title: 3D-conformal radiotherapy for prevention of carotid recurrent in-stent restenosis. Initial experience.
abstract: OBJECTIVE
  To investigate 3D-conformal external beam radiotherapy for prevention of recurrent instent restenosis after carotid artery angioplasty.
  
  
  METHODS
  Between Oct 2000 and Sep 2001 five patients with recurrent carotid artery in-stent restenosis of more than 50% lumen loss diagnosed with duplex sonography were enrolled. After successful revascularization, radiotherapy treatment planning was performed, which was based on the angioplasty protocol and all images documenting the intervention. A single dose of 5 Gy was prescribed to the 100% isodose. The treatment started on day one after angioplasty. In total, 4 fractions were given within 3 days.
  
  
  RESULTS
  All patients tolerated the treatment well. No acute radiotherapy associated side effects were observed. Two patients developed recurrence within four months after therapy. In both cases, late total occlusion of the stent was noticed. One patient died and one developed a severe stroke. The other three patients remained asymptomatic with evidence of less than 50% restenosis.
  
  
  CONCLUSIONS
  3D-conformal radiotherapy is a feasible treatment option for highly selected patients with carotid artery in-stent restenosis. These preliminary results from a very small group of patients do show some potential for radiotherapy to prevent restenosis. However, due to the risk of late stent thrombosis, radiotherapy for the prevention of recurrent carotid artery in-stent restenosis is not recommended.
authors.affiliation: Department of Radiotherapy and Radiobiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria. boris.pokrajac@meduniwien.ac.at
authors.forename: Boris
authors.initials: B
authors.lastname: Pokrajac
authors.forename: Ramazali
authors.initials: R
authors.lastname: Ahmadi
authors.forename: Rainer
authors.initials: R
authors.lastname: Schmid
authors.forename: Martin
authors.initials: M
authors.lastname: Schillinger
authors.forename: Christian
authors.initials: C
authors.lastname: Kirisits
authors.forename: Erich
authors.initials: E
authors.lastname: Minar
authors.forename: Richard
authors.initials: R
authors.lastname: Pötter
mesh_terms: D000368:Aged; D000800:Angioplasty, Balloon; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000517:prevention & control* / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011856:Radiographic Image Enhancement; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal; D012008:Recurrence; D015607:Stents; D013997:Time Factors; D014057:Tomography, X-Ray Computed