CT fusion

Abstracts / Brachytherapy 6 (2007) 77e118 PO-9 Surgery versus implant for early prostate cancer Roy H. Decker, M.D., Ph.D.1 Richard E. Peschel, M.D., Ph.D.1 Anwar Khan, M.D.1 Ann McKeon, B.S.1 John W. Colberg, M.D.2 1Therapeutic Radiology, Yale University School of Medicine, New Haven, CT; 2Urology, Yale University School of Medicine, New Haven, CT. Purpose: To compare the biochemical disease-free (bNED) survival rates for radical prostatectomy (RP) versus transperineal ultrasound guided implant (IMP) treated at a single institution from 1992 through 2005. Methods and Materials: The medical charts of 741 early prostate cancer patients (350 IMP and 391 RP) treated from 1992 through 2005 were retrospectively reviewed. The RP patients were treated by the academic Urology Section at Yale Medical School. For the 350 IMP patients, 35% were treated with iodine-125 and 65% with palladium-103, respectively. Ninety-two percent of the IMP patients were treated with IMP alone and 8% with combined external beam and IMP. Twenty-five percent of the IMP patients received short-term hormone therapy to downsize the prostate prior to IMP. Both IMP and RP patients were analyzed based on a favorable group (FG: clinical stage T1c or T2, PSA !10, Gleason score !7), intermediate group (IG: any one factor increased compared with FG), and a poor group (PG: any two factors increased compared with FG). The followup time varied from 12 months to 120 months with a mean followup of 44 months for IMP and 42 months for RP. PSA recurrence was defined as any detectable PSA following RP. PSA recurrence was defined as three successive rises in PSA following IMP. The bNED survival rates were calculated using the life-table method. Results: The 5-year bNED survival rates for IMP versus RP were not statistically significantly different for FG (92% vs 93%), IG (70% vs 70%), and PG (52% vs 50%). Conclusions: From 1992 through 2005, IMP therapy produced equivalent 5-year bNED survival rates compared with RP in early prostate cancer patients treated at a single institution. PO-10 Reduced toxicity with conformal image-guided brachytherapy (C-IGBT) vs. adaptive image-guided radiotherapy (A-IGRT) for favorable risk prostate cancer Sirisha R. Nandalur, M.D., Larry L. Kestin, M.D., Donald S. Brabbins, M.D., Michel I. Ghilezan, M.D., Gary S. Gustafson, M.D., Evelyn Sebastian, M.S., Di Yan, Ph.D., Frank A. Vicini, M.D., Alvaro A. Martinez, M.D. Radiation Oncology, William Beaumont Hospital, Royal Oak, MI. Purpose: To report our experience with morbidity in treating favorable risk prostate cancer with conformal IGBT versus adaptive external beam IGRT. Methods and Materials: 479 patients with favorable risk prostate cancer (PSA !10 ng/mL, Gleason <6, and clinical stage T1aeT2a) were treated with ultrasound-guided conformal interstitial brachytherapy (n 5 249) or CT-based offline adaptive IGRT (n 5 230) from 1992 to 2003. Low-doserate (LDR) permanent seed Pd-103 implants (120 Gy) was used in 171 of C-IGBT patients and high-dose-rate (HDR) implants via Ir-192 (38 Gy in 4 fractions) was used in 78 C-IGBT patients. A-IGRT patients were prospectively treated to a median dose of 75.6 Gy in 1.8-Gy fractions to the confidence limited-planning target volume (median isocenter dose 5 79.7 Gy). 141 patients (29%) also required short-term neoadjuvant androgen deprivation (AD) (38% C-IGBT vs. 20% for A-IGRT, p!0.01). Toxicity was quantified using the NCI Common Toxicity Criteria 2.0. Results: Median pretreatment PSA was 5.2 ng/mL for C-IGBT vs. 5.6 ng/ mL for A-IGRT. Median Gleason 5 6 and median stage 5 T1c in both groups. A-IGRT patients were older than C-IGBT patients (median age 5 73 vs. 66 years, p!0.01). Median followup was 4.6 years for C-IGBT vs. 3.7 years for A-IGRT. A-IGRT patients experienced significantly higher chronic grade > 2 gastrointestinal (GI) toxicity (16% vs. 1% for C-IGBT, p!0.01), especially rectal bleeding (11% vs. 0.4%, p!0.01). Chronic grade >2 genitourinary (GU) toxicity was 19% for A-IGRT vs. 25% for C-IGBT (p 5 0.09) with frequency/urgency as the most common toxicity in both groups. Chronic grade >3 toxicity was very low in both groups (GU: 4% A-IGRT vs. 6% C-IGBTdp 5 0.20,

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GI: 2% A-IGRT vs. 0.4% C-IGBTdp 5 0.11). Impotence was more likely with A-IGRT than C-IGBT (38% vs. 21%, p 5 0.01), although A-IGRT patients were older. Conclusions: Conformal IGBT patients experienced significantly less chronic grade 2 GI toxicity and impotence than those treated with adaptive IGRT. Very low chronic grade 3 toxicity was noted in either group.

PO-11 Erectile dysfunction following permanent prostate brachytherapy with dose escalation to biological tumor volumes (BTVs) identified with SPECT/CT fusion Rodney J. Ellis, M.D.1,2,3 Deborah A. Kaminsky, D.Ph.1 Hang Zhou, M.D.2 Martin I. Resnick, M.D.2 1Radiation Oncology, Aultman Hospital, Canton, OH; 2Urology, Case Western Reserve University School of Medicine, Cleveland, OH; 3Radiology, Northeastern Ohio Universities College of Medicine, Rootstown, OH. Purpose: Evaluate erectile dysfunction (ED) following brachytherapy with dose escalation to biological target volumes (BTV) identified by prostatespecific membrane antigen (PSMA) targeted 111Indium capromab pendetide (ProstaScint) single-photon emission tomography images co-registered with computed tomography (SPECT/CT). Methods and Materials: For the cohort, 70 hormone therapy naı¨ve and sexually active patients (median age 62 years, range 42e75) diagnosed with clinical T1ceT3a NxM0 prostate cancer underwent permanent prostate brachytherapy seed implant (SI) with dose escalation to SPECT/ CT identified BTV using Pd-103 or I-125 from 12/1999 through 12/2002. 42 patients underwent SI monotherapy, while 28 patients were treated with external beam radiation therapy plus SI boost (EBRT + SI). No ED was reported prior to treatment. Data was collected per ABS recommendations for the reporting of treatment related morbidity, using chart review and self-administered Sexual Health Inventory for Men (SHIM) forms. Median followup was 48 months (range: 24e72). ED definition is based on SHIM score <21. Results: ED rates for the whole group by SHIM score were 18.6% at one month, and 35.0%, 41.1%, 37.5%, and 43.2% at 1, 2, 3, and 4 years; for SI alone 14.6%, 20.0%, 47.1%, 39.4%, and 40.0%; and for EBRT + SI 25.0%, 50.0%, 30.0%, 36.4%, and 47.1%, respectively. Of the 55 patients who reported post-treatment ED by the SHIM score <21 definition, 24 (43.6%) reported use of sildenafil during the followup period. 15 (62.5%) reported ability to reach SHIM score O21 by using sildenafil (a complete response), 6 (25.0%) reported a partial response, and 3 (12.5%) reported no response. Additional post-treatment morbidities from our cohort included 14 patients having experienced a loss of sexual desire, 9 hematospermia, 7 orgasmalgia, 31 decreased intensity of orgasm, and 40 a decrease in volume of ejaculate. Conclusions: Analysis at 4 years median followup demonstrate that imageguided radiation therapy (IGRT) may be accomplished using the anti-PSMA monoclonal antibody ProstaScint with SPECT/CT fusion to define BTV for dose intensification, with maximal sparing of surrounding critical structures. This study demonstrates outcomes following dose escalation (150% of the prescribed dose) to BTV, with the majority of patients reporting post-treatment maintenance of adequate sexual function, per selfreporting recommendations defined by the American Brachytherapy Society for reporting treatment-related morbidity following brachytherapy. Dr. Ellis serves as PI on an unrestricted research grant funded by the Cytogen Corporation and participates in the Cytogen speakers bureau. This study includes uses of Capromab Pendetide (ProstaScint) outside its current indications.

PO-12 Comparison of post-implant dosimetry parameters for I-125 seed prostate brachytherapy determined using MR + CT images vs. CT images alone Ron Sloboda, Ph.D.1 Abe Alexander, M.D.2 John Pedersen, M.D.2 Albert Murtha, M.D.2 Don Yee, M.D.2 Nadeem Pervez, M.D.2 Brita Danielson, M.D.2 Marie Smerdely, M.D.3 1Medical Physics, Cross Cancer Institute,