Reirradiation with stereotactic body radiation therapy after prior conventional fractionation radiation for locally recurrent pancreatic adenocarcinoma

Abstract

PurposeLocally recurrent pancreatic cancer after prior radiotherapy is a therapeutic challenge with limited treatment options. This study examines the safety and efficacy of stereotactic body radiation therapy (SBRT) for locally recurrent pancreatic adenocarcinoma after prior conventional fractionation radiotherapy (CRT).Methods and materialsOutcomes from all patients treated with SBRT for locally recurrent pancreatic adenocarcinoma after prior CRT at our institution were reviewed. A total of 23 patients were identified. Prior CRT median dose was 50.4 Gy (range, 30-60 Gy). Twelve patients (52%) had previously undergone surgery and received CRT as neo- or adjuvant treatment. Nine patients (39.1%) were reirradiated with SBRT with a dose of 25 Gy in a single fraction, and 14 patients (60.8%) received a 5-fraction SBRT schedule with a median dose of 25 Gy (range, 20-33 Gy) in 5 fractions (1-5 fractions).ResultsMedian follow-up time was 28 months (range, 9-77 months). The median planning target volume was 46 cm3 (range, 14-89 cm3). Median overall survival from diagnosis and from reirradiation were 27.5 months (range, 10-77 months) and 8.5 months (range, 1 month to not reached) respectively. The cumulative incidence of local failures at the last follow-up was 19%. For the 4 patients who presented with local failure, one was treated with a single fraction of 25 Gy, and the other 3 were treated with 25 Gy in 5 fractions. Three patients presented regional failure, with a cumulative incidence of 14%, all with concurrent distant progression. The cumulative incidence of distant progression was 64% at last follow-up. After reirradiation, 6 patients (26.1%) developed a grade 2 or 3 gastrointestinal toxicity, 4 of them occurring among patients treated with a single-fraction SBRT regimen.ConclusionsOur report shows that SBRT for reirradiation of locally recurrent pancreas adenocarcinoma is a feasible option with good local control and acceptable toxicity rates, especially with a multifraction schedule.

Stereotactic radiotherapy of pancreatic cancer: a systematic review on pain relief

“…Patients’ clinical stage was not reported in nine studies. 6 , 8 , 11 – 14 , 16 , 17 In one study, 100% of patients had cT4 tumor stage, 5 while in another trial, this rate was 87.5%. 10 In two studies only, patients with stage II–IV were enrolled 7 , 15 and in another, all patients had T1–3 N0 M0 PC.…”

“…From a total of 231 retrieved publications, after applying the selection criteria, 14 studies were found suitable for the analysis ( Figure 1 ). 4 – 17 …”

“…From a total of 469 patients, 190 patients reported with pain before SBRT treatment in 12 studies. 4 – 7 , 9 – 12 , 14 – 17 Two studies 8 , 13 did not report the number of patients with pain before SBRT.…”

“…Different treatment devices were used including robotic LINACs (six reports), 5 – 8 , 14 , 16 standard LINACs (five studies), 4 , 10 – 13 and both (three papers). 9 , 15 , 17 …”

“…Thirteen studies reported the details of PTV definition: eleven studies used a 1–5 mm GTV/internal tumor volume to PTV margin, 5 – 7 , 9 , 11 – 17 one study used a >10 mm GTV to PTV margin, 10 and only Hoyer et al defined the PTV as the GTV plus edema plus 5–10 mm. 4 …”