Merck Manual

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Selected Common Neoplasms that Can Be Treated with Radiation Therapy

Selected Common Neoplasms that Can Be Treated with Radiation Therapy

Tumor Type

Radiosensitivity

Comments

Nasal adenocarcinoma

Intermediate

Usually respond well but often recur

Nasal squamous cell carcinoma

Low

Response is often minimal

Nasal chondrosarcoma

Intermediate to high

Some subtypes respond better than others

Nasal osteosarcoma

Low

Response may be better if after surgery

Oral melanoma

Low to intermediate

Poor response usually unless after surgery

Oral squamous cell carcinoma

Low

Especially poor in cats; aggressive treatment required

Osteosarcoma

Low

Metastatic disease in >90%; pain palliation

Chondrosarcoma

Intermediate

Best when small; metastasis a problem

Fibrosarcoma

Low to intermediate

Depends on tissue of origin

Injection-related fibrosarcoma

Low to intermediate

Best if done after first surgery, poor later

Thyroid carcinoma

Intermediate to high

Usually respond very well; 131I possible

Thyroid adenoma

High

Treat with 131I (>95% cure)

Salivary adenocarcinoma

Intermediate

Usually respond well, especially in cats

Brain tumor – meningioma

Intermediate to high

Usually stabilizes mass; good clinical result

Brain tumor – glioma

Low to intermediate

Depends on size, location, and clinical signs

Brain tumor – lymphoma

High

Most effective treatment for CNS lymphoma

Brain tumor – metastasis

Intermediate

Effective but short term due to other disease

Spinal cord mesenchymal tumor

Intermediate

Reasonable response but dose limited by cord

Spinal neurofibrosarcoma

Low to intermediate

Short-term response good but commonly recur

Lymphosarcoma

High

Excellent response but can only treat locally

Cutaneous lymphoma

High

Often curative

Nasal lymphoma

High

Good response, often very durable

Thymoma

Low to high

Low for scirious form, high for lymphocytic

Mediastinal chemodectoma

Low

Large masses, dose limited by heart and lungs

Adrenal neoplasias

Low

Difficult to accurately localize treatment

Transitional cell carcinoma

Intermediate

May respond well initially but recur

Prostatic adenocarcinoma

Low to intermediate

Data available on response is quite variable

Mast cell tumors

Intermediate to high

Very good for low grade, less for high grade

Peripheral nerve sheath tumor

Intermediate to high

Strongly recommended after surgery

Soft-tissue sarcoma

Low to high

Improves control after surgery, not alone

Lick granuloma

Intermediate to high

Treatment of last resort, often works well

Transmissible venereal tumor

High

Very good control even for large tumors

Equine sarcoid

High

Used in refractory tumors, brachytherapy

Equine nasal carcinoma

Intermediate to high

Beam treatment effective, very few sites

Equine ocular squamous cell carcinoma

Intermediate to high

Best treatment when bone involved