October - December 2008, Volume 4, Issue 4

Gheorghiu ML, Anghel R, Chicos P, Hortopan D, Dumitrascu A, Alexandrescu D, Coculescu M

Effect of postoperative radiotherapy on tumor growth of nonfunctioning pituitary adenomas

Acta Endo (Buc) 2008, 4 (4): 401-414
doi: 10.4183/aeb.2008.401

controversial. Aim. This study retrospectively reviews the tumor evolution in patients with NFA macroadenomas treated with surgery and conventional RT, as compared to surgery alone. Methods. Of 107 unselected patients with operated NFA (aged 19 - 77 years), evaluated between 1977 - 2008, 71 patients were follow-up without RT (group A), while 36 patients were submitted to RT (group B). Patients submitted to radiosurgery were not included. Both groups underwent serial imaging studies with computed tomography or magnetic resonance. Tumor evolution was conventionally defined as a change of minimum 25% of diameter. Results. The surgical approach was transfrontal in 47% of patients, transsphenoidal in 43% or both in 10% of patients, similar in both study groups. In group B, 30 patients underwent highvoltage RT (mean total dose 50.5 Gy) and 6 patients low-voltage RT (mean emission dose 16,775 R). Mean follow-up after surgery in group A was 3.4 years (range 6 months - 10 years) and after RT in group B it was 6.8 years (range 2 &#8211; 24 years), p < 0.001. In group A, 16 out of 71 patients had no visible tumor remnants. In this subgroup, 2 patients (12.5%) showed tumor recurrence. Fifty-five out of 71 patients had residual tumors, 21 with extrasellar extension after surgery. In this subgroup, 21 patients (38%) showed tumor re-growth and 7 (13%) showed tumor decrease. In group B (n=36) all patients had tumor remnants after surgery with extrasellar extension in 30 patients. After RT, tumor re-growth occurred in 5 out of 36 patients (14%) as compared to subgroup A with residual tumors (p< 0.05) and tumor decrease in 14 out of 34 (41%), as compared to the same subgroup A (p < 0.01). The 5 year-tumor re-growth free survival rate of 88% in irradiated patients was significantly better than in non-irradiated patients with residual tumors (31%, log-rank test, p < 0.01, Kaplan-Meier analysis), but similar to that in patients without remnants (87.5%). Age, sex, tumor parasellar extension and size of residual tumor were not predictors of recurrency. Conclusion. Postoperative radiotherapy provides a significant improvement of local control in patients with residual NFA compared to surgery alone. It is necessary a long term follow-up due to recurrency noticed up to 8 years postsurgery. In patients without tumor remnants, a wait-and-see policy is indicated after surgery.

Keywords: radiotherapy, non-functioning pituitary adenoma, pituitary surgery

Correspondence: Mihail Coculescu, MD, Endocrine Department, &#8220;Carol Davila&#8221; University of Medicine and Pharmacy, 34-36 Bd. Aviatorilor, 011863, Bucharest, Romania, e-mail: m.coculescu@uni-davila.ro