ESTRO 2024 - Abstract Book

S1833

Clinical - Mixed sites, palliation

ESTRO 2024

[1] Zheng, D., Q. Zhang, et al. (2016). "Effect of the normalized prescription isodose line on the magnitude of Monte Carlo vs. pencil beam target dose differences for lung stereotactic body radiotherapy." Journal of Applied Clinical Medical Physics 17(4): 48-58. [2] Zhuang, T., T. Djemil, et al. (2013). "Dose calculation differences between Monte Carlo and pencil beam depend on the tumor locations and volumes for lung stereotactic body radiation therapy." Journal of Applied Clinical Medical Physics 14(2): 38-51.

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Digital Poster

Postoperative Radiotherapy in Treatment of Dupuytren's Contracture

Erin McCammack, Kathryn Dusenbery

University of Minnesota, Radiation Oncology, Minneapolis, USA

Purpose/Objective:

In early stage Dupuytren’s contracture (DC), radiotherapy (RT) has been shown to prevent disease progression. Once contracture has occurred, RT is ineffective. Contracture release via surgery or collagenase injection can reverse contracture, but recurrence is common. We hypothesized that the risk of recurrence in a joint could be reduced by immediate postoperative RT (PORT) as in other benign hypertrophic reactions like keloid and heterotopic bone.

Material/Methods:

9 patients and 25 joints with contracture (20 or more degrees) were treated with surgery and PORT. The total dose was 30Gy delivered in a split course of 15Gy in 5 fractions with a 6-8 week break followed by 15Gy in 5 fractions. All joints were treated with electron beams targeting the surgical bed with a 1cm margin. Bolus was applied to ensure coverage at depth. During RT, patients were seen once weekly. After completion of treatment, patients were followed annually. Recurrent contracture severity was documented in progress notes with photographs. A retrospective chart review was conducted including patients with a diagnosis of palmar fibromatosis or Dupuytren’s Disease who underwent PORT within three months of a contracture surgery. Patients with prior radiation to the hand were excluded.

Results:

20 joints had a median of 2 (range 1 to 5) prior surgeries, while 5 joints underwent a first surgery. The type of pre-RT surgery varied, with 3 joints being treated with collagenase injection (C), 2 joints with needle aponeurotomy (N) and 20 joints with fasciectomy (F). PORT began at a median of 12 days (range 1 to 68 days) after surgery. Grade 1 acute radiation dermatitis was reported in 3 joints. No other acute or late toxicities were reported. Recurrent contracture occurred in 13/25 joints (52%) with the majority of recurrences 8/13 (62%) occurring within one year of surgery. In