title: Clinical impact of margin reduction on late toxicity and short-term biochemical control for patients treated with daily on-line image guided IMRT for prostate cancer.
abstract: To evaluate the impact of PTV reduction when delivering image-guided IMRT (IG-IMRT) for patients with prostate cancer. Between 2001 and 2007, 165 men were treated with daily IG-IMRT using a 3D ultrasound-based system. Median dose prescribed to the prostate was 78 Gy [74 Gy-78 Gy]. Patients were stratified regarding the CTV to the PTV margin: group A (n=87)=5mm or group B (n=78)=10mm. Late toxicity was scored using the CTC v3.0 scale. Biochemical progression-free survival (bPFS) was calculated using the Phoenix definition. Grade 2 genitourinary toxicity was 7.0% for group A and 6.6% for group B (p=1.00). Grade 2 gastrointestinal toxicity was 1.2% and 2.6% (p=0.38). With a median follow-up of 38.3 months [5.25-87.3], bPFS at 3 years was 92.5% [82.4%-96.9%] in group A and 94.3% [85.5%-97.8%] in group B (p=0.84). IG-IMRT yielded very low rates of late toxicity. Margin had impact neither on short-term bPFS nor late toxicity.
authors: Department of Radiation Oncology, Centre Georges Francois Leclerc, Dijon, France. gcrehange@cgfl.fr
authors: Gilles
authors: G
authors: Crehange
authors: Celine
authors: C
authors: Mirjolet
authors: Melanie
authors: M
authors: Gauthier
authors: Etienne
authors: E
authors: Martin
authors: Gilles
authors: G
authors: Truc
authors: Karine
authors: K
authors: Peignaux-Casasnovas
authors: Caroline
authors: C
authors: Azelie
authors: Franck
authors: F
authors: Bonnetain
authors: Suzanne
authors: S
authors: Naudy
authors: Philippe
authors: P
authors: Maingon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000009:adverse effects* / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods