SABR in High-Risk Prostate Cancer: Outcomes From 2 Prospective Clinical Trials With and Without Elective Nodal Irradiation.
Int J Radiat Oncol Biol Phys
; 104(1): 36-41, 2019 05 01.
Article
em En
| MEDLINE
| ID: mdl-30445172
ABSTRACT
PURPOSE:
There is limited data on stereotactic ablative radiation therapy (SABR) in high-risk prostate cancer (PCa), especially regarding the role of elective nodal irradiation (ENI). This study compares 2 prospective phase 2 trials using SABR in high-risk PCa, with and without ENI. METHODS AND MATERIALS Patients had high-risk PCa. Those in trial 1 received 40 Gy in 5 fractions to the prostate and 30 Gy in 5 fractions to the seminal vesicles. Patients in trial 2 received 40 Gy in 5 fractions to the prostate and 25 Gy in 5 fractions to the pelvis and seminal vesicles. National Cancer Institute Common Terminology Criteria for Adverse Events toxicities were collected. Biochemical failure (BF) was defined as nadir + 2, and the 4-year prostate-specific antigen (PSA) response rate (4yPSARR) was <0.4 ng/mL.RESULTS:
Sixty patients were included (trial 1, n = 30; trial 2, n = 30). Median follow-up was 5.6 years and 4.0 years. The median nadir PSA was 0.02 ng/mL for both trials. Six patients had BF, all from trial 1. The BF rate was 14.6% at 5 years in trial 1 and 0% in trial 2. Sixty-three percent of patients in trial 1 and 93% in trial 2 had a 4yPSARR. Two patients died in trial 1, 1 from metastatic disease. One patient in trial 2 died of other causes. No other patients developed metastatic disease, and 1 patient in trial 1 had castrate resistant PCa. Overall survival at 5 years was 93.2% and 96.7% (P = .86). There was significantly worse late gastrointestinal and sexual toxicity in trial 1, but there was no difference in late genitourinary toxicity.CONCLUSIONS:
SABR in high-risk PCa yields biochemical control rates that may be comparable to that of other radiation therapy modalities. ENI using SABR is feasible and may lead to a significant improvement in biochemical control and in 4yPSARR, without an increase in late gastrointestinal or genitourinary toxicity. Longer follow-up would provide a better assessment of biochemical control. Well-conducted phase 3 trials are needed to fully establish the role of SABR and ENI in high-risk PCa.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Próstata
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Neoplasias da Próstata
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Glândulas Seminais
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Irradiação Linfática
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Radiocirurgia
Tipo de estudo:
Etiology_studies
/
Observational_studies
/
Prognostic_studies
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Risk_factors_studies
Limite:
Aged
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Aged80
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Int J Radiat Oncol Biol Phys
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Arábia Saudita