Assessment Of Sentinel Lymph Nodes Research Articles

Laparoscopic sentinel lymph node assessment with indocyanine green: A standardized technique.

Laparoscopic sentinel lymph node assessment with indocyanine green: A standardized technique.

Intraoperative spectroscopic evaluation of sentinel lymph nodes in breast cancer surgery.

Sentinel lymph node (SLN) biopsy is a standard procedure for patients with breast cancer and normal axilla on imaging. Positive SLNs on histological examination can lead to a subsequent surgery for axillary lymph node clearance (ALNC). Here we report a non-destructive technique based on autofluorescence (AF) imaging and Raman spectroscopy for intra-operative assessment of SLNs excised in breast cancer surgery. A microscope integrating AF imaging and Raman spectroscopy modules was built to allow scanning of lymph node biopsy samples. During AF-Raman measurements, AF imaging determined optimal sampling locations for Raman spectroscopy measurements. After optimisation of the AF image analysis and training of classification models based on data from 85 samples, the AF-Raman technique was tested on an independent set of 81 lymph nodes comprising 58 fixed and 23 fresh specimens. The sensitivity and specificity of AF-Raman were calculated using post-operative histology as a standard of reference. The independent testset contained 66 negative lymph nodes and 15 positive lymph nodes according to the reference standard, collected from 78 patients. For this set of specimens, the area under the receiver operating characteristic (ROC) curve for the AF-Raman technique was 0.93 [0.83-0.98]. AF-Raman was then operated in a regime that maximised detection specificity, producing a 94% detection accuracy: 80% sensitivity and 97% specificity. The main confounders for SLN metastasis were areas rich in histiocytes clusters, for which only few Raman spectra had been included in the training dataset. This preliminary study indicates that with further development and extension of the training dataset by inclusion of additional Raman spectra of histiocytes clusters and capsule, the AF-Raman may become a promising technique for intra-operative assessment of SLNs. Intra-operative detection of positive biopsies could avoid second surgery for axillary clearance.

Multimodal ultrasound imaging: a method to improve the accuracy of sentinel lymph node diagnosis in breast cancer.

This study assessed the utility of multimodal ultrasound in enhancing the accuracy of breast cancer sentinel lymph node (SLN) assessment and compared it with single-modality ultrasound. Preoperative examinations, including two-dimensional ultrasound (2D US), intradermal contrast-enhanced ultrasound (CEUS), intravenous CEUS, shear-wave elastography (SWE), and surface localization, were conducted on 86 SLNs from breast cancer patients. The diagnostic performance of single and multimodal approaches for detecting metastatic SLNs was compared to postoperative pathological results. Among the 86 SLNs, 29 were pathologically diagnosed as metastatic, and 57 as non-metastatic. Single-modality ultrasounds had AUC values of 0.826 (intradermal CEUS), 0.705 (intravenous CEUS), 0.678 (2D US), and 0.677 (SWE), respectively. Intradermal CEUS significantly outperformed the other methods (p<0.05), while the remaining three methods had no statistically significant differences (p>0.05). Multimodal ultrasound, combining intradermal CEUS, intravenous CEUS, 2D US, and SWE, achieved an AUC of 0.893, with 86.21% sensitivity and 84.21% specificity. The DeLong test confirmed that multimodal ultrasound was significantly better than the four single-modal ultrasound methods (p<0.05). Decision curve analysis and clinical impact curves demonstrated the superior performance of multimodal ultrasound in identifying high-risk SLN patients. Multimodal ultrasound improves breast cancer SLN identification and diagnostic accuracy.

Sentinel lymph node assessment in patients with atypical endometrial hyperplasia: a systematic review and meta-analysis

ObjectiveThis systematic review and meta-analysis aimed to assess the rate of sentinel lymph node (SLN) metastases in patients with a pre-operative diagnosis of atypical hyperplasia/endometrial intra-epithelial neoplasia and endometrial cancer...

A prospective comparison of a modified miniaturised hand-held epifluorescence microscope and touch imprint cytology for evaluation of axillary sentinel lymph nodes intraoperatively in breast cancer patients.

The management of axillary lymph nodes in early-stage breast cancer patients has changed considerably, with the primary focus shifting from the examination of sentinel lymph nodes (SLNs) to toward the detection of all macro-metastases. However, current methods, such as touch imprint cytology (TIC) and frozen sections, are inadequate for clinical needs. To address this issue, we proposed a novel miniaturised epifluorescence widefield microscope (MEW-M) to assess SLN status intraoperatively for improved diagnostic efficiency. A prospective, side-by-side comparison of intraoperative SLN evaluation between MEW-M and TIC was performed. A total of 73 patients with 319 SLNs consecutive enrolled in this study. MEW-M showed significantly superior image quality compared to TIC (median score 3.1 vs 2.1, p < 0.0001) and had a shorter time to issue results (10.3 vs 19.4 min, p < 0.0001). Likelihood ratio analysis illustrated that the positive likelihood ratio value of MEW-M compared with TIC was infinitely great vs 52.37 (95% CI, 21.96-124.90) in model 1 (classifying results into negative/positive), infinitely great vs 52.37 (95% CI, 21.96-124.90) in model 2 (classifying results into macro-metastasis/others, and TIC results followed the same classification as model 1), respectively. Similarly, the negative likelihood ratio values of MEW-M compared with TIC were 0.055 (95% CI, 0.018-0.160) and 0.074 (95% CI, 0.029-0.190) in model 1; and 0.019 (95% CI, 0.003-0.130) vs 0.020 (95% CI, 0.003-0.140) in model 2, respectively. MEW-M is a promising technique that can be utilised to provide a rapid and accurate intraoperative assessment of SLN in a clinical setting to help improve decision-making in axillary surgery.

Intraoperative assessment of axillary sentinel lymph nodes by telepathology.

Although axillary dissection is no longer indicated for many breast cancer patients with 1-2 positive axillary sentinel lymph nodes (ASLN), intraoperative ASLN assessment is still performed in many institutions for patients undergoing mastectomy or neoadjuvant therapy. With recent advancements in digital pathology, pathologists increasingly evaluate ASLN via remote telepathology. We aimed to compare the performance characteristics of remote telepathology and conventional on-site intraoperative ASLN assessment. Data from ASLN evaluation for breast cancer patients performed at two sites between April 2021 and October 2022 was collated. Remote telepathology consultation was conducted via the Aperio eSlideManager system. A total of 385 patients were identified during the study period (83 telepathology, 302 on-site evaluations). Although not statistically significant (P = 0.20), the overall discrepancy rate between intraoperative and final diagnoses was slightly higher at 9.6% (8/83) for telepathology compared with 5.3% (16/302) for on-site assessment. Further comparison of performance characteristics of ASLN assessment between telepathology and conventional on-site evaluation revealed no statistically significant differences between deferral rates, discrepancy rates, interpretive or sampling errors, major or minor disagreements, false negative or false positive results as well as clinical impact and turn-around time (P ≥ 0.12). ASLN assessment via telepathology is not significantly different from conventional on-site evaluation, although it shows a slightly higher overall discrepancy rate between intraoperative and final diagnoses (9.6% vs. 5.3%). Further studies are warranted to ensure accuracy of ASLN assessment via telepathology.

Sentinel lymph node assessment in melanoma: current state and future directions.

Assessment of sentinel lymph node status is an important step in the evaluation of patients with melanoma for both prognosis and therapeutic management. Pathologists have an important role in this evaluation. The methodologies have varied over time, from the evaluation of dimensions of metastatic burden to determination of the location of the tumour deposits within the lymph node to precise cell counting. However, no single method of sentinel lymph node tumour burden measurement can currently be used as a sole independent predictor of prognosis. The management approach to sentinel lymph node-positive patients has also evolved over time, with a more conservative approach recently recognised for selected cases. This review gives an overview of past and current status in the field with a glimpse into future directions based on prior experiences and clinical trials.

Outcomes for patients with high-risk endometrial cancer undergoing sentinel lymph node assessment versus full lymphadenectomy

ObjectiveThe objective of this study was to determine the progression free survival (PFS) and overall survival (OS) among patients with high-risk endometrial cancer (EC) who underwent sentinel lymph node (SLN) mapping and dissection compared to patients who underwent pelvic +/− para-aortic lymphadenectomy (LND). MethodsPatients with newly diagnosed high-risk EC were identified. Inclusion criteria included patients who underwent primary surgical management from January 1, 2014 to September 1, 2020 at our institution. Patients were categorized into either the SLN or LND group based on their method of planned lymph node assessment. Patients in the SLN group had dye injected followed by successful bilateral lymph node mapping, retrieval, and processing per our institutional protocol. Clinicopathological and follow-up data were extracted from patient's medical records. The t-test or Mann-Whitney test was used to compare continuous variables and Chi-squared or Fisher's exact test were used for categorical variables. Progression-free survival (PFS) was calculated from the date of initial surgery to the date of progression, death, or last follow-up. Overall survival (OS) was calculated from the date of surgical staging to the date of death or last follow-up. Three-year PFS and OS were calculated using the Kaplan-Meier method, and the log-rank test was used to compare cohorts. Multivariable Cox regression models were used to assess the relationship between nodal assessment cohort and OS/PFS while adjusting for age, adjuvant therapy, and surgical approach. A result was considered statistically significant at the p < 0.05 level of significance and all statistical analysis was done using SAS version 9.4 (SAS Institute, Cary, NC). ResultsOut of 674 patients diagnosed with EC during the study period, 189 were diagnosed with high-risk EC based on our criteria. Forty-six (23.7%) patients underwent SLN assessment and 143 (73.7%) underwent LND. No difference was observed between the two groups in regards to age, histology, stage, body mass index, tumors myometrial invasion, lymphovascular space invasion, or peritoneal washing positivity. Patients in the SLN group underwent robotic-assisted procedures more frequently than those in the LND group (p < 0.0001). The three-year PFS rate was 71.1% (95% CI 51.3–84.0%) in the SLN group and 71.3% (95% CI 62.0–78.6%) in the LND group (p = 0.91). The unadjusted hazard ratio (HR) for recurrence in the SLN versus LND group was 1.11 (95% CI 0.56–2.18; p = 0.77), and after adjusting for age, adjuvant therapy, and surgical approach, the HR for recurrence was 1.04 (95% CI 0.47–2.30, p = 0.91). The three-year OS rate was 81.1% (95% CI 51.1–93.7%) in the SLN group and 95.1% (95% CI 89.4–97.8%) in the LND group (p = 0.009). Although the unadjusted HR for death was 3.74 in the SLN vs LND group (95% CI 1.39–10.09; p = 0.009), when adjusted for age, adjuvant therapy, and surgical approach, it was no longer significant with a HR of 2.90 (95% CI 0.94–8.95, p = 0.06). ConclusionsThere was no difference in three-year PFS in patients diagnosed with high-risk EC who underwent SLN evaluation compared to those who underwent full LND in our cohort. The SLN group did experience shorter unadjusted OS; however, when adjusting for age, adjuvant therapy and surgical approach, there was no difference OS in patients who underwent SLN compared to LND.

The role of micro-CT for intraoperative margin assessment of breast cancer.

e13620 Background: Breast-conserving surgery (BCS) followed by radiotherapy requires adequate removal of the malignancy with a negative margin. Accurate pathologic margin status is not available intraoperatively and is found to be positive in up to 20% of cases, necessitating re-excision. Specimen mammography (SM), used to find a biopsy marker, may assist with margin status but is only 55% sensitive for Intraoperative margin assessment (IMA). IMA methods are being increasingly investigated. Because micro-computed tomography (micro-CT) produces three-dimensional volumetric images, we aimed to evaluate the diagnostic sensitivity of micro-CT for IMA. Methods: We performed a systematic review according to the PRISMA guidelines by querying Scopus, MEDLINE, EMBASE, PubMed, and Google Scholar through 12/21/22. (https://osf.io/342h8). Studies evaluating the applications of micro-CT scanning in breast cancer were included for systematic review, and those reporting the diagnostic indices of micro-CT for IMA compared to histopathologic results were incorporated in a study-level meta-analysis. A random effects coefficient binary regression model was used when a high level of heterogeneity was observed. Results: Of the 2920 studies, 18 studies were selected. IMA was reported in 7 studies (388 specimens), tumor size in 3 studies, microcalcifications in 12 studies, and sentinel lymph node assessment in 1 study. Half of the studies were performed in the USA; the participant’s ages ranged from 33 to 82 years, and the tumor size was between 0.8 and 55.8mm. Image procurement time ranged from 4 to 30 minutes. A pooled diagnostic sensitivity of 0.67 (95% CI: 0.48 – 0.82) and specificity of 0.75 (95% CI: 0.63 – 0.84) was revealed, and the pooled accuracy was calculated based on the normal-error estimation as 0.76 (95% CI: 0.69 – 0.83) for IMA by micro-CT compared to the histopathological evaluation. Conclusions: Micro-CT can create 3D images of the internal structure and vasculature in less than 30 minutes and detects up to 67% of positive margins intraoperatively, preventing a future reoperation. Although the results of this review are promising, due to the high level of heterogeneity, further investigations should be pursued as to how and who should report the images and whether micro-CT may have a role in IMA. [Table: see text]

167P Deep learning-based whole slide image analysis to predict sentinel node status in the INSEMA cohort

As further de-escalation of axillary surgery is ongoing, new biomarkers that convey the same prognostic information as sentinel node status are called for. To predict sentinel node status, we trained a deep learning (DL) image analysis model on H&E-stained whole slide images (WSIs) of primary tumors. For training, we used cases from the INSEMA standard arm (n=762, ca. 94 % HR+/HER2-, 3.5 % G3, less than 1% pT3/4, 13 % SLN-positive) and a cohort from the Women’s Clinic in Mannheim, Germany (n=150, all HR+/HER2-, G2, pT1/2, ca. 16 % SLN positive). We also fitted a logistic regression with clinical data (pT stage, Ki-67) for this task. Models were tested on a holdout INSEMA set (n=381), and the image model also on the higher risk TCGA BRCA cohort (n=650, ca. 72% HR+, ca. 55% SLN+). Vice versa, we trained a model on TCGA WSIs and tested it on the other cohorts. During training, the image and the clinical model yielded Areas under the Receiver Operating Characteristic Curve (AUROCs) of 0.62 and of 0.77 on the Mannheim WSIs, respectively. However, performance of the image model was random on the INSEMA (determined by blinded assessment) and TCGA BRCA test sets. The clinical classifier retained an AUROC of 0.62 on the INSEMA set. Inclusion of the image classifier output in the logistic regression did not improve performance on INSEMA. The image model trained on TCGA also yielded random performance on the INSEMA and Mannheim cohorts. Image analysis algorithms trained on H&E stains of the primary tumors from INSEMA or TCGA using established techniques were unable to predict sentinel status, which may suggest a lack of systematic histological differences by lymph node status in these cohorts. Thus, DL-based WSI analysis may not be a good strategy to replace sentinel node assessment, especially in low- to intermediate-risk, hormone receptor-positive breast cancer.

Impact of sentinel lymph node assessment on the outcomes of patients with advanced endometrial cancer: A meta-analysis.

Sentinel lymph node (SLN) assessment is used to treat early endometrial cancer; however, its application in advanced endometrial cancer remains controversial. Therefore, we assessed the effects of SLN assessment and lymphadenectomy (LND) on the prognosis (survival rate and primary outcome) of patients with advanced endometrial cancer. Pertinent studies were selected from PubMed, Embase, Web of Science, and the Cochrane Library until March 19, 2022. Relevant studies were strictly screened according to the inclusion and exclusion criteria. Data from the included studies were extracted and their quality was evaluated. Then RevMan5.4 software was used for the meta-analysis. Four retrospective studies were included, which enrolled 7181 patients; 492 were treated with SLN and 6689 with LND. In terms of overall survival, there was no significant difference between the 2 groups (odds ratio = 1.14, 95% confidence interval: 0.92-1.41, I2 = 0%, P = .39). SLN assessment is an alternative to LND as a treatment modality for advanced endometrial cancer.

Impact of neoadjuvant chemotherapy in the surgical treatment of breast cancer

Introduction: Neoadjuvant chemotherapy is an increasingly frequent option in the treatment of breast cancer. One of the goals of neoadjuvant chemotherapy is to change the indication for a mastectomy to a conservative surgery, and for axillary lymphadenectomy to sentinel lymph node assessment. Methods: This was an observational, cross-sectional, retrospective study that evaluated response to neoadjuvant chemotherapy in breast cancer patients undergoing surgical treatment. Patients were divided into three groups when the surgery indication was changed after neoadjuvant chemotherapy: downgrade, unchanged, upgrade. Results: During the study period, 355 patients were included with a mean age of 55 years. Neoadjuvant chemotherapy promoted a downgrade in 38.7% of patients with indication for mastectomy and an upgrade in 36.8% of patients with indication for conservative surgery; in the total group, the maintenance of indication for surgery was 62,2%. In the axillary approach, lymphadenectomy downgrade was 6.9% and sentinel lymph node biopsy upgrade was 34% with 27% being due to positivity and 7% due to disease progression. Multivariate analysis found a significant difference between clinical staging and change in surgical indication for both breast and axilla (p&lt;0.0001). In the multivariate analysis of pathologic complete response and change of indication for breast and axilla surgery, triple negative and HER-2-positive tumors showed a significant difference (p&lt;0.0001). Conclusions: Neoadjuvant chemotherapy was able to perform a downgrade of breast and axilla surgery in few patients and there was no relationship between the change of indication and pathologic complete response

Is sentinel lymph node assessment useful in patients with a preoperative diagnosis of endometrial intraepithelial neoplasia?

ObjectiveTo determine the prevalence of underlying high-intermediate (high-IM) and high-risk endometrial cancer (EC) in patients with preoperative diagnosis of Endometrial intraepithelial neoplasia (EIN) and to assess the impact of the information retrieved from the sentinel lymph node (SLN) on adjuvant therapy. MethodsRetrospective cohort study of women undergoing hysterectomy, optional bilateral salpingo-oophorectomy (BSO) and lymph nodes assessment for EIN between December 2007 and August 2021. ResultsOne hundred and sixty two (162) eligible patients were included, of whom 101 (62.3%) had a final diagnosis of EIN, while 61 (37.7%) were ultimately diagnosed with carcinoma. Out of 15 patients with high-IM to high-risk disease (9.25% of all EIN), 12 had grade 2–3 EC including 8 with >50% myometrial invasion, 2 with serous subtype, 1 with cervical invasion and 2 with pelvic lymph nodes involvement. Of the 3 patients with grade 1 EC, one patient had disease involving the adnexa and 2 patients had tumor invading >50% of the myometrium and with lymphovascular space invasion (LVSI). Ten patients received vaginal brachytherapy after surgery, 3 patients with extrauterine spread were treated with systemic chemotherapy followed by vaginal brachytherapy and pelvic external-beam radiotherapy and 2 patients with early-stage serous carcinoma received chemotherapy followed by vaginal brachytherapy. ConclusionsInformation from SLN, even when negative, can be helpful in the management of patients with EC after preoperative EIN, as some patients are found to have high-IM to high-risk disease on final pathology. These patients would require either re-staging surgery or adjuvant external beam radiotherapy, both could be avoided by proper staging.

246 (PB-070) Poster - One-step nucleic acid amplification assay in palpable and non-palpable breast tumours

Background: The one-step nucleic acid amplification (OSNA) assay quantifies the cytokeratin 19 (CK19) messenger RNA copy number, which is currently being used for assessment of axillary sentinel lymph node (SLN) status in breast cancer. The total tumour load (TTL), defined as the total amount of CK19 mRNA copies in all positive SLNs, may help predicting additional metastatic axillary involvement besides SLN. There is evidence suggesting that palpable and non-palpable breast tumours manifest distinct pathological features, making tumour palpability a putative predictive factor of axillary lymph node involvement.

Lymph Node and Distant Metastases in Phyllodes Tumor of the Breast.

A 54-year-old woman who incidentally noticed a "knot" in her left breast subsequently underwent excisional biopsy which yielded a diagnosis of malignant neoplasm with sarcomatous features. Given the broad differential diagnosis and imaging findings, the patient underwent bilateral mastectomy and intraoperative sentinel lymph node assessment. An 8.5 cm tumor that was further classified as a malignant phyllodes tumor was identified in the left breast, while the frozen section interpretation came back as positive for metastatic disease which resulted in left axillary lymphadenectomy. Two months later the patient progressed to distant metastatic disease and unfortunately passed away within 6 months after her initial diagnosis. Lymph node metastasis in phyllodes tumor is an exceptionally rare event for which patients usually do not undergo intraoperative sentinel lymph node examination; however high clinical suspicion of metastatic disease would be evidence for further investigation.

A clinical diagnostic test on the detection of sentinel lymph node metastasis in breast neoplasms using a 1-step RT-PCR.

Currently, assessment of sentinel lymph node (SLN) requires cytology, hematoxylin-eosin (HE), and immunohistochemistry (IHC). However, routine pathological slides still suffer from certain sampling errors and have time limitations. This study sought to investigate the sensitivity and specificity of SLN detection by reverse transcription-polymerase chain reaction (RT-PCR), which quantifies the expression of mammaglobin and cytokeratin-19 genes to determine SLN status. The RT-PCR detection of cycles threshold (CT) values has a direct relationship with the lymph node metastasis. This study prospectively collected 256 sentinel lymph nodes from 150 patients diagnosed with breast cancer between August and November 2017. In the detection of metastases in lymph nodes, molecular markers can be verified at the cell-level and tissue-level of tumor cells. In this study, IHC results were used as the gold standard for judging sentinel lymph node status. (I) According to the established cell models, as the lymph nodes in tumor cells increase, RT-PCR CT values decrease. (II) 83 lymph nodes were first collected, and the interpretation criteria for the molecular detection results were determined based on the IHC results. (III) The statistical analysis showed that the sensitivity of the RT-PCR was 80.49% and the specificity was 91.55%. The positive predictive and negative predictive values were 64.71% and 96.06%, respectively. There was no significant difference between RT-PCR detection and IHC detection (P=0.076). Statistical chi-square analysis also showed that the difference between intraoperative freezing and immunohistochemistry was statistically significant (P=0.000). There was a statistically significant difference between intraoperative freezing and RT-PCR detection (P=0.000). RT-PCR detection is more sensitive than intraoperative frozen detection, and is closer to the results of immunohistochemistry. RT-PCR had objective and rapid output advantages, and was proven to be true and reliable. RT-PCR detection can not only rapidly assess sentinel lymph node status in breast cancer patients during surgery, but its accuracy is also close to that of IHC. Correctly determine whether to perform axillary lymph node dissection and improve the survival rate of patients.

526MO Pathological assessment of sentinel lymph node in early-stage cervical cancer: Results from the prospective SENTIX trial (CEEGOG-CX01; ENGOT-CX2)

Lymph node (LN) involvement is the key factor indicating adjuvant treatment in early-stage cervical cancer patients. Both macrometastases (MAC; >2mm) and micrometastases (MIC; 0.2-2 mm) are considered LN positive (pN1) since a negative impact of MIC similar to MAC has been confirmed by several studies. Although the majority of MIC are detected only by pathological ultrastaging of LN, no international protocol for pathological assessment has been agreed upon and still sparks controversy.

Prognostic Significance of Size, Location, and Number of Lymph Node Metastases in Endometrial Carcinoma.

Regional lymph node metastasis is a well-established negative predictive prognostic factor in endometrial carcinomas. Recently, our approach to the pathologic evaluation of lymph nodes in endometrial carcinomas has changed, mainly due to the utilization of immunohistochemical stains in the assessment of sentinel lymph nodes, which may result in the identification of previously unrecognized disease [particularly isolated tumor cells (ITCs)] on hematoxylin and eosin stained slides. However, the clinical significance of this finding is not entirely clear. Following the experience in other organs systems such as breast, the Eight Edition of the American Joint Committee on Cancer's Cancer Staging Manual has recommended utilizing the N0(i+) terminology for this finding, without impact in the final tumor stage. We performed a comparative retrospective multi-institutional survival analysis of 247 patients with endometrial carcinoma with regional lymph node metastasis of various sizes identified in nonsentinel lymphadenectomy, demonstrating that the cumulative survival of patients with isolated tumor cells in regional lymph nodes is not statistically different from patient with negative lymph nodes, and is statistically different from those with lymph nodes showing micrometastasis or larger metastatic deposits. In addition, we evaluated the prognostic implications of the number of involved regional lymph nodes, demonstrating a worsening prognosis as the number of involved lymph nodes increases from none to one, and from one to more than one. Our data suggests that regional lymph nodes with isolated tumor cells in patients with endometrial carcinoma should likely be considered, for staging purposes, as negative lymph nodes, simply indicating their presence with the (i+) terminology.

Does race impact uterine cancer surgical treatment: An SGO Clinical Outcomes Registry analysis (056)

<b>Objectives:</b> The age-adjusted mortality due to endometrial cancer (EC) among Black women (BW) is approximately 84% higher than it is for White women (WW). Multiple analyses of national registry data have revealed that BW with EC are more likely to receive guideline-discordant care. The objective of this study was to determine whether BW with EC in the SGO Clinical Outcomes Registry (SGO-COR) received surgical treatment differing from that of WW. <b>Methods:</b> The SGO-COR was comprised of validated clinical data from 29 SGO-COR centers collected between 2014 and 2018. Statistical analysis was performed using student's t-test and Chi-square with Stata v.14. A p-value of <0.05 was used for statistical significance. <b>Results:</b> In this cohort of 6984 total EC patients, 4338 underwent surgical management. Of those, 287 (6.6%) were Black, and 3792 (87%) were White. There was no difference in mean BMI (36.9 vs 36; p=0.86) or prevalence of diabetes (31% vs 26%; p=0.07) between BW and WW, but BW were more likely to be ASA >class II than WW (219/274, 80% vs 1921/3593, 53.4%; p<0.00001). Additional clinical data can be found in Table 1. BW were more likely to have > stage I disease (182/287, 63% vs 2980/3792, 78.5%; p<0.0001), non-endometrioid histology (135/287, 47% vs 702/3792, 18.5%; p<0.00001) and grade 3 disease (110/287, 38.3% vs 785/3792, 20.7%, p<0.00001). WW with stage I disease were more likely to undergo minimally invasive surgery (MIS) than BW with stage I disease (2693/2930, 91.9% vs 144/172, 83.7%, p=0.00019) as well as sentinel lymph node assessment (1004/2980, 33.6% vs 29/182, 16% p<0.00001). There was no difference in conversion to laparotomy between the groups (14/254, 5.5% for BW vs 116/3594, 3.2% for WW; p=0.05). There was no statistical difference in pelvic or para-aortic lymphadenectomy regardless of stage in BW versus WW. There were no differences in gross residual disease among BW and WW (9/223, 4% vs 2.1%, p=0.07). There was no difference in the rate of postoperative complications between BW versus WW. <b>Conclusions:</b> These SGO-COR results reflect several known trends, including BW being more likely to present with more advanced, higher-grade EC and non-endometrioid histology than WW. Contrary to previous studies, BW and WW received the same surgical care in some domains (rate of lymphadenectomy, presence of residual disease, rate of complications) but were less likely to be offered an MIS approach or undergo sentinel lymph node mapping. This may reflect that the Black women with EC in this dataset already overcame a major barrier to care by obtaining access to an SGO-COR center and likely a gynecologic oncologist. The disparity in MIS and sentinel node assessment may reflect the more advanced-stage and aggressive histologies noted in BW relative to WW, but provider biases resulting in this difference should also be addressed. This study is limited by an under-representation of Black patients relative to the general US population.

Outcome of Patients with High-Risk Endometrial Cancer Undergoing Sentinel Lymph Node Assessment versus Full Lymphadenectomy (070)

Objectives: Sentinel lymph node mapping and dissection (SLN) is endorsed by the National Comprehensive Cancer Network as a recommended surgical staging approach in patients diagnosed with apparent uterine-confined endometrial cancer (EC) of all histologies. While SLN has been validated for use in patients with high-risk histologies, data regarding the oncologic safety of SLN in the management of high-risk EC is limited and inconclusive. The objective of this study was to determine the 3-year progression-free survival (PFS) and overall survival (OS) in patients with high-risk EC who underwent SLN compared to patients who underwent pelvic ± para-aortic lymphadenectomy (LND). Methods: All patients in our healthcare system diagnosed with EC with no radiologic evidence of extra-uterine disease who underwent surgical management between January 1, 2014, and September 1, 2020, were identified, and follow-up data were recorded. SLN was performed in accordance with evidence-based practice, and an SLN algorithm was used. High-risk EC was classified based on hysterectomy specimen pathology demonstrating non-endometrioid histology or FIGO grade 3 endometrioid histology. Patients were excluded if they had more than one primary cancer at the time of diagnosis or if no follow-up records were available. Patients were categorized based on intention to treat. All statistical analyses were performed using SAS version 9.4. Conclusions: Patients with high-risk EC who underwent SLN had no difference in 3-year survival relative to LND; however, the SLN group experienced shorter unadjusted OS. When adjusting for age, adjuvant therapy, and surgical approach, the two methods were found to be similar, with a trend towards worse OS for those who underwent SLN. A randomized control trial comparing SLN versus LND with long-term follow-up for patients with EC of high-risk histologies is necessary. Objectives: Sentinel lymph node mapping and dissection (SLN) is endorsed by the National Comprehensive Cancer Network as a recommended surgical staging approach in patients diagnosed with apparent uterine-confined endometrial cancer (EC) of all histologies. While SLN has been validated for use in patients with high-risk histologies, data regarding the oncologic safety of SLN in the management of high-risk EC is limited and inconclusive. The objective of this study was to determine the 3-year progression-free survival (PFS) and overall survival (OS) in patients with high-risk EC who underwent SLN compared to patients who underwent pelvic ± para-aortic lymphadenectomy (LND). Methods: All patients in our healthcare system diagnosed with EC with no radiologic evidence of extra-uterine disease who underwent surgical management between January 1, 2014, and September 1, 2020, were identified, and follow-up data were recorded. SLN was performed in accordance with evidence-based practice, and an SLN algorithm was used. High-risk EC was classified based on hysterectomy specimen pathology demonstrating non-endometrioid histology or FIGO grade 3 endometrioid histology. Patients were excluded if they had more than one primary cancer at the time of diagnosis or if no follow-up records were available. Patients were categorized based on intention to treat. All statistical analyses were performed using SAS version 9.4. Conclusions: Patients with high-risk EC who underwent SLN had no difference in 3-year survival relative to LND; however, the SLN group experienced shorter unadjusted OS. When adjusting for age, adjuvant therapy, and surgical approach, the two methods were found to be similar, with a trend towards worse OS for those who underwent SLN. A randomized control trial comparing SLN versus LND with long-term follow-up for patients with EC of high-risk histologies is necessary.