Radium-223 in metastatic castration-resistant prostate cancer: whole-body diffusion-weighted magnetic resonance imaging scanning to assess response.
JNCI Cancer Spectr
; 7(6)2023 Oct 31.
Article
em En
| MEDLINE
| ID: mdl-37788117
ABSTRACT
BACKGROUND:
Radium-223 is a bone-seeking, É-emitting radionuclide used to treat men with bone metastases from castration-resistant prostate cancer. Sclerotic bone lesions cannot be evaluated using Response Evaluation Criteria in Solid Tumors. Therefore, imaging response biomarkers are needed.METHODS:
We conducted a phase 2 randomized trial to assess disease response to radium-223. Men with metastatic castration-resistant prostate cancer and bone metastases were randomly allocated to 55 or 88 kBq/kg radium-223 every 4 weeks for 6 cycles. Whole-body diffusion-weighted magnetic resonance imaging (DWI) was performed at baseline, at cycles 2 and 4, and after treatment. The primary endpoint was defined as a 30% increase in global median apparent diffusion coefficient.RESULTS:
Disease response on DWI was seen in 14 of 36 evaluable patients (39%; 95% confidence interval = 23% to 56%), with marked interpatient and intrapatient heterogeneity of response. There was an association between prostate-specific antigen response and MRI response (odds ratio = 18.5, 95% confidence interval = 1.32 to 258, P = .013). Mean administered activity of radium-223 per cycle was not associated with global MRI response (P = .216) but was associated with DWI response using a 5-target-lesion evaluation (P = .007). In 26 of 36 (72%) patients, new bone metastases, not present at baseline, were seen on DWI scans during radium-223 treatment.CONCLUSIONS:
DWI is useful for assessment of disease response in bone. Response to radium-223 is heterogeneous, both between patients and between different metastases in the same patient. New bone metastases appear during radium-223 treatment.The REASURE trial is registered under ISRCTN17805587.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Neoplasias Ósseas
/
Rádio (Elemento)
/
Neoplasias de Próstata Resistentes à Castração
Tipo de estudo:
Clinical_trials
Limite:
Humans
/
Male
Idioma:
En
Revista:
JNCI Cancer Spectr
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Reino Unido