One research team prospectively compared TVU to MRI in diagnosing adenomyosis preoperatively. MRI was significantly superior (P< 0.02) Another investigator reported MRI sensitivities ranging from 70% to 82%, specificities 84% to 92%, with the positive predictive value of 58% to 83% and a negative predictive value of 86% to 95%. The approach has also been validated in a study to differentiate adenomyosis from fibroids. The typical appearance on a T2 weighted MRI is a widened band of low intensity in the junctional zone (JZ) of the uterus. A width of greater than 5 to 20 mm is considered significant, but this is also debated. Advantages of MRI include that it is not operator dependent, the images are reproducible, and it is not associated with ionizing radiation; disadvantages are the high cost, limited availability, the lack of consensus of how wide the JZ should be, and low sensitivity.

The literature has also suggested that adenomyosis, often referred to as endometriosis interna, is associated with, if not a variant of, endometriosis, and some have suggested that the two entities usually occur concomitantly. The evidence, however, doesn’t support this notion. Prior controlled studies reported prevalence of endometriosis between 5% to 10% in specimens with adenomyosis and 7% to 8% without adenomyosis. These differences were not statistically significant. The common feature in both diseases is the presence of ectopic endometrial glands and stroma, but this similarity does not necessarily indicate a common cause. These findings suggest that adenomyosis is not more common in the presence of endometriosis and that they are most likely clinically different diseases.

ADENOMYOSIS IS OFTEN found in hysterectomy specimens of women with concurrent fibroids. The reported incidence of concurrent fibroids has ranged from 19% to 57%. Many authors have concluded that this high prevalence reflects an association between adenomyosis and fibroids. However, the majority of these studies did not examine the incidence of fibroids in control specimens, that is, in women without adenomyosis. Two previous authors, Vercellini et al. and Shaikh et al., concluded that fibroids are equally common in specimens with and without adenomyosis.

What symptoms should you expect?

Eighty percent of adenomyosis cases are reported in women between 40 and 50 years old. There is no consistent constellation of symptoms that clearly identify adenomyosis.

In fact, most women are asymptomatic. Classically it has been described to present as a triad: uterine enlargement, pelvic pain, and heavy, abnormal menstrual bleeding. As you might expect, the severity of symptoms correlates with the extent of disease present. When present, these symptoms lead to a presumptive preoperative diagnosis and are often used as an indication for hysterectomy. But keep in mind that 80% of patients with adenomyosis also have another pathologic process present in the uterus that often obscures the diagnosis of adenomyosis.

None of these symptoms, or the triad alone, is pathognomonic for adenomyosis, and attributing the symptoms solely to adenomyosis, and not the other pathologies, may be a mistake. Many symptoms may be due to other concurrent conditions such as fibroids, or dysfunctional uterine bleeding.