Introduction: Radiation therapy is a common modality used to treat residual and recurrent pituitary adenomas. Stereotactic radiosurgery (SRS) is frequently used with good control rates. Fractionated stereotactic radiotherapy (FSRT) recently has shown to be a viable alternative with similar outcomes to SRS. It is currently unknown whether radiation should be performed early for residual tumor, or delayed until recurrence occurs. We compare the role of FSRT in the treatment of residual versus recurrent disease.
Methods: A retrospective review of patients who underwent FSRT for nonfunctioning pituitary adenoma between January 2004 to November 2016 at Thomas Jefferson University was performed. A subgroup analysis was performed comparing the endocrinologic, ophthalmologic, and radiographic outcomes in residual versus recurrent pituitary adenoma.
Results: A total of 61 patients were analyzed, with mean follow-up of 48.1 months. Cavernous sinus involvement and optic apparatus abutment were present in 62.7% and 40.3% of patients. The median FSRT treatment dosage was 48.6 Gy over 28 fractions, with mean treatment volume of 11.2 mm3. All patients achieved radiographic control, with 15.1% attaining decrease in tumor size. The incidence of new endocrinopathy was 2.7%, and visual deficit was 1.4%.
FSRT for residual and recurrent disease occurred in 30 (mean time to treatment 8.1 months) and 31 (mean time to treatment 55.8 months) patients, respectively. The mean treatment volume was 6.8 versus 18.7 mm3. Treatment for recurrent disease resulted in two new endocrinopathies, whereas one case of visual deficit occurred in the treatment for residual disease.
Conclusions: FSRT is a durable treatment modality for the treatment of recurrent and residual pituitary macroadenomas. It results in excellent tumor control rates comparable to SRS with low risk of developing new endocrinopathies and visual deficits. Delayed treatment for recurrent tumor resulted in greater likelihood of endocrinopathy whereas early FSRT postoperatively for residual tumor may increase risk of visual compromise.
Patient Care: The results from our research can be beneficial in offering patients with residual and recurrent nonfunctional pituitary adenomas an effective and safe alternative treatment option, that is comparable to the current standard treatment.
Learning Objectives: 1. Recognize FSRT as an effective treatment option for residual and recurrent pituitary adenomas.
2. Compare the role of FSRT in the treatment of residual versus recurrent disease.
3. Understand potential complications that can result from FSRT