Adjuvant radiotherapy following radical prostatectomy is more effective and less toxic than salvage radiotherapy for a rising prostate specific antigen

Abstract

SUMMARY Despite the trend toward earlier diagnosis of adenocarcinoma of the prostate, approximately 25% of men undergoing radical prostatectomy will have pathologic evidence of cancer extending outside of the prostate. These patients are at high risk for subsequent recurrence. Such relapses are almost always manifested initially as a rise in the Prostate Specific Antigen (PSA). Currently utilized PSA assays, however, will not detect a recurrence smaller than 10 7 to 10 8 cells, nor does PSA identify the site of recurrence. In contrast, the pathologic findings at the time of surgery can be used to reliably distinguish patients at risk for local recurrence from those more likely to fail distantly. Furthermore, adjuvant pelvic radiotherapy after prostatectomy, given to patients with an undetectable PSA who are at high risk for local recurrence, results in a higher disease free survival and fewer side effects than if radiotherapy is delayed until the PSA begins to rise. Thus, patients at high risk for local failure following radical prostatectomy, but at low risk for distant metastases (i.e., those with positive surgical margins and an undetectable PSA) should be offered immediate adjuvant radiotherapy.

Salvage Radiotherapy for Rising Prostate-Specific Antigen Levels After Radical Prostatectomy for Prostate Cancer: Dose–Response Analysis

“…Anscher (21) suggested that 1 cm 3 of prostate cancer volume would contain approximately 10 8 to 10 9 prostate cells. This number of cells should produce a serum PSA level of approximately 3.5 ng/mL.…”

510 Radiotherapy After Radical Prostatectomy: Treatment Recommendations Differ Between Urologists and Radiation Oncologists

“…Firstly, recurrences are predominantly local in the absence of seminal vesicle invasion or lymph node metastases, therefore early local treatment may prevent metastases [25]. Furthermore, because it is given for undetectable disease, adjuvant therapy may be effective at lower radiation doses than traditional salvage [26]. Indeed, although adjuvant radiotherapy is associated with increased complications compared to observation (23.8% vs. 11.9%), health related quality of life at 5 years was observed to be better for men in SWOG randomized to surgery plus radiotherapy compared to surgery alone [27,28].…”

O padrão 4 de Gleason e o volume tumoral no prognóstico do carcinoma da próstata

“…Mais recentemente, três estudos demonstraram que a porcentagem do padrão 4 de Gleason nos carcinomas Gleason 7 representa parâmetro importante na determinação da progressão da doença 14,16,17 . A literatura tem demonstrado maiores taxas de sobrevida livre de doença e menos efeitos colaterais em pacientes tratados com radioterapia adjuvante precocemente após a prostatectomia radical, quando os níveis de PSA são ainda indetectáveis 18,19,20 . O consenso do Canadian GU Radiation Oncologist Group propôs a separação de pacientes em três categorias pre-tratamento: baixo risco, risco intermediário e alto risco de progressão da doença, considerando-se o escore de Gleason, os níveis de PSA e o estádio tumoral 21 .…”