Brachial plexus dose tolerance in head and neck cancer patients treated with sequential intensity modulated radiation therapy.
OBJECTIVE
We aimed to study the radiation induced brachial plexopathy in patients with head and neck squamous cell carcinoma (HNSCC) treated with Sequential Intensity Modulated Radiation Therapy (S-IMRT).


METHODS
This IRB approved study included 68 patients with HNSCC treated consecutively. Detailed dose volume histogram data was generated for ipsilateral and contralateral brachial plexus (BP) volumes receiving a specified dose (Vds) i.e. V50-V75 and dose in Gray covering specified percent of BP volume (Dvs) i.e. D5-D30 and maximum point doses (Dmax). To assess BP injury all patients' charts were reviewed in detail for sign and symptoms of BP damage. Post-hoc comparisons were done using Tukey-Kramer method to account for multiple significance testing.


RESULTS
The mean and maximum doses to BP were significantly different (p < .05) based on tumor site, nodal status and tumor stage. The mean volume to the ipsilateral BP for V50, V60, V70, and V75 were 7.01 cc, 4.37 cc, 1.47 cc and 0.24 cc, respectively. The mean dose delivered to ≤5% of ipsilateral BP was 68.70 Gy (median 69.5Gy). None of the patients had acute or late brachial plexopathy or any other significant neurological complications, with a minimum follow up of two years (mean 54 months).


CONCLUSIONS
In this study cohort, at a minimum of two-years follow up, the mean dose of 68.7Gy, a median dose to 69.5Gy to ≤5% of ipsilateral BP, and a median Dmax of 72.96Gy did not result in BP injury when patients were treated with S-IMRT technique. However, longer follow up is needed.
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. tth262@gmail.com.
Tarita O
TO
Thomas
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. tamermr@u.northwestern.edu.|Northwestern Medicine Developmental Therapeutics Institute (NMDTI), Chicago, IL, USA. tamermr@u.northwestern.edu.|Department of Clinical Oncology and Nuclear Medicine, Faculty of Medicine, Alexandria University, Alexandria, Egypt. tamermr@u.northwestern.edu.
Tamer
T
Refaat
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. mehee.choi@gmail.com.
Mehee
M
Choi
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. ian.bacchus@northwestern.edu.
Ian
I
Bacchus
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. sean.sachdev@gmail.com.
Sean
S
Sachdev
Department of Preventive Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, IL, USA. rademaker@northwestern.edu.
Alfred W
AW
Rademaker
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. VSathias@nmh.org.
Vythialingam
V
Sathiaseelan
Department of Radiology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, IL, USA. akaragianis@nmff.org.
Achilles
A
Karagianis
Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, 251 East Huron, LC-178, Chicago, IL, 60611, USA. bmittal@nmh.org.
Bharat B
BB
Mittal
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001917:Brachial Plexus / Q000528:radiation effects*; D020516:Brachial Plexus Neuropathies / Q000209:etiology*; D059248:Chemoradiotherapy / Q000009:adverse effects; D003131:Combined Modality Therapy; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000532:radiotherapy* / Q000601:surgery / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D058958:Organs at Risk; D011183:Postoperative Complications / Q000209:etiology*; D011832:Radiation Injuries / Q000209:etiology*; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods