Incidence and outcome of occult uterine sarcoma: A multi-centre study of 18604 operations performed for presumed uterine leiomyoma

Differentiating Uterine Sarcoma From Atypical Leiomyoma on Preoperative Magnetic Resonance Imaging Using Logistic Regression Classifier: Added Value of Diffusion-Weighted Imaging-Based Quantitative Parameters

OBJECTIVE

To evaluate the added value of diffusion-weighted imaging (DWI)-based quantitative parameters to distinguish uterine sarcomas from atypical leiomyomas on preoperative magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A total of 138 patients (age, 43.7 ± 10.3 years) with uterine sarcoma (n = 44) and atypical leiomyoma (n = 94) were retrospectively collected from four institutions. The cohort was randomly divided into training (84/138, 60.0%) and validation (54/138, 40.0%) sets. Two independent readers evaluated six qualitative MRI features and two DWI-based quantitative parameters for each index tumor. Multivariable logistic regression was used to identify the relevant qualitative MRI features. Diagnostic classifiers based on qualitative MRI features alone and in combination with DWI-based quantitative parameters were developed using a logistic regression algorithm. The diagnostic performance of the classifiers was evaluated using a cross-table analysis and calculation of the area under the receiver operating characteristic curve (AUC).

RESULTS

Mean apparent diffusion coefficient value of uterine sarcoma was lower than that of atypical leiomyoma (mean ± standard deviation, 0.94 ± 0.30 10-3 mm²/s vs. 1.23 ± 0.25 10-3 mm²/s; P < 0.001), and the relative contrast ratio was higher in the uterine sarcoma (8.16 ± 2.94 vs. 4.19 ± 2.66; P < 0.001). Selected qualitative MRI features included ill-defined margin (adjusted odds ratio [aOR], 17.9; 95% confidence interval [CI], 1.41-503, P = 0.040), intratumoral hemorrhage (aOR, 27.3; 95% CI, 3.74-596, P = 0.006), and absence of T2 dark area (aOR, 83.5; 95% CI, 12.4-1916, P < 0.001). The classifier that combined qualitative MRI features and DWI-based quantitative parameters showed significantly better performance than without DWI-based parameters in the validation set (AUC, 0.92 vs. 0.78; P < 0.001).

CONCLUSION

The addition of DWI-based quantitative parameters to qualitative MRI features improved the diagnostic performance of the logistic regression classifier in differentiating uterine sarcomas from atypical leiomyomas on preoperative MRI.

Population-based study of the reproductive risk factors for transvaginal ultrasound diagnosed uterine fibroids in Nigerian women

There has been no previous systematic, epidemiological study of the reproductive risk factors for uterine fibroids (UF) in African populations despite African women having the highest burden of UF in the world. Improved knowledge of the associations between UF and reproductive factors would contribute to better understanding of the etiology of UF and may suggest novel opportunities for prevention and therapeutic interventions. We used nurse administered questionnaires to survey the demographic and reproductive risk factors of UF among 484 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria, and who had transvaginal ultrasound diagnosis (TVUS). We used logistic regression models to the evaluate associations between reproductive risk factors and UF, adjusted for significant covariates. In our multivariable logistic regression models, we found inverse associations with number of children (OR = 0.83, 95%CI = 0.74-0.93, p-value = 0.002), parity (OR = 0.41, 95%CI = 0.24-0.73, p-value = 0.002), history of any type of abortion (OR = 0.53, 95%CI = 0.35-0.82, p-value = 0.004), duration of use of Depot Medroxyprogesterone Acetate (DMPA) (p-value for trend = 0.02), menopausal status (OR = 0.48, 95%CI = 0.27-0.84, p-value = 0.01), and a non-linear positive association with age (OR = 1.04, 95%CI = 1.01-1.07, p-value = 0.003). Other reproductive risk factors that have been reported in other populations (age at menarche and menopause, and oral contraceptives) were not associated with UF in this study. Our study confirms some of the reproductive risk factors for UF that have been found in other populations and shows that some of them are stronger in the Nigerian population. The associations we found with DMPA suggest opportunities for further research to understand the mechanisms of action of progesterone and its analogues in the etiology of UF, their potential use for prevention and treatment of UF.

Validation of self-report of uterine fibroid diagnosis using a transvaginal ultrasound scan

Self-report of uterine fibroids (UF) has been used for epidemiologic research in different environments. Given the dearth of studies on the epidemiology of UF in Sub-Saharan Africa (SSA), it is valuable to evaluate its performance as a potential tool for much needed research on this common neoplasm in SSA women. We conducted a cross-sectional study of self-report of UF compared with transvaginal ultrasound diagnosis (TVUS) among 486 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria. We used log-binomial regression models to compute the classification, sensitivity, specificity, and predictive values of self-report compared to TVUS, adjusted for significant covariates. The prevalence of UF on TVUS was 45.1% (219/486) compared to 5.4% (26/486) based on self-report of abdominal ultrasound scan and 7.2% (35/486) based on report of healthcare practitioner's diagnosis. Self-report correctly classified 39.5% of the women compared to TVUS in multivariable adjusted models. The multivariable adjusted sensitivity of self-report of healthcare worker diagnosis was 38.8%, specificity was 74.5%, positive predictive value (PPV) was 55.6%, and negative predictive value (NPV) was 59.8%. For self-reported abdominal ultrasound diagnosis, the multivariable adjusted sensitivity was 40.6%, specificity was 75.3%, PPV was 57.4%, and NPV was 60.6%. Self-report significantly underestimates the prevalence of UF and is not accurate enough for epidemiological research on UF. Future studies of UF should use population-based designs and more accurate diagnostic tools such as TVUS.

Population-based study of the reproductive risk factors for Transvaginal Ultrasound diagnosed Uterine Fibroids in Nigerian women

Objective

There has been no previous systematic, epidemiological study of the reproductive risk factors for uterine fibroids (UF) in African populations despite African women having the highest burden of UF in the world. Improved knowledge of the associations between UF and reproductive factors would contribute to better understanding of the etiology of UF and may suggest novel opportunities for prevention and therapeutic interventions.

Design

We used nurse administered questionnaires to survey the demographic and reproductive risk factors of UF among 484 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria, and who had transvaginal ultrasound diagnosis (TVUS). We used logistic regression models to the evaluate associations between reproductive risk factors and UF, adjusted for significant covariates.

Results

In our multivariable logistic regression models, we found inverse associations with number of children (OR = 0.83, 95%CI = 0.74-0.93, p-value = 0.002), parity (OR = 0.41, 95%CI = 0.24-0.73, p-value = 0.02), history of any type of abortion (OR = 0.53, 95%CI = 0.35-0.82, p-value = 0.004), duration of use of Depot Medroxyprogesterone Acetate (DMPA) (p-value for trend = 0.02), menopausal status (OR = 0.48, 95%CI = 0.27-0.84, p-value = 0.01), and a non-linear positive association with age (OR = 1.04, 95%CI = 1.01-1.07, p-value = 0.003). Other reproductive risk factors that have been reported in other populations (age at menarche and menopause, and oral contraceptives) were not associated with UF in this study.

Conclusion

Our study confirms the reproductive risk factors for UF that have been found in other populations and shows that some of them are stronger in the Nigerian population. The associations we found with DMPA suggest opportunities for further research to understand the mechanisms of action of progesterone and its analogues in the etiology of UF, their potential use for prevention and treatment of UF.

Epidemiology of uterine fibroid in black African women: a systematic scoping review

OBJECTIVE

Studies, mainly from high-income countries, suggest that there are ethnic and racial variations in prevalence of uterine fibroids (UF). However, there have been few studies of the epidemiology of UF in sub-Saharan Africa (SSA). We reviewed published articles on the epidemiology of UF in SSA.

DESIGN

This was a scoping review of literature.

SETTINGS

We searched three databases (PubMed, African Wide Information (EBSCO) and African Journals OnLine (AJOL)). The search for eligible articles was conducted between December 2019 and January 2021.

PRIMARY AND SECONDARY OUTCOME MEASURES

To describe the reported prevalence/incidence of, and risk factors for UF in SSA.

RESULTS

Of the 1052 articles retrieved, 9 met the inclusion criteria for review. The articles were from Nigeria (4/9), Ghana (2/9), Cameroon (1/9), Kenya (1/9) and South Africa (1/9). Two studies from pathology departments and three studies from radiology departments reported prevalence of UF. We did not find any study on the incidence or genomics of UF in SSA. Of the three studies that reported on the risk factors of UF, only one case-control study that was conducted using retrospective data of attendees at a gynaecological clinic conducted multivariable analysis.

CONCLUSION

There is lack of robust epidemiological studies of the prevalence, incidence and risk factors of UF in SSA. There is urgent need to study epidemiological and genomics risk factors of UF in SSA because UF is the most common gynaecological neoplasm in this population where it is associated with significant morbidity and occasional, usually perioperative, mortality.

Advances in the Preoperative Identification of Uterine Sarcoma

Simple Summary

As a lethal malignant tumor, uterine sarcomas lack specific diagnostic criteria due to their similar presentation with uterine fibroids, clinicians are prone to make the wrong diagnosis or adopt incorrect treatment methods, which leads to rapid tumor progression and increased metastatic propensity. In recent years, with the improvement of medical level and awareness of uterine sarcoma, more and more studies have proposed new methods for preoperative differentiation of uterine sarcoma and uterine fibroids. This review outlines the up-to-date knowledge about preoperative differentiation of uterine sarcoma and uterine fibroids, including laboratory tests, imaging examinations, radiomics and machine learning-related methods, preoperative biopsy, integrated model and other relevant emerging technologies, and provides recommendations for future research.

Abstract

Uterine sarcomas are rare malignant tumors of the uterus with a high degree of malignancy. Their clinical manifestations, imaging examination findings, and laboratory test results overlap with those of uterine fibroids. No reliable diagnostic criteria can distinguish uterine sarcomas from other uterine tumors, and the final diagnosis is usually only made after surgery based on histopathological evaluation. Conservative or minimally invasive treatment of patients with uterine sarcomas misdiagnosed preoperatively as uterine fibroids will shorten patient survival. Herein, we will summarize recent advances in the preoperative diagnosis of uterine sarcomas, including epidemiology and clinical manifestations, laboratory tests, imaging examinations, radiomics and machine learning-related methods, preoperative biopsy, integrated model and other relevant emerging technologies.

Morcellation in gynecology: short review and suggestions from Turkish Society of Minimally Invasive Gynecologic Oncology

Morcellation allows the removal of a large uterus and fibroids through small incisions with minimally invasive surgery. It helps to prevent the complications associated with large incisions in both hysterectomy and myomectomy operations. Currently, there is much debate regarding the use of power morcellation in laparoscopic hysterectomy and myomectomy, mainly due to the risk of peritoneal dissemination of undiagnosed uterine sarcomas. Unfortunately, there is no valid pre-operative diagnostic method that can differentiate sarcomas from myomas, and the currently available scientific literature regarding morcellation is insufficient. As the Turkish Society of Minimally Invasive Gynecological Oncology, we present our consensus opinion and suggestions for the preoperative evaluation and morcellation of fibroids, in line with the recent literature.

Differences in gynecologic tumor development in Amhr2-Cre mice with KRASG12D or KRASG12V mutations

How different KRAS variants impact tumor initiation and progression in vivo has not been thoroughly examined. We hypothesize that the ability of either KRAS^G12D or KRAS^G12V mutations to initiate tumor formation is context dependent. Amhr2-Cre mice express Cre recombinase in tissues that develop into the fallopian tubes, uterus, and ovaries. We used these mice to conditionally express either the KRAS^G12V/+or KRAS^G12D/+ mutation. Mice with the genotype Amhr2-Cre Pten^(fl/fl) Kras^G12D/+(G12D mice) had abnormal follicle structures and developed low-grade serous ovarian carcinomas with 100% penetrance within 18 weeks. In contrast, mice with the genotype Amhr2-Cre Pten^(fl/fl) Kras^G12V/+ (G12V mice) had normal follicle structures, and about 90% of them developed uterine tumors with diverse histological features resembling those of leiomyoma and leiomyosarcoma. Granulosa cell tumors also developed in G12V mice. Differences in cell-signaling pathways in the uterine tissues of G12D and G12V mice were identified using RNA sequencing and reverse-phase protein array analyses. We found that CTNNB1, IL1A, IL1B, TNF, TGFB1, APP, and IL6 had the higher activity in G12V mice than in G12D mice. These mouse models will be useful for studying the differences in signaling pathways driven by Kras^G12V/+ or Kras^G12D/+ mutations to aid development of targeted therapies for specific KRAS mutant variants. Our leiomyoma model driven by the Kras^G12V/+ mutation will also be useful in deciphering the malignant progression from leiomyoma to leiomyosarcoma.

Does iatrogenic tumor rupture during surgery have prognostic implications for the outcome of uterine sarcomas?

OBJECTIVE

Tumor rupture during surgery is a risk factor for recurrence of sarcomas in other locations. However, the independent impact of rupture on prognosis is uncertain in uterine sarcomas. The aim of this study was to evaluate whether uterine rupture impacts outcomes in patients with uterine sarcoma.

METHODS

A retrospective analysis was carried out of all consecutive patients with uterine sarcoma managed at the Department of Gynecology and Obstetrics of the Complejo Hospitalario Universitario Insular-Materno Infantil of the Canary Islands, Spain between January 1990 and December 2016. Inclusion criteria included all patients with histologically proven uterine sarcoma. Exclusion criteria included patients with endometrial carcinoma (non-sarcomatous) and carcinosarcomas. During this period, 1981 patients were diagnosed with a uterine malignancy; 1799 were excluded because of a diagnosis of endometrial carcinoma and 85 patients were excluded for a diagnosis of carcinosarcoma. Thus, the final sample included 97 patients with uterine sarcoma (4.9%). These included leiomyosarcoma, endometrial stromal sarcoma, adenosarcoma, and liposarcoma. Surgical resection was the primary treatment, including open, laparoscopic and vaginal surgery. Survival rates were analyzed using the Kaplan-Meier method.

RESULTS

The median age was 52 years (range 25-90); 49.5% (48) were pre-menopausal. Distribution per histological type was: 46.4% (45) leiomyosarcoma, 23.7% (23) high-grade endometrial stromal sarcoma, 17.5% (17) low-grade endometrial stromal sarcoma, 11.3% (11) adenosarcoma, and 1% (1) liposarcoma. Uterine leiomyoma was the most frequent pre-operatively suspected diagnosis (49.5%). Iatrogenic rupture of the tumor during surgery occurred in 25.3% of cases (23). International Federation of Gynecology and Obstetrics stages I-II and III-IV were identified in 74.2% (72) and 25.8% (25) of patients, respectively. The median tumor size was 8 cm (range 2-40). The recurrence rate was 47.8% (11) for patients with intra-operative tumor rupture and 25% (17) for patients without uterine rupture (p=0.03). Disease-free survival rates at 1, 2, and 5 years for patients with uterine rupture were 72.7%, 55.4%, and 13.9%, respectively, with a median time of 39 months (95% CI 2.9 to 75). For those patients without uterine rupture, disease-free survival rates at 1, 2, and 5 years were 84.8%, 76.1%, and 71.3%, respectively, with a mean time of 208.6 months (95% CI 169 to 248.3) (p=0.01). Multivariate analysis showed that stage, histological type, and iatrogenic tumor rupture during surgery were all independent prognostic factors for overall survival (OR 7.9, 95% CI 1.6 to 38.2, p=0.01); OR 5.3, 95% CI 2.1 to 13, p<0.0001; and OR 2.6, 95% CI 1.1 to 6.5, respectively, p=0.03).

CONCLUSION

Considering that uterine sarcomas, especially leiomyosarcomas, often occur in pre-menopausal women as bulky tumors requiring laparotomy and that they are rarely diagnosed pre-operatively, efforts should be made to avoid iatrogenic uterine rupture during surgery as it impairs patient survival.