Radiation therapy
for fibrosarcoma
in pets — Florida.

Surgery leaves cells behind.
Radiation eliminates them.

Fibrosarcomas are defined by their infiltrative growth pattern — microscopic tumor extensions reach well beyond what the surgeon can see or feel. This is why even an apparently complete resection is rarely truly complete, and why adjuvant radiation is not optional. It is the treatment that eliminates what surgery leaves behind.

In dogs, fibrosarcoma most frequently arises in the oral cavity — gingiva, hard palate, and maxilla — where the proximity to bone makes complete resection particularly challenging. Subcutaneous and extremity fibrosarcomas also occur. In cats, oral fibrosarcoma is less common than SCC, but injection-site fibrosarcoma (vaccine-associated sarcoma) is a well-recognized and highly aggressive entity treated with a specialized surgical + radiation approach.

Adjuvant vs. definitive radiation

Adjuvant CFRT — delivered after surgery — is the standard approach when resection is performed but margins are narrow or incomplete. This is the most common scenario for oral fibrosarcoma. Definitive CFRT is used as the primary treatment when surgery is not feasible due to tumor size, location, or the pet's overall health. Both achieve meaningful local control — adjuvant radiation produces the best outcomes when combined with surgical debulking.

CT is essential before any treatment decision

CT imaging defines the true extent of fibrosarcoma — bone involvement, vascular proximity, regional lymph node status, and the feasibility of surgical resection. This information directly shapes the radiation field and the treatment plan. Dr. DiBernardi reviews all imaging personally and coordinates with the surgical team when combined therapy is planned.