Dose Constraints and Toxicity and other clinical things

Question 1

Head and Neck dose constraints (brain/CNS) 70Gy/35

Answer 1

Brain Dmax <60
Cord Dmax ≤ 48 (quantac 50Gy)
Brainstem Dmax ≤ 54
Chiasm Max dose ≤ 52
Lens Max Dose ≤25
Cochlea Max and mean dose < 45
Lacrimal Dmax <25 Gy unilateral

Question 2

Head and Neck dose constraints (other H&N) 70Gy/35

Answer 2

Mandible Dmax ≤ Rx dose
Esophagus: Mean dose < 34 Gy
Plexus: Max dose ≤63
Lips Max dose ≤ 30 Gy
Larynx Max dose < 50 Gy (vocal cord dysfx)

Question 3

H&N late toxicities (%)

Answer 3

Xerostomia (50% 6mo, 25% 1 yr, 15% 2 yr)

Peg tube dependency, dental problems, Chronic otitis media/hearing loss, trismus, neck fibrosis: all 10%

Brain necrosis, CN dysfunction (usually IX-XII), radiation myelitis, hypothalamic-pituitary or thyroid dysfunction: all <5% (thyroid as high as 15% if receiving >45 Gy)

Carotid stenosis

Question 4

HN acute toxicity

Answer 4

Mucositis
Skin erythema/desquamation
Odynophagia
Xerostomia
Taste alterations
Fatigue
Aspiration

Question 5

Radiation nephropathy :
1) what is the timeframe
2) most common clinical presentation
3) most common finding on urinalysis

Answer 5

1) 6-12 months
2) nephropathy: proteinuria, hypertension, impairment in urine concentration
3) proteinurea

Question 6

4 classes of drugs to deal with nausea

Answer 6

1) antihistamines
2) atypical antipsychotics (olanzapine)
3) zofran: serotonin antagonist
4) metaclopromide: prokinetic
5) corticosteroid (dex)

Question 7

1) hypercalcemia: symptoms
2) treatment

Answer 7

1) kidney stones, abdominal pain, psychiatric symptoms/confusion, weakness, polyuria, tachycardia
2) IV fluids, bisphosphonate, furosemide, calcitonin

Question 8

5 non-iatrogenic causes of kidney failure in MM

Answer 8

tubular damage from light chains

mets

hypercalcemia

recurrent infections

glomerular deposition of hyperuricemia and amyloid

Question 9

REMEMBER: is tumor more oxygenated pre-op with CRT vs post-op

Answer 9

Tumor oxygenation is enhanced with pre-op CRT!

Question 10

What is the rationale behind the following scenarios:
1) Chemo then PCI in leukemia
2) ABVD then consolidative RT
3) amifostine + RT in H&N
4) Cisplatin and EBRT in cervix

Answer 10

1) spatial cooperation
2) treatment consolidation (independent cell kill, non-overlapping toxicity)
3) Radioprotector (salvages free radicals) to decrease toxicity
4) radiation sensitization

Question 11

Treatment for Myasthenia gravis,
Lambert Eaton Syndrome

Answer 11

1) pyridostigmine
2) lambert eaton syndrome: treat with amifampridine

Question 12

Paraneoplastic syndromes: what is the most likely primary lung cancer:
1) hypertrophic osteoarthropathy
2) ectopic acromegaly

Answer 12

1) adenocarcinoma
2) large carcinoid tumor