Referral

An 11 year old female miniature poodle presented for discussion of radiation therapy options for a left sided nasal mass ( suspect adenocarcinoma r/o sarcoma )

Patient History

The patient presented to her family veterinarian on 7/3/2018 for a 2-month history of epistaxis from the left nares. Bloodwork including a clotting profile was normal and she was referred to a regional referral hospital for further workup.

Diagnostics

A skull CT scan and rhinoscopy was done on 15/3/2018. A small contrast enhancing mass was noted in the left caudal nasal passage but was not visualised on rhinoscopy due to its caudal location. Blind biopsies were obtained and were not diagnostic. At the time she was started on tranexamic acid 125mg BID with intent to repeat imaging in 1 month. A follow up CT scan was done on 20/4/2018 which showed that the nasal mass had enlarged significantly. She was referred to the oncology team on 7/5/2018 to discuss radiation therapy for suspect nasal tumour. A surgical biopsy of the lesion was discussed but given the contrast uptake and notable enlargement of the lesion it was advised that the mass was likely neoplastic and regardless of type radiation therapy is the standard of care. It was decided to proceed with stereotactic radiotherapy.

Outcome

Treatment was tolerated very well with mild mucositis noted on the soft palate after treatment. This subsided within 1 week with no specific therapy. A follow up CT scan was done on 1/8/2018 which showed marked reduction in tumour volume.

Stereotactic radiation therapy (SRT) 3 day course of treatment to the left nasal mass

SRT was prescribed to the left caudal nasal mass. Treatment was delivered via volumetric arc therapy (VMAT)

285Gy in3# to the left nasal mass

VMAT fields are used to provide excellent treatment, preserving healthy tissue and critical surrounding structures

Treatment was planned using CT simulation

15 minute treatment time with daily image guided radiation therapy (IGRT) used to verify the accuracy and precision of treatment.