ORLANDO, Fla.—The time to prostate cancer (PCa) metastasis in treatment-naïve patients and after patientshave started androgen-deprivationtherapy is associated with overall survival(OS), according to the findings ofseparate studies presented at the 2015Genitourinary Cancers Symposium.
In a study of 92 PCa patients withmetastatic disease, Shusuke Akamatsu,MD, PhD, of the Vancouver ProstateCentre and Department of UrologicSciences at the University of BritishColumbia in Vancouver, and colleaguesfound that patients who have metastaticPCa at the time of their diagnosishave significantly shorter OS thanPCa patients who develop metastaseswhile their tumors are sensitive to castrationor after they become castrationresistant.
Of the 92 patients, 35 had metastasesat diagnosis (de novo-M), 26 developedmetastases while the cancer was stillcastration-sensitive (CSPC-M), and 31developed metastases after their cancerbecame castration-resistant (CRPC-M).The median time to death from diagnosiswas 12.3, 15.8, and 3.7 years in theCSPC-M, CRPC-M, and de novo-Mgroups, respectively.
The median timeto death from metastasis was 5, 2.6, and3.7 years, respectively, and the mediantime to death from CRPC was 2.7, 3,and 0.9 years, respectively.
The median time to metastasis in theCSPC-M and CRPC-M groups was 4.4and 11.4 years, respectively.
“Regardless of the timing of metastasis,”Dr. Akamatsu and colleaguesconcluded, “survival of more than 10years after initial diagnosis is possiblein cases that did not have metastasis atinitial presentation.”
In the other study, Loana Valenca,MD, of the Dana-Farber CancerInstitute, Harvard Medical School,Boston, and colleagues explored theassociation between time to PCametastasis and overall survival after thestart of androgen-deprivation therapy(ADT) in 415 PCa patients who experiencedbiochemical recurrence afterprimary local therapy but had non-metastaticdisease. The median follow-upwas 6.4 years.
Patients who had metastases identified1, 2, and 3 years after the start ofADT had a significant 7.6 times, 5.7times, and 5.8 times greater risk ofdeath, respectively, than patients whodid not have metastases at those timepoints.
The study also showed that the timeto metastasis from identification of castration-resistant disease is significantlyassociated with OS. Patients who hadmetastases identified 1, 2, and 3 yearsafter ADT initiation had a significant4.4, 4.6, and 5.2 times greater risk ofdeath, respectively, than patients whodid not have metastases identified atthose time points, according to theinvestigators.
Of the 415 patients in the study, 217(52%) underwent radical prostatectomywith or without radiation therapy and198 (48% underwent radiation therapyalone as their primary treatment.