[2] Adenomyomas containing endometrial glands are also found outside of the uterus, most commonly on the uterine adnexa but can also develop at distant sites outside of the pelvis.

Adenomyosis most commonly presents with numerous small collections of endometrial glands and stroma spread diffusely throughout the myometrium, intermixed with the myometrial smooth muscle.

The majority of cases of extrauterine adenomyomas described in the literature have been located in the pelvis, growing on the ovaries, uterine ligaments, and space surrounding the rectum.

[4][5][6] The excessive proliferation of epithelial cells causes the mucosa to invaginate into the muscular layer lining the gallbladder wall, resulting in characteristic diverticula known as Rokitansky-Aschoff sinuses.

[5][6] The clinical features of uterine adenomyosis vary widely and may include dysmenorrhea, pelvic pain, menorrhagia, and/or infertility, with about one in three affected women remaining asymptomatic.

[2] The most frequent complaint in cases of extrauterine adenomyomas is pain in the pelvis or abdomen, with a small proportion of women also presenting with abnormal bleeding and/or infertility.

Though adenomyosis has demonstrated sensitivity to estrogen, further investigation is needed to explore the relationship between hormone therapy and extrauterine adenomyomas.

As errors in Müllerian duct fusion also impact the development of the kidneys, urinary tract, and genitals, this theory would explain the multiple cases of extrauterine adenomyomas with co-existing congenital abnormalities of these anatomic structures.

In this theory, areas of endometrial tissue that have developed outside the uterus (endometriosis) undergo cellular changes that provide the muscular component of the adenomyoma.

[3] The appearance of these rare tumors on diagnostic imaging has not been extensively described, and in each case documented in the literature, the diagnosis was ultimately made after surgical removal using histologic analysis.

[4][5][6] Other key features that may be seen include wall thickening and ring-down artifacts known as "comet tails" (produced by reverberations of sound between the sinuses).

[5][6] In some cases, gallbladder wall thickening may be seen on ultrasound but is poorly defined and lacking specificity, particularly if the characteristic Rokitansky-Aschoff sinuses are not visualized.

Especially effective is the T2-weighted MRI at visualizing the pathognomonic Rokitansky-Aschoff sinuses, which appear as round-shaped hyperintense cystic spaces that align in a curvilinear fashion along the gallbladder wall in a pattern described as the ”pearl necklace sign”.

[4][5][6] Multiple medical and surgical approaches have been explored to treat uterine adenomyomas, and a patient’s symptoms and reproductive preferences must be considered carefully when choosing the most appropriate therapy.

[2] Adenomyomectomy, a conservative surgery that removes the localized tumor but leaves the surrounding healthy uterus intact, is a potential uterine-sparing option for women with a uterine adenomyoma who wish to preserve their fertility, as some of the previously listed interventions decrease or eliminate the probability of successful future childbearing.

The surgical technique applied for tumor excision highly depends on the mass’s location, with gynecologic surgeries such as hysterectomy and salpingo-oophorectomy a common choice for pelvic adenomyomas.

[4][5][6] There is a lack of consensus as to the optimal management of asymptomatic patients, largely due to uncertainties about the possible role of adenomyomatosis in the development of gallbladder cancer.

[2][7] There are a small number of studies that have demonstrated improved outcomes in pregnancy when combining conservative surgery with GnRH agonist therapy compared to either method alone.

[2][7] In the case of juvenile cystic adenomyoma, laparoscopic enucleation results in a statistically and clinically significant reduction in dysmenorrhea, ease in any chronic pelvic pain, and low risk of recurrence.

[8] Long-term outcomes after treatment are sparsely represented in prior studies, though a small number of cases reported recurrence of adenomyomas after surgery.