High-Dose Rate Brachyther-apy in the Treatment of Early Stages of Penile Carcinoma.

BACKGROUND: Interstitial low dose rate brachyther-apy is established organ spar-ing treatment of T1- T2 penile carcinoma. Experience with high-dose rate brachyther-apy is limited in this indication. MATERIALS AND METHODS: Twenty-six patients with early penile carcinoma were treated by high-dose rate brachyther-apy at dose 18 × 3 Gy per fraction twice daily between 2002- 2018 at the Department of Oncology and Radiother-apy, University Hospital in Hradec Kralove. Breast interstitial brachyther-apy template was used for fixation and precise geometry reconstruction of stainless hollow needles. RESULTS: Median follow up was 85 months (range 7- 200 months). Acute reaction usually consisted of grade 2 mucositis that dissolved dur-ing 8 weeks after the treatment. Local recurrence occurred in 6 patients, 5 of them were successfully treated with partial amputation. One patient had a nodal recurrence successfully salvaged by lymphadenectomy. One patient developed necrosis of the glans requir-ing partial amputation. Currently, there are 24 patients alive without signs of dis-ease. One patient died of cardiac comorbidity, one died of duplicate lung cancer. Nineteen patients have a preserved penis (73%), 18 of them sexually active before treatment report satisfactory intercourse. CONCLUSION: Hyperfractionated interstitial high-dose rate brachyther-apy with 18 × 3 Gy per fraction twice daily is a promis-ing method in selected patients with penile carcinoma and deserves further evaluation in a larger prospective study. Key words penile neoplasms -  conservative treatment -  brachyther-apy This work was supported by programm Progres Q40. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 8. 1. 2019 Accepted: 15. 1. 2019.

Quantitative evaluation of the benefit of fiducial image-guidance for prostate cancer intensity modulated radiation therapy using daily dose volume histogram analysis.

To quantitatively evaluate the extent to which fiducial-based image-guidance improves dose coverage of the target volume and sparing of critical organs for prostate cancer patients treated with intensity modulated radiotherapy (IMRT) and determination of planning margins by original approach of detailed daily dose volume histogram (DVH) and patient's position correction analysis. Sixty-two patients divided in two groups (clinical target volume (CTV) → planning target volume (PTV) margin 10 and 7 mm) were treated with IMRT using implanted fiducial markers. Each patient's treatment fraction was recalculated as it would have been treated without fiducial-guided positioning. For both plans (IGRT and non-IGRT), equivalent uniform doses (EUD), maximal and minimal doses for target volumes, normal tissue complication probability (NTCP), maximum and mean doses for organs at risk and the whole DVH differences were assessed. In the group with 10 mm margins, the only significant difference was worse rectal NTCP by 4.5%, but the CTV dose coverage remained at the same level. Recalculated plans with 7 mm margin could not achieve the prescribed target volume coverage, and the EUD decreased by 3.7 and 0.6 Gy for PTV and CTV, respectively. Desired CTV → PTV margin for non-IGRT plans should be no lower than 12 mm to guarantee 95% instances when delivered dose to CTV maintain as planned, for IGRT plans decrease this requirement to 2 mm. Prostate IMRT strategies involving margin reduction below 7 mm require image-guidance to maintain the planned dose coverage. Using fiducial-based image-guidance and large margins seems to be superfluous.

[Five-year results of IMRT for prostate cancer - toxicity]. / Petileté výsledky IMRT karcinomu prostaty - toxicita.

BACKGROUND: Intensity modulated radiotherapy (IMRT) plays a crucial role in the treatment of prostate cancer thanks to its capacity for healthy tissue sparing. This work reports on the acute and late toxicity rates among 233 patients treated with high-dose IMRT. MATERIAL AND METHODS: From June 2003 to December 2007, 233 men with clinically localized prostate cancer underwent radical radiotherapy. One hundred sixty patients were treated with IMRT to the prostate and the base of seminal vesicles to 78 Gy in 39 fractions, 73 patients underwent simultaneous integrated boost. Prescribed doses were 82 Gy and 73,8 Gy in 41 fractions to the prostate and seminal vesicles, respectively. Late toxicity was evaluated prospectively using a RTOG/FC-LENT score. RESULTS: Thirty patients (12.8%) experienced acute Grade 2 gastrointestinal (GI) toxicity. No acute Grade 3 or 4 GI toxicity developed. Forty two patients (18.1%) experienced acute Grade 2 genitourinary toxicity and 23 patients (9.9%) had Grade 3 GU toxicity. Grade 4 Genitourinary toxicity was observed in nine (3.8%) patients, due to a need of short-term urinary catheterization. With a median follow-up of 49.2 months, the estimated 5-year cumulative incidence of Grade 2 gastrointestinal toxicity was 22.4%. The estimated 5-year cumulative incidence of Grade 2 genitourinary toxicity was 17.7%. CONCLUSION: Intensity modulated radiotherapy enables dose escalation to 78-82 Gy with an acceptable toxicity.

[Five-year results of IMRT for prostate cancer - tumor control]. / Petileté výsledky IMRT karcinomu prostaty - kontrola nádoru.

BACKGROUND: Intensity-modulated radiation therapy (IMRT) is the method of choice in external-beam radiotherapy tolocalized prostate cancer. This work analyses five year results of IMRT with a dose of 78/82 Gy. PATIENTS AND METHODS: From June 2003 to December 2007, the IMRT technique was employed to treat 233 patients with T1-3 N0 M0 prostate cancer. It was supplemented by hormone therapy especially in high-risk patients. Two IMRT techniques were applied - IMRT with a dose of 78 Gy in 39 fractions to prostate and seminal vesicles (SV) (IMRT 78) and IMRT with simultaneous integrated 82 Gy boost to prostate concurrently with 73,8 Gy in 41 fractions to SV (IMRT SIB 82). The IMRT 78 technique was used in 160 patients (69%). Seventy-three (31%) patients with intermediate (IR) or high-risk (HR) prostate cancer without SV involvement were treated with IMRT SIB 82 technique. The PSA relapse was defined as an increase in PSA of at least 2.0 ng/mL above the nadir or in comparison to the value at the initiation of hormone therapy. Clinical relapse was defined as an occurence of distant metastases and/or local recurrence. RESULTS: The median follow-up of our patients´ population was 4.3 years (range 0.6-8.9 years). The estimated 5-year PSA relapse-free survival in low-risk (LR), IR and HR patients was 86%, 89% and 83%, respectively (p = NS). In a multivariate analysis, Gleason score (GS) 8-10 was associated with significantly higher risk of PSA relapse (RR 2.76), while higher age at the time of diagnosis significantly decreased the PSA relapse risk (RR 0.94). The estimated 5-year clinical relapse-free survival in LR, IR and HR patients was 100%, 99% and 95%, respectively (p = NS). In a univariate analysis, both GS and PSA had a significant impact on the 5-year clinical relapse-free survival - GS 2-7 97 % vs GS 8-10 88 % (p = 0.03), PSA 20 98 % vs PSA > 20 85 % (p < 0.01). CONCLUSION: Treatment of localized prostate cancer using IMRT with a dose 78/82 Gy yielded an excellent 5-year tumour control with a risk of clinical relapse being less than 5%.

[Prostate bed radiotherapy--when and what?]. / Radioterapie luzka prostaty--kdy a co lécit?

BACKGROUNDS: Recently, prostate bed irradiation has, due to the results of randomized trials which confirmed its benefit in adjuvant treatment, become the standard treatment for patients with risk factors after radical prostatectomy. It is also irreplaceable in the treatment of biochemical progression caused by local recurrence. In most cases, the tumour is not visible on planning CT, so it is necessary to use all available information to define the target volume to treat all the sites where the recurrence could be present. DESIGN: The aim of this review is to provide a compendium of radiotherapy after radical prostatectomy, its indications and especially the localization of recurrences, which implicates the clinical target volume definitions. CONCLUSION: The treatment of prostate cancer requires close co-operation between urologists and radiation oncologists, especially now when the indication of radiotherapy includes patients with risk factors after radical prostatectomy where adjuvant treatment should be performed early after surgery. It is of the utmost importance to precisely define the target volume for radiotherapy to fully prevent local recurrence without unnecessary complications for the patient.

Time course of late rectal toxicity after radiation therapy for prostate cancer.

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=230) and 74 Gy for patients with locally advanced T3 tumors (n=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.

[Chronic gastrointestinal toxicity after external-beam radiation therapy for prostate cancer]. / Chronická gastrointestinální toxicita po zevní radioterapii karcinomu prostaty.

BACKGROUNDS: Chronic gastrointestinal (GI) toxicity is an important dose-limiting factor of prostate cancer treatment. Its incidence varies with the dose of radiotherapy and the external beam treatment technique; however, there are also other factors that should be considered. Despite all the efforts to diminish the incidence, chronic toxicity still remains an adverse event which can affect the quality of life in patients after prostate cancer radiotherapy. DESIGN: The aim of this review is to provide a detailed description of chronic GI toxicity after external beam radiation therapy for prostate cancer, its causes, development, symptoms and incidence in different treatment techniques, and to compare the development of GI toxicity from the beginning of curative prostate cancer radiotherapy to now. CONCLUSION: Thanks to up-to-date radiotherapy techniques, the incidence of chronic GI toxicity is relatively low despite high doses of about 80 Gy used in prostate cancer treatment. Further reduction of radiation complications could be achieved by using image-guided radiotherapy (IGRT), which enables more precise delivery of the radiation dose to the prostate, reduction of the margin around the clinical target volume (CTV) and the sparing of organs at risk.

High dose rate versus low dose rate brachytherapy in the treatment of tongue carcinoma - a radiobiological study.

UNLABELLED: Low dose rate (LDR) brachytherapy is a well established treatment for the early stages of tongue cancer. High dose rate (HDR) afterloading devices have replaced LDR brachytherapy in many radiotherapy departments, but the effect and safety of HDR brachytherapy in comparison with LDR brachytherapy for interstitial applications is an unresolved question. The aim of our radiobiological study was to utilize dose volume histiograms from patients treated in our institution to simulate the risk of complication of LDR and HDR brachytherapy. Normal tissue complication probabilities (NTCP) of acute mucositis, late mucosal necrosis and osteoradionecrosis of two HDR brachytherapy schedules (18 x 3 Gy bid and 10 x 6 Gy bid) and of LDR brachytherapy with identical tumor control probability were compared using data from 8 brachytherapy applications. A linear quadratic (LQ) model was used to calculate the biologically equivalent doses, the effective volume method of Kutcher and Burman and Lyman's model was used to calculate NTCP. The Student's two-tailed test was used for statistical analysis. For 18 x 3 Gy bid the risk of acute mucositis and of late mucosal necrosis was 1.48 and 1.66 times higher with HDR in comparison with LDR brachytherapy. For 10 x 6 Gy bid the risk of acute mucositis, mucosal necrosis and osteoradionecrosis was 1.3, 3.44 and 13.18 times higher with HDR brachytherapy. All differences were statistically highly significant. Our radiobiological study supported the hypothesis that HDR has a higher risk of complication in comparison with LDR brachytherapy for the same tumor control probability. KEYWORDS: tongue cancer, brachytherapy, low dose rate, high dose rate.