IMRT for sinonasal tumors minimizes severe late ocular toxicity and preserves disease control and survival

Int J Radiat Oncol Biol Phys. 2012 May 1;83(1):252-9. doi: 10.1016/j.ijrobp.2011.06.1977. Epub 2011 Oct 24.

Abstract

Purpose: To report late ocular (primary endpoint) and other toxicity, disease control, and survival (secondary endpoints) after intensity-modulated radiotherapy (IMRT) for sinonasal tumors.

Methods and materials: Between 1998 and 2009, 130 patients with nonmetastatic sinonasal tumors were treated with IMRT at Ghent University Hospital. Prescription doses were 70 Gy (n = 117) and 60-66 Gy (n = 13) at 2 Gy per fraction over 6-7 weeks. Most patients had adenocarcinoma (n = 82) and squamous cell carcinoma (n = 23). One hundred and one (101) patients were treated postoperatively. Of 17 patients with recurrent tumors, 9 were reirradiated. T-stages were T1-2 (n = 39), T3 (n = 21), T4a (n = 38), and T4b (n = 22). Esthesioneuroblastoma was staged as Kadish A, B, and C in 1, 3, and 6 cases, respectively.

Results: Median follow-up was 52, range 15-121 months. There was no radiation-induced blindness in 86 patients available for late toxicity assessment (≥6 month follow-up). We observed late Grade 3 tearing in 10 patients, which reduced to Grade 1-2 in 5 patients and Grade 3 visual impairment because of radiation-induced ipsilateral retinopathy and neovascular glaucoma in 1 patient. There was no severe dry eye syndrome. The worst grade of late ocular toxicity was Grade 3 (n = 11), Grade 2 (n = 31), Grade 1 (n = 33), and Grade 0 (n = 11). Brain necrosis and osteoradionecrosis occurred in 6 and 1 patients, respectively. Actuarial 5-year local control and overall survival were 59% and 52%, respectively. On multivariate analysis local control was negatively affected by cribriform plate and brain invasion (p = 0.044 and 0.029, respectively) and absence of surgery (p = 0.009); overall survival was negatively affected by cribriform plate and orbit invasion (p = 0.04 and <0.001, respectively) and absence of surgery (p = 0.001).

Conclusions: IMRT for sinonasal tumors allowed delivering high doses to targets at minimized ocular toxicity, while maintaining disease control and survival. Avoidance of severe dry eye syndrome and radiation-induced blindness suggests IMRT as a standard treatment for sinonasal tumors.

MeSH terms

  • Adenocarcinoma / radiotherapy
  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Adenoid Cystic / radiotherapy
  • Carcinoma, Squamous Cell / mortality
  • Carcinoma, Squamous Cell / radiotherapy
  • Esthesioneuroblastoma, Olfactory / radiotherapy
  • Eye / radiation effects*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Organs at Risk / radiation effects*
  • Paranasal Sinus Neoplasms / mortality
  • Paranasal Sinus Neoplasms / radiotherapy*
  • Radiation Injuries / pathology*
  • Radiotherapy Dosage
  • Radiotherapy, Intensity-Modulated / adverse effects
  • Radiotherapy, Intensity-Modulated / methods*
  • Vision Disorders / etiology
  • Young Adult