Radiation oncology

Radiation oncology is a place where people go after the pathologist has diagnosed it as cancer.

Dose

• Measured with several units.

Gray

• Abbreviated Gy.
• Energy/mass.

$1\ \mathrm {Gy} =1\ {\frac {\mathrm {J} }{\mathrm {kg} }}=1\ \mathrm {m} ^{2}\cdot \mathrm {s} ^{-2}$

Sievert

• Abbreviated Sv.
• "Biologic effect"/mass.

$Sv=X\cdot dose$

Where:

• X = fiddle factor for type of tissue and type of radiation.
• dose = dose in Gray.

Typical doses

Single dose:

• <0.5 Gy no histologic change.
• 1-2 Gy proliferating cells die.
• 10 Gy overt necrosis.

Total:

• Solid tumours ~ 60 to 80 Gy.
• Lymphoma ~ 20 to 40 Gy.

Biology

• DNA damage is thought to depend on reactive oxygen species.
  • Therefore, poorly oxygenated and poorly vascularized tissues are less sensitive to radiation exposures/treatments.

See also

• Oncology.
• Radiation colitis.
• Radiation changes.

External links

• Radiation oncology (wikibooks.org) - has substantial content and includes the AJCC staging.