Dose–Volume Modeling of Brachial Plexus-Associated Neuropathy After Radiation Therapy for Head-and-Neck Cancer: Findings From a Prospective Screening Protocol

Journal Article · Sat Mar 15 04:00:00 EDT 2014 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2013.11.244· OSTI ID:22416483

Wang, Pin-Chieh ^[1]; Daly, Megan E.; Cui, Jing; Hall, William H. ^[2]; Vijayakumar, Srinivasan ^[3]; Phillips, Theodore L. ^[2]; Farwell, D. Gregory ^[4]; Purdy, James A. ^[2]

---

1. Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California (United States)
2. Department of Radiation Oncology, University of California, Davis, Comprehensive Cancer Center, Sacramento, California (United States)
3. Department of Radiation Oncology, University of Mississippi School of Medicine, Jackson, Mississippi (United States)
4. Department of Otolaryngology–Head and Neck Surgery, University of California, Davis, Comprehensive Cancer Center, Sacramento, California (United States)

Purpose: Data from a prospective screening protocol administered for patients previously irradiated for head-and-neck cancer was analyzed to identify dosimetric predictors of brachial plexus-associated neuropathy. Methods and Materials: Three hundred fifty-two patients who had previously completed radiation therapy for squamous cell carcinoma of the head and neck were prospectively screened from August 2007 to April 2013 using a standardized self-administered instrument for symptoms of neuropathy thought to be related to brachial plexus injury. All patients were disease-free at the time of screening. The median time from radiation therapy was 40 months (range, 6-111 months). A total of 177 patients (50%) underwent neck dissection. Two hundred twenty-one patients (63%) received concurrent chemotherapy. Results: Fifty-one patients (14%) reported brachial plexus-related neuropathic symptoms with the most common being ipsilateral pain (50%), numbness/tingling (40%), and motor weakness and/or muscle atrophy (25%). The 3- and 5-year estimates of freedom from brachial plexus-associated neuropathy were 86% and 81%, respectively. Clinical/pathological N3 disease (P<.001) and maximum radiation dose to the ipsilateral brachial plexus (P=.01) were significantly associated with neuropathic symptoms. Cox regression analysis revealed significant dose–volume effects for brachial plexus-associated neuropathy. The volume of the ipsilateral brachial plexus receiving >70 Gy (V70) predicted for symptoms, with the incidence increasing with V70 >10% (P<.001). A correlation was also observed for the volume receiving >74 Gy (V74) among patients treated without neck dissection, with a cutoff of 4% predictive of symptoms (P=.038). Conclusions: Dose–volume guidelines were developed for radiation planning that may limit brachial plexus-related neuropathies.

• OSTI ID: 22416483
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 4 Vol. 88; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ATROPHY
CARCINOMAS
CHEMOTHERAPY
HEAD
INJURIES
MUSCLES
NECK
PAIN
PATIENTS
PLANNING
RADIATION DOSES
RADIOTHERAPY
RECOMMENDATIONS
REGRESSION ANALYSIS