Rate of Pathology Confirmed Adenomyosis in Setting of Endometriosis

INTRODUCTION: In patients with endometriosis presenting with heavy menstrual bleeding or centralized pelvic pain, adenomyosis is frequently suspected. Definitive therapy via hysterectomy may be recommended for treatment and pathologic confirmation. An understanding of the true rate of coincidence of endometriosis and adenomyosis remains unknown. OBJECTIVE: To understand the rates of pathology-confirmed adenomyosis occurring in the setting of endometriosis and identify predictive factors for the diagnosis of adenomyosis. METHODS: Retrospective cross-sectional study of patients undergoing concurrent hysterectomy and excision of endometriosis with pathologic confirmation. Serial pathologic sectioning of the uterus and extensive sampling when no obvious gross lesions identified were performed to evaluate for adenomyosis. P-values less than 5% were considered statistically significant. RESULTS: This study included 95 patients with adenomyosis noted in 53 (55.8%; 95% CI: 45.2%, 66.0%). The average age of participants was 39.7 years (SD=7.3) with an average body mass index of 28.9 kg/m2 (SD=6.5). Most participants were White (82.6%). The primary indications for hysterectomy were pelvic pain (78.9%), menorrhagia (37.9%), and endometriosis (24.2%). There were no statistically significant differences in parity, uterine weight, or endometriosis stage in those with or without adenomyosis. Significant factors included age [adenomyosis: 40.9 years (SD=7.1) vs no adenomyosis: 38.1 years (7.4)] (p=0.026), dyspareunia (52.9% vs 81.0%; p=0.006), and prior dilation and curettage of the uterus (D&C) (24.5% vs 9.5%; p=0.039). There were no statistically significant differences in the history of cesarean section (p=0.493), laparotomy (p=0.165), or laparoscopy (p=0.675) in those with or without adenomyosis. Hormone use at time of surgery and past endometriosis surgery was not predictive of adenomyosis. Forty-seven (53.4%) patients underwent preoperative MRI, 28 (31.8%) ultrasound, and 13 (14.8%) bowel-prepped ultrasound. Adenomyosis confirmatory rates were 40%, 29.4%, and 28.6%, respectively. After adjusting for age, ethnicity, and imaging type, patients with prior D&C were 4.6 times at risk of having adenomyosis (OR: 4.6; 95% CI: 1.19, 23.5). However, patients with dyspareunia were less likely to have adenomyosis (OR: 0.21; 95% CI: 0.06, 0.61). CONCLUSIONS: Among the women with endometriosis, 45.2% did not have coinciding adenomyosis. Future studies should also investigate whether the observed significance between the D&C procedure and pathology-confirmed adenomyosis is due to the procedure itself or the underlying adenomyosis-related symptoms prompting the D&C. This can be executed through retrospective radiologic studies controlled for confounders such as image quality and radiologist variability. Future studies should also continue to identify treatment options that are personalized to the patients’ diagnosis and symptoms. Additionally, there is a need for further investigation into the underlying biological pathways of both endometriosis and adenomyosis.