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Men with Intermediate Risk Prostate Cancer with a History of Transurethral Resection of Prostate (TURP) have a Higher Risk of Biochemical Failure
Proceedings of the 47th Annual ASTRO Meeting
Conclusions: Adjuvant therapy does not impact survival for patients after DP for cT4 CaP. However, since these patients have a median survival exceeding nine years despite extensive local involvement, adjuvant RT should be considered as an intervention to decrease likelihood of subsequent local failure. Supported in part by the Georgia Cancer Coalition, and NMCHD grant 5P60-MD000525.
* Mean (standard deviation) ** Median (interquartile range) *** Hazard ratio with follow-up truncated at five years
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Men with Intermediate Risk Prostate Cancer with a History of Transurethral Resection of Prostate (TURP) have a Higher Risk of Biochemical Failure
D.J. D’Ambrosio, M.K. Buyyounouski, E.M. Horwitz, S.J. Feigenberg, K. Ruth, A. Pollack Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA Purpose/Objective: Pretreatment prostate specific antigen (PSA) is a strong predictor of outcome following radiotherapy and is used to determine the appropriate radiotherapy dose and whether androgen deprivation therapy should be given. Because PSA is secreted from both normal and cancerous tissue, a prior recent transurethral resection of prostate (TURP) may lower pretreatment PSA levels out of proportion to the extent of disease. The purpose of this study was to determine if a history of TURP is associated with increased biochemical failure (BF) following radiotherapy for prostate cancer. Materials/Methods: From 4/89 to 10/01, 1,287 men with low to intermediate risk T1c-2NX/0M0 (2002 AJCC) prostate cancer with a pretreatment PSA ⬍ 20 ng/mL received 3D conformal radiotherapy (median dose: 76 Gy) without androgen deprivation therapy. The median pretreatment PSA was 7.3 ng/mL (range: 0.1–19.9). The proportion of men with PSA ⬎ 10 ng/mL was 362/1287 (28%) and Gleason 7 was 308/1287 (24%). There were 143 men with a prior history of TURP. The Cox proportional hazards model was used for univariate and multivariate analyses for BF (ASTRO definition). Results: For patients with pretreatment PSA 10 –19.9 ng/mL, prior TURP was an independent predictor of BF on univariate analysis (p⫽0.017) (See figure). For patients with a pretreatment PSA ⬍10 ng/mL, prior TURP was not a predictor of BF (p⫽0.232). Independent predictors of higher BF in the PSA 10 to 19.9 ng/ml subgroup including Gleason Score (2– 6 vs. 7), T-Stage (T1c vs. T2), PSA and age (both continuous) were prior TURP (p⫽0.0386) and radiation dose (p⬍0.0001). Conclusions: Transurethral resection of the prostate lowers the PSA mostly by reducing the proportion of normal prostate tissue. Our data indicate that those with an intermediate pretreatment PSA of 10 –19.9 ng/mL would have had a PSA ⬎20 ng/mL if a TURP was not done and would then have been considered high risk. A history of a TURP reduced the accuracy of PSA as a pretreatment determinant of BF for those with intermediate PSAs; therefore androgen deprivation should be considered in this setting.
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Conclusions: Adjuvant therapy does not impact survival for patients after DP for cT4 CaP. However, since these patients have a median survival exceeding nine years despite extensive local involvement, adjuvant RT should be considered as an intervention to decrease likelihood of subsequent local failure. Supported in part by the Georgia Cancer Coalition, and NMCHD grant 5P60-MD000525.
* Mean (standard deviation) ** Median (interquartile range) *** Hazard ratio with follow-up truncated at five years
2139
Men with Intermediate Risk Prostate Cancer with a History of Transurethral Resection of Prostate (TURP) have a Higher Risk of Biochemical Failure
D.J. D’Ambrosio, M.K. Buyyounouski, E.M. Horwitz, S.J. Feigenberg, K. Ruth, A. Pollack Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA Purpose/Objective: Pretreatment prostate specific antigen (PSA) is a strong predictor of outcome following radiotherapy and is used to determine the appropriate radiotherapy dose and whether androgen deprivation therapy should be given. Because PSA is secreted from both normal and cancerous tissue, a prior recent transurethral resection of prostate (TURP) may lower pretreatment PSA levels out of proportion to the extent of disease. The purpose of this study was to determine if a history of TURP is associated with increased biochemical failure (BF) following radiotherapy for prostate cancer. Materials/Methods: From 4/89 to 10/01, 1,287 men with low to intermediate risk T1c-2NX/0M0 (2002 AJCC) prostate cancer with a pretreatment PSA ⬍ 20 ng/mL received 3D conformal radiotherapy (median dose: 76 Gy) without androgen deprivation therapy. The median pretreatment PSA was 7.3 ng/mL (range: 0.1–19.9). The proportion of men with PSA ⬎ 10 ng/mL was 362/1287 (28%) and Gleason 7 was 308/1287 (24%). There were 143 men with a prior history of TURP. The Cox proportional hazards model was used for univariate and multivariate analyses for BF (ASTRO definition). Results: For patients with pretreatment PSA 10 –19.9 ng/mL, prior TURP was an independent predictor of BF on univariate analysis (p⫽0.017) (See figure). For patients with a pretreatment PSA ⬍10 ng/mL, prior TURP was not a predictor of BF (p⫽0.232). Independent predictors of higher BF in the PSA 10 to 19.9 ng/ml subgroup including Gleason Score (2– 6 vs. 7), T-Stage (T1c vs. T2), PSA and age (both continuous) were prior TURP (p⫽0.0386) and radiation dose (p⬍0.0001). Conclusions: Transurethral resection of the prostate lowers the PSA mostly by reducing the proportion of normal prostate tissue. Our data indicate that those with an intermediate pretreatment PSA of 10 –19.9 ng/mL would have had a PSA ⬎20 ng/mL if a TURP was not done and would then have been considered high risk. A history of a TURP reduced the accuracy of PSA as a pretreatment determinant of BF for those with intermediate PSAs; therefore androgen deprivation should be considered in this setting.
S311