Toxicity and efficacy of salvage carbon 11-choline positron emission tomography/computed tomography-guided radiation therapy in patients with lymph node recurrence of prostate cancer
Menée auprès de 81 patients atteints d'un cancer de la prostate ayant récidivé avec une extension ganglionnaire, cette étude analyse les toxicités et l'efficacité, sur la survie sans progression et la survie globale à 3 ans, d'une radiothérapie hélicoïdale de sauvetage guidée par l'image (durée médiane de suivi : 36 mois)
Objective : To report the 3-year toxicity and outcomes of carbon 11 (11C)-choline-positron emission tomography (PET)/computed tomography (CT)-guided radiotherapy (RT), delivered via helical tomotherapy (HTT; Tomotherapy® Hi-Art II® Treatment System, Accuray Inc., Sunnyvale, CA, USA) after lymph node (LN) relapses in patients with prostate cancer. Patients and Methods : From January 2005 to March 2013, 81 patients with biochemical recurrence after surgery, with or without adjuvant/salvage RT or radical RT, and with evidence of LN 11C-choline-PET/CT pathological uptake, underwent HTT (median [range] prostate-specific antigen level 2.59 [0.61–187] ng/mL). Of the 81 patients, 72 were treated at the pelvic and/or lumbar-aortic LN chain with HTT at 51.8 Gy/28 fr and with simultaneous integrated boost to a median dose of 65.5 Gy on the pathological uptake sites detected by 11C-choline-PET/CT. Nine patients were treated without simultaneous integrated boost (50–65.5 Gy, 25–30 fr). Results With a median (range) follow-up of 36 (9–116) months, 91.4% of the patients had a PSA reduction 3 months after HTT. The 3-year overall, local relapse-free and clinical relapse-free survival rates were 80.0, 89.8 and 61.8%, respectively. The 3-year actuarial incidences of ≥grade 2 rectal and ≥grade 2 genitourinary toxicity were 6.6% (±2.9%) and 26.3% (±5.5%), respectively. A PSA nadir of ≥0.26 ng/mL (hazard ratio [HR] 3.6, 95% confidence interval [CI] 1.7–7.7; P = 0.001), extrapelvic 11C-choline-PET/CT-positive LN location (HR 2.4, 95% CI 0.9–6.4; P = 0.07), RT previous to HTT (HR 2.7; 95% CI 1.07–6.9, P = 0.04) and number of positive LNs (HR 1.13, 95% CI 1.04–1.22; P = 0.003) were the main predictors of clinical relapse after HTT. Conclusions 11C-choline-PET/CT-guided HTT is safe and effective in the treatment of LN relapses of prostate cancer in previously treated patients.