Adenomyosis and Its Possible Malignancy: A Review of the Literature

Cancer arising from adenomyosis is very rare, with transformation occurring in only 1% of cases and in older individuals. Adenomyosis, endometriosis and cancers may share a common pathogenic mechanism that includes hormonal factors, genetic predisposition, growth factors, inflammation, immune system dysregulation, environmental factors and oxidative stress. Endometriosis and adenomyosis both exhibit malignant behaviour. The most common risk factor for malignant transformation is prolonged exposure to oestrogens. The golden standard for diagnosis is histopathology. Colman and Rosenthal emphasised the most important characteristics in adenomyosis-associated cancer. Kumar and Anderson emphasised the importance of demonstrating a transition between benign and malignant endometrial glands in cancer arising from adenomyosis. As it is very rare, it is difficult to standardize treatment. In this manuscript, we try to emphasize some aspects regarding the management strategy, as well as how heterogenous the studies from the literature are in terms of prognosis in both cancers that develop from adenomyosis or those that are only associated with adenomyosis. The pathogenic mechanisms of transformation remain unclear. As these types of cancer are so rare, there is no standardised treatment. A novel target in the diagnosis and treatment of gynaecological malignancies associated with adenomyosis is also being studied for the development of new therapeutic concepts.