous cell carcinomas

BackgroundDespite advances in early detection, diagnosis, and treatment of oral squamous cell carcinoma (OSCC), the survival for patients with early stage remains at approximately 80% for the past 30 years. Regional lymph node metastasis is an important prognostic factor. Therefore, early detection of the cervical lymph nodes metastasis is expected to further improve survival. Sentinel lymph node biopsy (SLNB) is a widely accepted procedure in various human malignancies. In clinically N0 (cN0) early OSCC cases, SLNB has received considerable attention for its role in deciding whether to perform neck dissection. The objective in this study is to investigate the topographical distribution of sentinel lymph nodes (SLNs) and occult metastatic lymph nodes in early tongue squamous cell carcinoma (TSCC). MethodsA total of 64 patients with T1/2N0 TSCC underwent SLNB between 2001 and 2016. The location of SLNs was determined by radioisotope (RI) method with preoperative lymphoscintigraphy and intraoperative use of a handheld gamma probe, and evaluated by histopathological and genetic examinations. Patients with metastatic lymph nodes were treated with completion neck dissection. Excised lymph nodes were grouped into the neck level according to the international guidelines. ResultsSLNs were successfully identified with RI method (100%). The rate of SLN identified side was 84.5% in ipsilateral, 12.1% in bilateral, and 3.4% in contralateral. Nine of 64 patients (14.1%) had metastasis-positive SLN. Six patients with negative SLN developed the latent neck lymph node metastasis. There was no patients with metastatic involvement of neck level IV and V. The sensitivity, specificity, and accuracy was 60% (9/15), 100% (49/49), and 90.6% (58/64), respectively. ConclusionsSLNB is a minimally invasive and highly reliable method staging the cN0 for patients with early OSCC. Completion neck dissection of level I-III in SLNB-positive patients might be sufficient in patients with early TSCC. Our study showed that SLNB was helpful in clarifying unexpected bilateral or contralateral metastatic drainage patterns. SLNB provides more accurate staging than elective neck dissection or wait and see policy. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

SPECT-CT VISUALIZATION OF SENTINEL LYMPH NODES AND LYMPH FLOW FROM TONGUE CANCER

The main purpose of the study was to determine distribution of sentinel lymph nodes in patients with tongue cancer. SPECT-CT visualization of sentinel lymph nodes was performed in 19 primary patients with clinically T1-2N0M0 tongue cancer. SPECT-CT acquisition started 60-120 min after peritumoral injections of 99mTc-nannocolloids (100-150MBq in 0.3-0.4ml). Finally we analyzed lymph flow patterns and localization of lymph nodes with radiocolloids uptake. Bilateral lymph flow from the tongue cancer was detected in 9 (47%) of 19 patients. In 6 cases bilateral pattern was associated with tumors less than 5mm from medial sulcus of the tongue. On the contrary, in 9 of 10 patients with lesions more than 4mm from medial sulcus we detected monolateral lymph-flow. In 4 (21%) of 19 patients SPECT-CT visualized sentinel lymph nodes only in groups Ib-IIa. Modeling of radiotherapy with with standard and lymph-flow guided radiation fields was performed on Eclips treatment planning station. It demonstrated that with lymph-flow guided strategy irradiated volumes can be reduced from 1224 cm3 to 367 cm3, dose to spinal cord can be reduced from 24,7Gy to 14.3Gy, medial dose to contralateral parotid gland - from 24,6Gy to 12,4 Gy. SPECT-CT with radiocolloids can be successfully used for visualization of lymph flow from the primary tumour and subsequent radiotherapy planning.

Magnetic resonance sentinel lymph node imaging and magnetometer-guided intraoperative detection in prostate cancer using superparamagnetic iron oxide nanoparticles.

PurposeSentinel lymph node (LN) dissection (sLND) using a magnetometer and superpara-magnetic iron oxide nanoparticles (SPION) as a tracer was successfully applied in prostate cancer (PCa). The feasibility of sentinel LN (SLN) visualization on MRI after intraprostatic SPION injection has been reported. In the present study, results of preoperative MRI identification of SLNs and the outcome of subsequent intraoperative magnetometer-guided sLND following intraprostatic SPION injection were studied in intermediate- and high-risk PCa.Patients and methodsA total of 50 intermediate- and high-risk PCa patients (prostate-specific antigen >10 ng/mL and/or Gleason score ≥7) scheduled for radical prostatectomy with magnetometer-guided sLND and extended pelvic LND (eLND), were included. Patients underwent MRI before and one day after intraprostatic SPION injection using T1-, T2-, and T2*-weighted sequences. Diagnostic rate per patient was established. Distribution of SLNs per anatomic region was registered. Diagnostic accuracy of sLND was assessed by using eLND as a reference standard.ResultsSPION-MRI identified a total of 890 SLNs (median 17.5; IQR 12–22.5). SLNs could be successfully detected using MRI in all patients (diagnostic rate 100%). Anatomic SLN distribution: external iliac 19.2%, common iliac 16.6%, fossa obturatoria 15.8%, internal iliac 13.8%, presacral 12.1%, perirectal 12.0%, periprostatic 3.7%, perivesical 2.3%, and other regions 4.4%. LN metastases were intraoperatively found in 15 of 50 patients (30%). sLND had a 100% diagnostic rate, 85.7% sensitivity, 97.2% specificity, 92.3% positive predictive value, 94.9% negative predictive value, false negative rate 14.3%, and 2.8% additional diagnostic value (LN metastases only outside the eLND template).ConclusionMR scintigraphy after intraprostatic SPION injection provides a roadmap for intraoperative magnetometer-guided SLN detection and can be useful to characterize a reliable lymphadenectomy template. Draining LN from the prostate can be identified in an unexpectedly high number, especially outside the established eLND template. Further studies are required to analyze discordance between the number of pre- and intraoperatively identified SLNs.

Unexpected locations of sentinel lymph nodes in endometrial cancer

Objective: To evaluate the distribution of sentinel lymph node (SLN) areas following intraoperative cervical injection in endometrial cancer.

778 - Topographic distribution of sentinel lymph nodes in patients with renal tumours

778 - Topographic distribution of sentinel lymph nodes in patients with renal tumours

Topography of the sentinel node according to the affected lobe in lung cancer.

The objective of this study is to describe the anatomic location of the sentinel lymph node (SLN) of patients with lung carcinoma and to analyze its relationship with the characteristics of the tumor. 98 Stage I lung cancer patients were included in the study. SLN was marked just after performing the thoracotomy by injecting peritumorally 0.25mCi of nanocolloid of albumin (Nanocol1) labeled with Tc-99m in 0.3ml, and later, it was resected. For SLN micrometastasis analysis, CEACAM5, BPIFA1, and CK7 gene expression at mRNA level was studied. Possible relation between tumor characteristics and SLN location was analyzed. While most of the SLN were located in hilar area, we find a significantly higher number of SLN located in mediastinal stations when the lesion is in the left upper lobe (LUL). This difference disappears in the group of SLN with a positive result in the micrometastasis study. Regarding tumor size, squamous tumors and tumors located in the left lower lobe (LLL) were found significantly larger. The location of the SLN in patients with stage I lung cancer is predominantly hilar, being less consistent in the left hemithorax. The tumor size or histological type is not variables that affect this distribution. The distribution of SLNs with a positive result in the analysis of micrometastasis suggests further spread to the hilar areas when the lesion is in the LUL and to the mediastinal zones when it is in the LLL.

Recognition of sentinel lymph nodes in patients with papillary thyroid cancer by nano-carbon and methylene blue.

Objective:To compare the accuracy and feasibility of methylene blue and nano-carbon in clinical tracing of sentinel lymph nodes (SLNs) in patients with papillary thyroid cancer (PTC).Methods:Ninety-six PTC patients were selected and randomly divided into a methylene blue group and a nano-carbon group (n=48). During surgery, tracer agent was injected around the tumor, and SLNs were resected and subjected to frozen pathological examination. The results were compared with those of routine pathological examination after surgery.Results:Latent lymph node metastasis (level VI and lateral neck) was detected in both groups, with neck distribution of SLNs. There was no significant difference in the detection rate or accuracy of SLNs between two groups (P>0.05). The incorrect resection rate of parathyroid gland and incidence of temporary hypoparathyroidism in the methylene blue group were significantly higher than those of the nano-carbon group (t=4.137, P<0.05).Conclusions:The state of PTC lymph nodes can be well evaluated by SLN biopsy using both methylene blue and nano-carbon as tracers, but using nano-carbon has a lower incidence rate of parathyroid injury, with great clinical prospects accordingly.

PD42-01 MAGNETOMETER GUIDED SENTINEL LYMPHADENECTOMY AFTER INTRAPROSTATIC INJECTION OF SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES IN INTERMEDIATE- AND HIGH-RISK PROSTATE CANCER PATIENTS

INTRODUCTION AND OBJECTIVES: Sentinel lymph node (SLN) dissection (sPLND) in prostate cancer (PCa) is commonly performed after injection of radiolabeled tracers. This procedure requires nuclear medicine and exposes patients, as well as surgical staff, to radiation. We demonstrated the feasibility and safety of intraoperative SLN detection in PCa patients using a handheld magnetometer after intraprostatic injection of superparamagnetic iron oxide nanoparticles (SPIONs). This study determined whether this new technique can accurately determine LN stage in intermediateand high-risk PCa patients. METHODS: Enrolled 50 patients with intermediateand highrisk PCa (PSA >10 ng/ml and/or Gleason score 7; median PSA 10.78 ng/ml, IQR 7.41-19.18 ng/ml) in a prospective single center study (02/2015-09/2015). After transrectal intraprostatic SPIONs (Sienna+ ) injection a day earlier, patients underwent a magnetometer (SentiMag ) guided sPLND which was completed with an extended PLND as a reference, followed by radical retropubic prostatectomy. SLNs were detected both in vivo and ex vivo. Detection rate (number of patients with detected SLNs/total number operated) and sensitivity (number of patients with positive SLNs/total number of LN+ patients) were calculated. SLNs and LN metastases and their locations were recorded. RESULTS: At least one SLN was detected in all patients (detection rate 100%). A total of 460 SLNs (median 9, IQR 5.25-12.75) were identified, and in all 1143 LNs (median 22.5, IQR 19-26) were removed. Histopathology confirmed LN metastases in 18 patients (36%) having 43 positive LNs in total (median 2, IQR 1-3). Pathological analysis of ex vivo detected SLNs correctly categorized all LN+ patients (sensitivity 100%). However, intraoperative SLN detection missed one LN+ patient in which one positive SLN could not be detected resulting in a sensitivity of 94.4% (17/18). The anatomic distribution of SLNs was as follows: fossa obturatoria 32.17%, external iliac 31.09%, internal iliac 25.22%, periprostatic 5%, presacral 2.39%, perirectal 0.87%, perivesical 0.87, and other regions 2.39%. Of the LN metastases, 32.6% were localized in the external iliac, 25.6% in the fossa obturatoria, 23.3% in the internal iliac, 9.3% perivesical, 7.0% presacral, and 2.3% periprostatic. CONCLUSIONS: Our study indicate that this new magnetometer guided, radiation-free sentinel procedure which can be performed alone by an urologist has a high sensitivity for nodal staging in PCa patients at intermediateand high-risk for LN involvement. The reliability of intraoperative SLN detection by using this magnetometer system has to be verified in further studies.

The importance of para-aortic lymph nodes in sentinel lymph node mapping for endometrial cancer by using hysteroscopic radio-isotope tracer injection combined with subserosal dye injection: Prospective study

ObjectiveThe objective of this study is to evaluate the detection rate and diagnostic accuracy of sentinel lymph node (SN) mapping using hysteroscopic sub-endometrial injection of 99m-Technetium labeled phytate (Radio-isotope; RI method) and subserosal Indocyanine green (ICG) injection (Dye method) in patients with endometrial cancer. MethodsFrom April 2009 to December 2012, prospective evaluation of 57 Japanese endometrial cancer patients undergoing SN mapping using RI method combined with Dye method was done. To combine RI method or no was determined by a status of RI supply of the tracer injection day. As for 32 cases, both (RI+Dye) methods were used and 23 cases were performed only in Dye method. The primary endpoint was estimation of sensitivity and negative predictive value (NPV) of SN, and analysis of the distribution of SNs with metastasis. ResultsAt least one SN was detected in 100% and average number of detected SNs was 6.0 in RI+Dye method. Sensitivity and NPV were 100%, 100%, respectively. From results of SN mapping, 62.8% of SNs were present in pelvic and 37.1% in para-aortic lymph nodes (PAN). Total 56.3% of lymph nodes with metastasis were present in pelvic and 43.8% in PAN, and the distribution has no difference with SN mapping results (P=0.602). Among 13 cases with metastatic SNs, 76.9% cases showed metastasis in PAN. ConclusionsThis SN mapping procedure for endometrial cancer patients revealed high detection rate, sensitivity, NPV, and also indicated the importance of the SN exploration in PAN area.

Sentinel lymph node and skip metastases in gastric cancer: a prospective study.

The aim of the present study was to investigate localization and distribution of sentinel lymph node (SLN) in gastric cancer and influenced factors of skip metastasis. Eighty-nine cases with solitary or single station metastatic lymph nodes (LNs) among 779 gastric cancer patients were included in this study. D2 or D2+ lymph node dissection with total or distal gastrectomy had been performed. The location of SLNs and characteristics were analyzed retrospectively. Seventy-one patients (79.8%) had SLNs at the first level of the regional LN group and 18 cases (20.2%) had skip metastases SLNs. NO.7 (44.4%) and NO.8a (27.8%) were the most common sites of skip metastases. Multivariate analysis identified the differentiated degree of tumor as the only significant influenced factor of skip metastases (p=0.031). The number of metastatic SLNS was significantly greater in advanced gastric cancer patients (2.4 ± 1.4) than early gastric cancer patients (1.5 ± 0.9) (pT4 vs. pT1, p=0.002; pT4 vs. pT2, p=0.014; pT3 vs. pT1, p=0.018). The differentiated degree of gastric cancer is the most important influenced factor of skip metastases and NO.7 and NO.8a are the most important N2 LN stations that should be observed when lymphadenectomy is performed.

Lymphatic Mapping in Endometrial Cancer: Comparison of Hysteroscopic and Subserosal Injection and the Distribution of Sentinel Lymph Nodes

Endometrial cancer incidence increases over the age of 65 and lymphadenectomy in these women is a morbid procedure. Sentinel lymph node (SLN) should avoid extensive lymphadenectomy in node negative patients. The aim of this prospective study is to determine the feasibility and usefulness of lymphatic mapping and SLN identification in the management of endometrial cancer. From January 2004 to December 2007 101 women with endometrial cancer participated in the study. We injected Tc hysteroscopically, peritumorally 2 hours before laparotomy in 24 women. We applied Tc and blue dye subserously after laparotomy and before adhesiolysis in 67 women. Ten patients with metastatic disease in ovary, omentum, peritoneum, and bulky nodes were excluded from analysis. We detected SLN in 12 women (50%) in hysteroscopic group and in 49 women (73.1%) in subserous group. We identified 133 SLNs in 61 women. We found 20 SLNs (15.0%) in supraobturator region, 78 (58.6%) in external iliac area, 11 (8.3%) in paraaortal area, 13 (9.8%) on common iliac artery, 8 (6.0%) in medial part of lateral parametrium, and 3 (2.3%) in presacral area. Sentinel lymph node identification is a new strategy that can be used to examine nodal status with a high successful rate in breast, cervical, and vulvar cancer. Results in endometrial cancer are not as successful, however. In the future, it will be necessary to find optimal timing, the best route of application, and the "right" size of the Tc particles. Subserous application seems to be superior to hysteroscopic application.

Sentinel lymph node biopsy improves staging in early cervical cancer

The main study objective was to describe the distribution of sentinel lymph nodes (SLNs) and the prevalence of SLN micrometastases in patients with early cervical cancer. The secondary objective was to confirm the SLN detection rate and negative predictive value found in our preliminary study. We prospectively included 25 patients with early cervical cancer, each of whom received an injection of 120 MBq of technetium-99m for preoperative lymphoscintigraphy and intraoperative node detection using an endoscopic gamma probe. Patent blue dye was injected intraoperatively. SLNs were sought in the pelvic and para-aortic drainage areas. Radical iliac dissection was performed routinely at the end of the procedure. SLNs were examined after hematoxylin-eosin-saffron staining; negative specimens were assessed using immunohistochemistry. Most (85%) of the SLNs were in the inter-iliac territory. Para-aortic or parametrial SLNs were found respectively in 2 patients and common iliac SLNs in 5 patients. Thus 9/25 patients had additional information due to SLN detection. One metastasis and one micrometastasis were detected in SLNs. No patients had positive non-sentinel nodes with negative SLNs. SLN detection ensures the identification of SLNs in unusual locations in 36% of patients. SLN disease was found in 8% of our patients. Thus, SLN biopsy improves staging in patients with early cervical cancer. Studies in larger patient populations are needed to evaluate the clinical impact of SLN biopsy.

Further data on sentinel lymph node mapping in vulvar cancer by blue dye and radiocolloid Tc99

We studied the distribution of sentinel lymph nodes (SLNs) in vulvar cancer using blue dye and (99m)Tc radiocolloid and evaluated the techniques used, including the optimum timing of preoperative scintigraphy scans and its contribution to (99m)Tc SLN detection over that of the intraoperative handheld gamma probe. Fifty-nine women with squamous cell cancers <4 cm treated at our institution between December 2001 and December 2005 were included in this study. Blue dye alone was used in the first 16 women (group A) and the combination of (99m)Tc and blue dye was used on 43 women (group B). Of the 118 SLN detected in 82 groins, 83.9% (99) were sited in the superficial medial and intermediate inguinal chain, none were in superficial lateral groin, 16.1% (19) were deep femoral. The patient-specific SLN detection and false-negative rate in group B was 100% and 0%, compared to 68.8% (11/16 cases) and 6.3% (1/16) in group A. The optimum timing for preoperative lymphoscintigraphy scans was 45 min postinjection, but intraoperative use of the handheld gamma probe yielded 15% more "hot" nodes and allowed tailored placement of the lymphadenectomy incision. Eighty-four percent of SLNs were in the medial and intermediate region of the superficial inguinal chain, 16.1% were deep femoral. The combined use of (99m)Tc radiocolloid and blue dye was significantly superior at SLN detection than blue dye alone. (99m)Tc SLN detection using the intraoperative handheld probes was not enhanced by preoperative scintigraphy scans.

1053: Distribution of Sentinel Lymph Nodes in Patients With Cervical Cancer- Implications for Target Volumes in Radiation Therapy?

1053: Distribution of Sentinel Lymph Nodes in Patients With Cervical Cancer- Implications for Target Volumes in Radiation Therapy?

Topographic distribution of sentinel lymph nodes in patients with cervical cancer

Background Since the introduction of the sentinel concept in cervical cancer in 1999, various studies have been demonstrated the feasibility, detection rate and sensitivity and rate of false-negative sentinel lymph nodes (SLN). There are only limited data regarding the mapping of the removed SLN. A correlation between the localization of SLN and the tumor stage, histology or marker substance has never been investigated. Methods Between 2/2000 and 6/2005, the SLN distribution of 151 patients with histologically confirmed cervical cancer (FIGO stages IA n = 21, IB n = 95, IIA n = 14, IIB n = 18, IIIB n = 2, IVA n = 1), who participated in the ongoing “Uterus 3” sentinel study of the German Association of Gynecologic Oncologists (AGO), was retrospectively analyzed with respect to the histology, tumor stage and detection substance. The tumors comprised mostly of squamous cell carcinomas (75.5%) with a smaller fraction of adenocarcinomas (24.5%). Results Altogether, 406 SLN, an average of 2.7 (1–7) SLN per patient, were removed. More than one SLN was detected in 111 patients (73.5%). SLN were found unilaterally in 70 patients (46.4%) und bilaterally in 81 patients (53.6%). SLN sites were paraaortic in 4%, common iliac in 5%, external iliac in 5%, internal iliac in 8%, interiliac in 71% and parametric in 7%. Irrespective of the detection drug applied, most SLN were interiliac (blue 70%, TC 67%, TC and blue 71%). Combined application of technetium and blue dye revealed significantly more SLN in the paraaotic region ( P = 0.006). Adenocarcinomas and squamous carcinomas did not differ in the distribution of SLN ( P = 0.205). The majority of SLN are interiliac in all tumor stages (FIGO IA 76%, IB 68%, IIA 61%, IIB 83%, III and IV 88%). Conclusions Removal of SLN in the external iliac, interiliac and obturator area enables evaluation of more than 80% of all SLN. The pattern of SLN is independent from histology and tumor stage. Combined use of technetium and blue dye detects sentinels more frequently in the paraaortic region than a single marker.