Improvement in Strength and Function after Radiation-Induced Neuritis and Myositis: A Case Report

Case Diagnosis: A 63 year old male with a history of metastatic prostate cancer and radiation therapy who had progressive weakness felt to be due to radiation neuritis and radiation myositis demonstrated clinical improvements in strength and function after intensive outpatient physical and occupational therapy.

Case Description or Program Description: A patient with metastatic prostate cancer who had undergone radiation treatment to his pelvis developed rapidly progressive bilateral lower extremity weakness approximately 3 months after undergoing radiation. He underwent an extensive workup, with repeated hospitalizations and multiple specialists from several different institutions were consulted. Ultimately his weakness was felt to be due to a combination of radiation myositis and radiation neuritis, which is usually an irreversible condition.

Setting: Outpatient

Assessment/Results: The patient was following consistently in an outpatient PM&R clinic, and was recommended to begin an intensive outpatient therapy program with three hours of physical and occupational therapy per day for five days per week. He participated in this program for 10 weeks and demonstrated significant functional improvement. He then transitioned to routine outpatient physical therapy, and had continued improvement on serial physical exams as well as functional improvement more than a year after completing the intensive therapy program.

Discussion (relevance): Radiation-induced neuritis is felt to be an irreversible condition, and radiation myositis is only partially reversible. This is an example of a case where a patient demonstrated significant functional recovery over the span of months to years after receiving radiation.

Conclusions: When a patient develops new-onset weakness after undergoing radiation treatment, it is important to pursue an appropriate workup to ensure the correct diagnosis. This case provides evidence that patients with radiation-induced neuritis and myositis may be able achieve significant functional improvement if offered consistent, high-quality, multidisciplinary care involving physical and occupational therapy, physiatry, orthotics, and any other appropriate interventions.