Accessory and cavitated uterine masses: a case series and review of the literature

Objectives

The purpose of this study is to report nine patients of young women who underwent a surgical treatment of an accessory and cavitated uterine mass (ACUM) in our hospital between 2014 and 2022 and review all cases described in the literature.

Material and methods

The principal outcomes measured are the imaging techniques used to determine the diagnosis, the type of surgery used and the post-operative evolution of symptoms. We also report and analyse the 79 patients found in the literature since 1996 in addition to our 9 patients.

Results

Surgical excision is the only long-lasting treatment. Small invasive surgery with laparoscopic access is the gold standard and most widely used (83.0%). Some new therapeutic procedures have been recently described of which ethanol sclerotherapy seems very promising. Post-operatively, 54.5% of patients have a complete relief of symptoms. MRI is the best imaging technique to identify ACUM. Finally, we refine the description of this pathology and give a more precise definition of it.

Conclusion

Through our literature review and the analysis of our cases, we want to underline an important diagnostic criterion of this pathology: the fallopian tube on the homolateral side of the ACUM never communicates with the latter. It is a capital element for differential diagnosis.

Accessory cavitated uterine mass (ACUM) as a miniature uterine anomaly causing severe lateralized dysmenorrhea: case series

OBJECTIVES

Our study aimed to retrospectively analyse and present the clinical course of accessory cavitated uterine mass (ACUM), a rarely diagnosed uterine malformation.

MATERIAL AND METHODS

The study group comprised 5 adolescents that were treated in the Division of Gynecology, Clinical Hospital of Obstetrics and Gynecology of Poznan University of Medical Sciences, between October 2017 and August 2022. Patients' age at diagnosis of ACUM ranged from 14.1 to 27.5 (mean 21.4) years. All patients complained of severe dysmenorrhea with significant lateralisation of the pain.

RESULTS

Pelvic ultrasound (US) followed by pelvic magnetic resonance imaging (MRI) revealed the presence of a small cystic lesion surrounded by a ring of myometrium within or in connection with the regular uterine body. In four patients (80%), the lesion was on the right side, and in one patient (20%) on the left side. The volume of the ACUM cavity ranged from 0.04 to 2.4 (mean 0.8) cm³. Laparoscopic excision of ACUM, located near the uterine attachment of the round ligament, was performed in all five cases and resulted in the complete resolution of symptoms. None of the patients was diagnosed with adenomyosis or pelvic endometriosis.

CONCLUSIONS

ACUM is a small, surgically correctable cause of severe dysmenorrhea in young females with an otherwise normal uterus. The lateralisation of the menstrual pain should prompt the search for this malformation with imaging techniques (US, MRI). ACUM laparoscopic excision results in complete relief of symptoms. ACUM is not associated with pelvic endometriosis.

[Dysmenorrhea and pelvic pain secondary to an accessory and cavitated uterine mass]

An accessory and cavitated uterine mass (ACUM) is a rare anomaly with an embryological origin of dysfunctionning female gubernaculum. It is an accessory mass internally lined with normal endometrium, separated from the uterine cavity and located near the insertion of the round ligament. ACUM's clinical manifestations are severe dysmenorrhea and/or chronic pelvic pain. It is a relatively unknown condition, which makes its diagnosis complicated and suggests a large differential diagnosis. We report the case of a 31-year-old female presenting with pelvic chronic pain and crippling dysmenorrhea. The initial work-up consists of a magnetic resonance imaging showing an interstitial lesion possibly corresponding to an ACUM. This supposition was then confirmed by histopathology.

Imaging features of accessory cavitated uterine mass (ACUM): a peculiar yet correctable cause of dysmenorrhea

Accessory cavitated uterine mass (ACUM) is a rare form of developmental mullerian anomaly which causes chronic pelvic pain, dysmenorrhea and infertility in young females. It is a non-communicating, accessory cavity within an otherwise normal uterus, lined by functional endometrium and surrounded by myometrium-like smooth muscle cells which imparts it uterus-like appearance. USG and MRI are the imaging modalities which help in reaching the diagnosis. Knowledge of this entity and awareness of its imaging features can help diagnose this often underdiagnosed and surgically correctable cause of dysmenorrhea.

Imaging Manifestations of Accessory Cavitated Uterine Mass-A Rare Mullerian Anomaly

Context  Accessory cavitated uterine mass (ACUM) is an uncommon and under-recognized entity with distinct imaging characteristics and causing significant patient distress. Differentiating it from its other clinical and radiological differentials is therefore extremely important and prevents delay in surgical management which is the treatment of choice.

Aims  The aim of the study is to describe the MRI appearance of the surgically and pathologically proven ACUM cases from our institution in the last 2 years.

Settings and Design  This is a retrospective study in a tertiary care hospital in South India.

Methods and Material  We reviewed the clinical presentations and imaging findings of seven surgically proven cases of ACUM qualifying the proposed diagnostic criteria.

Results  All patients presented with chronic pelvic pain, dysmenorrhea, and prolonged post-menstrual pain. MRI in all seven cases showed an intramural, noncommunicating, and cavitating lesion near the uterine cornua with internal contents similar to that of endometrioma. Although the cavity was lined by endometrium in all the cases (proven in pathology), it was well appreciable on MRI in only five cases. The rest of the uterine myometrium and main endometrial cavity were normal with no features of adenomyosis.

Conclusion  MRI is a reliable diagnostic tool for accurate diagnosis of ACUM, and more importantly, in distinguishing it from other causes of chronic pelvic pain like adenomyosis and endometriosis and other imaging differentials like adenomyoma, noncommunicating uterine horn, and degenerating leiomyoma.

Imaging in gynecological disease (21): clinical and ultrasound characteristics of accessory cavitated uterine malformations

OBJECTIVE

To describe the clinical and ultrasound characteristics of accessory cavitated uterine malformations (ACUMs).

METHODS

This was a single-center observational study of consecutive patients diagnosed with an ACUM, who had undergone an ultrasound examination by an experienced ultrasound examiner between January 2013 and May 2019, identified retrospectively from medical records. ACUM was diagnosed when a cavitated lesion with a myometrial mantle and echogenic contents was seen within the anterolateral wall of the myometrium beneath the insertion of the round ligament. In all women, presenting symptoms and clinical history were recorded along with detailed descriptions of the lesions and any concomitant pelvic abnormalities.

RESULTS

Twenty patients diagnosed with an ACUM were identified. Median age was 29.2 (interquartile range, 25.0-35.8) years. None of the women was premenarchal or postmenopausal. All of the women reported painful periods or pelvic pain and none of them reported subfertility. Twelve of the ACUMs were in the right anterolateral myometrium and eight were in the left anterolateral myometrium. Both a myometrial mantle and a fluid-filled cavity were considered to be defining features on ultrasound. The fluid contained within the cavity was either echogenic with a ground-glass appearance or hyperechoic. All of the lesions were spherical in shape. The Doppler flow seen in the outer rim was not markedly different from that of the surrounding myometrium, and the content of the cavity was avascular on Doppler examination. The mean outer cavity diameter of the ACUMs was 22.8 (95% CI, 20.9-24.8) mm and the mean internal cavity diameter was 14.1 (95% CI, 12.2-16.1) mm. Four women opted for transvaginal ultrasound-guided alcohol sclerotherapy. Surgical excision was carried out in eight cases, and the diagnosis was confirmed on histopathological examination in all of them.

CONCLUSIONS

ACUMs are a uterine abnormality with a distinct ultrasound appearance, which are associated with dysmenorrhea and chronic pelvic pain. Knowledge of their typical appearance on ultrasound could facilitate early detection and treatment. There are several treatment options for ACUM, ranging from simple analgesia to complete excision. Further prospective and longitudinal studies are required to study the prevalence and natural history of this condition. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Uterine-sparing Laparoscopic Resection of Accessory Cavitated Uterine Masses

STUDY OBJECTIVE

To demonstrate surgical techniques utilized during uterine-sparing laparoscopic resections of accessory cavitated uterine masses (ACUMs). ACUMs represent a rare uterine entity observed in premenopausal women suffering from dysmenorrhea and recurrent pelvic pain. The diagnosis is made when an isolated extra-cavitated uterine mass is resected from an otherwise normal appearing uterus with unremarkable endometrial lumen and adnexal structures. Pathologic confirmation requires an accessory cavity lined with endometrial epithelium (and corresponding glands and stroma) filled with chocolate-brown fluid. Adenomyosis must be absent. Although the origin of ACUMs is currently unknown, the most common presentation is a 2-4 cm lateral uterine wall mass at the level of the insertion of the round ligament. Hence it has been hypothesized that gubernaculum dysfunction may be responsible for duplication or persistence of paramesonephric tissue leading to ACUM formation as a new Müllerian anomaly.

DESIGN

A stepwise surgical tutorial describing 2 laparoscopic ACUM resections using a narrated video (Canadian Task Force classification III).

SETTING

An academic tertiary care hospital.

PATIENTS

In this video, we present 2 patients who underwent uterine-sparing laparoscopic resections of their ACUM in order to preserve fertility (Case 1) or avoid the complications and surgical recovery time of a total laparoscopic hysterectomy (Case 2). Case 1 is a 19-year-old, gravida 0, para 0 woman with dysmenorrhea and recurrent pelvic pain who presented for multiple emergency room and outpatient evaluations. Transvaginal ultrasonography was unremarkable except for a 28×30×26mm left lateral uterine mass with peripheral vascular flow that was initially felt to be a leiomyoma or rudimentary uterine horn. MRI imaging, however, demonstrated this mass to be more consistent with an ACUM. This was based on the lack of communication between the lesion and the main uterine cavity exhibited by high T2 signal (compatible with endometrial tissue) surrounding low T2/high T1 signal in the dependent aspects (representing blood products). After counseling regarding treatment options including medical management with hormonal contraception, the patient elected for definitive fertility preserving laparoscopic resection. In contrast, case 2 is a 39-year-old, gravida 3, para 3 woman with a 2 month history or left lower quadrant pain following her last vaginal delivery. Transvaginal ultrasonography showed a 23×18×19mm cystic structure within the left uterine wall, which was confirmed to represent an ACUM on MRI. Although she had no desire for fertility preservation, the patient elected for surgical resection of the mass as opposed to a hysterectomy in order to minimize complications and recovery time.

INTERVENTIONS

Laparoscopic resection of ACUMs in patients desiring uterine preservation.

MEASUREMENTS AND MAIN RESULTS

Laparoscopic resection of the ACUMs was performed utilizing 2 different techniques. In both cases, dilute vasopressin was injected with a modified butterfly or spinal needle along the uterine-ACUM serosal interphase to aid with hemostasis. In patients desiring to preserve fertility (case 1) monopolar energy is utilized to make an incision along the ACUM serosa to help facilitate dissection. ACUM enucleation is then commenced in a circumferential manner along the ACUM and uterine myometrial interphase utilizing bipolar energy. In contrast to leiomyomas where dissection advances along the pseudocapsule, ACUM have poorly delineated borders with disorganized muscular fibers making dissection particularly difficult. A variety of instruments can be utilized to help in the sequential circumferential dissection in addition to a bipolar device including a single-tooth tenaculum, myoma hook, suction device or fine-needle grasper. Ultimately, the ACUM is transected off its uterine-myometrial attachment and hemostasis is obtain before closing the uterine defect in at least 2 layers using a 2-0 barbed V-Loc (Medtronic, Minneapolis, MN). If fertility preservation is no longer desired, the dissection can greatly be expedited by performing a salpingectomy and skeletonizing the ACUM from the leaves of the broad ligament (case 2). A monopolar L-hook can then be used to transect the ACUM from the remaining uterine body. While difficult, these cases can be completed laparoscopically in approximately 2 hours with minimal blood loss.

CONCLUSIONS

ACUMs are hypothesized to represent a previously under recognized Müllerian anomaly linked to gubernaculum dysfunction that occurs in premenopausal women with dysmenorrhea and chronic pelvic pain. Uterine and fertility sparing laparoscopic resection is possible but challenging due to poorly defined planes.

Accessory and cavitated uterine mass with functional endometrium in an adolescent: diagnosis and laparoscopic excision technique

STUDY OBJECTIVE

Accessory and cavitated uterine masses (ACUM) with functional endometrium can be treated successfully with laparoscopic excision. The objectives of this report are to illustrate the surgical technique used for the removal of this uterine wall mass and to discuss the patient's clinical course and outcomes.

DESIGN

Surgical technique and description of 1 case.

SETTING

Department of Obstetrics and Gynecology, University Hospitals Case Medical Center.

PARTICIPANT(S)

A 16-year-old adolescent presented with severe dysmenorrhea and pelvic pain. Ultrasonographic examination and MRI demonstrated a cystic uterine wall mass distinct from the endometrial cavity.

INTERVENTION(S)

Laparoscopic excision of uterine mass.

RESULTS

Pathologic examination of the mass was consistent with an accessory and cavitated uterine mass. A 9-month follow-up after surgical excision of the mass confirmed complete symptom resolution.

CONCLUSIONS

ACUM is a unique and not uncommon pathologic category in the adolescent and young adult population. It is associated with severe and intractable dysmenorrhea and pelvic pain. Laparoscopic excision of these masses is justifiable, safe and feasible.