Concomitant boost radiotherapy for muscle invasive bladder cancer
ABSTRACT To evaluate the feasibility and efficacy of a concomitant partial bladder boost schedule in radiotherapy for invasive bladder cancer, coupling a limited boost volume with shortening of the overall treatment time.
Between 1994 and 1999, 50 patients with a T2-T4 N0M0 transitional cell carcinoma of the bladder received radiotherapy delivered in a short overall treatment time with a concomitant boost technique. With this technique a dose of 40 Gy in 2-Gy fractions was administered to the small pelvis with a concomitant boost limited to the bladder tumor area plus margin of 15 Gy in fractions of 0.75 Gy. The total tumor dose was 55 Gy in 20 fractions in 4 weeks. Toxicity was scored according to EORTC/RTOG toxicity criteria.
The feasibility of the treatment was good. Severe acute toxicity >/=G3 was observed in seven patients (14%). Severe late toxicity >/=G3 was observed in six patients (13%). Thirty-seven patients (74%) showed a complete and five (10 %) a partial remission after treatment. The actuarial 3-year freedom of local progression was 55%.
In external radiotherapy for muscle invasive bladder cancer a concomitant boost technique coupling a partial bladder boost with shortening of the overall treatment time provides a high probability of local control with acceptable toxicity.
- SourceAvailable from: Tomasz Skóra
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- "Many studies have been conducted to improve the results of radiotherapy in treatment of invasive bladder cancer by adoption of altered fractionation, to reduce overall treatment time and acceleration of clonogenic repopulation of tumour [19–23]. One of the methods of altered fractionation, used in treatment of invasive bladder cancer, is accelerated superfractionated radiotherapy with concomitant boost, which allows to obtain a complete response in about 74–80% of invasive bladder carcinoma patients, with acceptable toxicity [19, 20]. "
ABSTRACT: To evaluate the toxicity, clinical effectiveness and survival rate of transurethral resection, neoadjuvant chemotherapy and accelerated hyperfractionated radiotherapy (concomitant boost), with or without concurrent cisplatin in patients with muscle invasive bladder cancer. Between March 2004 and December 2009, 35 patients with histologically proven invasive carcinoma of the bladder (T2-4a, N0-1, M0), who were fit for combined radiochemotherapy and refused radical surgery or were medically or surgically inoperable, were selected for the bladder-sparing protocol. In this study, twenty-five patients (25/35; 72%) received two cycles of neoadjuvant chemotherapy, and ten of them (10/35; 28%) only one, because of treatment-related toxicity. In twenty-one patients (21/35; 60%) chemotherapy consisting of gemcitabine with cisplatin and in fourteen patients (14/35; 40%) gemcitabine with carboplatin were applied. Only 13 patients (13/35; 37%) received combined irradiation with cisplatin. All patients completed their planned course of radiation therapy. Complete response (CR) occurred in 26/35 (74%) patients, partial response (PR) in 2/35(6%), and stable disease (SD) in 7/35 (20%). The overall actuarial survival rates at 3 and 5 years were 75% and 66%, respectively. Disease-specific actuarial survival rates at 3 and 5 years were 81% and 71%, respectively. Conservative treatment of patients with muscle-invasive bladder cancer by transurethral resection, neoadjuvant chemotherapy, and accelerated hyperfractionated radiotherapy with concomitant boost, with or without concurrent cisplatin, provides a high probability of local and distal response with acceptable toxicity in properly selected patients.Contemporary Oncology / Wspólczesna Onkologia 06/2013; 17(3):302-6. DOI:10.5114/wo.2013.35276 · 0.22 Impact Factor
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- "Conventional radiotherapy generally consists of irradiation of the entire bladder. However, when the tumor is unifocal, a focal tumor boost has been shown to provide a high local control rate with acceptable toxicity [1,2]. In focal bladder cancer irradiation, however, the large day-to-day variation of the tumor position causes a major problem [3-8]. "
ABSTRACT: The application of lipiodol injections as markers around bladder tumors combined with the use of CBCT for image guidance enables daily on-line position correction based on the position of the bladder tumor. However, this might introduce the risk of underdosing the pelvic lymph nodes. In this study several correction strategies were compared. For this study set-up errors and tumor displacements for ten complete treatments were generated; both were based on the data of 10 bladder cancer patients. Besides, two IMRT plans were made for 20 patients, one for the elective field and a boost plan for the tumor. For each patient 10 complete treatments were simulated. For each treatment the dose was calculated without position correction (option 1), correction on bony anatomy (option 2), on tumor only (option 3) and separately on bone for the elective field (option 4). For each method we analyzed the D99% for the tumor, bladder and lymph nodes and the V95% for the small intestines, rectum, healthy part of the bladder and femoral heads. CTV coverage was significantly lower with options 1 and 2. With option 3 the tumor coverage was not significantly different from the treatment plan. The DeltaD99% (D99%, option n - D99%, treatment plan) for option 4 was small, but significant. For the lymph nodes the results from option 1 differed not significantly from the treatment plan. The median DeltaD99% of the other options were small, but significant. DeltaD99% for PTVbladder was small for options 1, 2 and 4, but decreased up to -8.5 Gy when option 3 was applied. Option 4 is the only method where the difference with the treatment plan never exceeds 2 Gy. The V95% for the rectum, femoral heads and small intestines was small in the treatment plan and this remained so after applying the correction options, indicating that no additional hot spots occurred. Applying independent position correction on bone for the elective field and on tumor for the boost separately gives on average the best target coverage, without introducing additional hot spots in the healthy tissue.Radiation Oncology 06/2010; 5:53. DOI:10.1186/1748-717X-5-53 · 2.36 Impact Factor
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- "This plan was only generated for study purposes. The patients were actually treated with our current technique and a CTV-PTV margin [1,17]. "
ABSTRACT: The purpose of this study was to determine the dosimetric effect of on-line position correction for bladder tumor irradiation and to find methods to predict and handle this effect. For 25 patients with unifocal bladder cancer intensity modulated radiotherapy (IMRT) with 5 beams was planned. The requirement for each plan was that 99% of the target volume received 95% of the prescribed dose. Tumor displacements from -2.0 cm to 2.0 cm in each dimension were simulated, using 0.5 cm increments, resulting in 729 simulations per patient. We assumed that on-line correction for the tumor was applied perfectly. We determined the correlation between the change in D99% and the change in path length, which is defined here as the distance from the skin to the isocenter for each beam. In addition the margin needed to avoid underdosage was determined and the probability that an underdosage occurs in a real treatment was calculated. Adjustments for tumor displacement with perfect on-line position correction resulted in an altered dose distribution. The altered fraction dose to the target varied from 91.9% to 100.4% of the prescribed dose. The mean D99% (+/- SD) was 95.8% +/- 1.0%. There was a modest linear correlation between the difference in D99% and the change in path length of the beams after correction (R2 = 0.590). The median probability that a systematic underdosage occurs in a real treatment was 0.23% (range: 0-24.5%). A margin of 2 mm reduced that probability to < 0.001% in all patients. On-line position correction does result in an altered target coverage, due to changes in average path length after position correction. An extra margin can be added to prevent underdosage.Radiation Oncology 09/2009; 4:38. DOI:10.1186/1748-717X-4-38 · 2.36 Impact Factor