Adenomyoma is a benign tumor that consists of glandular and muscular tissue, often found in the uterus. It is a type of adenomatous tumor that may arise from the endometrial tissue and can lead to symptoms such as pelvic pain or heavy menstrual bleeding. While generally not harmful, it can sometimes be mistaken for other conditions, so proper diagnosis through imaging or biopsy is essential. Treatment may involve monitoring or surgical removal if symptoms are significant.