'Fish in a Net' and 'Swiss cheese' pattern 2 cases of unusual adenomyosis with different β-HCG level.

Myometrial hypertrophy and hyperplasia, which usually on magnetic resonance imaging (MRI) typically reveal an enlarged uterus with ill-defined areas of low signal intensity and a diminished junctional zone, along with small foci of hyperintensity due to ectopic endometrium, are found in uterine adenomyosis. Those are caused by the presence of ectopic endometrial glands and stroma within the uterine myometrium. However, our case reports highlight the importance of recognizing atypical presentations, such as extensive mass-like hyperintense signals resembling a "Fish in a Net" and Swiss cheese pattern on T2-weighted imaging. Recognizing this pattern could aid in preventing misdiagnosis and guiding appropriate management strategies. Furthermore, there is a possibility that the same diagnosis (adenomyosis) could present a different β-human choriogonadotropin hormone (β-HCG) serum level.