Subject(s)
Adenocarcinoma/veterinary , Cobalt Radioisotopes/therapeutic use , Eye Neoplasms/veterinary , Ferrets , Radioisotope Teletherapy/veterinary , Adenocarcinoma/radiotherapy , Adenocarcinoma/surgery , Animals , Combined Modality Therapy , Eye Neoplasms/radiotherapy , Eye Neoplasms/surgery , Male , Treatment OutcomeABSTRACT
Forty-five dogs with incompletely excised grade II mast cell tumors were treated with radiation using a cobalt 60 teletherapy unit (15 fractions of 3.2 Gy for a total of 48 Gy). Twenty-four of the dogs underwent prophylactic regional lymph node irradiation. Three (6.7%) dogs had tumor recurrence, two (4.4%) dogs developed metastasis, and 14 (31%) dogs developed a second cutaneous mast cell tumor. No difference in overall survival rate was observed between the dogs receiving and not receiving prophylactic irradiation of the regional lymph node.
Subject(s)
Cobalt Isotopes/therapeutic use , Dog Diseases/radiotherapy , Mastocytoma/veterinary , Radioisotope Teletherapy/veterinary , Animals , Cobalt Isotopes/toxicity , Dog Diseases/mortality , Dogs , Female , Kaplan-Meier Estimate , Lymph Nodes/radiation effects , Lymphatic Metastasis/prevention & control , Male , Mastocytoma/mortality , Mastocytoma/radiotherapy , Neoplasm Recurrence, Local/prevention & control , Neoplasm Recurrence, Local/veterinary , Retrospective Studies , Severity of Illness Index , Time Factors , Treatment OutcomeABSTRACT
Fifty-one cats and dogs with tumor recurrence after irradiation were treated with a second course of radiotherapy, using either teletherapy or brachytherapy. Eighty-six percent of the tumors had partial or complete response at 2 months after reirradiation. Tumor response was significantly (P = 0.041) affected when the interval between the 2 courses of irradiation was greater than 5 months. The estimated local tumor control rate was 38% at 1 year after reirradiation. Of all the factors examined, complete response at 2 months, reirradiation field size less than or equal to 10 cm2, and reirradiation dose greater than 40 gray emerged as predictors of local tumor control. The estimated overall survival rate was 47% at 2 years. Tumor location had a significant (P = 0.001) influence on overall survival; animals with cutaneous tumors had the longest survival times, and those with oral tumors had the shortest survival times. The other significant (P = 0.001) factor affecting overall survival time was the field size of the reirradiated site. Estimated survival time after reirradiation was 41% at 1 year. Favorable prognostic indicators were complete response at 2 months and location of tumor; animals with skin tumors had a favorable prognosis. The acute effects of reirradiation on normal tissues were acceptable, but 12% of the animals had severe delayed complications. Significant risk of complications after reirradiation was associated with squamous cell carcinoma (P = 0.015) and reirradiated field size greater than 30 cm2 (P = 0.056). When the interval between irradiations was greater than 5 months, the risk of complications was significantly (P = 0.022) lower.(ABSTRACT TRUNCATED AT 250 WORDS)
Subject(s)
Cat Diseases/radiotherapy , Dog Diseases/radiotherapy , Neoplasm Recurrence, Local/veterinary , Animals , Bone Neoplasms/radiotherapy , Bone Neoplasms/veterinary , Brachytherapy/veterinary , Carcinoma/radiotherapy , Carcinoma/veterinary , Carcinoma, Squamous Cell/radiotherapy , Carcinoma, Squamous Cell/veterinary , Cats , Dogs , Evaluation Studies as Topic , Female , Fibrosarcoma/radiotherapy , Fibrosarcoma/veterinary , Male , Mast-Cell Sarcoma/radiotherapy , Mast-Cell Sarcoma/veterinary , Mouth Neoplasms/radiotherapy , Mouth Neoplasms/veterinary , Neoplasm Recurrence, Local/radiotherapy , Nose Neoplasms/radiotherapy , Nose Neoplasms/veterinary , Radioisotope Teletherapy/veterinary , Skin Neoplasms/radiotherapy , Skin Neoplasms/veterinary , Soft Tissue Neoplasms/radiotherapy , Soft Tissue Neoplasms/veterinaryABSTRACT
Four dogs with metastatic seminoma were treated with cesium 137 teleradiotherapy. Minimum total tumor dose ranged from 17 to 40 gray (Gy) and was usually given through bilateral opposing sublumbar ports in eight to ten fractions, with three fractions given weekly. The tumor regressed in all four dogs. The first dog (case 1) was free of tumor and died of non-tumor related causes at 57 months. The second dog (case 2) was free of tumor but was euthanatized at 37 months for a limb fracture. The third dog (case 3) was euthanatized for undertermined pulmonary disease 43 months after radiotherapy. The fourth dog (case 4) was euthanatized 6 months following radiotherapy because of transitional cell carcinoma and renal failure. No evidence of seminoma was found at necropsy. Radiotherapy was shown to be effective treatment for seminoma with regional metastasis.
