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Hanna and Pimentel
296 Rev Assoc Med Bras 2017; 63(4):293-298
the whole sample. Actuarial rates of biochemical control
after 5 years were at 85% for patients with one prognostic
factor, 75% for two factors and 50% for three factors
(p=0.001). Global, cause-specific and disease-free sur-
vival rates were respectively at 92%, 98% and 68%. Com-
plication rates grade 3 or above totaled 8% for genitouri-
nary and 1% for rectal, with an impotence rate of 51% (B).
Is low dose-rate brachytherapy less toxic
than the other therapeutic options for
prostate cancer?
The expected toxicities for BT are suitably comparable to
the toxicity obtained with external beam RT. The expect-
ed toxicity pattern (rectal and urinary toxicity) differs
greatly from that observed with surgical options (infection,
abscess, lymphocele, surgical death), and therefore we do
not see a reason for analysis. The comparison of quality
of life will be approached in another question.
A multicenter US and Canadian randomized study15
comparing a surgical approach and BT analyzed toxicity
in 263 patients using standardized scores. At 5.2 years of
median follow-up, there were no differences in gastroin-
testinal and hormonal toxicity between the two groups.
However, the BT group had lower rates of urinary (91.8%
versus 88.1%, p=0.02) and sexual (52.5% versus 39.2%,
p=0.001) toxicity (A).
An Italian randomized study16 with 200 patients com-
pared toxicities between patients undergoing surgery or
LDR-BT. Urinary incontinence rates were 18.4% versus
zero, in favor of patients undergoing LDR-BT. The rates
of urethral stenosis were 6.5% versus 2%, also in favor of
BT, whereas the latter group presented 10% urinary reten-
tion at 12 months of follow-up versus zero in the surgery
group. Rectal toxicity was observed only in the BT group
(4%). Erectile dysfunction was assessed based on the In-
ternational Index of Erectile Function (IIEF) Questionnaire
and rates were similar between groups (62% versus 60%
of patients with preserved function). After 5 years of
follow-up, no toxicity rate was significantly different be-
tween the two groups (A).
An American retrospective population-based study
that included 60,134 patients from the SEER (Epidemiol-
ogy Department) database treated with BT (both mo-
dalities), external beam RT and BT (both modalities) plus
external beam RT, and 25,904 patients undergoing ob-
servation alone in order to examine the matter of genito-
urinary toxicity.28 The results showed that genitourinary
toxicity grades 2 to 4 accumulated in 10 years was 27.8%,
23.5% and 20.1% for BT plus external beam RT, BT alone,
and external beam RT alone, respectively, while patients
without active treatment had 19.9% of toxicity, which can
be considered as baseline level (C).
Two other retrospective series reported toxicity data
with sufficient follow-up time for comparison. A US study
analyzed patients treated with 81-Gy intensity-modulat-
ed radiotherapy (IMRT) and showed a similar rate to those
reported in BT studies (18% toxicity with a grade greater
than or equal to 2 in 10 years)29 (C) .
Another American study retrospectively analyzed
1903 consecutive patients undergoing three modern
techniques of RT – BT alone (HDR-BT or LDR-BT using
Pd-103), external beam RT plus image-guided radio-
therapy (IGRT), or the combination of both.30 Acute
grade 2 or greater urinary and intestinal toxicity was
lower in the group treated with BT alone. Late toxicity
was worse when the modalities were associated compared
to each one performed alone (C) .
Is high dose-rate brachytherapy less toxic
than the other therapeutic options for
prostate cancer?
A study cited in the previous question retrospectively
examined 1,903 patients undergoing three modern RT
techniques including HDR-BT or LDR-BT using Pd-103
and IGRT.26 The reported genitourinary toxicity rates
were 28%, 22% and 21% in patients submitted to BT plus
external beam RT, BT alone and external beam RT alone,
respectively. Patients kept on observation had 19.9% of
grade 2 or higher toxicity. In the same study, a lower rate
of rectal bleeding was demonstrated with BT alone com-
pared to the combination of external beam RT and BT,
or external beam RT alone, with respective rates at 0.9%,
7% and 16% (C).
Does low or high dose rate brachytherapy
affect quality of life less?
Although there is no consensus on how to evaluate the
various domains that impact quality of life after the var-
ious treatments of prostate cancer, there is a difference
in the results of each domain depending on the therapeu-
tic modalities.31
Three prospective studies directly compared quality of
life according to therapeutic modality, specifically LDR-BT
and surgery.
The first, Canadian, prospectively evaluated 190 pa-
tients undergoing radical prostatectomy or BT in a par-
tially randomized phase III design.15 The evaluations were
done with an instrument based on 50 items reported by
the patients (EPIC HRQOL). Questions regarding urinary
incontinence, urinary control and the degree of urinary