152 / 1082
S139
ESTRO 36 2017
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= 3a, PSA > 20 ng/ml, GS > or = 8) prostate cancer who
underwent HDR brachytherapy as monotherapy (no
external beam radiotherapy) using 27 Gy/2 fractions in
one day from July 2011 to October 2014 were analyzed
prospectively. Patient age ranged 57 to 81 (median 72
）
years old. Fifty-nine patients were received neoadjuvant
hormonal therapy, and 10 patients were also adjuvant
hormonal therapy. Acute and late toxicities were assessed
as per Common Terminology Criteria for Adverse Events
(CTCAE), Version 4.03. The dosimetric factors affecting
the acute or late grade 2 to 3 GU toxicity were analyzed
by univariate analysis. PSA failure was defined as the
Phoenix definition of nadir + 2 ng/mL. Biochemical
relapse-free survival was analyzed using the Kaplan Meir
method.
Results
The median follow-up period was 52 months (range 21 –
64). The 4-year biochemical relapse-free survival rate was
89.0%. Neither acute nor late grade 2 to 3 rectal toxicities
developed. Acute grade 2 genitourinary (GU) toxicity
occurred in 12.0% (grade 3 in 0.0%).
The predictor of
acute grade 2 GU toxicity was urethra D90 (the dose that
covers 90% volume of the urethra) > 11.5 Gy (p-value <
0.01). Late grade 2 to 3 GU toxicity occurred in 20.5%
(grade 3 in 3.6%). However, any predictors of late grade 2
to 3 GU toxicity weren’t founded.
Conclusion
HDR brachytherapy as monotherapy in localized prostate
cancer is a highly effective treatment with minimal side
effects.
OC-0272 Long-term rectal toxicity following I-125
prostate brachytherapy in 1,260 patients
A. Yorozu
1
, S. Sutani
1
, R. Kota
1
, A. Sunaguchi
1
, K. Toya
1
,
S. Saito
2
1
Tokyo Medical Centre- NHO, Department of Radiation
Oncology, Tokyo, Japan
2
Tokyo Medical Centre- NHO, Department of Urology,
Tokyo, Japan
Purpose or Objective
To analyze factors associated with long-term rectal
toxicity in permanent prostate brachytherapy patients.
Material and Methods
This retrospective cohort study examined 1,260 patients
treated with I-125 brachytherapy without external beam
radiotherapy between 2003 and 2013. Neoadjuvant
androgen deprivation (NAD) was given to 39% of patients.
The patient, treatment, and dosimetry factors were
examined for an association with rectal toxicity. Toxicity
was graded according to the National Cancer Institute’s
Common Terminology Criteria for Adverse Events ver 4.0.
Rectal dosimetry was calculated through dose-volume
histogram of the rectum using day-1 and day-30 CT-based
dosimetry, and expressed as volume of rectum in cc
receiving 100% and 150% of the prescription dose (RV100
and RV150, respectively), and as dose to 5% and 30% of
rectum (RD5 and RD30 respectively). The Kaplan-Meier
method and Cox regression model were used for analysis.
Results
The median follow-up was 6.6 years. Median RV100 was
0.15 cc at day 1, and 0.56 cc at day 30. Any grade of
proctitis, rectal bleeding, fecal incontinence, diarrhea,
and anal pain was observed in 22.9%, 22.8%, 15.2%, 10.6%,
and 9.9% of patients, respectively. Toxicities were
categorized as grade 1 in 28.8% of patients and grade 2 in
1.7%. No Grade 3 toxicity was observed. Actuarial risk of
grade 2 rectal toxicity was 2.0%. The majority cases (82%)
of grade 2 toxicities were diagnosed by the third year.
Upon univariate analysis, the likelihood of G2 toxicity was
significantly associated with RV150, RV100, RD30, RD5 at
day 1, and NAD. Only RV100 at day 1 and NAD fit a Cox
regression model. Actuarial risk of grade 2 was 1.4%, 3.1%,
4.8%, and 6.7% for patients with RV100 <=0.2cc, 0.2-0.5cc,
0.5-1cc, >1cc at day 1, respectively (P=0.029). Actuarial
risk of grade 2 was 1.1 % for patients with NAD, and 2.2%
for patients without NAD (p=0.032).
Conclusion
I-125 prostate brachytherapy is well tolerated. Rectal
dosimetry at day 1 is relevant to long-term rectal toxicity.
RV100 and NAD are associated with rectal toxicity.
OC-0273 Prostate brachytherapy in African-Caribbean
patients: A retrospective analysis of 370 cases
V. Atallah
1
, N. Leduc
2
, M. Creoff
2
, P. Escarmant
2
, V.
Vinh-Hung
2
1
universitary hospital, radiotherapy, Pointe-a-pitre,
Guadeloupe
2
Universitary hospital Martinique, Radiotherapy, Fort-
de-france, Martinique
Purpose or Objective
Prostate cancer is the most frequent malignancy in
African-Caribbean men, a population sharing common
genetic traits with African-American (AA) but presenting
also genomic and epidemiologic specificities. Despite
socio-economic disparities with French mainland, all
patients were treated within the French state-financed
equal-access healthcare system. In this study, we report
biochemical outcomes of patients treated by
brachytherapy in our department from 2005 to 2014 in an
African-Caribbean population
Material and Methods
370 consecutive patients receiving I125 brachytherapy as
a curative treatment for early-stage (localized) disease
between 2005 and 2014 were recorded. Selected patients
presented with low risk disease: initial PSA (iPSA) < 10
ng/mL, clinical stage <= T2a, Gleason <7. Patients with
intermediate risk of recurrence were also included on a
case to case basis with PSA <15 or Gleason 7 (3+4).
Biochemical failure free-survival (BFFS) was defined
according to the ASTRO nadir+2 definition.
Results
The 3-year and 5-year BFFS for the entire cohort were
98.3% and 91.6% respectively. For patients with low and
intermediate-risk disease, the 5-year BBFS rates were 92.1
and 90.8%, respectively. In univariate and multivariate
analysis, only Gleason score (
˂
7 vs 7;
P
= 0.030
˂
0.05) was
a significant predictor of biochemical failure. The overall
rate of late and acute grade 2 or higher Genito-urinary
toxicity was 12.6% and 10.3 %.
Conclusion
In this large single-center series, brachytherapy achieved
excellent rates of medium-term biochemical control in
both low- and selected intermediate-risk localized
prostate cancer in African-caribean patients.
Brachytherapy seems to be an excellent choice of
treatment, with excellent outcomes and limited morbidity
for African-Caribbean populations. To our knowledge, our
series is the first presenting brachytherapy results in this
specific population.
OC-0274 Comparison of MRI/CT fusion and CT for
prostate post-implant dosimetry using sector analysis
N. Katayama
1
, M. Takemoto
2
, A. Takamoto
3
, S.
Sugiyama
1
, K. Hisazumi
1
, K. Watanabe
1
, H. Ihara
1
, K.
Katsui
1
, Y. Nasu
3
, S. Kanazawa
3
1
Okayama University Graduate School of Health Sciences,
Department of Radiology, Okayama, Japan
2
Himeji Red Cross Hospital, Department of Radiotherapy,
Himeji, Japan
3
Okayama University Graduate School of Health Sciences,
Department of Urology, Okayama, Japan
Purpose or Objective
Anatomical structures are well defined, so MRI/CT fusion
is considered the best method for postimplant dosimetry
of permanent prostate brachytherapy. We compared the
results obtained from MRI/CT fusion-based dosimetry with
those of CT-based dosimetry using sector analysis, and