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The purpose of benchmarking is to settle improvement processes by comparing the activities to quality standards. The proposed methodology is illustrated by benchmark business cases performed inside medical plants on some items like nosocomial diseases or organization of surgery facilities. Moreover, the authors have built a specific graphic tool, enhanced with balance score numbers and mappings, so that the comparison between different anesthesia-reanimation services, which are willing to start an improvement program, is easy and relevant. This ready-made application is even more accurate as far as detailed tariffs of activities are implemented.

Resume Objectifs Evaluer la frequence du phenomene de « rebond » (elevation secondaire transitoire de la concentration serique du PSA) du PSA apres curietherapie de prostate et rechercher une correlation entre le rebond et les parametres cliniques et dosimetriques. Evaluer comment ce rebond du PSA peut mimer les criteres de rechute biochimique. Patients et methodes De mai 1998 a mai 2005, 1000 patients ont eu une curietherapie pour un cancer localise de la prostate de bas risque a l'institut Curie. Apres l'implantation, un dosage serique de PSA a ete realise tous les six mois. Nous avons defini le « rebond » comme toute augmentation du PSA d'au moins 0,1 ng/ml, suivie d'une diminution spontanee de celui-ci. Nous avons utilise les criteres de rechute biochimique definis par le consensus de l'ASTRO (trois elevations successives de la concentration serique de PSA), et analyse les correlations entre les rebonds de PSA, les parametres cliniques et dosimetriques, en analyse multifactorielle. Pour evaluer le phenomene de rebond avec un recul suffisant, cette serie a donc porte sur les patients traites par la technique en temps reel, avec grains libres d'125I (Isoseed, Bebig), jusqu'a decembre 2001. Dans ce groupe de 295 patients, la duree moyenne de suivi a ete de 40,3 mois (9–66 mois). Resultats Dans notre serie, 161 patients (55 %) ont eu une elevation transitoire de la concentration serique de PSA (« rebond ») d'au moins 0,1 ng/ml ; 145 patients (49 %) un rebond d'au moins 0,2 ng/ml, 93 patients (32 %) un rebond d'au moins 0,4 ng/ml, 43 patients (15 %) un rebond d'au moins 1 ng/ml. Le delai moyen d'apparition de cette elevation a ete de 19 mois (6–58), et la duree moyenne de six mois. L'amplitude moyenne de l'elevation a ete de 0,8 ng/ml (0,1–4,1 ng/ml). Trente-deux patients, soit 11 % du nombre total des patients, ont eu trois elevations successives du PSA avec un intervalle significatif entre les dosages (trois mois) et etaient donc en situation de rechute biochimique selon les criteres de l'ASTRO. Parmi ces 32 patients, 18 (56 %) ont vu leur PSA se normaliser completement et spontanement. Au total, seuls dix patients ont vu leur concentration serique de PSA continuer a augmenter et ont donc eu une authentique recidive biochimique. Pour les quatre derniers patients, la situation restait encore ambigue compte tenu des fluctuations persistantes du PSA et du recul insuffisant. En analyse multifactorielle, l'âge inferieur a 70 ans (p Conclusions Dans notre serie, 32 % des patients ont eu un rebond de la concentration serique de PSA d'au moins 0,4 ng/ml, en accord avec les donnees de la litterature. Ce rebond a ete observe jusqu'a cinq ans apres l'implantation, a atteint jusqu'a 4 ng/ml, et a dure six mois en moyenne. Parmi les 32 patients avec les criteres de rechute biochimique de l'ASTRO, 18 (56 %) avaient en fait un simple rebond. Les criteres de l'ASTRO ne sont donc pas adaptes au suivi biolochimique precoce apres curietherapie de prostate, et les resultats de la curietherapie doivent etre evalues avec un recul suffisant pour tenir compte du phenomene de rebond. Cela a des consequences cliniques pratiques evidentes, sur le diagnostic de recidive et la decision d'un eventuel traitement complementaire.

To assess the frequency and features of the PSA bounce phenomenon in a series of patients treated with permanent implant brachytherapy for prostate cancer, and to evaluate the percentage of cases in which this bounce could have mimicked a biochemical relapse according to the American Society for Therapeutic Radiology and Oncology consensus criteria.From January 1999 to December 2001, 295 patients were treated with a permanent prostate implantation (real-time technique, with free (125)I seeds) by the Paris Institut Curie/Hospital Cochin/Hospital Necker Paris group. Duration of followup is 40.3 months (9-66 months). PSA level was reported at intervals not exceeding 6 months. Bounce was defined by temporary elevation in PSA level, followed by a spontaneous decrease.In our series, 161 patients (55%) showed a transitory PSA increase (bounce) of at least 0.1 ng/mL; 145 patients (49%) a bounce of 0.2 ng/mL; 93 patients (32%) a bounce of 0.4 ng/mL; and 43 patients (15%) a bounce of at least 1 ng/mL. Mean PSA bounce was 0.8 ng/mL (0.1-4.1), and mean time to bounce was 19 months. Thirty-two patients (11% of total) presented three successive PSA increases, and therefore were to be considered as experiencing a biochemical relapse according to the American Society for Therapeutic Radiology and Oncology (ASTRO) consensus criteria. Among those 32 patients, 18 (56%) subsequently showed, without any treatment, a complete normalization of their PSA. In multivariate analysis, age70 (p0.0001) and D90200Gy (p0.003) were identified as independent factors for a PSA bounce of at least 0.4 ng/mL.The observed rate of 32% of patients showing a PSA bounce of at least 0.4 ng/mL in our series is in good agreement with what has been previously reported in the literature. Among 32 patients fulfilling the classical ASTRO criteria for a biochemical relapse, 18 (56%) subsequently showed a spontaneous PSA decrease, questioning the ASTRO consensus for the biochemical followup of patients undergoing permanent implant prostate brachytherapy.

Purpose To describe the results of 125I plaque brachytherapy of uveal melanomas anterior to the equator in terms of local control and the associated complications while trying to identify their risk factors (patients' demographic data, ocular, and tumour characteristics). Methods Retrospective analysis of a series of patients treated by 125I between 1990 and 2000 in a single institution. The main outcome measures are evaluation of local tumour control and complications associated with 125I plaque brachytherapy of these melanomas. Results During the study period, 136 patients were treated for an anterior tumour. The median follow-up was 62 months. The overall 5-year survival rate was 88.3%, the 5-year metastasis rate was 4% and the local recurrence rate was 1.5%. The mean final visual acuity was 20/40. The ocular complications most frequently observed at 5 years were cataract (50.3%), maculopathy (18.3%), intraocular inflammation (19.3%), and glaucoma (10.6%). Optic neuropathy, retinal detachment, keratitis, and intravitreous haemorrhage were also described. Risk factors for worse survival were age greater than 65 years and initial tumour thickness greater than 4 mm. Risk factors for the development of cataract were age more than 65 years old, male gender, and tumour diameter of more than 10 mm. Risk factors for intraocular inflammation were tumour thickness of more than 4 mm and invasion of the ciliary body. Conclusions The use of 125I plaque brachytherapy to treat melanomas situated anterior to the equator allows good local and systemic control with a low rate of macular and optic disc complications. The most frequent complication was cataract formation.

Resume Dans les dix dernieres annees, la curietherapie prostatique par implantation permanente s’est imposee comme une reelle alternative therapeutique dans le traitement des cancers localises de la prostate. La publication recente de resultats a 10-12 ans montre des resultats equivalents, pour une population selectionnee, a ceux de la chirurgie et de la radiotherapie conformationnelle, avec un faible taux de complications. Les criteres de selection ont bien ete definis par les societes savantes : tumeur classee T1 ou T2, concentration serique de PSA

This paper presents the axial ratio beamwidth results obtained by different sequentially rotated microstrip patch antenna sub-array configurations. Simplified formulae of electrical radiation pattern allow a direct polarization estimation. To validate these formulae, a comparison with a rigorous calculation code using the Finite Difference Time Domain method (F.D.T.D.), through same cases simulated, gives good agreement. Finally, excitation errors introduced in simple analytical expressions are taken into account for two particular sub-arrays.

The purpose of benchmarking is to settle improvement processes by comparing the activities to quality standards. The proposed methodology is illustrated by benchmark business cases performed inside medical plants on some items like nosocomial diseases or organization of surgery facilities. Moreover, the authors have built a specific graphic tool, enhanced with balance score numbers and mappings, so that the comparison between different anesthesia-reanimation services, which are willing to start an improvement program, is easy and relevant. This ready-made application is even more accurate as far as detailed tariffs of activities are implemented.

Whereas it has been proposed almost one century ago, brachytherapy for prostate cancer has only recently emerged, especially thanks to endorectal echography, allowing to visualize seed implantation, to the development of seeds for permanent delivery and of micro-sources for high-dose rate delivery, and also to the development of three-dimension dosimetry programs allowing real-time implantations. For selected patients with localized prostate cancer (PSA10, Gleason7, no extracapsular extension, volume50-60 g), prostate brachytherapy with permanent implants (iodine 125 or, less frequently, palladium 103) gives results which appear at 10-15 years comparable to those of surgery. Incontinence and impotence rates appear lower than those of classical surgery. However, the first post-implant months are usually accompanied by urinary toxicity that should not be minimized. High-dose rate brachytherapy (HDR) could find its indications, in combination with conformal radiotherapy, in the treatment of more advanced forms, presenting an intermediate risk. It could also be an alternative to brachytherapy with permanent implants for the low-risk forms mentioned above, especially in developing countries where the cost of radioactive seeds slows down the use of this technique. Brachytherapy for prostate cancer should, therefore, find more and more indications, because of the increased incidence of prostate cancer, due to population ageing, of the increased proportion of localized forms, due to better detection, of the patient's request for less toxicity, and of the expecting lowering of the costs, which are now equivalent to those of surgery and should further lower.

To assess the frequency of the PSA "bouncing" phenomenon after a significant follow-up in a series of patients treated by permanent implant brachytherapy for a prostate cancer. To look for the clinical and dosimetric parameters possibly linked to this transitory secondary PSA increase. To evaluate in which percentage of cases this bouncing could have mimicked a biochemical relapse according to the ASTRO consensus criteria.From January 1999, to December 2001, 295 patients were treated by a permanent prostate implantation (real-time technique, with free (125)I seeds- Isoseed Bebig-) by the Institut Curie-Hôpital Cochin-Hôpital Necker Paris group. The mean follow-up is 40.3 months (9-66 months). The PSA level was regularly checked, at least every 6 months. We defined as a "bouncing" all increase in PSA, starting at 0.1 ng/ml, subsequently followed by a spontaneous (without any treatment) decrease, with return to the previous level or lower. We particularly focused on the patients fulfilling the criteria for a biochemical relapse according to the ASTRO consensus (Three successive increases in PSA). A multivariate analysis tried to identify independent factors among the usual clinical and dosimetric parameters.In our series, 161 patients (55%) showed a transitory PSA increase (bouncing) of at least 0.1 ng/ml; 145 patients (49%) a bouncing of 0.2 ng/ml, 93 patients (32%) a bouncing of 0.4 ng/ml and 43 patients (15%) a bouncing of at least 1 ng/ml. Mean PSA bounce was 0.8 ng/ml (0.1-4.1), and mean time to bounce was 19 months. Thirty-two patients (11% of the total number) presented three successive PSA increases with a significant (3 months) interval between the dosages, and therefore were to be considered as being in biochemical relapse according to the ASTRO consensus criteria. Actually, among those 32 patients, 18 (56%) subsequently showed a complete normalization of their PSA, without any treatment. Ten patients went on increasing their PSA, and were considered to be really in biochemical relapse. For the last 4 patients, the situation still remains ambiguous. In multivariate analysis, age70 years (P0.00001) and D90200 Gy (P0.003) were identified as independent factors for a PSA bouncing of at least 0.4 ng/ml.The observed rate of 32% of patients showing a PSA bouncing of at least 0.4 ng/ml in our series is in good agreement with what has been previously reported in the literature. Age70 years and D90200 Gy were found to be independent factors predicting for such a secondary transitory increase in PSA. Interestingly, among 32 patients fulfilling the classical criteria of the ASTRO for a biochemical relapse, 18 (56%) subsequently showed a spontaneous PSA decrease, demonstrating that the ASTRO consensus is not well adapted to the biochemical follow-up of our patients undergoing permanent implant prostate Brachytherapy.

Real-time ultrasound (US)-based dosimetry performed during (125)I loose seed implantation provides the radiation oncologist with an estimation of the dose distribution at seed insertion. However, for a number of reasons, this distribution may not reflect the real (reference) dosimetry as determined by subsequent CT, usually performed 1-2 months after implantation. The present study compared the two dosimetry data sets (US and CT) to evaluate how predictive extemporaneous US-based dosimetry can be of the real dose distribution.A total of 450 patients with prostate cancer were treated with loose (125)I seed implantation between June 1999 and October 2002 by the Institut Curie/Hospital Cochin (Paris) Group. The mean patient age was 65 years. Most patients (74%) had Stage T1c; the stage did not exceed T2b for the others. All patients had a prostate-specific antigen level of15 ng/mL and was10 ng/mL for 72%; 84% had a Gleason score ofor =6 and did not exceed 7 for the others; and 56% were treated with neoadjuvant hormonal therapy for a mean of 4.3 months. All patients were treated with loose seed implantation. Real-time US-based dosimetry was performed intraoperatively for all patients. CT-based dosimetry was performed 2 months after implantation, using the VariSeed software. The minimal dose to 90% of the outlined volume (D(90)) and percentage of volume receiving at least 100% of the prescribed dose (V(100)) were calculated with the two methods and compared for all patients.On CT-based dosimetry, the D(90) was found to beor =145 Gy (range, 115-240 Gy) in all patients except one. A large majority (86%) of patients showed a CT-based V(100) of95%, and 48% had a V(100) of98%. The mean CT-based D(90)/US-based D(90) ratio was 1.0 (range, 0.66-1.33). For 89% of the patients, the difference between the two values was20% and for 62% was10%. The mean CT-based V(100)/US-based V(100) ratio was 0.98 (range, 0-1.02), with 89% of patients showing a difference of5%.Our results indicate that the D(90) and V(100) values obtained intraoperatively with our real-time US-based dosimetry are in reasonable agreement with the subsequent values obtained with CT-based dosimetry performed 2 months after implantation. Recent innovations in our dose planning software allowed better control of the longitudinal seed position and could still improve the correlation between real-time US-based dosimetry and the subsequent CT-based dose distribution.

In the last decade, brachytherapy emerged as a particularly appealing new way ot treating localized prostate cancer. Recently published 10-12 years biochemical control results appear to be superimposable to the best percentages achieved by surgery or conformal radiotherapy, with a small percentage of complications. This applied to severely patients. Only patients with T1/T2, PSA10 ng/mL, and Gleason score7 should be proposed such a treatment. The potential benefit of exploring patients with a endorectal coil MRI is being evaluated. The number of positive biopsies is also a parameter which should probably be considered in the therapeutic choice. Moreover, a prostate volume60 g, hip mobility limitations, a urinary obstructive syndrome and previous transurethral resection lead to difficulties in technical implantation and therefore must be taken into account when discussing brachytherapy. In conclusion, for adequately selected patients, brachytherapy offers a particularly applied alternative to surgery and external radiotherapy, with satisfactory long term biochemical control rates and limited complications.