Dose escalation with IMRT was associated with improved cancer control in intermediate- and high-risk patients in comparison with 3D-CRT, without compromising toxicity.

No abstract

Sufficient dose coverage of target volumes was not achieved for all patients. Reducing of safety margin is not acceptable. Initial rectal and bladder volumes cannot be considered representative for subsequent treatment.

Rectum and bladder are the crucial organs at risk for curative radiation therapy of localized prostate cancer. We analyzed the incidence, profile and time course of late rectal radiation toxicity. A total of 320 patients with T1-3 prostate cancer were treated with three-dimensional conformal radiation therapy (3D-CRT). The prescription dose was 70 Gy for T1 and T2 patients (n ¼ 230) and 74 Gy for patients with locally advanced T3 tumors (n ¼ 90). Late rectal toxicity was graded according to the Fox Chase modification of the Radiation Therapy Oncology Group (RTOG) and Late Effects Normal Tissue Task Force (LENT) criteria. The median follow-up time was 6.2 years (range 0.2-10.7 years). At 5 years, the risk for the development of grade 2 and 3 rectal toxicities was 15.6 and 7.0%, respectively. All new cases of grade 2 and 3 rectal toxicities were observed within 5 years after treatment. Prevalence of grade 2 and 3 rectal symptoms showed fluctuation with maximum at 1.5 years and the minor peak at 4.5 years. Toxicity profile changed significantly over time. The proportion of rectal bleeding within grade 2 and 3 toxicity decreased from 85% at 1.5 years to 46% at 4.5 years. Conversely, the proportion of fecal incontinence among grade 2 and 3 rectal symptoms gradually increased (0% at 1.5 years vs 27% at 4.5 years). Late rectal radiation toxicity represents a dynamic process. Rectal bleeding decreases and fecal incontinence increases over time.

The purpose of this study was to compare two different styles of prostate IGRT: bony landmark (BL) setup vs. fiducial markers (FM) setup. Twenty‐nine prostate patients were treated with daily BL setup and 30 patients with daily FM setup. Delivered dose distribution was reconstructed on cone‐beam CT (CBCT) acquired once a week immediately after the alignment. Target dose coverage was evaluated by the proportion of the CTV encompassed by the 95% isodose. Original plans employed 1 cm safety margin. Alternative plans assuming smaller 7 mm margin between CTV and PTV were evaluated in the same way. Rectal and bladder volumes were compared with initial ones. While the margin reduction in case of BL setup makes the prostate coverage significantly worse (p=0.0003, McNemar's test), in case of FM setup with the reduced 7 mm margin, the prostate coverage is even better compared to BL setup with 10 mm margin (p=0.049, Fisher's exact test). Moreover, partial volumes of organs at risk irradiated with a specific dose can be significantly lowered (p<0.0001, unpaired t‐test). Reducing of safety margin is not acceptable in case of BL setup, while the margin can be lowered from 10 mm to 7 mm in case of FM setup.PACS numbers: 87.55.dk, 87.55.km, 87.55.tm

Objectives:To retrospectively compare late toxicity of conventional-dose three-dimensional conformal radiation therapy (3D-CRT) and high-dose intensity-modulated radiation therapy (IMRT) for prostate cancer. Methods: A total of 340 patients with T1-3 prostate cancer were treated with 3D-CRT (n = 228) and IMRT (n = 112). The median follow-up time was 5.9 years and 3.0 years, respectively. The prescription dose was 70 Gy for 3D-CRT and 78 Gy for IMRT. Late gastrointestinal (GI) and genitourinary (GU) toxicities were graded according to the Fox Chase modification of the Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. Results: There was no difference between 3D-CRT and IMRT in the incidence of GI and GU toxicity at 3 years. On multivariate analysis, transurethral resection of prostate/open transvesical prostatectomy (TURP/TVPE) for benign prostatic hyperplasia, carried out before radiotherapy, significantly increased the risk of Grade Ն2 GU toxicity (risk ratio 1.88). Among patients who experienced TURP/TVPE, the 5-year actuarial likelihood of Grade 2-3 urinary incontinence was 23%, compared with 9% for those without prostate surgery (P = 0.01). Conclusions: Tolerance of 3D-CRT and IMRT was similar, despite the use of high radiation dose with IMRT. Previous TURP/TVPE increased the risk of GU toxicity.

SIB enables dose escalation up to 82 Gy with a lower rate of gastrointestinal toxicity grade 3 in comparison with 3D-CRT up to 74 Gy.

Introduction: Prostate cancer with a Gleason score (GS) of 8–10 is linked to a higher risk of recurrence and progression. The aim of this paper is to evaluate treatment results of our high-risk patient cohort.Patients and Methods: The cohort of 42 patients with radical prostatectomy (RP) specimen histology GS 8–10 was assessed. The patients were followed up after RP and radiotherapy (RT) was delivered in case of a biochemical relapse. Adjuvant radiotherapy (aRT) was delivered only in case of a positive surgical margin (PSM). The following parameters were evaluated: biochemical progression-free survival (BPFS), overall survival (OS) and cancer-specific survival (CSS). The second objective was to evaluate adverse effects of RP and RT. Results: The median follow-up time was 88 months (18–168). RP led to BPFS in 16 patients (38%). Five patients with PSM underwent aRT and 20 underwent salvage radiotherapy (sRT). One patient died of myocardial infarction and 1 patient died of metastatic disease. Skeletal metastases were recorded in 2 patients. The BPFS in RP combinations with sRT or aRT was reached in 29 patients (69%). The OS and CSS in our cohort reached 95 and 98%, respectively. Conclusion: Management with aRT only in PSM was very effective, according to our retrospective study.