the effects of dose escalation, and of short or long-term androgen suppression in subgroups of prostate cancer patients at the
population level, using a provincial cancer registry that was enhanced by a systematic chart review.
Materials/Methods: 7877 consecutive patients were diagnosed with prostate cancer in the Canadian province of Saskatchewan
from 1990 –2001, of whom 2,146 were treated with radical RT. All charts were reviewed to collect data on age, stage, Gleason
score (GS), PSA, use of androgen suppression (AS), dose per fraction (DPF) and total radiation dose (TD). Patients were
classiﬁed as low- (stage T1–2, GS 2– 6, PSAϽ10), intermediate- (stage T1–2, GS 7 and/or PSAϭ0 –20) or high-risk (stage
T3– 4 and/or GS 8 –10 and/or PSAϾ20). AS was categorized as none, Ͻ6 months and Ͼ6 months. DPF was divided into
quartiles as Ͻ/ϭ191, 192–200, 201–215, Ͼ215 cGy/fraction. Radiation doses were divided into quartiles as Ͻ/ϭ6500,
6501– 6600, 6601– 6842, Ͼ6842 cGy. Multivariate analyses were performed for each risk group, using the endpoint of 10-year
cause-speciﬁc survival (CSS).
Results: There were 707, 569 and 870 patients in the low-, intermediate- and high-risk groups respectively. In the low-risk
group, stage (T2 vs. T1: RRϭ2.540, pϭ0.037) had a signiﬁcant impact on CSS, while PSA was borderline (RRϭ1.129,
pϭ0.056), and other prognostic factors were not signiﬁcant.
In the intermediate-risk group, stage (T2 vs. T1: RRϭ3.285, pϭ0.012), grade (7 vs 2– 6: RRϭ1.833, pϭ0.042) and PSA
(RRϭ1.090, pϭ0.018) had a signiﬁcant impact on CSS, while other factors did not.
In the high-risk group, stage (T3– 4 vs. T1: RRϭ2.154, pϭ0.013), GS (7 vs. 2– 6: RRϭ2.051, p Ͻ0.001; 8 –10 vs. 2– 6:
RRϭ3.030, pϽ0.001), PSA (Ͼ40 vs. Ͻ 10:RRϭ2.013, pϭ0.002) and total radiation dose (6601– 6842 vs. Ͻ/ϭ6500, RR
ϭ0.626, pϽ0.020; Ͼ6842 vs. Ͻ/ϭ6500, RRϭ0.243, pϽ0.001) were all signiﬁcant, while hormone use and other factors were
Conclusions: In keeping with results from several clinical trials, RT treatment intensiﬁcation has a signiﬁcant impact on CSS
in men with high-risk prostate cancer. The effect of dose per fraction was not independently signiﬁcant in any risk groups. We
were not able to detect a beneﬁt from AS in low or intermediate risk disease, which may be at least partly due to less frequent
use of AS in these patients and/or lower event rates. In this study for high-risk groups, hormone use was usually correlated with
higher radiotherapy dose and hence did not show up as a signiﬁcant independent variable in the ﬁnal model.
Author Disclosure: K. Joseph, None; D. Skarsgard, None; R. Alvi, None; J. Tonita, None; C. Woitas, None; P. Tai, None.
The Treatment of Primary and Metastatic Renal Cell Carcinoma (RCC) With Stereotactic Body
Radiation Therapy (SBRT) and Stereotactic Radiosurgery (SRS)
, C. Bloch
, A. C. Paulino
, M. Galli Guevara
, S. Chiang
, S. Shen
, D. Baskin
, E. B. Butler
, R. Amato
Baylor College of Medicine, Houston, TX,
Methodist Hospital, Houston, TX
Purpose/Objective(s): RCC is often regarded as a radioresistant tumor. However, brain metastases from RCC have been
successfully treated with SRS. Therefore, metastases to extra-cranial sites may be treated with similar success using stereotactic
body radiation therapy (SBRT), where image-guidance allows for the delivery of precise high dose radiation in few fractions.
We report our experience with SRS/SBRT in the management of primary and metastatic RCC.
Materials/Methods: The image-guided Novalis radiation therapy system was used. Thirty patients with brain metastases were
treated with SRS (16 –22 Gy in a single fraction). Five of these patients underwent resection of their metastatic lesions after
SRS and their pathology was reviewed. Twenty patients with extra-cranial metastatic lesions (orbits, head and neck, lung,
mediatinum, sternum, clavicle, scapula, humerus, rib, spine, abdomen) and 2 patients with biopsy proven primary RCC (not
surgical candidates), were treated with SBRT (24 –32 Gy in 3– 4 fractions over 1–2 weeks). Immobilization using a body cast
and image-guidance was used for all patients with treated with SBRT. 4D-CT was utilized in the treatment planning to assess
Results: Overall local control rate was 96%. Of the 30 patients who received SRS to brain, follow-up MR images showed
decreasing or stable lesion size in 25 patients. 5 patients had an “increase in size” in their treated lesions, and underwent
resection of the lesions. Pathology revealed necrotic specimen without any viable RCC in each case. Of the 20 patients with
extra-cranial metastatic lesions, 18 patients achieved symptom relief after treatment; 2 patients had local progression. In the 2
patients with primary RCC, tumor size remained unchanged but their pain improved, and their renal function was unchanged
post SBRT. There was no signiﬁcant treatment related side-effect.
Conclusions: Precise high dose radiation can cause signiﬁcant tumor cell death in “radio-resistant” metastases from RCC. It
also offers excellent local control and symptom palliation, without signiﬁcant toxicity. Therefore, SBRT may represent a novel
non-invasive, nephron-sparing option for the treatment of primary RCC as well as extra-cranial metastatic RCC. A prospective
clinical trial using SBRT for primary and metastatic RCC is ongoing.
Author Disclosure: L. Doh, None; C. Bloch, None; A.C. Paulino, None; M. Galli Guevara, None; S. Chiang, None; S. Shen,
None; D. Baskin, None; E.B. Butler, None; R. Amato, None; B.S. Teh, None.
Long-Term T Cell Activation Following Combined In Situ Gene Therapy and Intensity-Modulated
Radiotherapy Compared to Gene Therapy as Mono-Therapy in Prostate Cancer Patients
, T. Satoh
, K. Tabata
, E. Aguilar-Cordova
, B. J. Miles
, D. Kadmon
, E. B. Butler
T. C. Thompson
Baylor College of Medicine, Houston, TX,
The Methodist Hospital, Houston, TX
Purpose/Objective(s): A program combining in situ gene therapy and intensity-modulated radiation therapy (IMRT) was
implemented for the treatment of prostate cancer because the complementary mechanisms of cytotoxicity may have an enhanced
S316 I. J. Radiation Oncology
Physics Volume 66, Number 3, Supplement, 2006