A combined protocol with piroxicam, chemotherapy, and whole pelvic irradiation with simultaneous boost volumetric modulated arc radiotherapy for muscle-invasive canine urinary transitional cell carcinoma: First clinical experience

Abstract

The aims of this pilot study were to evaluate the feasibility and efficacy of high-dose hypofractionated volumetric modulated arc radiotherapy (VMAT) applied to whole pelvic region radiotherapy (WPRT) with multilevel simultaneous integrated boost (MLSIB) combined with piroxicam and chemotherapy for the treatment of canine transitional cell carcinoma (TCC) of the lower urinary tract with muscle invasion TCC. Twelve dogs were enrolled, according to stage, in two groups: group 1, TCC confined to the urinary tract; group 2, TCC with metastasis. The planning target volume dose was tailored from 36 to 42 Gy in 6 fractions. All dogs were prescribed piroxicam and radiosensitizing carboplatin, and six received chemotherapy after radiotherapy. Serial follow-ups with computed tomography and magnetic resonance imaging were performed. Disease control and toxicity effects were evaluated according to the Response Evaluation Criteria in Solid Tumors and Veterinary Radiation Therapy Oncology Group criteria. The treatment was well tolerated, and no high-grade side effects were reported. The median overall survival times for groups 1 and 2 were 1,230 and 150 days, respectively. A considerable percentage of patients in group1 (50%) were still alive at the time of writing this paper, and a longer follow-up could enable a more accurate survival analysis. This preliminary analysis shows that VMAT applied to the WPRT with MLSIB is an effective and safe option for dogs with lower urinary TCC, although the presence of metastases worsens the prognosis.

Molecular Markers in Urinary Bladder Cancer: Applications for Diagnosis, Prognosis and Therapy

“…One of the challenges is related to variations in size, position and shape of the bladder and surrounding structures throughout treatment, with surrounding normal tissues often being irradiated within the pelvic region. However, more recent protocols have shown improved tolerability, encouraging further studies [ 134 , 135 , 136 , 137 , 138 ]. The contribution of radiotherapy to antitumour activity in multimodal approaches requires better clarification, as well as its benefits compared to other therapies.…”

A Novel Surgical Hybrid Approach to Neoplastic Lesions in the Distal Part of the Urethra: A Pilot Series of Clinical Cases

“…The most common form of canine urinary tract cancer is transitional cell carcinoma (TCC), accounting for up to 2% of all malignancies of this species [ 1 ]. In the literature, urethral tumors are mainly described as transitional epithelial tumors, most often affecting bitches [ 2 , 3 , 4 ].…”

Case report laparoscopy-assisted pre-pubic urethrostomy as a palliative procedure for resection of distal urethral tumor in a female dog

“…Transitional cell carcinoma (TCC) is the most common form of canine urinary tract cancer, accounting for up to 2 % of all malignancies of this species [1]. Urethral tumors are mainly described in the literature as transitional epithelial tumors and affect thousands of dogs annually around the world [2][3][4][5].…”