UCLA Journal of Radiation Oncology Fall and Winter 2022 - Flipbook - Page 34
UCLA RADIATION ONCOLOGY JOURNAL
SANDSTORM
Timing androgen-deprivation therapy with radiation therapy
improves outcomes in localized prostate cancer
BOTTOM LINE
This meta-analysis was designed to investigate
how the sequencing of ADT combined with RT
administered via prostate-only RT or whole-pelvis RT
might impact outcomes for prostate cancer patients.
Men with prostate cancer who are receiving
radiation often benefit from adding to the treatment
androgen deprivation therapy, a form of medication
that reduces testosterone. Historically, men have
been placed on androgen deprivation therapy
prior to beginning radiation. In a large analysis of
over 7,000 men treated internationally across 12
randomized trials, Dr. Kishan and colleagues have
shown that it is almost universally optimal for men
to begin androgen deprivation therapy when starting
radiation, so that most of the period of having a
low testosterone is "backloaded" after radiation is
complete.
FINDINGS
The analysis examined more than 7,400 patient
records, including 6,325 patients who had received
ADT before and during (neoadjuvant/concurrent)
their radiation therapy and 1,084 patients who
received ADT during and after (concurrent/adjuvant)
undergoing RT. The median follow-up period was
10.2 years.
Researchers observed a significant interaction
between ADT sequencing and RT field size for all
study endpoints except overall survival. For patients
receiving prostate-only RT, ADT occurring during
and after radiation was associated with improved
metastasis-free survival compared with neoadjuvant/
concurrent ADT.
BACKGROUND
Androgen-deprivation therapy (ADT), also called
hormone-suppression therapy, has consistently
been shown to improve survival rates when added
to radiation therapy (RT) for lower-risk patients with
localized prostate cancer. However, the optimal
sequencing of ADT for these patients remains
controversial. Two previous studies suggested that
ADT beginning with RT and continuing afterward
may be superior to the before-and-during RT
sequencing option, but both randomized trials
had limitations that made it difficult to infer broad
conclusions, according to the authors.
However, with patients receiving whole-pelvis
RT, no significant difference was observed with
ADT sequencing, except greater distant metastasis
occurrence among those who had concurrent/
adjuvant ADT. However, that finding should be
interpreted with caution due to details on how the
individual trials were structured.
Based on those trials, this study’s researchers
theorized that concurrent/adjuvant ADT sequencing
would offer improved metastasis-free survival
compared with neoadjuvant/ concurrent ADT
sequencing in patients receiving short-term (four
to six months) therapy in a RT field size-dependent
manner.
The study appears in the Journal of Clinical
Oncology.
CONCLUSION
The authors concluded that ADT sequencing
demonstrated a significant impact on clinical
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