Biomaterial Database

Local control following permanent prostate brachytherapy: effect of high biologically effective dose on biopsy results and oncologic outcomes. 2010

Nelson N Stone, and Richard G Stock, and Jamie A Cesaretti, and Pam Unger

Department of Urology, Mount Sinai School of Medicine, New York, New York, USA. nelsonstone@optonline.net

OBJECTIVE To determine factors that influence local control and systemic relapse in patients undergoing permanent prostate brachytherapy (PPB). METHODS A total of 584 patients receiving PPB alone or PPB with external beam radiation therapy (19.5%) agreed to undergo prostate biopsy (PB) at 2 years postimplantion and yearly if results were positive or if the prostate-specific antigen (PSA) level increased. Short-term hormone therapy was used with 280 (47.9%) patients. Radiation doses were converted to biologically effective doses (BED) (using alpha/beta = 2). Comparisons were made by chi-square analysis and linear regression. Survival was determined by the Kaplan-Meier method. RESULTS The median PSA concentration was 7.1 ng/ml, and the median follow-up period was 7.1 years. PB results were positive for 48/584 (8.2%) patients. Positive biopsy results by BED group were as follows: 22/121 (18.2%) patients received a BED of < or =150 Gy; 15/244 (6.1%) patients received >150 to 200 Gy; and 6/193 (3.1%; p < 0.001) patients received >200 Gy. Significant associations of positive PB results by risk group were low-risk group BED (p = 0.019), intermediate-risk group hormone therapy (p = 0.011) and BED (p = 0.040), and high-risk group BED (p = 0.004). Biochemical freedom from failure rate at 7 years was 82.7%. Biochemical freedom from failure rate by PB result was 84.7% for negative results vs. 59.2% for positive results (p < 0.001). Cox regression analysis revealed significant associations with BED (p = 0.038) and PB results (p = 0.002) in low-risk patients, with BED (p = 0.003) in intermediate-risk patients, and with Gleason score (p = 0.006), PSA level (p < 0.001), and PB result (p = 0.038) in high-risk patients. Fifty-three (9.1%) patients died, of which eight deaths were due to prostate cancer. Cause-specific survival was 99.2% for negative PB results vs. 87.6% for positive PB results (p < 0.001). CONCLUSIONS Higher radiation doses are required to achieve local control following PPB. A BED of >200 Gy with an alpha/beta ratio of 2 yields 96.9% local control rate. Failure to establish local control impacts survival.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009364	Neoplasm Recurrence, Local	The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.	Local Neoplasm Recurrence,Local Neoplasm Recurrences,Locoregional Neoplasm Recurrence,Neoplasm Recurrence, Locoregional,Neoplasm Recurrences, Local,Recurrence, Local Neoplasm,Recurrence, Locoregional Neoplasm,Recurrences, Local Neoplasm,Locoregional Neoplasm Recurrences,Neoplasm Recurrences, Locoregional,Recurrences, Locoregional Neoplasm
D011467	Prostate	A gland in males that surrounds the neck of the URINARY BLADDER and the URETHRA. It secretes a substance that liquefies coagulated semen. It is situated in the pelvic cavity behind the lower part of the PUBIC SYMPHYSIS, above the deep layer of the triangular ligament, and rests upon the RECTUM.	Prostates
D011471	Prostatic Neoplasms	Tumors or cancer of the PROSTATE.	Cancer of Prostate,Prostate Cancer,Cancer of the Prostate,Neoplasms, Prostate,Neoplasms, Prostatic,Prostate Neoplasms,Prostatic Cancer,Cancer, Prostate,Cancer, Prostatic,Cancers, Prostate,Cancers, Prostatic,Neoplasm, Prostate,Neoplasm, Prostatic,Prostate Cancers,Prostate Neoplasm,Prostatic Cancers,Prostatic Neoplasm
D012062	Relative Biological Effectiveness	The ratio of radiation dosages required to produce identical change based on a formula comparing other types of radiation with that of gamma or roentgen rays.	Biological Effectiveness, Relative,Effectiveness, Biologic Relative,Effectiveness, Biological Relative,Relative Biologic Effectiveness,Biologic Effectiveness, Relative,Biologic Relative Effectiveness,Biological Relative Effectiveness,Effectiveness, Relative Biologic,Effectiveness, Relative Biological,Relative Effectiveness, Biologic
D001918	Brachytherapy	A collective term for interstitial, intracavity, and surface radiotherapy. It uses small sealed or partly-sealed sources that may be placed on or near the body surface or within a natural body cavity or implanted directly into the tissues.	Curietherapy,Implant Radiotherapy,Plaque Therapy, Radioisotope,Radioisotope Brachytherapy,Radiotherapy, Interstitial,Radiotherapy, Intracavity,Radiotherapy, Surface,Brachytherapy, Radioisotope,Interstitial Radiotherapy,Intracavity Radiotherapy,Radioisotope Plaque Therapy,Radiotherapy, Implant,Surface Radiotherapy,Therapy, Radioisotope Plaque
D005500	Follow-Up Studies	Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.	Followup Studies,Follow Up Studies,Follow-Up Study,Followup Study,Studies, Follow-Up,Studies, Followup,Study, Follow-Up,Study, Followup
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001706	Biopsy	Removal and pathologic examination of specimens from the living body.	Biopsies
D016009	Chi-Square Distribution	A distribution in which a variable is distributed like the sum of the squares of any given independent random variable, each of which has a normal distribution with mean of zero and variance of one. The chi-square test is a statistical test based on comparison of a test statistic to a chi-square distribution. The oldest of these tests are used to detect whether two or more population distributions differ from one another.	Chi-Square Test,Chi Square Distribution,Chi Square Test,Chi-Square Distributions,Chi-Square Tests,Distribution, Chi-Square,Distributions, Chi-Square,Test, Chi-Square,Tests, Chi-Square