(P092) Definitive Chemoradiotherapy or Radiotherapy for Unresectable, Very Locally Advanced, or Medically Inoperable Paranasal Sinus and Nasal Cavity Cancer

April 30, 2015

Definitive CRT or RT is feasible for unresectable, very locally advanced, or medically inoperable PNS/NC cancer with minimal late toxicity. Local disease control is encouraging, with acceptable treatment-related complications, when treating with the described two-phase IMRT treatment technique.

Lindsay M. Burt, Ying Hitchcock; Huntsman Cancer Institute, University of Utah

PURPOSE: To review radiotherapy (RT) technique and outcomes for definitive RT or chemoradiotherapy (CRT) for unresectable, very locally advanced, or medically inoperable paranasal sinus (PNS) or nasal cavity (NC) cancer at a single institution.

METHODS: Between 1998 and 2010, there were 11 patients with unresectable, very locally advanced, or medically inoperable PNS/NC cancers treated with definitive CRT (7) or RT alone (4) at the University of Utah. There were 10 males and 1 female, with a mean age of 57.3 years (range: 28–75 yr). CRT was given to stage IVA (5) and stage IVB (2) patients, and RT alone was given to stage II (1), stage III (1), and stage IVA (2) patients. One patient was treated with a three-dimensional (3D) conformal technique, and 10 were treated with intensity-modulated RT (IMRT). The median dose was 70.2 Gy (range: 70–72.4 Gy). In order to adapt to tumor shrinkage and prevent critical structures from receiving a high dose due to tumor regression and weight loss, most patients underwent two treatment planning phases, with a resimulation at a dose of 45–50 Gy. One patient received a boost of 11 Gy using stereotactic radiosurgery (SRS) following 70.2 Gy external beam RT (EBRT). The most common chemotherapy agent was cisplatin at 40 mg/m2, given on a weekly basis for 6–7 cycles. A flexible nasal endoscopy with a biopsy was performed 3 months posttreatment to evaluate tumor response.

RESULTS: There was a median follow-up of 39 months (range: 1–70 mo). Six patients underwent a debulking surgery. Overall, six (55%) patients remained disease-free, two (18%) developed local recurrences, one (9%) developed regional recurrence, and 2 (18%) developed distant metastasis. Local control was seen in 9 of 11 (81.8%) patients. The treatment was well tolerated, with only one patient experiencing a grade 3 late toxicity (trismus), two patients experiencing grade 2 late toxicities (cataract, retinal detachment, and trismus), and five patients experiencing grade 1 late toxicities (dysgeusia, dry mouth, fibrosis, skin telangiectasia, and nasal congestion). Three patients had no late toxicities.

CONCLUSION: Definitive CRT or RT is feasible for unresectable, very locally advanced, or medically inoperable PNS/NC cancer with minimal late toxicity. Local disease control is encouraging, with acceptable treatment-related complications, when treating with the described two-phase IMRT treatment technique.

Proceedings of the 97th Annual Meeting of the American Radium Society- americanradiumsociety.org