Comparative effectiveness of low-dose-rate brachytherapy with or without external beam radiotherapy in favorable and unfavorable intermediate-risk prostate cancer

Abstract

We compared clinical outcomes associated with seed brachytherapy (SEED-BT) alone and SEED-BT plus external-beam radiotherapy (EBRT) for intermediate-risk prostate cancer using propensity score-matched analysis. From 2006 to 2011, 993 patients diagnosed with intermediate-risk were treated with either SEED-BT alone (n = 775) or SEED-BT plus EBRT (n = 158) at 3 tertiary hospitals. In the propensity score-matched analysis (102 pairs), median follow-up was 95 months (range 18–153 months). The 8-year biochemical recurrence-free rate (bRFR) was significantly better with SEED-BT alone than with combined radiotherapy (93.3% vs. 88.4%; HR 0.396; 95% CI 0.158–0.991). Grade 2 or greater late genitourinary toxicities were significantly fewer with SEED-BT alone than with combined radiotherapy (21.0% vs. 33.2%; HR 0.521; 95% CI 0.308–0.881). Similarly, grade 2 or greater late gastrointestinal toxicities were significantly fewer with SEED-BT alone (0% vs. 12.2%; HR 0.125; 95% CI 0.040–0.390). For the unfavorable intermediate-risk subgroups, SEED-BT alone yielded a significantly better bRFR than the combined radiotherapy (HR 0.325; 95% CI 0.115–0.915). SEED-BT alone might be a better disease-management plan than SEED-BT plus EBRT for intermediate-risk prostate cancer regardless of favorable and unfavorable characteristics.

Comparison of chronic gastrointestinal and genitourinary toxicities between brachytherapy and external beam radiotherapy for patients with prostate cancer: A systematic review and meta-analysis

“…The varied RT doses in studies must be considered when comparing the RRs of GI and GU toxicities between different therapies [ 31 ]. BT EBRT may increase the RRs of GI and GU toxicities because of the combined higher RT dose [ 32 , 33 , 34 ]. Increased urinary complications result from a high dose from EBRT during BT.…”

The effect of dose‐escalation radiotherapy with simultaneous‐integrated‐boost on the use of short‐term androgen deprivation therapy in patients with intermediate risk prostate cancer

“…8 Some trials have shown that RT alone is sufficient for FIR patients, but ADT is required for UIR patients receiving RT. 9 However, the use of ADT in IR-PC patients still remains debatable. 10,11 Modern irradiation techniques permit the administration of a higher radiation dose to intra-prostatic lesion (IPL) at each fraction in conjunction with whole prostate radiation therapy (RT)a technique known as the simultaneous integrated boost (SIB).…”

“…According to the current ‘National Comprehensive Cancer Network' (NCCN) guidelines, IR‐PC patients are divided into two groups: favorable (FIR) and unfavorable intermediate risk (UIR) 8 . Some trials have shown that RT alone is sufficient for FIR patients, but ADT is required for UIR patients receiving RT 9 . However, the use of ADT in IR‐PC patients still remains debatable 10,11 …”

Androgen deprivation therapy and radiotherapy in intermediate-risk prostate cancer: A systematic review and meta-analysis

“…The current National Comprehensive Cancer Network (NCCN) guidelines reclassify intermediate-risk PC patients into favorable intermediate risk (FIR) and unfavorable intermediate risk (UIR) (13). For FIR patients, some trials indicated RT alone is adequate but for UIR patients, ADT is warranted for patients receiving RT and considered for patients receiving RT with brachytherapy boost (14). However, the use of ADT in FIR patients is still controversial (15)(16)(17).…”