Purpose This study aimed to evaluate the efficacy of long-term neoadjuvant androgen-deprivation
therapy (ADT) before radical prostatectomy (RP). Methods We conducted meta-analyses
and network meta-analyses, which included randomized controlled trials that assessed
patients with prostate cancer (PC) who received either short-term (<6 months) or long-term
(>= 6 months) neoadjuvant ADT before RP. Results Thirteen articles with 2778 patients
were eligible for analysis. Short-term neoadjuvant ADT was neither associated with
biochemical recurrence (OR 1.19, 95% CI, 0.93-1.51, p = 0.17), metastasis (OR 0.73,
95% CI, 0.45-1.19, p = 0.21), nor overall mortality (OR 0.72, 95% CI 0.43-1.21, p
= 0.22); no study investigated survival outcomes in patients on long-term neoadjuvant
ADT. In terms of pathologic outcomes, long-term neoadjuvant ADT was significantly
associated with a reduced risk of positive surgical margin (SM) and an increased rate
of organ-confined disease (OCD) compared to short-term neoadjuvant ADT (OR 0.56, 95%
CI 0.39-0.80, p = 0.001, and OR 1.48, 95% CI 1.10-1.99, p = 0.009, respectively).
These findings were confirmed in the network meta-analyses. Meanwhile, only a non-significant
trend favoring long-term neoadjuvant ADT was observed for pathologic complete response
(OR 1.98, 95% Crl 1.00-3.93). Conclusion Long-term neoadjuvant ADT was associated
with more favorable pathologic outcomes, but whether these findings translate into
favorable survival outcomes still remains unproven due to very limited evidence. Since
there are no reliable survival data, long-term neoadjuvant ADT before RP should not
be used in clinical practice until more robust evidence arises from ongoing trials.
