Imaging modalities in pregnant cancer patients

Abstract

Cancer during pregnancy is increasingly diagnosed due to the trend of delaying pregnancy to a later age and probably also because of increased use of non-invasive prenatal testing for fetal aneuploidy screening with incidental finding of maternal cancer. Pregnant women pose higher challenges in imaging, diagnosis, and staging of cancer. Physiological tissue changes related to pregnancy makes image interpretation more difficult. Moreover, uncertainty about the safety of imaging modalities, fear of (unnecessary) fetal radiation, and lack of standardized imaging protocols may result in underutilization of the necessary imaging tests resulting in suboptimal staging. Due to the absence of radiation exposure, ultrasound and MRI are obvious first-line imaging modalities for detailed locoregional disease assessment. MRI has the added advantage of a more reproducible comprehensive organ or body region assessment, the ability of distant staging through whole-body evaluation, and the combination of anatomical and functional information by diffusion-weighted imaging which obviates the need for a gadolinium-based contrast-agent. Imaging modalities with inherent radiation exposure such as CT and nuclear imaging should only be performed when the maternal benefit outweighs fetal risk. The cumulative radiation exposure should not exceed the fetal radiation threshold of 100 mGy. Imaging should only be performed when necessary for diagnosis and likely to guide or change management. Radiologists play an important role in the multidisciplinary team in order to select the most optimal imaging strategies that balance maternal benefit with fetal risk and that are most likely to guide treatment decisions. Our aim is to provide an overview of possibilities and concerns in current clinical applications and developments in the imaging of patients with cancer during pregnancy.

Pushing the boundaries. Concurrent Hodgkin lymphoma and breast cancer treatment with preservation of pregnancy: A case report

“…In pregnant patients, WB-DWI/MRI is considered a non-irradiating alternative to PET-CT for diagnosing and staging of cancers and lymphoma ( Han et al, 2018 ). Specifically for lymphoma, WB DW-MRI has shown a concordance of up to 99.4% for detecting nodal and extranodal lymphoma and allows a reliable interim response evaluation ( Vandecaveye et al, 2021 , Mayerhoefer et al, 2014 ). In our case, a favorable interim response on WB-DWI/MRI after two cycles of ABVD resulted in the removal of bleomycin from the chemotherapy schedule, reducing the risk of maternal pulmonary toxicity with added benefit of decreasing fetal chemotherapy exposure.…”

Ten-year experience of a national multidisciplinary tumour board for cancer and pregnancy in the Netherlands

“…The CIP-MDT recommended performing a histologic examination of the placentas due to the increased risk of placental metastasis in melanoma patients, especially in the case of metastatic disease [18]. Diagnostic imaging, including fluorine-18-fluorodeoxyglucose positron emission tomography integrated with computed tomography, was considered feasible for three patients when necessary for treatment planning since the radiation dose is far below the threshold for fetal damage [19].…”

How Could Nanomedicine Improve the Safety of Contrast Agents for MRI during Pregnancy?

“…MRI can also be used as an alternative to US and CT for the diagnosis of cancer. Breast cancer is the most frequently diagnosed cancer in pregnant women [18,19]; other gynecological malignancies, such as cervical and ovarian cancer, or increasingly common colorectal cancers, may also prompt the need for MRI investigations [16,18,20]. This imaging system can also be applied in the evaluation of the brain, chest maternal diseases, musculoskeletal disorders, cardiovascular post-operative evaluation, and monitoring of congenital or acquired heart pathologies [21,22].…”