Diffusion-weighted imaging and dynamic contrast-enhanced MRI in assessing response and recurrent disease in gynaecological malignancies

Abstract

Magnetic resonance imaging (MRI) has an established role in imaging pelvic gynaecological malignancies. It is routinely used in staging endometrial and cervical cancer, characterizing adnexal masses, selecting optimal treatment, monitoring treatment and detecting recurrent disease. MRI has also been shown to have an excellent performance and an evolving role in surveillance of patients after chemoradiotherapy in cervical cancer, post-trachelectomy, detecting early recurrence and planning exenterative surgery in isolated central recurrences in both cervical and endometrial cancer and in young patients on surveillance for medically managed endometrial cancer. However, conventional MRI still has limitations when the morphological appearance of early recurrent or residual disease overlaps with normal pelvic anatomy or treatment effects in the pelvis. In particular, after chemoradiotherapy for cervical cancer, distinguishing between radiotherapy changes and residual or early recurrent disease within the cervix or the vaginal vault can be challenging on conventional MRI alone. Therefore, there is an emerging need for functional imaging to overcome these limitations. The purpose of this paper is to discuss the emerging functional MRI techniques and their applications in predicting treatment response, detecting residual disease and early recurrent disease to optimize the treatment options available using diffusion-weighted imaging and dynamic contrast enhancement particularly in cervical and endometrial cancer.

Added Value of Perfusion in Gynaecological Imaging

“…Recently, the advancement of contrast enhanced Magnetic Resonance Imaging (MRI) has lead to offering an in vivo functional examination, where information on the structure and function of the tumor microvasculature can be provided [7]. Many studies now support the use of functional MRI in assessment of tumor response to therapy with promising results, particularly in cervical cancer [5]. DCE-MRI has the ability to noninvasively assess tumor perfusion and capillary permeability and thus assessing the anti angiogenic response of tumor tissue after therapy, which allows evaluation of treatment response earlier than using the conventional methods of assessing tumor size [8].…”

“…Also, owing to the similar morphological appearance, conventional imaging has a limited value in assessing tumor's response to therapy and differentiating between residual /recurrent disease and post-treatment fibrosis [5,6]. Recently, the advancement of contrast enhanced Magnetic Resonance Imaging (MRI) has lead to offering an in vivo functional examination, where information on the structure and function of the tumor microvasculature can be provided [7].…”

“…Recent advances in MRI such as increased field strength, development of parallel imaging [3,4], and the use of novel methods of rapid data acquisition have markedly improved image quality in body MRI applications [4]. MRI plays a pivotal role, owing to its good soft tissue resolution that allows accurate topographic assessment of the tumor (size, location, extension and nodal involvement) [5].…”

“…Aggressive tumors mostly show rapid and intense enhancement and washout, due to high vascularity and strong expression of VEGF [8]. The use of post therapy DCE-MRI in cervical and endometrial cancer may be able to predict which patients are at risk of early recurrence and therefore super select patients suitable for more aggressive surgery [5]. In general, DCE perfusion MRI is very safe.…”

“…The early predictability of tumor response after therapy provides a golden opportunity to quickly change failed treatment regimens, limiting the related side effects and high costs and instituting these regimens with more successful ones [5,9]. Dynamic contrast enhanced MRI (DCE-MRI) is performed by acquisition of multiple sequential images before, during and after the passage of contrast material through a specific area of interest [8].…”