The second National Institutes of Health International Congress on advances in uterine leiomyoma research: conference summary and future recommendations

Risk of uterine leiomyomata with menstrual and reproductive factors in premenopausal women: Korea nurses' health study

BACKGROUND

Uterine leiomyomata (UL) are benign smooth muscle tumors that may cause significant morbidity in women of reproductive age. This study aimed to investigate the relationship of menstrual and reproductive factors with the risk of UL in premenopausal women.

METHODS

This prospective study included 7,360 premenopausal women aged 22-48 years who were part of the Korea Nurses' Health Study. Information on the menstrual cycle and reproductive history was assessed between 2014 and 2016, and self-reported cases of UL were obtained through 2021. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

During 32,072 person-years of follow-up, 447 incident cases of UL were reported. After adjusting for other risk factors, women with late age at menarche had a lower incidence of UL (≥ 16 vs. 12-13 years: HR 0.68; 95% CI 0.47-0.99; p for trend = 0.026). The risk of UL was inversely associated with current menstrual cycle length (≥ 40 or too irregular to estimate vs. 26-31 days: HR 0.40; 95% CI 0.24-0.66) and cycle length at ages 18-22 years (HR 0.45; 95% CI 0.31-0.67; p for trend < 0.001, each). Parous women had lower risk of UL than nulliparous women (HR 0.40; 95% CI 0.30-0.53) and women who were aged 29-30 years at first birth had a lower risk of UL than those who were aged ≤ 28 years at first birth (HR 0.58; 95% CI 0.34-0.98). There was no significant association of the number of births or breastfeeding with the risk of UL among parous women. Neither a history of infertility nor oral contraceptive use was associated with the risk of UL.

CONCLUSIONS

Our results suggest that age at menarche, menstrual cycle length, parity, and age at first birth are inversely associated with the risk of UL in premenopausal Korean women. Future studies are warranted to confirm the long-term effects of menstrual and reproductive factors on women's health.

Preliminary study on ultrasound-guided high-intensity focused ultrasound ablation for treatment of broad ligament uterine fibroids

OBJECTIVE

To investigate the feasibility, efficacy and safety of ultrasound-guided high-intensity focused ultrasound (HIFU) ablation for treating the broad ligament uterine fibroid (BLUF).

METHODS

A total of 236 patients with symptomatic uterine fibroids were enrolled and treated with JC-200 extracorporeal ultrasound-guided HIFU under conscious sedation between January 2017 and December 2018. Of them, data of 12 patients with 13 broad ligament fibroids were retrospectively analyzed. The patients' mean age was 38.6 ± 6.3 years. The focused ultrasound target was deployed and moved from the deeper layer to the superficial layer of BLUFs. All patients underwent contrast-enhanced MRI (CE-MRI) before, immediate post-operation, and six months after the HIFU ablation procedure. The fibroid size, non-perfusion volume (NPV) ratio, the reduction of fibroid volumes, adverse events, symptom changes, and abnormal MRI findings associated with the HIFU treatment were analyzed.

RESULTS

Ultrasound-guided HIFU ablation in the twelve patients was technically successful with one session treatment. The mean longest diameter of BLUFs was 6.2 ± 2.3 cm. The mean NPV ratio of fibroids was 84.08%± 9.4%. After HIFU ablation, lower abdominal pain occurred in 7 cases, sacrococcygeal pain in 3 cases, and mild skin pain in 6 cases. There were no severe adverse events and complications associated with the treatment. At 6 months post-treatment follow-up, the mean fibroid volume decreased by 56.2%± 9.0% (p < 0.05), and the symptoms related to broad ligament fibroids were improved or disappeared.

CONCLUSIONS

Ultrasound-guided high-intensity focused ultrasound ablation is feasible, effective, and safe for treating broad ligament fibroids.

New and Emerging Applications of Magnetic Resonance Elastography of Other Abdominal Organs

Increasing clinical experience and ongoing research in the field of magnetic resonance elastography (MRE) is leading to exploration of its applications in other abdominal organs. In this review, the current research progress of MRE in prostate, uterus, pancreas, spleen, and kidney will be discussed. The article will describe patient preparation, modified technical approach including development of passive drivers, modification of sequences, and inversion. The potential clinical application of MRE in the evaluation of several disease processes affecting these organs will be discussed. In an era of increasing adoption of multiparametric magnetic resonance imaging approaches for solving complex abdominal problems, abdominal MRE as a biomarker may be seamlessly incorporated into a standard magnetic resonance imaging examination to provide a rapid, reliable, and comprehensive imaging evaluation at a single patient appointment in the future.

Uterine fibroids: correlations between MRI appearance and stiffness via magnetic resonance elastography

RATIONALE AND OBJECTIVES

Magnetic resonance elastography has proven to be a valuable tool in the diagnosis of liver fibrosis, breast and cervical cancer, but its application in uterine fibroids requires further characterization. The aim of the present study was to examine the relationship between uterine fibroid stiffness by MRE and MR imaging characteristics.

MATERIALS AND METHODS

An IRB-approved, HIPAA compliant review was performed of prospectively collected pelvic MRI and 2D-MRE data in patients with symptomatic uterine fibroids (N = 102). T1 and T2 weighted pelvic MRI with gadolinium enhancement were performed. In a small patient subset, fibroid stiffness was assessed by both 2D and 3D MRE. Fibroid stiffness by modality or imaging characteristics was analyzed using one-way analysis of variance followed by Student t test.

RESULTS

Four fibroid groups were identified based on T2 appearance: Isointense (N = 7), bright (N = 6), dark with minimal heterogeneity (N = 69), and dark with substantial heterogeneity (N = 20). Mean fibroid stiffness was 4.81 ± 2.12 kPa. Comparison of fibroid stiffness by T2 signal intensity showed that T2 bright fibroids were significantly less stiff than fibroids appearing T2 dark with minimal heterogeneity (mean stiffness difference = 2.38 kPa; p < 0.05) and T2 dark fibroids with substantial heterogeneity were significantly less stiff than T2 dark fibroids with minimal heterogeneity (mean difference = 1.25 kPa; p < 0.05). There was no significant association between fibroid stiffness and T1 signal characteristics or gadolinium enhancement. There was no significant difference in stiffness values obtained by either 2D vs. 3D MRE.

CONCLUSIONS

These data suggest differences in fibroid stiffness are associated with different T2 imaging characteristics with less stiff fibroids being T2 bright and more stiff fibroids being T2 dark. Further studies are needed to determine if fibroid stiffness by MRE may serve as an imaging biomarker to help predict MR-guided treatment response.

Feasibility, Safety, and Efficacy of Accurate Uterine Fibroid Ablation Using Magnetic Resonance Imaging-Guided High-Intensity Focused Ultrasound With Shot Sonication

The aim of this study was to investigate the feasibility, safety, and efficacy of uterine fibroid treatment using magnetic resonance imaging (MRI)-guided high-intensity focused ultrasound (US) with shot sonication for accurate ablation. Forty-three patients with 51 symptomatic uterine fibroids were treated with MRI-guided high-intensity focused US with shot sonication, which was a small acoustic focus of higher intensity with a shorter time (2 seconds) of US exposure and a shorter cooling time (2-3 seconds). The treatment efficacy and adverse events were analyzed, and the changes in the severity of symptoms and the reduction in fibroid volume were assessed 3 and 6 months after the procedure. All patients were successfully treated in a single session, without major complications, and the mean nonperfused volume ratio ± SD was 84.3% ± 15.7% (range, 33.8%-100%).Complete ablation was achieved in 13 T2-hypointense fibroids from 10 patients, and partial ablation was achieved in 38 fibroids from 33 patients. The overall mean treatment time was 135.0 ± 50.9 minutes (2.2 ± 0.8 hours). The transformed symptom severity scores and mean fibroid volumes decreased significantly after treatment (P < .05). In conclusion, MRI-guided high-intensity focused US with shot sonication is a feasible, safe, and effective technique for ablation of uterine fibroids and complete ablation of T2-hypointense fibroids.

Proceedings from the Third National Institutes of Health International Congress on Advances in Uterine Leiomyoma Research: comprehensive review, conference summary and future recommendations

BACKGROUND Uterine fibroids are the most common gynecologic tumors in women of reproductive age yet the etiology and pathogenesis of these lesions remain poorly understood. Age, African ancestry, nulliparity and obesity have been identified as predisposing factors for uterine fibroids. Symptomatic tumors can cause excessive uterine bleeding, bladder dysfunction and pelvic pain, as well as associated reproductive disorders such as infertility, miscarriage and other adverse pregnancy outcomes. Currently, there are limited noninvasive therapies for fibroids and no early intervention or prevention strategies are readily available. This review summarizes the advances in basic, applied and translational uterine fibroid research, in addition to current and proposed approaches to clinical management as presented at the 'Advances in Uterine Leiomyoma Research: 3rd NIH International Congress'. Congress recommendations and a review of the fibroid literature are also reported. METHODS This review is a report of meeting proceedings, the resulting recommendations and a literature review of the subject. RESULTS The research data presented highlights the complexity of uterine fibroids and the convergence of ethnicity, race, genetics, epigenetics and environmental factors, including lifestyle and possible socioeconomic parameters on disease manifestation. The data presented suggest it is likely that the majority of women with uterine fibroids will have normal pregnancy outcomes; however, additional research is warranted. As an alternative to surgery, an effective long-term medical treatment for uterine fibroids should reduce heavy uterine bleeding and fibroid/uterine volume without excessive side effects. This goal has not been achieved and current treatments reduce symptoms only temporarily; however, a multi-disciplined approach to understanding the molecular origins and pathogenesis of uterine fibroids, as presented in this report, makes our quest for identifying novel targets for noninvasive, possibly nonsystemic and effective long-term treatment very promising. CONCLUSIONS The Congress facilitated the exchange of scientific information among members of the uterine leiomyoma research and health-care communities. While advances in research have deepened our knowledge of the pathobiology of fibroids, their etiology still remains incompletely understood. Further needs exist for determination of risk factors and initiation of preventive measures for fibroids, in addition to continued development of new medical and minimally invasive options for treatment.

Self-reported family history of leiomyoma: not a reliable marker of high risk

PURPOSE

To examine the importance of self-reported family history of uterine leiomyoma (fibroids) as a marker of risk.

METHODS

Women, aged 35 to 49, were randomly selected from the membership of a large, urban health plan. Participants completed a self-administered questionnaire about family history of fibroids. Ultrasound screening for fibroids followed, regardless of whether participants had been previously diagnosed (660 black, 412 white). Data for each ethnic group were analyzed separately using Poisson regression.

RESULTS

In both ethnic groups, women who reported a family history of fibroids had an elevated risk of fibroids compared with those without family history. However, no elevated risk was apparent for cases who did not know they had fibroids when they reported the family history information.

CONCLUSIONS

Many women may first learn about their family history of fibroids when discussing their own clinical diagnosis with family members. Such bias would invalidate self-reported family history as a predictor of fibroid risk. As new pharmacologic treatments for fibroids are developed, women at high risk of fibroids would benefit from early screening and pharmacologic treatment to delay development of large fibroids and reduce the need for invasive treatments. Self-reported family history is not useful for identifying high-risk women.

Diameter of dominant leiomyoma is a possible determinant to predict coexistent endometriosis

OBJECTIVE

To identify the frequency and assess risk factors for unexpected discovery of peritoneal endometriotic implants in patients who underwent myomectomy or hysterectomy for symptomatic uterine leiomyomas.

STUDY DESIGN

We retrospectively collected medical records of 829 patients with symptomatic leiomyomas in The University of Tokyo Hospital. All the patients underwent abdominal or laparoscopic surgeries between January 2001 and December 2010 and the presence or absence of endometriosis during surgery was analyzed. Possible determinant to predict coexistent endometriosis was statistically investigated.

RESULTS

In total, 105 leiomyoma cases (12.7% in 829 patients) were diagnosed with endometriosis. Patients with small dominant leiomyomas were significantly complicated by peritoneal endometriotic implants (small leiomyomas were classified as < 8 cm). The patients with both diagnoses were more likely to be infertile and at age 39 years or younger than those with leiomyoma alone.

CONCLUSIONS

Women undergoing myomectomy or hysterectomy with both endometriosis and leiomyomas have several different clinical features compared with women with only leiomyomas. The size of largest leiomyoma may provide an important clue for coexistent endometriosis. Women with substantial infertility despite a smaller leiomyomas burden may be more likely to have a surgical indication for concomitant endometriosis.

Laparoscopic transient uterine artery occlusion and myomectomy for symptomatic uterine myoma

OBJECTIVE

To compare clinical outcomes of laparoscopic transient uterine artery ligation plus myomectomy (LTUAL) to simple laparoscopic myomectomy (LM) for symptomatic myomas.

DESIGN

Comparative observational study.

SETTING

Medical centers.

PATIENT(S)

One hundred sixty-seven patients with symptomatic myomas.

INTERVENTION(S)

Eighty-four patients underwent LTUAL and LM; 83 patients underwent LM only.

MAIN OUTCOME MEASURE(S)

Operative time, blood loss, gonadal hormone level, uterine artery resistance index, menorrhea, pregnancy rate, and recurrence rate of myoma.

RESULT(S)

The intraoperative blood loss in the LTUAL group was lower than in the LM group. The menstrual blood volume (MBV) and the menstrual period of the LTUAO group was unchanged after operation relative to the prediseased volume. No significant difference was found in the resistance index of the uterine artery blood flow, the recurrence rate, and the fertility rate between the LTUAL and LM groups.

CONCLUSION(S)

LTUAL and LM are a promising surgical treatment for symptomatic uterine myoma and did not produce any appreciable adverse effect on fertility.

New directions in the epidemiology of uterine fibroids

Although uterine leiomyomata (fibroids) have been the leading indication for hysterectomy in the United States for decades, the epidemiological data on fibroid prevalence and risk factors are limited. Given the hormonal dependence of fibroids, most earlier studies focused on reproductive or hormonal factors. Recent analyses have extended that focus to other areas. We present previously unpublished data on the association between reproductive tract infections and fibroids that highlight the need for more detailed studies. Our review suggests that metabolic, dietary, stress, and environmental factors may also play a role in fibroid development.