Removal Of Sentinel Lymph Node Research Articles

Assessing the implications of sentinel lymph node removal in cervical cancer: an immunogenetic perspective – a SENTICOL ancillary study

BackgroundCervical cancer’s lymphatic spread primarily begins from the sentinel lymph nodes (SLNs), underlining their pivotal role in disease metastasis. However, these nodes’ immune gene expression profiles and immunoregulation mechanisms have...

Abstract PS05-03: MagSense® HER2, a Molecularly Targeted Magnetic Resonance Imaging Agent for the Detection of Axillary Nodal Metastasis in Subjects with Human Epidermal Growth Factor Receptor 2 Positive (HER2+) Breast Cancer

Abstract Background Precise nodal staging is critical in guiding systemic and regional treatments including surgery in the management of breast cancer. Regional nodal assessment includes axillary imaging (mostly by ultrasound) and lymph node sampling. Since imaging findings suggestive of nodal metastasis are based on size and morphologic changes and not specific to tumor type, pathologic confirmation through either biopsy or removal of sentinel lymph node (SLN) remains the gold standard. Imagion is developing the MagSense® HER2 Imaging Agent (MSH2IA), an anti-human epidermal growth factor receptor 2 (HER2) conjugated with iron oxide nanoparticles, for the detection of nodal metastasis in HER2+ breast cancer patients. MSH2IA is currently being investigated in a first-in-human phase 1 study (ACTRN12621000126819) in HER2+ breast cancer patients who are diagnosed to have suspicious nodes by conventional imaging. Methods The key objectives of the phase 1 study are safety and tolerability of MSH2IA and confirmation that MSH2IA drains to the axillary lymph nodes. The study also explores MSH2IA’s ability to detect metastatic nodes when used with magnetic resonance imaging (MRI), with tumor status assessed by standard tissue histopathology. All eligible subjects receive a 22.5 mg (iron equivalent) subareolar or peritumoral injection of MSH2IA. MRI of the axilla are obtained before and 24 to 72 hours after MSH2IA injection. Core biopsy or dissection of a node suspicious by ultrasound is obtained for histopathology assessments. After completing the first cohort of 6 subjects, the protocol was amended to include the insertion of an MRI compatible clip in a node suspicious by ultrasound to localize the suspicious node for core biopsy and postdose MRI scan. Review of MRI scans and histopathology are performed in respective central laboratories. Results Thirteen participants with HER2+ breast cancer have completed the study. MSH2IA appears safe and well tolerated. The imaging agent, as administered, is detectable by MRI and pathology, confirming that MSH2IA drains to the lymph nodes via the chosen route of administration. In postdose MRI scans, study central radiologists reported distinct and differentiable MRI appearance in morphologically normal and suspicious nodes. The presence of a distinct postdose MR image appearance was confirmed by a group of independent radiologists in a separate blinded review. While normal nodes appeared with homogeneous hypointensity, morphologically suspicious nodes showed partial irregular darkening and/or speckled heterogeneous hypointensity. In evaluable subjects, histopathology of the core biopsies obtained from the clipped nodes confirmed the presence of HER2+ nodal metastasis, providing preliminary evidence for node-level concordance between MRI vs pathology observations. Safety, imaging, and pathology results from all available subjects will be presented. This phase 1 study in Australia will be closing enrollment by July 31, 2023. A phase 2 study in the United States and elsewhere is being planned with the objectives of optimizing dose, schedule, and imaging parameters for best diagnostic performance for clinical utility. Conclusion Available data from the ongoing phase 1 study show that MSH2IA appears safe and drains to the axillary lymph nodes. MSH2IA displays a distinct and differentiable MRI appearance in nodes morphologically highly suspicious for tumor, which is confirmed to be HER2+ metastasis by histopathology by node level concordance. This data provides preliminary proof of principle for the mechanism of molecularly targeted MR imaging and suggests that MSH2IA has the potential to provide tumor-specific MR imaging not currently available in conventional axillary imaging. Citation Format: Jane Fox, Shanta Velaiutham, Natalie Yang, Eddie lau, Kowsi Murugappan, Beena Kumar, Alex Laslowski, Koushik Govindarajan, Steven Reich, Stephen Thomas, Nitika Neha, Marie Zhang, Isaac Bright. MagSense® HER2, a Molecularly Targeted Magnetic Resonance Imaging Agent for the Detection of Axillary Nodal Metastasis in Subjects with Human Epidermal Growth Factor Receptor 2 Positive (HER2+) Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS05-03.

VNOTES retroperitoneal sentinel lymph node dissection for endometrial cancer staging: First multicenter, prospective case series.

The current standard treatment for endometrial cancer is a laparoscopic hysterectomy with adnexectomies and bilateral sentinel node resection. A retroperitoneal vNOTES sentinel node resection has several theoretical potential advantages. These include being less invasive, leaving no visible scars, operating without Trendelenburg, and therefore offering the anesthetic advantage of easier ventilation in obese patients and following the natural lymph node trajectory from caudally to cranially and therefore a lower risk of missing the sentinel node. The aim of this study is to determine the feasibility of a retroperitoneal vNOTES approach to sentinel lymph node dissection for staging of endometrial cancer. A prospective multicenter case series was performed in four hospitals. A total of 64 women with early-stage endometrial carcinoma suitable for surgical staging with sentinel lymph node removal were operated via a transvaginal retroperitoneal vNOTES approach. The paravesical space was entered through a vaginal incision after injecting the cervix with indocyanine green. A vNOTES port was placed into this space and insufflation of the retroperitoneum was performed. Sentinel lymph nodes were identified bilaterally using near-infrared light followed by endoscopic removal of these nodes. A total of 64 women with early-stage endometrial cancer underwent sentinel lymph node removal by retroperitoneal vNOTES technique. All patients also underwent subsequent vNOTES hysterectomy and bilateral salpingo-oophorectomy. The median age was 69.5 years, median total operative time was 126 min and the median estimated blood loss was 80 mL. In 97% of the cases bilateral sentinel nodes could be identified. A total of 60 patients had negative sentinel nodes, three had isolated tumor cells and one had macroscopically positive sentinel nodes. No complications with sequel occurred. This prospective multicenter case series demonstrates the feasibility of the vNOTES approach for identifying and removing sentinel lymph nodes in women with endometrial carcinoma successfully and safely. vNOTES allows sole transvaginal access with exposure of the entire retroperitoneal space, following the natural lymph trajectory caudally to cranially, and without the need for a Trendelenburg position.

353 Targeted Axillary Dissection Does Benefit Patients with a Single Positive Node Prior to Neoadjuvant Chemotherapy

Abstract Aim Targeted Axillary Dissection (TAD) is a procedure where positive axillary nodes are clipped with a view to sentinel lymph node dissection plus removal of clipped nodes post-neoadjuvant therapies (NACT) rather than axillary lymph node clearance (ANC), reducing morbidity. This study aimed to assess whether patients with a single positive node undergoing NACT would benefit from TAD. Method Patients planned for TAD post-NACT were identified from the surgical diary from March 2020 – July 2022. Data were recorded for age, histopathology, MRI response and surgical procedure. Results Eighteen women were identified, mean age 46.7 (33- 63 years). 44% (8) had ER positive, HER2 negative invasive ductal carcinoma (IDC), 28% (5) had HER2 positive IDC, 22% (4) had triple negative IDC and 6% (1) had ER positive, HER2 negative lobular carcinoma. Treatment response on MRI was complete in 22% (4), near complete or very good in 11%(2), partial in 61% (11) with 6% (1) patient having stable disease. Four patients including the patient who had no response to chemotherapy opted for ANC post-NACT. Only 17% (1/6) patients with complete or good response had positive nodes post-NACT whereas 58% (7/12) of patients with partial or no response had positive nodes post-NACT. Conclusions Although the numbers in our study are small, TAD did benefit patients with a single positive node who have complete or good response to NACT. Larger multicentre studies are needed to confirm this and determine whether TAD is of benefit in patients who have partial or no response.

Comparing Methods for Targeted Axillary Dissection in Breast Cancer Patients: A Nationwide, Retrospective Study.

Several techniques exist for performing targeted axillary dissection (TAD) after neoadjuvant chemotherapy with the removal of the sentinel node and a marked metastatic lymph node (LN). Two-step methods include coil-marking of the metastatic LN at diagnosis and re-marking with an intraoperatively identifiable marker before surgery. Because nondetection of the marked lymph node (MLN) warrants axillary clearance and many patients achieve axillary pathological complete response (ax-pCR), the success of TAD is crucial. We compare various two-step TAD methods in a Danish national cohort. We included patients who received two-step TAD between January 1, 2016 and August 31, 2021. Patients were identified from the Danish Breast Cancer Group database and cross-checked with locally accessible lists. Data were extracted from the patient's medical files. We included 543 patients. In 79.4%, preoperative, ultrasound-guided re-marking was possible. Nonidentification of the coil-marked LN was more likely in patients with ax-pCR. The second markers used were hook-wire, iodine seeds, or ink marking on the axillary skin. Of patients with successful secondary marking, the MLN identification rate (IR) was 91%, and the sentinel node (SN) IR was 95%. Marking with iodine seeds was significantly more successful than ink marking with an odds ratio of 5.34 (95% confidence interval 1.62-17.60). The success rate of the complete TAD with the removal of MLN and SN was 82.3%. With two-step TAD, nonidentification of the coiled LN before surgery is frequent, especially in patients with ax-pCR. Despite successful remarking, the IR of the MLN at surgery is inferior to one-step TAD.

A study of recurrence, complication and survival rates in patients with early stage vulval cancer undergoing sentinel lymph node sampling: a single-centre experience.

Groin sentinel lymph node (SLN) identification and removal has become a standard of care for women with clinical early stage vulval cancer. There is evidence to support safe detection of the SLN with minimal morbidity. The purpose of this study is to report our experience of managing patients focusing on patient selection, adverse events, quality assurance of the procedure and any benefits and/or disadvantages to patients. This was a retrospective study of patients with clinical early stage vulval cancer in a cancer centre over 5years. Notes and hospital data were reviewed including admissions to emergency departments. Statistical software was used for the statistical analysis and the Kaplan Meier survival curve was generated to present survival rates. 61 cases were analysed. A total of 156 nodes have been removed and positive nodes were identified in 14 cases. In total, 9 women (14.75%) had disease recurrence within 5years from primary surgery. Overall, 4 patients (6.5%) developed groin recurrence. In 3 of these patients there was isolated groin recurrence (4.9%). The median length of admission was 3days and 6 cases were managed as day cases. Since the closure of the GROINNS-2 trial we have continued the procedure of SLN identification for women with clinical early stage vulval cancer. We have shown high level of adherence to our protocol and survival and complication rates comparable to other studies on the same field. There were a few patients managed as day-case which was of benefit to the patients.

Laparoscopic sentinel lymph node mapping with indocyanine green in endometrial cancer: surgeon’s learning curve (cumulative sum analysis)

ObjectivesTo evaluate surgeons’ learning curves for laparoscopic sentinel lymph node biopsy in endometrial cancer.MethodsA prospective observational study was performed at the Oncogynecology Center, Lithuanian University of Health Sciences Hospital, from...

Sentinel lymph node mapping in patients with endometrial hyperplasia: A practice to preserve or abandon?

ObjectivesTo compare outcomes of patients with premalignant endometrial pathology undergoing hysterectomy with or without sentinel lymph node (SLN) removal. Outcomes of interest included surgical adverse events (AEs), cancer status on final pathology, postoperative treatment, and The Cancer Genome Atlas (TCGA) molecular risk profiles. MethodsWe retrospectively identified patients with premalignant pathology on preoperative endometrial biopsy who underwent hysterectomy with or without SLN mapping/excision at our institution from 01/01/2017–12/31/2021. Clinical, pathologic, surgical, and TCGA profiling data were abstracted. Appropriate statistical tests were used. ResultsOf 221 patients identified, 161 (73%) underwent hysterectomy with SLN excision and 60 (27%) underwent hysterectomy without SLN excision. Median age and body mass index were similar between groups. Median operative time was 130 min for those who underwent SLN mapping/excision versus 136 min for those who did not (p = 0.6). Thirty-day postoperative AE rates were 9% (n = 15/161) and 13% (n = 8/60), respectively (p = 0.9). Ninety-eight (44%) of 221 patients had grade 1–2 endometrioid endometrial cancer on final pathology (4 [4%] were stage IB or higher). Ten (10%) of 98 patients, all within the SLN group, received adjuvant treatment. Among all patients, of 33 (15%) with TCGA molecular classification data, 27 (82%) had copy number-low, 3 (9%) microsatellite instability-high, 2 (6%) POLE-ultramutated, and 1 (3%) copy number-high disease. ConclusionsSLN assessment appears safe, detects a small number of occult nodal metastases for those upstaged, and provides additional staging information that can guide adjuvant treatment. SLN mapping should be discussed in preoperative counseling and offered using a shared decision-making approach.

VNOTES (vaginal natural orifice transluminal endoscopic surgery) staging of endometrial cancer with sentinel lymph nodes (551)

VNOTES (vaginal natural orifice transluminal endoscopic surgery) staging of endometrial cancer with sentinel lymph nodes (551)

Diagnostic accuracy of sentinel node biopsy in non-endometrioid, high-grade and/or deep myoinvasive endometrial cancer: A Turkish gynecologic oncology group study (TRSGO-SLN-006)

IntroductionThis study aimed to evaluate the diagnostic accuracy of the sentinel lymph node (SLN) mapping algorithm in high-risk endometrial cancer patients. MethodsTwo hundred forty-four patients with non-endometrioid histology, grade 3 endometrioid tumors and/or tumors with deep myometrial invasion were enrolled in this retrospective, multicentric study. After removal of SLNs, all patients underwent pelvic ± paraaortic lymphadenectomy. Operations were performed via laparotomy, laparoscopy or robotic surgery. Indocyanine green (ICG) and methylene blue (MB) were used as tracers. SLN detection rate, sensitivity, negative predictive value (NPV) and false-negative rate (FNR) were calculated. ResultsSurgeries were performed via laparotomy in 132 (54.1%) patients and 152 (62.3%) underwent both bilateral pelvic and paraaortic lymphadenectomy. At least 1 SLN was detected in 222 (91%) patients. Fifty-five (22.5%) patients had lymphatic metastasis and 45 patients had at least 1 metastatic SLN. Lymphatic metastases were detected by side-specific lymphadenectomy in 8 patients and 2 patients had isolated paraaortic metastasis. Overall sensitivity, NPV and FNR of SLN biopsy were 81.8%, 95% and 18.2%, respectively. By applying SLN algorithm steps, sensitivity and NPV improved to 96.4% and 98.9%, respectively. For grade 3 tumors, sensitivity, NPV and FNR of the SLN algorithm were 97.1%, 98.9% and 2.9%. ConclusionSLN algorithm had high diagnostic accuracy in high-risk endometrial cancer. All pelvic metastases were detected by the SLN algorithm and the isolated paraaortic metastasis rate was ignorable. But long-term survival studies are necessary before this approach becomes standard of care.

Evidence for disseminated tumor cells in lymphatic vessels afferent to sentinel lymph nodes in patients diagnosed with cervical cancer

BackgroundIn patients diagnosed with cervical cancer, the purpose of lymphadenectomy is the removal of lymph nodes for diagnosis and potential treatment of metastasized tumor cells. It is unclear if afferent lymphatic vessels harbor tumor cells and, thus, may pose additional risk for recurrence or progression if not removed.AimIn this feasibility study, we analyzed the lymphatic vessels afferent to sentinel lymph node (SLN) using a highly sensitive and specific molecular marker for cervical cancer cells.Methods and ResultsTwenty patients diagnosed with cervical cancer of FIGO stage IA1 to IIB2 underwent laparoscopic SLN removal. Labeling was done using patent blue and the afferent lymphatic vessels were harvested from the parametric tissue and frozen at −80°C. HPV DNA type was evaluated in the primary tumor. Lymphatic vessels afferent to the sentinel lymph nodes were analyzed for the presence of viral oncogene transcripts of the respective HPV type. In one of 18 patients, all with tumor stage ≤IBI and pN0 by conventional histopathology, HPV mRNA could be detected in two of four lymphatic vessels, whereas at least one of the lymphatic vessel biopsies of both patients with tumors ˃4 cm and pN1 status was HPV mRNA positive. No clinical correlation with recurrence after a median follow‐up of 9 years was noticed.ConclusionHPV mRNA indicative of disseminated tumor cells could be detected in lymphatic vessels. The relevance of harvesting lymphatic vessels afferent to SLN in order to increase oncologic safety will have to be investigated in a future prospective study.

Metastatic status of sentinel lymph nodes in breast cancer determined with photoacoustic microscopy via dual-targeting nanoparticles

Detection of sentinel lymph nodes (SLNs) is critical to guide the treatment of breast cancer. However, distinguishing metastatic SLNs from normal and inflamed lymph nodes (LNs) during surgical resection remains a challenge. Here, we report a CD44 and scavenger receptor class B1 dual-targeting hyaluronic acid nanoparticle (5K-HA-HPPS) loaded with the near-infra-red fluorescent dye DiR-BOA for SLN imaging in breast cancer. The small sized (~40 nm) self-assembled 5K-HA-HPPSs accumulated rapidly in the SLNs after intradermal injection. Compared with normal popliteal LNs (N-LN), there were ~3.2-fold and ~2.4-fold increases in fluorescence intensity in tumour metastatic SLNs (T-MLN) and inflamed LNs (Inf-LN), respectively, 6 h after nanoparticle inoculation. More importantly, photoacoustic microscopy (PAM) of 5K-HA-HPPS showed a significantly distinct distribution in T-MLN compared with N-LN and Inf-LN. Signals were mainly distributed at the centre of T-MLN but at the periphery of N-LN and Inf-LN. The ratio of PA intensity (R) at the centre of the LNs compared with that at the periphery was 5.93 ± 0.75 for T-MLNs of the 5K-HA-HPPS group, which was much higher than that for the Inf-LNs (R = 0.2 ± 0.07) and N-LNs (R = 0.45 ± 0.09). These results suggest that 5K-HA-HPPS injection combined with PAM provides a powerful tool for distinguishing metastatic SLNs from pLNs and inflamed LNs, thus guiding the removal of SLNs during breast cancer surgery.

Sentinel Lymph Node Removal After Neoadjuvant Chemotherapy in Clinically Node-Negative Patients: When to Stop?

The maximum number of sentinel lymph nodes (SLN) to be resected to accurately stage the axilla in patients undergoing neoadjuvant chemotherapy (NAC) for the treatment of clinically node-negative (cN0) breast cancer has not been determined. We sought to determine the sequence of removal of the positive SLNs in this patient population. All patients aged ≥ 18years diagnosed with cN0 invasive breast cancer who received NAC and underwent SLN surgery at Mayo Clinic Rochester between September 2008 and September 2018 were identified. Univariate analysis was performed to compare factors associated with positive nodes and where the first positive node was in the sequence of removal of the SLNs. We identified 446 cancers among 440 patients with a median age of 51 (IQR: 43, 61) years. At surgery, 381 (85.4%) cancers were pathologically node (ypN) negative and 65 (14.6%) were pN + . The number of nodes removed was similar for both patients with ypN0 and ypN + disease, with a median number of SLNs removed of 2.0 (IQR: 2.0, 3.0). Of all patients with a positive node, the first positive node was most commonly the 1st node removed (75.4%), and was identified by the 3rd SLN removed in all cases. Among cN0 patients treated with NAC, if a positive SLN is present, it is most commonly identified as the 1st sentinel node removed by the surgeon, and was identified by the 3rd sentinel node in our series. This suggests that once 3 SLNs have been resected, removal of additional sentinel lymph nodes does not add diagnostic value.

ASO Author Reflections: Sentinel Lymph Node Removal After Neoadjuvant Chemotherapy in Clinically Node-Negative Patients Can Stop After Removal of Three Lymph Nodes.

ASO Author Reflections: Sentinel Lymph Node Removal After Neoadjuvant Chemotherapy in Clinically Node-Negative Patients Can Stop After Removal of Three Lymph Nodes.

Neuroendocrine Cancer of the Breast: A Rare Entity.

Neuroendocrine breast cancer (NEBC) is a rare histotype of breast carcinoma that presents, in most cases, positive hormone receptors and negative HER2. Indeed, the analysis of gene expression profiles revealed that NEBC belongs mainly to the luminal subtype. Cases of HER2-positive and triple-negative NEBC are rare. The cardinal treatment of early NEBC is surgery, similar to the treatment of invasive non-special histological type carcinoma. The use of radiotherapy follows the criteria applied in infiltrating breast cancer of non-special histotype. In the post-operative phase, therefore after the surgical treatment of mammary quadrantectomy, or mastectomy associated with homolateral sentinel lymph node removal ± axillary dissection, based on the histopathological characteristics of the tumor, the use of chemotherapy (anthracycline + taxane) and/or hormone therapy, whether or not associated with anti-HER2 therapy (trastuzumab) is the rule. Literature data report the use of cisplatin and etoposide, as in small cell lung cancers. Most of the information currently available derive from single case reports or a series of clinical cases; it follows the difficulty of formulating definite recommendations on the correct management of this histological type of breast cancer. This review describes available knowledge on this rare entity to improve the diagnostic and therapeutic strategies and offer insights to stimulate exploration of the many aspects still unknown.

Pelvic sentinel lymph node biopsy in endometrial cancer—a simplified algorithm based on histology and lymphatic anatomy

ObjectiveTo achieve the full potential of sentinel lymph node (SLN) detection in endometrial cancer, both presumed low- and high-risk groups should be included. Perioperative resource use and complications should be...

Pelvic Sentinel lymph node detection in High-Risk Endometrial Cancer (SHREC-trial)—the final step towards a paradigm shift in surgical staging

Study aimsTo prospectively assess the diagnostic accuracy of a pelvic sentinel lymph node (SLN) algorithm in high-risk endometrial cancer (HREC). Patients and methodsConsecutive women with presumed FIGO stage I-II HREC underwent robotic surgery at two academic centres by five accredited surgeons. An anatomically based algorithm was adhered to, following cervical injection of indocyanine green (ICG), with reinjection of tracer in case of non-display of predefined lymphatic pathways. After removal of SLNs, a pelvic and infrarenal para-aortic lymphadenectomy was performed. Primary end-point was sensitivity of the SLN-ICG algorithm. Secondary end-points were sensitivity of the overall SLN algorithm (including macroscopically suspect nodes as SLNs), SLN mapping rates and morbidity of the SLN procedure. ResultsTwo hundred fifty-seven women were analysed; 54 had pelvic lymph node metastases (LNMs), and 52 of those were correctly identified by the SLN-ICG algorithm. In two women (one with false-negative ICG-SLNs and one non-mapped woman), the pelvic LNMs were identified by the overall SLN algorithm. The SLN-ICG algorithm had a sensitivity of 98% (95% confidence interval [CI] 89–100) and a negative predictive value of 99.5% (95% CI 97–100). The sensitivity of the overall SLN algorithm was 100% (95% CI 92–100) and the negative predictive value was 100% (95% CI 98–100). The bilateral mapping rate was 95%. Two women (1%) had isolated para-aortic metastases. No adverse events occurred during the SLN procedure. ConclusionWith a complete sensitivity to detect pelvic LNMs, the described pelvic SLN algorithm can, in the hands of experienced surgeons, exclude overall nodal involvement in 99% and thereby safely replace a full lymphadenectomy in HREC.

Removal of positive pelvic sentinel lymph nodes without additional lymphadenectomy does not compromise pelvic side wall control in patients with endometrial cancer

Objective: The aim of this study was to evaluate whether pelvic side wall (PSW) control is compromised by removal of positive sentinel lymph nodes (SLNs) alone compared with SLN and additional lymph node dissection (SLN + LND) in patients with stage IIIC1 endometrial cancer.

Oncological safety and perioperative morbidity in low-risk endometrial cancer with sentinel lymph-node dissection

Backgroundand Purpose: In endometrial cancer, staging is performed surgically. Controversy about the required extent of lymph node removal is ongoing. In low-risk endometrial cancer (FIGO Stage 1, endometrioid histology, Grades 1 and 2), the risk of lymph-node involvement is 4–17%. Since the introduction of near-infrared optics and the use of indocyanine green, the role of sentinel lymph node removal is increasing and could offer an appropriate balance between the morbidity of a complete lymph-node dissection and the risk of missing lymph-node involvement. MethodsIn this retrospective comparative study on low-risk endometrial cancer, the extent of surgical lymph-node assessment (no lymphadenectomy vs removal vs lymphadenectomy) in two European institutions was compared and analyzed on the basis of perioperative data and oncological outcome. ResultsThe study included 279 patients from: 103 (36.9%) had no lymphadenectomy, 118 (42.3%) underwent SLN removal and 58 (20.8%) underwent pelvic and/or para-aortic lymphadenectomy. There were significant differences among the groups in blood loss (p = 0.000), operation time (p = 0.000), and severity of postoperative complications (p = 0.063). In comparing only sentinel lymph-node removal vs no lymphadenectomy, there were no significant differences. No significant difference was seen between the extent of lymphadenectomy removal and the risk of recurrence. Age and Lymphovascular space invasion positivity were significant risk factors for recurrence (p = 0.004 and p = 0.019). ConclusionsIn early-stage, endometrial cancer, Grade 1 and 2, sentinel lymph node removal offers a convincing balance between oncological safety and perioperative morbidity. Especially in LVSI-positive cases, lymph-node evaluation in any form is crucial.

Abstract P3-03-06: Internal mammary chain sentinel nodes in early stage breast cancer patients: Towards selective removal

Abstract Background Internal mammary chain (IMC) sentinel nodes (SN) are visible in 1 out of 5 breast cancer patients on lymph scintigraphy after intra- or peritumoral injection of a radiopharmaceutical. The IMC SN status affects prognosis and treatment of breast cancer and IMC radiotherapy improves survival in selected patients. In contrast to the axillary SN, removal of the IMC SN is not routinely performed and often technically challenging. This study aims at determining the effect of IMC SN biopsy on recurrence-free survival (RFS) and overall survival (OS) and the identification of predictive factors for the development of IMC- and distant metastases. Methods All patients with IMC SNs were selected from a prospective database from 1999 to 2007. Following intratumoral injection of technetium-99m, conventional lymphoscintigraphy was performed. Sentinel nodes were removed in all regions with lymphatic drainage on scintigraphy. The RFS and OS were calculated for the total group and subgroups with tumor-positive, tumor-negative or non-removed IMC SN. Predictive factors were identified for tumor-positive IMC SN and for distant metastasis by regression analysis. Results Internal mammary chain SN biopsy was performed in 287 out of 336 patients (85%). The IMC SN was tumor-positive in 38 patients (13%). Patients with IMC metastasis had poorer OS compared to patients without IMC metastasis or a non-removed IMC SN (57%, 82% and 59% 10- year OS, respectively, p = 0.002). These patients also had worse RFS, mainly due to by the development of distant metastases (68%, 84% and 61% RFS, respectively, p = 0.002). Multivariable predictive for tumor-positive IMC SN were axillary metastases (PPV = 38.5%). Predictive factors for distant metastasis were tumor-positive IMC SN (HR 2.5, 95% CI; 1.0 - 5.8, p = 0.04), not removed IMC SN (HR 2.3, 95% CI; 1.0 - 5.1, P = 0.05), tumor diameter >1.5cm (HR 3.5, 95% CI; 1.6 - 8.4, p < 0.00) and age >65 years (HR 3.1, 95% CI; 1.2 - 7.7, p = 0.02, reference <50 years). Conclusion Breast cancer patients with tumor-positive IMC SN have worse 10- year survival than patients with tumor-negative IMC SN, mainly due to the development of distant metastasis. The clinically relevant predictive factor for distant metastasis is tumor size >1.5cm. Radiotherapy of the IMC can improve survival. However, the cardiotoxicity of parasternal radiotherapy must be weighed against the expected survival benefit. Therefore, our current protocol is to perform IMC SN biopsy in patients younger than 70 years with a tumor diameter >1.5cm. Citation Format: van Loevezijn AA, Bartels SA, van Duijnhoven FH, Heemsbergen WD, Bosma SC, Elkhuizen PH, Donswijk ML, Rutgers EJ, Oldenburg HS, Vrancken Peeters M-JT, van der Ploeg IM. Internal mammary chain sentinel nodes in early stage breast cancer patients: Towards selective removal [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-06.