Fifty-seventh annual meeting of the American association of physicists in medicine
SU-E-T-214: Comparison of Treatment Techniques for Dupuytren's Contracture and Risk Assessment of Normal Tissue Complications
Duputren's contracture (DC) is a benign disease characterized by abnormal thickening of the fascial surfaces of the hands or feet causing curling of the surface, functional impairment, weakness, and pain. The purpose of the investigation is to describe the radiation treatment approaches, compare these techniques, and discuss the potential side effects and complications of these techniques.
Early stage DC has been treated with 120 kVp X rays but also with high-energy electrons or photons. High-energy electrons have been the radiation of choice but severe contracture of the hand makes it difficult to produce a plan with acceptable dose uniformity. High-energy photons can overcome this difficulty either by directing a beam onto the palmer or back of the surface of the hand, including bolus to maximize the surface dose. We calculated the dose to the bone for the 120 kVp treatment using published %DD data and mass energy absorption coefficients for bone and muscle.
The dose to underlying bone from megavoltage photons and electrons is essentially the same, but dose to the bone for using 120 kVp can be 4–5 times greater due to the photoelectric effect. For the 30 Gy dose deliver using this technique, the dose to the bone could be 84–105 Gy after taking the penetration of the beam into account. After radiotherapy, there is often decreased osteoblastic activity and vascular fibrosis that leads to osteitis, atrophy, and decreased metabolic bone activity. Incidence of fractures occurs routinely above 60 Gy with higher doses potentially leading to higher incidences of bone complications.
Radiation therapy for DC using low-energy X rays can deliver a prohibitively high dose to the underlying bone potentially leading to severe bone complications.