Improving bladder cancer treatment with radiotherapy using separate intensity modulated radiotherapy plans for boost and elective fields

Phase I Clinical Trial of Everolimus Combined with Trimodality Therapy in Patients with Muscle-Invasive Bladder Cancer

Background: Local control following trimodality therapy (TMT) for muscle-invasive bladder cancer (MIBC) requires further optimization.

Objective: Evaluating the biologic endpoint, feasibility, and toxicity of integrating everolimus to TMT in patients with MIBC.

Methods: This was a phase I trial in patients with MIBC who were not surgical candidates or who refused cystectomy. Following maximal transurethral tumor resection, patients were treated by radiotherapy (50 Gy/20 fractions), gemcitabine (100 mg/m2/weekly) and escalating doses of everolimus (2.5–5.0 mg/day). Everolimus was given daily for one month prior to radiation, during treatment, and one month post-radiation. Toxicity assessment followed the Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring Criteria. Biologic endpoint with downregulation of phospho-S6 (pS6) was assessed using immunohistochemistry. Local response was evaluated with imaging and bladder biopsy post-therapy.

Results: 10 patients were recruited; 8 males, 2 females. Median age was 78 years (range: 63–85). Four patients entered everolimus 2.5 mg cohort. Six other patients entered everolimus 5.0 mg cohort. Toxicities were encountered in 2 patients (Grade I), 6 patients (Grade II), 9 patients (Grade III) and 1 patient (Grade IV), with some experiencing more than one toxicity. Most Grade III and IV toxicities were encountered from everolimus alone prior to combination testing. Trial was terminated early due to toxicity. Interestingly, 6/10 patients (60%) achieved a complete response with negative post-treatment biopsies. Significant decrease of pS6 was demonstrated post-therapy (p = 0.03).

Conclusions: Although combining everolimus with TMT achieved a biological endpoint and complete response in a significant number of patients with MIBC and negative prognostic factors, it was associated with unacceptable increased toxicity.

Clinical results of conformal versus intensity-modulated radiotherapy using a focal simultaneous boost for muscle-invasive bladder cancer in elderly or medically unfit patients

BACKGROUND

For elderly or medically unfit patients with muscle-invasive bladder cancer, cystectomy or chemotherapy are contraindicated. This leaves radical radiotherapy as the only treatment option. It was the aim of this study to retrospectively analyze the treatment outcome and associated toxicity of conformal versus intensity-modulated radiotherapy (IMRT) using a focal simultaneous tumor boost for muscle-invasive bladder cancer in patients not suitable for cystectomy.

METHODS

One hundred eighteen patients with T2-4 N0-1 M0 bladder cancer were analyzed retrospectively. Median age was 80 years. Treatment consisted of either a conformal box technique or IMRT and included a simultaneous boost to the tumor. To enable an accurate boost delivery, fiducial markers were placed around the tumor. Patients were treated with 40 Gy in 20 fractions to the elective treatment volumes, and a daily tumor boost up to 55-60 Gy.

RESULTS

Clinical complete response was seen in 87 % of patients. Three-year overall survival was 44 %, with a locoregional control rate of 73 % at 3 years. Toxicity was low, with late urinary and intestinal toxicity rates grade ≥ 2 of 14 and 5 %, respectively. The use of IMRT reduced late intestinal toxicity, whereas fiducial markers reduced acute urinary toxicity.

CONCLUSIONS

Radical radiotherapy using a focal boost is feasible and effective for elderly or unfit patients, with a 3-year locoregional control of 73 %. Toxicity rates were low, and were reduced by the use of IMRT and fiducial markers.

Promising results with image guided intensity modulated radiotherapy for muscle invasive bladder cancer

AIM

To describe the feasibility of image guided intensity modulated radiotherapy (IG-IMRT) using daily soft tissue matching in the treatment of bladder cancer.

METHODS

Twenty-eight patients with muscle-invasive carcinoma of the bladder were recruited to a protocol of definitive radiation using IMRT with accelerated hypofractionation with simultaneous integrated boost (SIB). Isotropic margins of .5 and 1 cm were used to generate the high risk and intermediate risk planning target volumes respectively. Cone beam CT (CBCT) was acquired daily and a soft tissue match was performed. Cystoscopy was scheduled 6 weeks post treatment.

RESULTS

The median age was 83 years (range 58-92). Twenty patients had stage II or III disease, and eight were stage IV. Gross disease received 66 Gy in 30 fractions in 11 patients (ten with concurrent chemotherapy) or 55 Gy in 20 fractions for those of poorer performance status or with palliative intent. All patients completed radiation treatment as planned. Three patients ceased chemotherapy early due to toxicity. Six patients (21 %) had acute Grade ≥ 2 genitourinary (GU) toxicity and six (21 %) had acute Grade ≥ 2 gastrointestinal (GI) toxicity. Five patients (18 %) developed Grade ≥2 late GU toxicity and no ≥2 late GI toxicity was observed. Nineteen patients underwent cystoscopy following radiation, with complete response (CR) in 16 cases (86 %), including all patients treated with chemoradiotherapy. Eight patients relapsed, four of which were local relapses. Of the patients with local recurrence, one underwent salvage cystectomy. For patients treated with definitive intent, freedom from locoregional recurrence (FFLR) and overall survival (OS) was 90 %/100 % for chemoradiotherapy versus 86 %/69 % for radiotherapy alone.

CONCLUSION

IG- IMRT using daily soft tissue matching is a feasible in the treatment of bladder cancer, enabling the delivery of accelerated synchronous integrated boost with good early local control outcomes and low toxicity.

[Concomitant chemoradiotherapy for muscle-invasive bladder cancer: current knowledge, controversies and future directions]

Radical cystectomy with lymphadenectomy is currently the standard of care for muscle-invasive urothelial bladder cancer; however and because of its morbidity and its impact on quality of life, there is a growing tendency for bladder-sparing strategies. Initially reserved for elderly or unfit patients unable to undergo radical cystectomy, chemoradiotherapy became a true alternative to surgery for highly selected patients. Although there are no randomized trials comparing radical cystectomy with bladder preserving approaches, surgery remains the preferred treatment for many clinicians. Furthermore, comparison is even more difficult as modalities of radiotherapy are not consensual and differ between centers with a variability of protocols, volume of irradiation and type of chemotherapy. Several ongoing trials are attempting to optimize chemoradiotherapy and limit its toxicity, especially through techniques of adaptive radiotherapy or targeted therapies.

Hypofractionated intensity modulated radiation therapy in combined modality treatment for bladder preservation in elderly patients with invasive bladder cancer

PURPOSE/OBJECTIVE(S)

To review our experience with bladder-preserving trimodality treatment (TMT) using hypofractionated intensity modulated radiation therapy (IMRT) for the treatment of elderly patients with muscle-invasive bladder cancer.

METHODS AND MATERIALS

Retrospective study of elderly patients treated with TMT using hypofractionated IMRT (50 Gy in 20 fractions) with concomitant weekly radiosensitizing chemotherapy. Eligibility criteria were as follows: age ≥70 years, a proven diagnosis of muscle-invasive transitional cell bladder carcinoma, stage T2-T3N0M0 disease, and receipt of TMT with curative intent. Response rate was assessed by cystoscopic evaluation and bladder biopsy.

RESULTS

24 patients with a median age of 79 years were eligible. A complete response was confirmed in 83% of the patients. Of the remaining patients, 1 of them underwent salvage cystectomy, and no disease was found in the bladder on histopathologic assessment. After a median follow-up time of 28 months, of the patients with a complete response, 2 patients had muscle-invasive recurrence, 1 experienced locoregional failure, and 3 experienced distant metastasis. The overall and cancer-specific survival rates at 3 years were 61% and 71%, respectively. Of the surviving patients, 75% have a disease-free and functioning bladder. All patients completed hypofractionated IMRT, and 19 patients tolerated all 4 cycles of chemotherapy. Acute grade 3 gastrointestinal or genitourinary toxicities occurred in only 4% of the patients, and acute grade 3 or 4 hematologic toxicities, liver toxicities, or both were experienced by 17% of the cohort. No patient experienced grade 4 gastrointestinal or genitourinary toxicity.

CONCLUSIONS

Hypofractionated IMRT with concurrent radiosensitizing chemotherapy appears to be an effective and well-tolerated curative treatment strategy in the elderly population and should be considered for patients who are not candidates for cystectomy or who wish to avoid cystectomy.

Intensity modulated radiotherapy for elderly bladder cancer patients

BACKGROUND

To review our experience and evaluate treatment planning using intensity-modulated radiotherapy (IMRT) and helical tomotherapy (HT) for the treatment of elderly patients with bladder cancer.

METHODS

From November 2006 through November 2009, we enrolled 19 elderly patients with histologically confirmed bladder cancer, 9 in the IMRT and 10 in the HT group. The patients received 64.8 Gy to the bladder with or without concurrent chemotherapy. Conventional 4-field "box" pelvic radiation therapy (2DRT) plans were generated for comparison.

RESULTS

The median patient age was 80 years old (range, 65-90 years old). The median survival was 21 months (5 to 26 months). The actuarial 2-year overall survival (OS) for the IMRT vs. the HT group was 26.3% vs .37.5%, respectively; the corresponding values for disease-free survival were 58.3% vs. 83.3%, respectively; for locoregional progression-free survival (LRPFS), the values were 87.5% vs. 83.3%, respectively; and for metastases-free survival, the values were 66.7% vs. 60.0%, respectively. The 2-year OS rates for T1, 2 vs. T3, 4 were 66.7% vs. 35.4%, respectively (p = 0.046). The 2-year OS rate was poor for those whose RT completion time greater than 8 weeks when compared with the RT completed within 8 wks (37.9% vs. 0%, p = 0.004).

CONCLUSION

IMRT and HT provide good LRPFS with tolerable toxicity for elderly patients with invasive bladder cancer. IMRT and HT dosimetry and organ sparing capability were superior to that of 2DRT, and HT provides better sparing ability than IMRT. The T category and the RT completion time influence OS rate.