Complete response with early introduction of cabazitaxel in a patient with multiple lung metastases of castration-resistant prostate cancer following the early detection of metastases using liquid biopsy: a case report.BACKGROUND
 Cabazitaxel (CBZ) chemotherapy for metastatic castration-resistant prostate cancer (mCRPC) is believed to be palliative because the radiological response rate is low and a durable response is rare. 
Cabazitaxel
Complete response with early introduction of cabazitaxel in a patient with multiple lung metastases of castration-resistant prostate cancer following the early detection of metastases using liquid biopsy: a case report.BACKGROUND
 Thus, we performed liquid biopsy to isolate circulating tumor cells (CTCs), and overall 156 CTCs were detected per 7.5 mL.  The early detection of metastasis using liquid biopsy enabled the introduction of early CBZ chemotherapy for docetaxel-resistant mCRPC.
Liquid biopsy
Thus, we performed liquid biopsy to isolate circulating tumor cells (CTCs), and overall 156 CTCs were detected per 7.5 mL. 
Circulating tumor cells (CTCs)
Almost all CTCs were androgen receptor-negative in the nucleus. 
Androgen receptor-negative
We diagnosed the five nodules as lung metastases from docetaxel-resistant CRPC with few AR-signaling-dependent cancer cells. 
Docetaxel-resistant CRPC
The patient was initiated on CBZ chemotherapy (25 mg/m2) according to the standard protocol in August 2016, instead of using a second-generation AR-targeting agent. 
Second-generation AR-targeting agent