Increased Risk for Non-Healing Wounds with Neutron Bean Radiotherapy (NBT)

• NBT is for large, hypoxic, slow growing tumors, often non-resectable with high morbidity.
• Compared with x-ray radiation therapy (XRT), the high-linear energy transfer (LET) of NBT is associated with greater cell killing.
• There is a markedly increased complication rate of osteoradionecrosis (ORN) after definitive surgery and NBT¹. 
• NBT has an increased risk of skin breakdown, and non-healing after injury, due to decreased capillary bed circulation. "Cancer patients who undergo radiotherapy remain at life-long risk of radiation-induced injury to normal tissues.²”

 Case Study: TM, a 28 year-old woman with Adenoid Cystic Carcinoma (ACC) of the head and neck was diagnosed at age 13 and treated with radical surgery and NBT.

ACC is a rare, slow growing, cancer with a high rate of treatment failure (62%). ³ TM developed ORN of the mandible and neck causing loss of all teeth, softening of the mandible and radiation skin changes, resulting in severe disfigurement of her neck and facial features. She received 35 Hyperbaric Oxygen therapy (HBO) treatments before mandible reconstructive surgery.

Two weeks post-surgery, the fibular free flap mandible reconstruction was healing; unfortunately the peri-incision tissue in her neck had become necrotic with a large area of slough.

 Treatment: The patient received 35 additional HBO treatments as an adjunct to wound care. “HBO has been shown to induce neovascularization in this hypoxic milieu and to reduce fibrosis in irradiated tissues”. ⁴

 The necrotic tissue was autolytically debrided. Sharp debridement was not possible due to the proximity of the carotid artery. Daily care, using a polyacylate dressing progressed to complete healing over the next 10 weeks.

 Conclusions/recommendations: NBT has an increased risk for skin breakdown with slower healing rates. Patients with non-healing wounds in radiated tissue need to be evaluated and treated using aggressive HBO therapy and advanced wound care.