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. (24th May 2016) - Fodor, Andrei
Abstract : 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.