Comparison of outcome endpoints in intermediate- and high-risk prostate cancer after combined-modality radiotherapy

Abstract

PURPOSE: To compare a standard radio-oncological and a surgical biochemical failure definition after combined-modality radiation therapy (CRT) in men with intermediate-and high-risk prostate cancer. METHODS: 425 men were treated with external beam radiotherapy (59.4 Gy, 33 fractions) and 125 J seed-brachytherapy (S-BT, 100 Gy). Biochemical recurrence (BR) was defined either as radio-oncologic (rBR), using a þ2 ng/mL prostate-specific antigen (PSA) increase above a nadir value, or as surgical (sBR), using a 2-year posttreatment PSA of $0.2 ng/mL. Biochemical recurrence-free, metastasis-free, cancer-specific, and overall survival were calculated at 5 and 10 years using the Kaplan-Meier method. Standard validation tests were used to compare both thresholds. RESULTS: After a median of 7 years, overall recurrence rates were 10.4% and 31.5% for rBR and sBR definitions, respectively. Both failure definitions proved sensitive for the prediction of metastases and cancer-specific death, whereas the rBR definition was significantly more specific. The accuracies of a correct prediction of metastases and death of prostate cancer were 73.1% vs. 96.2% and 72.2% vs. 92.9% for sBR vs. rBR, respectively. The inferior validity results of the sBR definition were attributable to a PSA-bounce phenomenon occurring in 56% of patients with sBR. Still, using the less suitable sBR definition, the results of CRT compared favorably to BRFS rates of surgical interventions. CONCLUSION: After CRT, the radio-oncological (aka Phoenix) failure definition is more reliable than a fixed surgical endpoint. Exclusively in high-risk patients, sBR offers a direct comparison across surgical and nonsurgical treatment options at 5 and 10 years.

Previous Malignancy as a Risk Factor for the Second Solid Cancer in a Cohort of Nuclear Workers

“…Increased "2 nd to 1 st " ratio for leukemia as a second cancer in this study supports the notion that leukemia can also be promoted by conditions related to cancer treatment process [12]. Regarding prostate cancer, this assumption is consistent with the latest studies on the risk assessment of prostate cancer after radiation therapy [13]. 51% of the first cancers followed by prostate cancer during the decade of follow-up study [14] that might suggest that this localization is more sensitive to the influence of factors associated with the presence of a previous cancer, including diagnostic and therapeutic exposure, what is the point of interest for further research.…”

Definitions of “Cure” After Low-Dose-Rate Brachytherapy in Low- and Intermediate-Risk Prostate Cancer: Phoenix or Surgical?

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“… 3 , 4 , 15 , 16 Intraoperative and 6 week–postoperative radiation doses were documented for quality control as proposed by Stock and Stone 15 and are reported elsewhere. 10 , 17 All involved institutions provided independent follow-up. Follow-up visits were appointed every 3 months for 2 years, every 6 months for another 2 years, and yearly thereafter.…”

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