RT Book, Section
A1 Rowe, Julie H.
A1 Gonzalez, Anneliese O.
A1 Jafri, Syed H.
A1 Cen, Putao
A1 Kanaan, Zeyad
A1 Amato, Robert J.
A1 Rios, Adan
A1 El-Osta, Hazem
A1 Mohlere, Virginia
SR Print(0)
ID 1162981135
T1 Basics of Oncology and Pathology
T2 Hematology-Oncology Clinical Questions
YR 2019
FD 2019
PB McGraw-Hill Education
PP New York, NY
SN 978-1-260-02662-7
LK hemonc.mhmedical.com/content.aspx?aid=1162981135
RD 2024/04/23
AB Table  Graphic  Jump  Location|Download  (.pdf)|PrintKey  conceptRadiation  therapy  techniques  have  evolved  for  more  than  a  century.  At  present,  the  majority  of  patients  are  treated  with  teletherapy  (ie,  external  radiation).  Teletherapy  treatment  modalities  include  electromagnetic  radiation  (ie,  X-rays  and  gamma  rays)  and  particulate  radiation  (electrons,  protons,  neutrons,  and  heavy  ions).  Brachytherapy  involves  implantation  of  radioactive  sources  into  the  tumor  tissues,  on  either  a  temporary  or  a  permanent  basis.  Dose  escalation  and  hypofractionation  can  benefit  patients  with  radiation-resistant  tumor  types,  including  sarcoma,  melanoma,  renal  cell  carcinoma,  and  colorectal  metastases.1Clinical  scenarioA  54-year-old  woman  is  diagnosed  with  inoperable  FIGO  stage  IIIB  squamous  cell  carcinoma  of  the  uterine  cervix  on  the  basis  of  pelvic  wall  involvement.  As  per  NCCN2  guidelines,  she  is  dispositioned  for  cisplatin-based  chemoradiation  with  curative  intent.Action  itemsRadiation  treatment  planning  and  delivery:  Optimal  radiation  therapy  for  cervical  carcinoma  involves  both  teletherapy  and  brachytherapy  components,  with  the  brachytherapy  component  being  essential  for  optimal  cure  rates,  as  this  modality  allows  for  dose  escalation  to  the  tumor  while  minimizing  the  dose  to  adjacent  healthy  structures1A  customized  treatment  plan  is  developed  that  includes  intensity-modulated  radiation  therapy  (IMRT)  to  the  pelvis  followed  by  multisession  intracavitary  brachytherapy  to  the  cervical  tumor1DiscussionOwing  to  advances  in  computational  delivery,  and  in  parallel  to  the  development  of  sophisticated  3-dimensional  volumetric  imaging  (including  CT,  PET,  and  MRI),  radiation  therapy  has  quickly  evolved  from  2-dimensional  treatment  planning  to  3-  and  4-dimensional  delivery  over  the  past  2  decades.1At  present,  dose  delivery  is  tailored  to  the  3-dimensional  volume  of  the  tumor.  The  most  sophisticated  techniques  use  inverse  planning  methods,  whereby  dose  delivery  is  optimized  through  computer-generated  fluence  maps.1  IMRT  remains  the  most  common  treatment  modality  for  advanced  teletherapy  delivery.  Particulate  delivery  with  protons  and  heavy  ions  is  also  being  evaluated,  with  physical  advantages  noted  for  certain  specific  applications  (including  pediatric  brain  tumors  and  chordomas  at  the  base  of  the  skull),  owing  to  specific  energy  deposition  differences  in  those  modalities.  The  use  of  proton  therapy  for  other  tumor  sites  is  under  investigation.1PearlsA  number  of  sophisticated  radiation  treatment  modalities  allow  for  increasing  treatment  options  for  treatment  of  multiple  disease  sites.ReferencesNational  Comprehensive  Cancer  Network  (NCCN)  guidelines.  Version  2.2017.  Available  at:  www.nccn.org.Halperin  EC,  Brady  LW,  Perez  CA,  et  al.  Perez  and  Brady’s  Principles  and  Practice  of  Radiation  Oncology.  6th  ed.  Philadelphia:  Lippincott  Williams  &  Wilkins;  2013.