Abstract
Radiation-induced lumbosacral plexopathy (RILSP) is an uncommon complication of pelvic radiotherapy that can result in different degrees of sensory and motor deficits. An age 59 female with cervical cancer, who had received combined chemotherapy and radiation therapy two years before, presented with bilaterally symmetric lower-extremity weakness and tingling sensation. The magnetic resonance imaging showed diffuse T2 bright signal intensity and mild enhancement along the bilateral lumbosacral plexus with no space-occupying masses. RILSP was diagnosed after the exclusion of malignant and inflammatory plexopathies.
REFERENCES
1.Harper CM Jr., Thomas JE., Cascino TL., Litchy WJ. Distinction between neoplastic and radiation-induced brachial plexopathy, with emphasis on the role of EMG. Neurology. 1989. 39:502–506.
2.Taylor BV., Kimmel DW., Krecke KN., Cascino TL. Magnetic resonance imaging in cancer-related lumbosacral plexopathy. Mayo Clin Proc. 1997. 72:823–829.
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
3.Emami B., Lyman J., Brown A, et al. Tolerance of normal tissue to therapeutic irradiation. Int J Radiat Oncol Biol Phys. 1991. 21:109–122.
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
4.Tunio M., Al Asiri M., Bayoumi Y, et al. Lumbosacral plexus delineation, dose distribution, and its correlation with radiation-induced lumbosacral plexopathy in cervical cancer patients. Onco Targets Ther. 2015. 8:21–27.
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
5.Cavanagh JB. Effects of x-irradiation on the proliferation of cells in peripheral nerve during Wallerian degeneration in the rat. Br J Radiol. 1968. 41:275–281.
6.Delanian S., Lefaix JL. The radiation-induced fibroatrophic process: therapeutic perspective via the antioxidant pathway. Radiother Oncol. 2004. 73:119–131.
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
7.Denham JW., Hauer-Jensen M. The radiotherapeutic injury–a complex ‘wound’. Radiother Oncol. 2002. 63:129–145.
Fig. 1.
Contrast-enhanced hip MRI two years after the completion of CCRT. Coronal MRI at the first sacral foramen level reveals bilateral, symmetric, and diffuse T2 hyperintensity of LSP on coronal FS T2WI (a, arrows). The consecutive coronal FS T2WIs in the posterior direction demonstrated extensive involvement of LSP (b, c, arrows). Also, diffuse mild enhancement of the impacted LSP at the first sacral foramen level is depicted on T1WI (d, arrows) and contrast-enhanced T1WI (e, arrows). Note the asymmetric T2 signal change (pronounced on the right side) of the bilateral piriformis muscle (f, arrows). FS = fat suppressed; LSP = lumbosacral plexus
![imri-24-46f1.tif](/upload/SynapseXML/1040imri/thumb/imri-24-46f1.gif)
Fig. 2.
The MR feature of the LSP before CCRT. The pre-CCRT pelvic protocol MRI (a, axial T2WI; b, oblique coronal T2WI perpendicular to the cervix) reveal normal bilateral LSP at both of the sciatic foramen (arrows). Newly defined diffuse thickening of the bilateral LSP after CCRT completion can be heightened by comparing the images acquired before and after the CCRT. LSP = lumbosacral plexus
![imri-24-46f2.tif](/upload/SynapseXML/1040imri/thumb/imri-24-46f2.gif)