R. Jeroen A. van Moorselaar

Clinical feasibility study for the use of implanted gold seeds in the prostate as reliable positioning markers during megavoltage irradiation

BACKGROUND AND PURPOSEnThe aim of this study was to assess the feasibility of using gold seed implants in the prostate for position verification, using an a-Si flat panel imager as a detector during megavoltage irradiation of prostate carcinoma. This is a study to guarantee positioning accuracy in intensity-modulated radiotherapy.nnnMETHODS AND MATERIALSnTen patients with localized prostate carcinoma (T2-3) received between one and three fiducial gold markers in the prostate. All patients were treated with 3-D conformal radiotherapy with an anterior-posterior (AP) and two lateral wedge fields. The acute gastrointestinal (GI) and genitourinary (GU) toxicities were scored using common toxicity criteria scales (CTC). Using three consecutive CT scans and portal images obtained during the treatment we have studied the occurrence of any change in prostate shape (deformation), seed migration and the magnitude of translations and rotations of the prostate.nnnRESULTSnWe observed no acute major complications for prostate irradiation regarding the seed implantation. The maximum acute GU toxicity grade 2 (dysuria and frequency) was observed in seven patients during the treatment. The maximum grade 2 (diarrhoea) was scored in two patients regarding the acute GI toxicities. No significant prostate deformation could be detected in the consecutive CT scans. It appeared that the distances between the markers only slightly changed during treatment (S.D. 0.5 mm). Random prostate translations were (1 S.D.) 2.1, 3.2 and 2.2 mm in the lateral (LR), AP and cranial-caudal (CC) directions, respectively, whereas systematic translations were 3.3, 4.8 and 3.5 mm in the LR, AP and CC directions, respectively. Random prostate rotations were (1 S.D.) 3.6, 1.7 and 1.9 degrees around the LR, AP and CC axis, respectively, whereas systematic rotations were 4.7, 2.0 and 2.7 degrees around the LR, AP and CC axis, respectively.nnnCONCLUSIONSnWe found that the fiducial gold seeds are a safe and appropriate device to verify and correct the position of prostate during megavoltage irradiation. The amount of seed migration and prostate deformation is far below our present tumour delineation accuracy.

Measurements and clinical consequences of prostate motion during a radiotherapy fraction.

PURPOSEnHere we study the magnitude of prostate motion during the delivery of a radiotherapy fraction. These motions have clinical consequences for on-line position verification and the choice of margins around the target volume.nnnMETHODS AND MATERIALSnWe studied the motion of the prostate for 10 patients during 251 radiotherapy treatment fractions by assessing the position of implanted gold markers. Gold markers of 1 mm diameter and 5 mm length were implanted in the prostate before the start of the radiotherapy. We obtained movies during each fraction using an a-Si flat-panel imager. The markers could be detected in separate frames using a marker extraction kernel.nnnRESULTSnMarker displacements as large as 9.5 mm were detected in one fraction. The motion of the prostate is greatest in the caudal-cranial and the anterior-posterior directions. Within a time window of 2 to 3 min, deviations from the initial marker position, averaged over all patients, are 0.3 +/- 0.5 mm and -0.4 +/- 0.7 mm in the anterior-posterior and caudal-cranial directions, respectively.nnnCONCLUSIONSnIt appeared that on average, the intrafraction prostate motions did not result in margins larger than 1 mm, provided that the position verification is performed at time intervals of 2 to 3 min. Only for some patients performing more frequent position verification or adding extra margins of 2 to 3 mm is required to account for intrafraction prostate motions.

Comparison of megavoltage position verification for prostate irradiation based on bony anatomy and implanted fiducials.

PURPOSEnThe patient position during radiotherapy treatment of prostate cancer can be verified with the help of portal images acquired during treatment. In this study we quantify the clinical consequences of the use of image-based verification based on the bony anatomy and the prostate target itself.nnnPATIENTS AND METHODSnWe analysed 2025 portal images and 23 computed tomography (CT) scans from 23 patients with prostate cancer. In all patients gold markers were implanted prior to CT scanning. Statistical data for both random and systematic errors were calculated for displacements of bones and markers and we investigated the effectiveness of an off-line correction protocol.nnnRESULTSnStandard deviations for systematic marker displacement are 2.4 mm in the lateral (LR) direction, 4.4 mm in the anterior-posterior (AP) direction and 3.7 mm in the caudal-cranial direction (CC). Application of off-line position verification based on the marker positions results in a shrinkage of the systematic error to well below 1 mm. Position verification based on the bony anatomy reduces the systematic target uncertainty to 50% in the AP direction and in the LR direction. No reduction was observed in the CC direction. For six out of 23 patients we found an increase of the systematic error after application of bony anatomy-based position verification.nnnCONCLUSIONSnWe show that even if correction based on the bony anatomy is applied, considerable margins have to be set to account for organ motion. Our study highlights that for individual patients the systematic error can increase after application of bony anatomy-based position verification, whereas the population standard deviation will decrease. Off-line target-based position verification effectively reduces the systematic error to well below 1 mm, thus enabling significant margin reduction.

Alfuzosin 10 mg once daily improves sexual function in men with lower urinary tract symptoms and concomitant sexual dysfunction

Associate Editor

Long-term experience with transrectal and transperineal implantations of fiducial gold markers in the prostate for position verification in external beam radiotherapy; feasibility, toxicity and quality of life

BACKGROUND AND PURPOSEnThis study presents an overview of the experience with transrectal and transperineal implantations of fiducial markers for position verification in prostate radiotherapy, regarding the practical feasibility, procedure-related toxicity and influence on quality of life (QoL).nnnMATERIAL AND METHODSnSince 2001, 914 patients scheduled for intensity-modulated radiotherapy (IMRT) have received gold markers in the prostate. The incidence of severe toxicity, defined by the CTCAE v3.0, was evaluated retrospectively. The influence on QoL was measured prospectively in 36 patients using a combination of three validated questionnaires: the Rand-36, the EORTC QLQ-C30(+3) and the prostate cancer-specific EORTC QLQ-PR25. Next, the incidence of marker migration was assessed.nnnRESULTSnFrom 2001 to 2005, 402 patients received markers via the transrectal route. Two of these patients developed urosepsis (grade 3 toxicity). Since 2005, 512 patients received markers via the transperineal route. No grade 3 or 4 toxicity occurred in this group. No significant and clinically relevant differences were found in QoL between pre- and post-implant measures. In 5 patients marker migration led to discontinuation of the marker-based IMRT.nnnCONCLUSIONSnClinical use of transperineal-implanted fiducial gold markers for position verification in external beam radiotherapy for prostate cancer is a feasible and safe procedure without influencing patients QoL.

Alfuzosin 10 mg once daily for treating benign prostatic hyperplasia: a 3-year experience in real-life practice

To assess the 3‐year efficacy and safety of the selective α1‐blocker alfuzosin at 10u2003mg once daily in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) in ‘real‐life practice’. The influence of treatment response on the risk of acute urinary retention (AUR) and BPH‐related surgery was also analysed.

Long-term efficacy and safety of alfuzosin 10 mg once daily: a 2-year experience in ‘real-life’ practice

To assess the 2‐year efficacy and safety of alfuzosin 10u2003mg once daily, a selective α1‐adrenoceptor antagonist, in men complaining of lower urinary tract symptoms (LUTS) suggestive of benign prostate hyperplasia (BPH), in ‘real life’ practice.

Intraprostatic testosterone and dihydrotestosterone. Part I: concentrations and methods of determination in men with benign prostatic hyperplasia and prostate cancer.

Whats known on the subject? and What does the study add?

Intraprostatic testosterone and dihydrotestosterone. Part II: concentrations after androgen hormonal manipulation in men with benign prostatic hyperplasia and prostate cancer

Whats known on the subject? and What does the study add?

A new concept for non-invasive renal tumour ablation using real-time MRI-guided radiation therapy

Study Type – Therapy (case series)u2028Level of Evidenceu20034