Lumbosacral plexopathy: A rare long term complication of concomitant chemo-radiation for cervical cancer

Delayed-onset lumbosacral polyradiculitis following proton precision beam therapy for localized prostate cancer: A case report

Introduction

In males, prostate cancer is the second most diagnosed cancer worldwide and the sixth leading cause of cancer death. Radiation therapy is a common treatment modality for prostate cancer but carries a multitude of adverse effects, ranging from radiation cystitis to post-radiation neuropathy. Proton beam therapy has gained attention as a valuable alternative, due to its improved precision with targeted dose delivery and reduced toxicity. However, the risk for radiation-induced complications, such as radiation-induced lumbar radiculopathy, is not fully understood and requires further investigation.

Case presentation

We present a 68-year-old man with delayed-onset lumbosacral polyradiculitis following proton precision beam therapy for localized prostate cancer. The patient underwent proton therapy treatment for the prostate and seminal vesicles with favorable results and tumor remission. However, five months after completing radiation therapy, the patient presented with chronic lower extremity pain, weakness, and bilateral lower extremity paresthesias. MRI showed diffuse hyperintensity of bilateral L5-S3 nerve roots and an intramuscular edema-like signal involving the bilateral obturator externus and internus muscles, likely due to radiation. Additionally, EMG findings suggested the presence of chronic bilateral L5 radiculopathy.

Conclusion

The clinical manifestation of delayed-onset radiation-induced lumbosacral plexopathy is a rare and uncommon complication of external beam radiation therapy that presents as radicular or myelopathic symptoms based on the location and severity of the inflammation. This case highlights the need for continued follow-up post-radiation and emphasizes the need for a comprehensive review of the oncological history of cancer patients.

Radiation-Induced Lumbosacral Plexopathy

Lumbosacral plexopathy (LSP) encompasses a group of disorders affecting post-ganglionic fibers derived from the L1-S4 roots. The differential diagnosis is challenging and includes other neuropathies of medullary, radicular, or peripheral origin. Defining the etiology is equally crucial, as LSP management relies on its cause. A thorough clinical history should address potential neoplastic disease (new-onset, progression, or relapse), diabetes mellitus, lumbar or pelvic trauma, and previous exposure to radiation. This is the case of a 78-year-old male, with a history of prostatic adenocarcinoma, treated with image-guided radiation therapy and hormone therapy five years before, with no evidence of relapse on follow-up. The patient presented with bilateral weakness, numbness, and paresthesia of lower limbs, gradually progressing over a three-month period, and followed by an acute worsening with inability to stand or walk. He also referred to distal mild edema, episodic hematuria, and urinary incontinence. Physical examination revealed paraparesis affecting proximal and distal leg muscles, along with bilateral hypoesthesia, impaired deep tendon reflexes, and proprioception below knee level. Pelvic, dorsal, and lumbosacral MRI excluded neoplastic lesions but identified somatic fracture of L5 without medullary or conus medullaris compromise. These findings did not explain the clinical picture. Further neurophysiologic studies characterized sensory-motor deficits as post-ganglionic, with specific spontaneous discharges of the muscle fibers, known as myokymia. These findings were consistent with radiation-induced LSP and were supported by MRI. Radiation-induced cystitis was also documented in pelvic MRI and urethral cystoscopy. This case highlights the clinical picture and differential diagnosis of radiation-induced LSP. Despite more typical symptoms and course, a neoplastic origin should always be carefully investigated and excluded. Radiation protocol should be carefully accessed, and its complications should not be overlooked, as they might cause severe morbidity.

A case report of lumbosacral plexopathy in a patient with a history of sacral chordoma and radiotherapy: Will the detection of myokymia on the EMG help to solve the case?1

BACKGROUND

When a patient with a prior history of malignancy and radiotherapy develops progressive weakness as a presentation of plexus involvement, the differential diagnosis usually rests between radiation-induced plexopathy and invasion from recurrent tumor. The presence of myokymic discharges is helpful in differentiating radiation-induced from neoplastic plexopathy.

OBJECTIVE

To present a case report of a patient with chordoma, a locally aggressive tumor, who was diagnosed with recurrent tumor accompanied by the occurrence of myokymia in needle electromyographic examination.

METHOD

A 55-year-old male patient with a history of chordoma and radiotherapy presented to our outpatient clinic with complaints of foot drop, and impaired walking for two months. His latest magnetic resonance imaging (MRI) which was performed three months earlier did not show recurrence. Upon electromyographic evaluation, myokymia, the pathognomic electromyography abnormal wave for radiation plexopathy was detected supporting a diagnosis of radiation plexitis rather than recurrent neoplastic invasion. One month later he presented with more severe pain and was re-evaluated by an MRI, on which a mass was detected indicating relapse.

CONCLUSION

With this case report, we would like to emphasize that the behaviour of the tumor should be considered and imaging should be repeated when tumors display aggressive or recurrent behaviour.

Case report: radiation-induced lumbosacral plexopathy - a very late complication of radiotherapy for cervical cancer

BACKGROUND

Lumbosacral plexopathy caused by radiotherapy is a rare but severe consequence of cancer treatment. This condition often leads to varying degrees of sensory and motor impairment. Neurological complications, which are typically permanent, manifest a long period after irradiation.

CASE PRESENTATION

We describe a case of progressive lower extremity weakness and sensory impairment in a woman who had been effectively treated with radiotherapy for cervical cancer with development 36 years after irradiation. The electrophysiological assessment revealed a subacute bilateral axonal lesion of the lumbosacral plexus. None of the clinical manifestations, serology, cerebrospinal fluid or imaging data discovered an explanation other than radiation-induced lumbosacral plexopathy (RILP).

CONCLUSIONS

This case demonstrates that RILP may emerge more than 30 years after the radiotherapy.

Radiotherapy-Specific Chronic Pain Syndromes in the Cancer Population: An Evidence-Based Narrative Review

While radiation therapy is increasingly utilized in the treatment paradigm of many solid cancers, the chronic effects of radiation therapies are poorly characterized. Notably, understanding radiation-specific chronic pain syndromes is paramount given that the diagnosis and management of these conditions can serve to prevent long-standing functional impairments, optimize quality of life, and even allow for continued radiotherapy candidacy. These radiation-specific chronic pain phenomena include dermatitis, mucositis, enteritis, connective tissue fibrosis, lymphedema, and neuropathic pain syndromes. It is necessary to maintain a low threshold of suspicion for appropriately diagnosing these conditions as there exists a variance in when these symptoms arise after radiation. However, we present key epidemiological data delineating vulnerable cancer populations for each pain syndrome along with the available evidence for the management for each specific condition.