Purpose or Case Report: Background: Li-Fraumeni Syndrome (LFS) is an autosomal dominant disorder that predisposes individuals to cancer, associated with mutations in the P53 gene. The most common tumors associated with LFS include breast cancer, osteosarcomas and other sarcomas. Less frequent but also seen are brain tumors, adrenocortical carcinomas and leukemia. However, tumors can manifest almost anywhere in the body.
Given the increased cancer risk, close surveillance is imperative for early cancer detection; guidelines recommend annual Whole Body MRI (WB-MRI) surveillance, along with a series of other imaging and laboratory studies. WB-MRI protocols vary across centers. Although the short tau inversion recovery (STIR)/T2-weighted sequence is accurate for early cancer detection, the combination of STIR/T2 and diffusion-weighted (DW) sequences further increases the diagnostic accuracy of MRI, but at the cost of increased scan time.

Teaching Points: In this educational poster, we will show pediatric surveillance MRI scans in patients with LFS where the utilization of DW-MRI was essential for the diagnosis of cancer or associated conditions, not identified by STIR/T2-weighted MRI solely, along with WB-MRI protocols used in different centers with corresponding total scan time.
Our objective is to demonstrate the added value of using DWI in lesion detection justifying the extended scan duration for surveillance of patients with cancer predisposition disorders. Although it may be uncommon to find lesions exclusively on DWI, the relevance of early cancer diagnosis justifies the time and resources invested in performing this sequence.
Table of contents/Outline:
1. WB-MRI protocols for cancer surveillance in pediatric patients with cancer predisposition disorders.
2. Presentation of cases of:
- Discordant results between DWI and STIR/T2 MRI sequences, false-negative results on STIR/T2 solely.
- Concordant results between DWI and STIR/T2 MRI sequences, true-positive results.
3. Examples of artifacts in DW-MRI that may preclude an accurate diagnosis and approaches to avoid or to minimize them.
Methods & Materials:
Results:
Conclusions: