Deep endometriosis demystified: Natural progression, hormonal treatment, and malignant transformation

We present a review of the natural progression, response to hormonal therapy, and risk of malignancy associated with deep endometriosis (DE) to guide evidence-based discussion of conservative treatment.

Advanced imaging protocols have enhanced nonsurgical detection of DE, allowing noninvasive diagnosis, treatment, and surveillance. While some DE is progressive, 50% of disease appears stable over time, and progression is reduced by half with hormonal treatments (21 versus 12%). Hormonal treatment can reduce the size of DE lesions by 1 cm³, with reductions occurring after 6 months and remaining stable up to 3 years. Most hormonal therapies improve symptoms and quality of life, regardless of changes in DE size, with combined contraceptives and progestins being the most studied. DE may present a higher risk of ovarian and extraovarian cancer than previously hypothesized, though further research is needed to confirm findings. Limitations of DE research include differing imaging strategies, definitions of disease and progression, short follow-up, focus on rectosigmoid DE only, and lack of randomized trials.

DE is a subtype of endometriosis that is increasingly diagnosed and treated with noninvasive strategies. Hormonal treatments improve symptoms and reduce progression of DE. Further research on optimal conservative management and risk of malignancy is warranted.