Radiation therapy for cats costs $1,500-$12,000. Radioiodine (I-131) at $1,500-$2,500 cures hyperthyroidism in ~95% of cases; fractionated radiation for cancer costs $3,000-$10,000+ over 15-20 anesthesia sessions. Radioiodine is the most common form - the only truly curative treatment for hyperthyroidism. Cancer radiation treats tumors that cannot be surgically removed.
(1) Radioiodine (I-131) - one-time injection, permanently cures hyperthyroidism in ~95%, 3-7 day hospitalization. (2) External beam - tumors (nasal, brain, FISS, oral) not fully removable; 15-20 daily anesthesia sessions. Radioiodine: truly curative in 95%
Radioiodine: single injection, no anesthesia; isolated 3-7 days; thyroid normalizes in 1-3 months. External beam: 15-30 minute fractions, 3-4 weeks under anesthesia; requires LINAC at specialty center. SRS/SRT: 1-5 high-dose fractions, more precise. External beam requires 15-20 anesthesia sessions
Radioiodine (I-131): $1,500-$2,500. External beam fractionated: $5,000-$10,000. SRS/SRT (1-5 fractions): $3,000-$8,000. Pre-radiation CT/MRI: $800-$2,500. Oncology consultation: $150-$300. Palliative: $1,500-$3,000.
After radioiodine: wear gloves 1-2 weeks; dispose of litter as low-level radioactive waste for 2 weeks; recheck at 1, 3 months. After cancer radiation: mucositis peaks 2-3 weeks, resolves 1-2 months; brain radiation may cause temporary neurological signs. Cats tolerate radiation better than most species
Radioiodine: $1,500-$2,500 all-in. Cancer radiation full course: $6,000-$12,000 including imaging and consultation.
Radioiodine: very low risk; hypothyroidism in ~2-5% post-treatment. Cancer radiation: anesthesia risk from repeated sessions; acute radiation side effects (mucositis, local skin reaction) expected but manageable.
Radioiodine: 3-7 day hospital stay. Cancer fractionated: 3-4 weeks of daily treatments. SRS/SRT: 1-5 sessions over 1-2 weeks. Full cure (radioiodine) confirmed at 3 months.
Radioiodine: licensed facilities exist in most major cities. Cancer LINAC radiation: veterinary oncology specialty centers and university hospitals only. University teaching hospitals often have the most competitive pricing.
02/04
Radioiodine for hyperthyroidism - the most common form of cat radiation therapy.
Radiation therapy is covered by most comprehensive policies when medically indicated. Radioiodine for hyperthyroidism is typically covered. Cancer radiation is covered when the underlying cancer is covered. At $1,500-$10,000, radiation is one of the highest-cost claims; annual benefit limit matters enormously.
Hyperthyroidism (the most common reason for radioiodine) is extremely common in older cats. Any pre-enrollment weight loss, elevated T4, appetite increase, or heart murmur from hyperthyroidism makes the condition pre-existing. All radioiodine costs denied. Enroll before age 8-10.
Cancer radiation ($6,000-$12,000) can exhaust low or mid-tier annual limits in a single claim. A $5,000 annual limit leaves $1,000-$7,000 uncovered. Policies with $10,000+ or unlimited annual benefits are essential if cancer radiation is a realistic need.
Some policies impose a 30-day cancer waiting period (vs 14 days for other illnesses). If any lump, mass, or suspicious finding was noted before the period expires, radiation claims may be denied as pre-existing. Especially relevant for recently adopted or newly enrolled cats.
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