The prognostic significance of lower uterine segment involvement in surgically staged endometrial cancer patients with negative nodes

Effect of low uterine segment involvement on prognosis of early stage endometrial cancer

AIM

Our aim is to investigate the effect of uterine lower segment involvement on prognosis of early-stage endometrial cancer cases diagnosed and treated in our clinic.

MATERIALS AND METHODS

The file records of 316 cases reviewed retrospectively.Only stage I (a and b, n=209) cases were investigated, because they were more homogeneous group.

RESULTS

The lymphovascular invasion rate was found to be higher in patients with stage Ia and uterine lower segment involvement (p < 0.001). Adjuvant treatment requirement was higher in patients with stage Ia and uterine lower segment involvement (p < 0.001). Among stage Ia cases, the recurrence rate between 1 and 3 years was found to be higher in cases with uterine lower segment involvement (p = 0.001). Among the stage Ib cases, lymphovascular invasion was found to be higher in cases with uterine lower segment involvement (p < 0.001). The recurrence rate between 1 and 3 years was found to be higher in stage Ib compared to Ia (p = 0.01). Uterine lower segment involvement was found to be associated with high lymphovascular invasion rate in all stage I cases (p < 0.001). It was determined that the need for adjuvant treatment was higher in cases with uterine lower segment involvement (p < 0.001). It was determined that the probability of recurrence between 1 and 3 years was higher in cases with uterine lower segment involvement (p = 0.007).

CONCLUSION

Uterine lower segment involvement is associated with increased lymphovascular invasion even in the early stages. It is an important risk factor for systemic spread such as lymphovascular invasion, myometrial invasion, and lymph node involvement.

Range of Resection in Endometrial Cancer-Clinical Issues of Made-to-Measure Surgery

Endometrial cancer (EC) poses a significant health issue among women, and its incidence has been rising for a couple of decades. Surgery remains its principal treatment method and may have a curative, staging, or palliative aim. The type and extent of surgery depends on many factors, and the risks and benefits should be carefully weighed. While simple hysterectomy might be sufficient in early stage EC, modified-radical hysterectomy is sometimes indicated. In advanced disease, the evidence suggests that, similarly to ovarian cancer, optimal cytoreduction improves survival rate. The role of lymphadenectomy in EC patients has long been a controversial issue. The rationale for systematic lymphadenectomy and the procedure of the sentinel lymph node biopsy are thoroughly discussed. Finally, the impact of the molecular classification and new International Federation of Gynecology and Obstetrics (FIGO) staging system on EC treatment is outlined. Due to the increasing knowledge on the pathology and molecular features of EC, as well as the new advances in the adjuvant therapies, the surgical management of EC has become more complex. In the modern approach, it is essential to adjust the extent of the surgery to a specific patient, ensuring an optimal, made-to-measure personalized surgery. This narrative review focuses on the intricacies of surgical management of EC and aims at summarizing the available literature on the subject, providing an up-to-date clinical guide.

The significance of lower uterine segment involvement in endometrial cancer

BACKGROUND

Limited data suggests lower uterine segment involvement (LUSI) in endometrial cancer may be associated with other poor prognostic factors. We assessed the unclear impact of LUSI on prognosis in endometrial cancer.

METHOD

ology: A revision of pathological samples following surgical staging between the years 2002-2022 was performed and clinical data collected from patients' records. Characteristics and outcomes of women with and without LUSI were compared and analysed. Kaplan Meyer survival curves compared overall survival (OS) and progression-free survival (PFS).

RESULTS

429 women were included, of which 45 (10.5%) had LUSI. No differences were found between the groups regarding demographic or clinical characteristics. LUSI was significantly associated with lympho-vascular space invasion (40% vs. 22% p = 0.01), lymph node involvement (6.4% vs. 9.1%, p = 0.05), shorter PFS (4 vs. 5.5 years, p = 0.01) and OS (5.6 vs. 11.5 years, p = 0.03). Multivariate analysis showed higher hazard ratios for OS and PFS (1.55 95%CI 0.79-3.04 and 1.29 95%CI 0.66-2.53, respectively) but these were insignificant even in a sub-analysis of endometrioid histology (1.76 95%CI 0.89-3.46 and 1.35 95%CI 0.69-2.65, respectively). A trend towards decreased PFS and OS was demonstrated in the Kaplan Meyer survival curves for all cases (log rank test p = 0.5 and 0.29 respectively), endometrioid histology (log rank test p = 0.06 and 0.51 respectively) and early-stage disease (log rank test p = 0.63 and 0.3 respectively).

CONCLUSION

LUSI may be related to poorer outcome of endometrial cancer and may represent an additional factor to consider when contemplating adjuvant treatment, especially in endometrioid-type and early-stage disease.

Association of Lymphovascular Space Invasion (LVSI) with Histological Tumor Grade and Myometrial Invasion in Endometrial Carcinoma: A Review Study

Endometrial carcinoma is one of the most frequent gynecological cancers in developed countries. Lymphovascular space invasion (LVSI), histological grade, and myometrial invasion (MMI) are important prognostic factors of endometrial carcinoma. LVSI is considered an independent poor prognostic factor in endometrial carcinoma. Based on the importance of LVSI, this study aimed to discuss the association of LVSI with tumor grade and MMI. A search of PubMed, EMBASE, Web of Science, Scopus, Google Scholar, and Cochrane Library was carried out to collect related studies. Consequently, most studies showed that LVSI is significantly associated with higher histologic grade and deep MMI.

Predictability of lymph node involvement in uterus-confined endometrioid endometrial cancer by tumour size, pattern and location measured with transvaginal ultrasonography: can we save time?

We aimed to investigate whether transvaginal ultrasonography (TVUSG)-measured tumour size, pattern and location were significant predictors for lymph node metastasis in the uterus-confined endometrioid endometrial cancer (EEC) patients. A total of 213 patients with EEC were recruited and 73 of them were considered eligible and were analysed according to lymph node involvement. Tumour size, pattern and location measured by transvaginal ultrasound were recorded. Thereafter, patients were distributed according to their lymph node involvement and were compared with respect to these parameters. The patients' median age was 56 (27-80). Mean of the resected lymph nodes was 29.68 and 33.5 in lymph-node-negative and positive patients, respectively (p=.525). Tumour diameter was measured >2 cm on transvaginal ultrasound in 28 (48.3%) and 13 (86.7%) cases of the lymph node-negative and positive arms, respectively (p=.008). Transvaginal ultrasound revealed that 18 (31.0%) tumours in lymph node-negative and two (13.3%) in the node positive patients had polypoid pattern (p=.171). Seventeen (54.8%) tumours of the lymph node-negative group and three (42.9%) of the node positive group were determined in the lower uterine segment (p=.250). While tumour diameter measured with TVUSG was predictable for lymph node involvement in the uterus-confined EEC, its pattern and location were not.Impact StatementWhat is already known on this subject? In clinically early-stage endometrioid endometrial cancer (EEC), it has been recognised for decades that selective lymphadenectomy is a more acceptable strategy than the systematic lymphadenectomy, owing to the low rate of lymph node metastases in the patients. Preoperative imaging, frozen section and recently accepted lymph node concept are the prominent methods in designating appropriate candidates for lymphadenectomy. The measurement of tumour diameter or size obtained intraoperatively by frozen section assessment is one of the parameters used in MAYO criteria for selective lymphadenectomy in endometrial cancer patients.What do the results of this study add? In our study, tumour diameter measured with transvaginal ultrasonography was predictable for lymph node involvement in the uterus-confined EEC.What are the implications of these findings for clinical practice and/or further research? Transvaginal ultrasonography-measured tumour diameter can be considered in deciding to proceed with pelvic lymphadenectomy while waiting for the frozen section result. It should be remembered that this approach could be considered only in clinics using MAYO criteria for selective lymphadenectomy, and it needs to be confirmed with more prospective studies.

Lymphovascular space invasion in endometrial carcinoma: Tumor size and location matter

OBJECTIVE

To analyze histological factors possibly associated with lymphovascular space invasion (LVSI) and to determine which of those can act as independent surrogate markers.

METHODS

Retrospective cohort study performed between January 2001 and December 2014. LVSI was defined as the presence of tumor cells inside a space completely surrounded by endothelial cells. Risk factors evaluated included myometrial invasion, tumor grade, size, location, and cervical invasion. Univariate logistical regression models were applied to study any possible association of LVSI with these factors. Values were adjusted by multivariate logistic regression analysis.

RESULTS

A total of 327 patients with endometrial carcinoma treated in our Centre were included. LVSI was observed in 120 patients (36.7%). Lower uterine segment involvement (OR 5.21, 95% CI:2.6-10.4, p < 0.001) and size ≥2 cm (OR 2.62, 95% CI: 1.14-6.1, p < 0.001) were independent factors for LSVI in multivariate analysis. In univariate analysis, LVSI was a surrogate marker in type 1 tumors with deep myometrial invasion (IB, 51.9% vs. IA, 16.0%; p < 0.001), grade 3 (G3 55.8% vs. G1 16.2%; p < 0.001), size ≥2 cm (37.9% vs. 16.1%, p = 0.005), those with involving the lower segment of the uterus (58.9% vs. 22.5%, p < 0.001) and/or with cervical stromal invasion (65.4% vs. 26.1%, p < 0.001), and in type 2 tumors (61.5% vs. 30.5%, p < 0.001). The use of uterine manipulator did not increase the rate of LVSI (35.5% vs. 40.5%, p = 0.612) as compared to no manipulator use.

CONCLUSIONS

Size ≥2 cm and involvement of the lower uterine segment are independent factors for LSVI, in type 1 tumors, which can be used for surgical planning. LVSI is also more common in type 1 tumors with deep myometrial invasion, grade 3 and/or cervical stromal invasion, and also in type 2 tumors. The use of a uterine manipulator does not increase LVSI.

Imaging-based definition of lower uterine segment carcinoma to improve the detection sensitivity of probable Lynch syndrome

OBJECTIVE

The aim of this study was to investigate a magnetic resonance imaging-based definition of lower uterine segment carcinoma.

METHODS

We retrospectively reviewed 587 consecutive patients with endometrial cancer who underwent hysterectomy. Lower uterine segment carcinoma was determined through pathological examination and magnetic resonance imaging assessment. For imaging assessment, the location of the inner lining of the uterus was classified into four equal parts on a sagittal section image. A tumor was defined as lower uterine segment carcinoma when its thickest part was located in the second or the third part from the uterine fundus. Lower uterine segment carcinoma was further divided into lower uterine segment in a narrow sense, upon which diagnosis was exclusively based on pathological findings, and lower uterine segment in a broad sense that were the remaining lower uterine segment carcinomas except lower uterine segment carcinomas in a narrow sense. The relationship between lower uterine segment carcinoma and probable Lynch syndrome was investigated. Patients with loss of MSH2, MSH6, and PMS2 expression or those with tumors with loss of MLH1 and absence of MLH1 promoter methylation were diagnosed as probable Lynch syndrome.

RESULTS

Lower uterine segment carcinoma was identified in 59 (10.2%) patients. Twenty-eight (47.5%) patients were categorized as lower uterine segment in a narrow sense and 31 (52.5%) as lower uterine segment in a broad sense. Among them, probable Lynch syndrome was identified in 12 (20.3%) cases. There was no difference in clinical profiles, including the prevalence of probable Lynch syndrome between the two categories.

CONCLUSIONS

A magnetic resonance imaging-based expanded definition of lower uterine segment carcinoma is likely to secure characteristics equivalent to a conventional pathology-based definition of lower uterine segment carcinoma. The novel definition of lower uterine segment carcinoma might improve the detection of probable Lynch syndrome.

Is lower uterine segment involvement a prognostic factor in endometrial cancer?

BACKGROUND/AIM

The purpose of this study is to investigate the prognostic significance of lower uterine segment (LUS) involvement in endometrial cancer (EC).

MATERIALS AND METHODS

We reviewed the patients who were operated at our institution between July 2007 and March 2015 with the diagnosis of EC. Tumors localized in the corpus and involving the LUS or localized entirely in the LUS formed Group A, while tumors in the uterine corpus without LUS involvement formed Group B. Clinicopathological characteristics and survival of the patients were compared in both groups.

RESULTS

A total of 500 patients were included in the study. There were 139 patients who had tumors involving the LUS and formed Group A, while 361 patients with endometrial tumors in the uterine corpus without LUS involvement formed Group B. We did not detect a significant difference between survival of the patients in group A and group B (78 months vs. 87 months, respectively; P > 0.05).

CONCLUSION

We found that LUS involvement was not an independent prognostic factor for poor survival, but it is associated with other poor prognostic factors such as deep myometrial invasion, uterine serosal involvement, lymphovascular space invasion, lymph node metastasis and higher FIGO grade.

Overexpression of Lysine-Specific Demethylase 1 Is Associated With Tumor Progression and Unfavorable Prognosis in Chinese Patients With Endometrioid Endometrial Adenocarcinoma

OBJECTIVE

Lysine-specific demethylase 1 (LSD1) is a kind of flavin adenine dinucleotide-dependent amine oxidase that regulates normal cellular differentiation, gene activation, tumorigenesis, and progression. This study aims to detect the expression level of LSD1 in endometrial cancer and to explore its role in the progression and prognosis of endometrioid endometrial adenocarcinoma (EEA).

METHODS

Immunohistochemistry was used to examine the expression of LSD1 in 206 EEA specimens, 50 benign endometrial lesion specimens, and 45 normal endometrium specimens. χ Analysis, Kaplan-Meier method, and multivariate Cox proportional hazard analysis were applied for the statistical analysis.

RESULTS

Compared with normal endometrium and benign endometrial lesion (both P < 0.001), LSD1 was overexpressed in EEA. LSD1 expression was correlated with histological grade, International Federation of Gynecology and Obstetrics (FIGO) stage, vascular/lymphatic invasion, depth of myometrial invasion, and lymph node metastasis. Results of the Kaplan-Meier analysis indicated that LSD1 expression was associated with overall survival (OS) and disease-free survival (DFS) of EEA. The negative expression LSD1 group had longer OS and DFS than did the positive expression group. The difference was significant (both P < 0.001, log-rank test). Multivariate Cox regression analysis revealed that the LSD1 expression status was an independent prognostic factor for both OS (P = 0.027) and DFS (P = 0.016) of patients with EEA.

CONCLUSIONS

Overexpression of LSD1 may contribute to the progression of EEA and may thus serve as a new biomarker to predict the prognosis of EEA.

Development and external validation of new ultrasound-based mathematical models for preoperative prediction of high-risk endometrial cancer

OBJECTIVES

To develop and validate strategies, using new ultrasound-based mathematical models, for the prediction of high-risk endometrial cancer and compare them with strategies using previously developed models or the use of preoperative grading only.

METHODS

Women with endometrial cancer were prospectively examined using two-dimensional (2D) and three-dimensional (3D) gray-scale and color Doppler ultrasound imaging. More than 25 ultrasound, demographic and histological variables were analyzed. Two logistic regression models were developed: one 'objective' model using mainly objective variables; and one 'subjective' model including subjective variables (i.e. subjective impression of myometrial and cervical invasion, preoperative grade and demographic variables). The following strategies were validated: a one-step strategy using only preoperative grading and two-step strategies using preoperative grading as the first step and one of the new models, subjective assessment or previously developed models as a second step.

RESULTS

One-hundred and twenty-five patients were included in the development set and 211 were included in the validation set. The 'objective' model retained preoperative grade and minimal tumor-free myometrium as variables. The 'subjective' model retained preoperative grade and subjective assessment of myometrial invasion. On external validation, the performance of the new models was similar to that on the development set. Sensitivity for the two-step strategy with the 'objective' model was 78% (95% CI, 69-84%) at a cut-off of 0.50, 82% (95% CI, 74-88%) for the strategy with the 'subjective' model and 83% (95% CI, 75-88%) for that with subjective assessment. Specificity was 68% (95% CI, 58-77%), 72% (95% CI, 62-80%) and 71% (95% CI, 61-79%) respectively. The two-step strategies detected up to twice as many high-risk cases as preoperative grading only. The new models had a significantly higher sensitivity than did previously developed models, at the same specificity.

CONCLUSION

Two-step strategies with 'new' ultrasound-based models predict high-risk endometrial cancers with good accuracy and do this better than do previously developed models.

Correlation of TNFAIP8 overexpression with the proliferation, metastasis, and disease-free survival in endometrial cancer

Tumor necrosis factor alpha-induced protein 8 (TNFAIP8) is an apoptosis regulator proven to have an important function in the proliferation, invasion, metastasis, and progression of malignancies. In this study, we investigated the clinical role of TNFAIP8 overexpression in endometrial cancer (EC) and determined the relationship of TNFAIP8 with the proliferative antigen Ki-67 and metastasis-related gene matrix metallopeptidase 9 (MMP9) in 225 tumor specimens by immunohistochemistry and western blot, in order to elucidate more information on the role of TNFAIP8 protein with regard to the pathogenesis of EC. An association was observed between TNFAIP8 overexpression and clinicopathologic factors, such as advanced International Federation of Gynecology and Obstetrics stage (P<0.001), higher histologic grade (P=0.017), deep myometrial invasion (P=0.030), lymphovascular space invasion (P=0.011), lymph node metastasis (P<0.001), and recurrence. Furthermore, TNFAIP8 overexpression was strongly correlated with MMP9 and Ki-67 expression in the progression of ECs. Patients with high expression of TNFAIP8 (P<0.001 for both) and Ki-67 (P=0.007 and P=0.008) had poor overall survival and disease-free survival (DFS) rates. MMP9 overexpression did not affect survival outcomes (P>0.05). Multivariate Cox regression analysis revealed that TNFAIP8 (P=0.029) and lymph node metastasis (P=0.022) were independent factors of DFS in patients with EC. These findings suggested that TNFAIP8 may be used as a prognostic marker for the recurrence of EC, and its promotion of the proliferation and metastasis in EC may be due to its mediation of Ki-67 and MMP9.

Retrospective analysis of prognostic variables and clinical outcomes in surgically staged intermediate risk endometrial carcinoma

OBJECTIVE

To identify independent prognostic variables for surgically staged intermediate risk endometrial carcinoma as defined by the Gynecologic Oncology Group 99 (GOG99) criteria.

STUDY DESIGN

Retrospective study of 239 patients with FIGO stage IB-occult IIB endometrioid type endometrial cancer, who were primarily treated with comprehensive staging surgery. Data were collected on clinicopathological variables, extent of primary surgery, postoperative adjuvant treatment, and patterns of recurrences. Kaplan-Meier survival curves were used to estimate disease free survival (DFS) and overall survival (OS), and multivariate Cox regression models were used to identify independent prognostic variables. The median follow-up time was 67 months (range, 12-183 months).

RESULTS

The 5-year DFS and OS were 91.0% and 93.0%, respectively. On univariate Kaplan-Meier analysis, age>60 years, deep myometrial invasion (MI), presence of lymph vascular invasion (LVSI), and negative progesterone receptor (PR) status were significantly associated with diminished 5-year DFS and OS. The univariate analysis on patterns of failures demonstrated that patients with older age or positive LVSI were more inclined to develop locoregional recurrence, while PR status and the depth of MI had a statistically significant impact on distant failure. On multivariate analysis, PR status, age, and the depth of MI were independent prognostic variables for 5-year DFS, and age was the only independent prognostic variable for 5-year OS. LVSI and age were independent prognostic variables for locoregional recurrence, while PR status and depth of MI were independent prognostic variables for distant recurrence.

CONCLUSIONS

Age, depth of MI, PR status and presence of LVSI are of independent prognostic value for intermediate risk endometrial cancer. The presence of these variables warrants consideration when deciding upon treatment strategies.

Trop-2 protein overexpression is an independent marker for predicting disease recurrence in endometrioid endometrial carcinoma

Background

Endometrial cancer is the most common gynecologic malignancy in developed countries. Trop-2 is a glycoprotein involved in cellular signal transduction and is differentially overexpressed relative to normal tissue in a variety of human adenocarcinomas, including endometrioid endometrial carcinomas (EEC). Trop-2 overexpression has been proposed as a marker for biologically aggressive tumor phenotypes.

Methods

Trop-2 protein expression was quantified using tissue microarrays consisting of formalin-fixed paraffin-embedded specimens from 118 patients who underwent surgical staging from 2001–9 by laparotomy for EEC. Clinicopathologic characteristics including age, stage, grade, lymphovascular space invasion, and medical comorbidities were correlated with immunostaining score. Univariate and multivariate analyses were performed for overall survival, disease-free survival, and progression-free survival in relation to clinical parameters and Trop-2 protein expression.

Results

Clinical outcome data were available for 103 patients. Strong Trop-2 immunostaining was significantly associated with higher tumor grade (p=0.02) and cervical involvement (p<0.01). Univariate analyses showed a significant association with reduced disease-free survival (DFS) (p=0.01), and a trend towards significance for overall and progression-free survival (p=0.06 and p=0.05, respectively). Multivariate analyses revealed Trop-2 overexpression and advanced FIGO stage to be independent prognostic factors for poor DFS (p=0.04 and p <0.001, respectively).

Conclusions

Trop-2 protein overexpression is significantly associated with higher tumor grade and serves as an independent prognostic factor for DFS in endometrioid endometrial cancer.

Carcinoma of the Lower Uterine Segment (LUS): Clinicopathological Characteristics and Association with Lynch Syndrome

Endometrial cancer arises from the uterine body and fundus in many cases, but can also originate from the lower region of the uterine body through the upper region of the cervix. Such tumors are referred to as carcinoma of the lower uterine segment (LUS) or isthmus, and account for 3-6.3% of all cases of endometrial cancer. This relatively low incidence has permitted performance of only small-scale studies, but the clinical and pathological characteristics of carcinoma of the LUS in all these reports have differed from those of other endometrial cancers. Generally, endometrial cancer is classified into estrogen-dependent endometrioid adenocarcinoma (designated as type I), and non-endometrioid types that are less associated with estrogen and include poorly differentiated adenocarcinoma (type II). In some reports, carcinoma of the LUS has been found to have type II characteristics. Carcinoma of the LUS has also been associated with Lynch syndrome, a hereditary disease with frequent development of colorectal, endometrial, and ovarian cancers. Lynch syndrome is thought to be induced by mismatch repair gene mutation. The frequency of Lynch syndrome in cases of general endometrial cancer is 1-2%. In contrast, the frequency in patients with carcinoma of the LUS is much higher, with up to 29% of cases diagnosable with Lynch syndrome and a high frequency of hMSH2 mutation found in one study. This suggests that further investigation of the clinical and pathological characteristics of carcinoma of the LUS and the association with Lynch syndrome is required through performance of a large-scale survey.

Lower uterine segment involvement is associated with poor outcomes in early-stage endometrioid endometrial carcinoma

BACKGROUND

The clinicopathologic significance of lower uterine segment involvement (LUSI) in endometrial cancer patients remains unclear. Although LUSI has been reported to be a prognostic indicator, literature is limited.

METHODS

We studied 481 surgically staged endometrioid endometrial cancers with disease confined to the uterus (FIGO 1988 stage I or II). Primary outcomes were overall survival (OS) and disease-free survival (DFS). The relationships between LUSI and OS and DFS were assessed using the Kaplan-Meier method and Cox proportional hazard models. The t test or Fisher exact test was used for evaluating relationships between variables of interest.

RESULTS

LUSI was present in 223 cases (46.4%), and was associated with both decreased disease free survival (P = 0.02) and overall survival (P = 0.01) in univariate analysis. Multivariate analysis confirmed the association between LUSI and increased risk for recurrence [hazard ratio (HR) 2.27; 95% confidence interval (95% CI) 1.09-4.7; P = 0.03] and increased mortality (HR 1.76; 95% CI 1.12-2.78; P = 0.01).

CONCLUSIONS

LUSI in patients with early-stage endometrioid endometrial cancer is associated with decreased survival.

Carcinoma of the lower uterine segment: a newly described association with Lynch syndrome

PURPOSE

Endometrial carcinoma in the lower uterine segment (LUS) is a poorly described cancer that can be clinically confused with endocervical carcinoma. We performed a case-comparison study to document the clinicopathologic characteristics of LUS tumors and their association with risk factors for endometrial cancer.

PATIENTS AND METHODS

The clinical records and pathology reports from women who underwent hysterectomy at our institution for endometrial or endocervical adenocarcinoma over an 11-year interval were reviewed. The LUS group consisted of women with endometrial tumors that clearly originated between the lower uterine corpus and the upper endocervix. Immunohistochemistry and microsatellite instability and MLH1 methylation assays were performed.

RESULTS

Thirty-five (3.5%) of 1,009 women had endometrial carcinoma of the LUS. Compared with patients with corpus tumors, LUS patients were younger, had higher stage tumors, and had more invasive tumors. Preoperative diagnosis of the LUS tumors more frequently included the possibility of endocervical adenocarcinoma. Seventy-three percent of the LUS tumors had an immunohistochemical expression pattern typical of conventional endometrioid adenocarcinoma. Ten (29%) of 35 women with LUS tumors were confirmed to have Lynch syndrome or were strongly suspected to have Lynch syndrome on the basis of tissue-based molecular assays.

CONCLUSION

The prevalence of Lynch syndrome in patients with LUS endometrial carcinoma (29%) is much greater than that of the general endometrial cancer patient population (1.8%) or in endometrial cancer patients younger than age 50 years (8% to 9%). On the basis of our results, the possibility of Lynch syndrome should be considered in women with LUS tumors.