Lumbosacral plexopathy after short-course neoadjuvant radiotherapy for rectal cancer: A case report.

Radiation-induced lumbosacral plexopathy (RILSP) is a rare complication associated with pelvic radiotherapy. Literature is scant about the incidence of RILSP after a neoadjuvant short-course radiotherapy (RT) in rectal cancer. In this report, we detail the symptoms, signs, and management of RILSP. Volumetric modulated arc therapy was used for delivering preoperative short-course RT in our rectal cancer patient. Six months after the completion of RT, the patient presented with symptoms of lower extremity motor and sensory impairment. An electrodiagnostic study revealed a pattern of bilateral sciatic nerve injury or a lower lumbosacral plexus abnormality. Magnetic resonance imaging showed radiation-related edema in the region of the lumbosacral plexus. Further blood and serum investigations ruled out other inflammatory and infectious differential diagnoses, thus a diagnosis of RILSP was made. He was initiated on analgesics and was also referred to physiotherapy and rehabilitation. After 2 months, his symptoms stabilized.