Dose Tolerances

Question 1

Brainstem TD 5/5

Answer 1

50Gy to entire brainstem

60Gy to 1/3 brainstem

Question 2

Brainstem QUANTEC

Answer 2

Max <54 Gy, <5% chance of neuropathy or necrosis

Volume D1-10cc with dose/vol = 59 Gy, < 5% chance of neuropathy or necrosis

Question 3

Spinal Cord QUANTEC

Answer 3

Max does 50 Gy, 0.2% chance of myelopathy

Question 4

Chiasm and optic nerves QUANTEC

Answer 4

Max does less than 55 Gy, < 3% chance of optic neuropathy

Question 5

Retina dose constraints

Answer 5

Max does < 50 Gy, retinopathy (results in loss of vision)

Question 6

Cochlea dose constraints

Answer 6

Mean dose = 45Gy, hearing loss (Cisplatin-based chemo can enhance hearing loss)

Question 7

Bilateral Parotid gland dose constraints

Answer 7

Mean those = 25Gy, < 20% will have xerostomia (< 25% salivary function )

Question 8

Parotid gland (sparing one) dose constraints

Answer 8

Mean dose <20Gy, < 20% will have xerostomia (< 25% salivary function)

Question 9

Mandible dose constraints

Answer 9

Max point dose of =70Gy, osteoradionecrosis

Question 10

Pharyngeal constrictors dose constraints

Answer 10

Mean dose <50Gy, <20% chance of dysphagia & aspiration

Question 11

Larynx QUANTEC

Answer 11

Mean dose <44Gy, <20% chance of edema

Question 12

Brachial plexus TD 5/5

Answer 12

Max dose 60Gy has <5% risk of nerve damage after 5years

Question 13

Lung QUANTEC

Answer 13

V20 (=20Gy) to = 30% vol, <20% pneumonitis

Mean dose 20Gy, 20% chance of pneumonitis

Question 14

Esophagus QUANTEC

Answer 14

Mean dose < 34Gy, 5-20% chance of grade 3+ esophagitis

Question 15

Heart QUANTEC

Answer 15

Mean dose < 26Gy, <15% chance of pericarditis

Question 16

Heart: breast and Hodgkin’s lymphoma

Answer 16

V25 (=25Gy) to < 10% vol., <1% of cardiac mortality at 15 yrs after RT

Question 17

Liver QUANTEC

Answer 17

Mean dose <30 - 32Gy, <5% chance of RILD

Mean dose <42Gy, <50% chance of RILD

Question 18

Bilateral Kidney QUANTEC

Answer 18

Mean dose < 15-18Gy, <5% chance of Clinical dysfunction

Mean dose < 28Gy, <50% chance of Clinical dysfunction

V20 (=20Gy) to < 32% vol., <5% chance of Clinical dysfunction

Question 19

Stomach QUANTEC

Answer 19

D100cc receives < 45Gy, <7% chance of ulceration

Question 20

Small Bowel QUANTEC:

Individual loops and Peritoneal (Bowel Bag)

Answer 20

V15 (=15Gy) to < 120cc, <10% chance of grade 3+ toxicity

V45 (=45Gy) to < 195cc, <10% chance of grade 3+ toxicity

Question 21

Rectum QUANTEC

Answer 21

V50 (50Gy) to <50% vol, <10% chance of grade 3+ toxicity

V70 (70Gy) to <20% vol, <10% chance of grade 3+ toxicity

Question 22

Bladder QUANTEC

Answer 22

Max doe < 65Gy, <6% chance of grade 3+ toxicity

V70 (70Gy) to <35% vols, grade 3+ toxicity

Question 23

Penile bulb QUANTEC

Answer 23

Mean dose to 95% of gland <50%, <35% chance of Severe erectile dysfunction

Question 24

Femoral heads QUANTEC

Answer 24

Max dose < 50Gy, <5% necrosis or long-term hip replacement surgery

Question 25

Stereotactic Brain QUANTEC

Answer 25

Dose/Vol V12 (12Gy) to < 5-10cc

Question 26

Stereotactic brainstem QUANTEC

Answer 26

Max dose < 12.5 Gy

Question 27

Stereotactic optic chiasm/nerve QUANTEC

Answer 27

Max dose < 12Gy

Question 28

Stereotactic spinal cord (single fx) QUANTEC

Answer 28

Max dose 13Gy

Question 29

Stereotactic Liver (3 fractions) QUANTEC

Answer 29

Mean dose < 13Gy

Question 30

Brain Dose constraints

Answer 30

Max dose < 60Gy, <3% chance of symptomatic necrosis

Max dose 70Gy, 5% chance of symptomatic necrosis

Max dose 90Gy, 10% chance of symptomatic necrosis

Question 31

Stereotactic spinal cord (hypo fx) QUANTEC

Answer 31

Max dose 20Gy

Question 32

Stereotactic Cochlea QUANTEC

Answer 32

Rx dose, =14Gy