PMID- 33392093 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20220419 IS - 2234-943X (Print) IS - 2234-943X (Electronic) IS - 2234-943X (Linking) VI - 10 DP - 2020 TI - Dosimetric Feasibility Study of Dose Escalated Stereotactic Body Radiation Therapy (SBRT) in Locally Advanced Pancreatic Cancer (LAPC) Patients: It Is Time to Raise the Bar. PG - 600940 LID - 10.3389/fonc.2020.600940 [doi] LID - 600940 AB - BACKGROUND AND OBJECTIVE: To assess the dosimetric feasibility of a stereotactic body radiotherapy (SBRT) dose escalated protocol, with a simultaneous integrated boost (SIB) and a simultaneous integrated protection (SIP) approach, in patients with locally advanced pancreatic cancer (LAPC). MATERIAL AND METHODS: Twenty LAPC lesions, previously treated with SBRT at our Institution, were re-planned. The original prescribed and administered dose was 50/30/25 Gy in five fractions to PTV(sib) (tumor-vessel interface [TVI])/PTV(t) (tumor volume)/PTV(sip) (overlap area between PTV(t) and planning organs at risk volume [PRV(oars)]), respectively. At re-planning, the prescribed dose was escalated up to 60/40/33 Gy in five fractions to PTV(sib)/PTV(t)/PTV(sip), respectively. All plans were performed using an inspiration breath hold (IBH) technique and generated with volumetric modulated arc therapy (VMAT). Well-established and accepted OAR dose constraints were used (D(0.5cc) < 33 Gy for luminal OARs and D(0.5cc) < 38 Gy for corresponding PRV(oars)). The primary end-point was to achieve a median dose equal to the prescription dose for the PTV(sib) with D(98)>/= 95% (95% of prescription dose is the minimum dose), and a coverage for PTV(t) and PTV(sip) of D(95)>/=95%, with minor deviations in OAR dose constraints in < 10% of the plans. RESULTS: PTV(sib) median (+/- SD) dose/D(95)/conformity index (CI) were 60.54 (+/- 0.85) Gy/58.96 (+/- 0.86) Gy/0.99 (+/- 0.01), respectively; whilst PTV(t) median (+/- SD) dose/D(95) were 44.51 (+/- 2.69) Gy/38.44 (+/- 0.82) Gy, and PTV(sip) median (+/- SD) dose/D(95) were 35.18 (+/- 1.42) Gy/33.01 (+/- 0.84) Gy, respectively. With regard to OARs, median (+/- SD) maximum dose (D(0.5cc)) to duodenum/stomach/bowel was 29.31 (+/- 5.72) Gy/25.29 (+/- 6.90) Gy/27.03 (+/- 5.67) Gy, respectively. A minor acceptable deviation was found for a single plan (bowel and duodenum D(0.5cc)=34.8 Gy). V38 < 0.5 cc was achieved for all PRV luminal OARs. CONCLUSIONS: In LAPC patients SBRT, with a SIB/SIP dose escalation approach up to 60/40/33 Gy in five fractions to PTV(sib)/PTV(t)/PTV(sip), respectively, is dosimetrically feasible with adequate PTVs coverage and respect for OAR dose constraints. CI - Copyright (c) 2020 Mazzarotto, Simoni, Guariglia, Rossi, Micera, De Robertis, Pierelli, Zivelonghi, Malleo, Paiella, Salvia, Cavedon, Milella and Bassi. FAU - Mazzarotto, Renzo AU - Mazzarotto R AD - Department of Radiation Oncology, University of Verona Hospital Trust, Verona, Italy. FAU - Simoni, Nicola AU - Simoni N AD - Department of Radiation Oncology, University of Verona Hospital Trust, Verona, Italy. FAU - Guariglia, Stefania AU - Guariglia S AD - Department of Medical Physics, University of Verona Hospital Trust, Verona, Italy. FAU - Rossi, Gabriella AU - Rossi G AD - Department of Radiation Oncology, University of Verona Hospital Trust, Verona, Italy. FAU - Micera, Renato AU - Micera R AD - Department of Radiation Oncology, University of Verona Hospital Trust, Verona, Italy. FAU - De Robertis, Riccardo AU - De Robertis R AD - Department of Radiology, University of Verona Hospital Trust, Verona, Italy. FAU - Pierelli, Alessio AU - Pierelli A AD - Department of Medical Physics, University of Verona Hospital Trust, Verona, Italy. FAU - Zivelonghi, Emanuele AU - Zivelonghi E AD - Department of Medical Physics, University of Verona Hospital Trust, Verona, Italy. FAU - Malleo, Giuseppe AU - Malleo G AD - Department of General and Pancreatic Surgery, University of Verona Hospital Trust, Verona, Italy. FAU - Paiella, Salvatore AU - Paiella S AD - Department of General and Pancreatic Surgery, University of Verona Hospital Trust, Verona, Italy. FAU - Salvia, Roberto AU - Salvia R AD - Department of General and Pancreatic Surgery, University of Verona Hospital Trust, Verona, Italy. FAU - Cavedon, Carlo AU - Cavedon C AD - Department of Medical Physics, University of Verona Hospital Trust, Verona, Italy. FAU - Milella, Michele AU - Milella M AD - Department of Oncology, University of Verona Hospital Trust, Verona, Italy. FAU - Bassi, Claudio AU - Bassi C AD - Department of General and Pancreatic Surgery, University of Verona Hospital Trust, Verona, Italy. LA - eng PT - Journal Article DEP - 20201217 PL - Switzerland TA - Front Oncol JT - Frontiers in oncology JID - 101568867 PMC - PMC7773844 OTO - NOTNLM OT - ablative dose OT - dose escalation OT - locally advanced OT - pancreatic cancer OT - stereotactic body radiotherapy COIS- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor declared a past co-authorship with several of the authors RM, NS. EDAT- 2021/01/05 06:00 MHDA- 2021/01/05 06:01 PMCR- 2020/01/01 CRDT- 2021/01/04 05:30 PHST- 2020/08/31 00:00 [received] PHST- 2020/11/17 00:00 [accepted] PHST- 2021/01/04 05:30 [entrez] PHST- 2021/01/05 06:00 [pubmed] PHST- 2021/01/05 06:01 [medline] PHST- 2020/01/01 00:00 [pmc-release] AID - 10.3389/fonc.2020.600940 [doi] PST - epublish SO - Front Oncol. 2020 Dec 17;10:600940. doi: 10.3389/fonc.2020.600940. eCollection 2020.