A prospective evaluation of succinct prednisone tapering after brain tumor irradiation in dogs

Abstract

Background

To ameliorate anticipated or ongoing neurological deficits, dogs undergoing brain tumor irradiation often are prescribed lengthy courses of prednisone PO during and after radiotherapy (RT). This practice can contribute to unwanted corticosteroid-associated morbidity and may be unnecessary.

Objective

Determine whether long-term corticosteroid dependency can be minimized by use of succinct prednisone tapering.

Animals

Fifty-five pet dogs undergoing brain tumor irradiation.

Methods

Nineteen dogs were treated using a “rapid-taper” protocol wherein corticosteroid dose reduction began 0 to 20 days after completing RT. Outcomes were compared with a retrospectively studied control group (“slow-taper”; N = 36 dogs) in which corticosteroids were tapered more slowly according to individual clinician recommendations.

Results

Patient demographics were similar between groups. Mean time to lowest prednisone dose was 41 days postirradiation in the rapid-taper group and 117 days in the slow-taper group (P = .003). In the rapid-taper group, 15 of 19 dogs (84%) were completely tapered off prednisone, vs 18 of 36 (50%) in the slow-taper group (P = .04). Rates at which corticosteroids had to be reinstituted later were similar for the 2 groups (approximately 1 in 3 dogs). Adverse effect rates were similar for the 2 groups. Although no comparable questionnaire-derived data were available for the “slow-taper” group, overall and neurologic quality of life remained stable after RT in the rapid-taper group.

Conclusions and Clinical Importance

For many dogs, lengthy courses of PO prednisone are avoidable after intracranial RT. Future efforts should aim to identify which dogs benefit most from accelerated prednisone tapering.