Interstitial iodine-125 radiation without adjuvant therapy in the treatment of clinically localized prostate carcinoma

Abstract

William Cavanagh, B.S. 3 Posttherapy evaluation included clinical, biochemical (PSA), and pathologic (repeat needle biopsy) studies. No patient was surgically staged, and none received andro-1 Pacific Northwest Cancer Foundation/Northgen deprivation therapy. Morbidity was graded according to the Radiation Therapy west Hospital, Seattle, Washington.Oncology Group grading scale. Statistical appraisal was performed by the Kaplan-2 Department of Urology, University of WashMeier method. PSA failure was defined in two ways: (1) PSA progression, i.e., 2 ington, Seattle, Washington.consecutive increases from a nadir value; and (2) failure to attain an arbitrary serum PSA value of 1.0 or 0.5 ng/mL at last follow-up. 3 Department of Radiation Oncology, University RESULTS. The overall 7-year survival was 77%; there were no deaths from prostate of Washington, Seattle, Washington.carcinoma in this cohort. The 7-year actuarial PSA progression free outcome was 4 Northwest Tumor Institute, Seattle, Washing-89%, and the PSA°1.0 ng/mL outcome was 87%. When PSA°0.5 ng/mL was ton.selected as an outcome end point, and PSA values in this series of radiation-treated 5 Pathology Associates Inc., Spokane, Washingpatients were compared with PSA values proposed to indicate disease free survival ton.after radical prostatectomy (PSA°0.3-°0.6 ng/mL), the 7-year actuarial disease free survival was 79%. Morbidity was minimal except in patients who had preimplant or postimplant transurethral prostate resection. CONCLUSIONS.Outpatient-based iodine-125 prostate brachytherapy for prostate carcinoma classified as T1 or T2 resulted in biochemical outcomes comparable to end points resulting from radical prostatectomy and external beam radiation.

The radial distance of extraprostatic extension of prostate carcinoma

“…5,7,29 The often stated purpose of these criteria is to select for patients with a low probability of extraprostatic disease (including seminal vesicle invasion, lymph node metastases, and distant metastases), pu- bic arch interference, and postimplant obstructive symptoms. Patients with Gleason score Ͻ 7, PSA Ͻ 10, and prostate volume Ͻ 60 cc had maximum and mean radial EPE distances of 0.6 mm and 0.03 mm, respectively.…”

“…Although the published follow-up of patients treated with prostate brachytherapy is shorter than for other treatment modalities, relapse free survival rates appear comparable to EBRT or radical prostatectomy at 7 years. 6,7 The presence of EPE is important in determining acceptable treatment for localized adenocarcinoma of the prostate. We hypothesized that the technical approach to its treatment also depends on the radial extent of EPE perpendicular to the prostatic capsule, a concept that, to our knowledge, has not been studied previously.…”

“…This dose for a permanent iodine-125 (I-125) implant is typically 14,500 -16,000 centigrays (cGy) at the periphery of the target volume, which typically extends 3-5 mm beyond the edge of the prostate. 7 At the periphery of a prostate implanted with radioactive seeds, the dose gradient can be Ͼ2000 cGy/mm in the region of the dose falloff. 11 This steep dose gradient results from the sum of the dose profiles of each radioactive seed, which, individually, have a dose profile obeying the inverse square law, D ϰ 1/r 2 , where the dose, D, is proportional to 1/r 2 , and r 2 represents the square of distance from the source.…”

Treatment of recurrent gynecologic malignancies with iodine-125 permanent interstitial irradiation

“…Ragde and coworkers from the Pacific Northwest Cancer Foundation in Seattle have reported their experience with 126 consecutive patients treated with iodine-125 irradiation employing a Bruel & Kjaer ultrasound unit (31). The seminal vesicles were not included in the treatment plans and a Quimby (uniform loading) implantation technique was used.…”

Modern prostate brachytherapy

“…However, most importantly, the growing popularity of brachytherapy is a result of the encouraging reports of long term disease free survival (DFS). [2][3][4][5][6][7][8] Those reports demonstrated an equal or better outcome compared with more traditional treatments for many men with clinically localized prostate carcinoma.…”