Reassessment of the role of radiation therapy in the treatment of endocrine-inactive pituitary macroadenomas.
OBJECTIVE
This prospective clinical trial was undertaken to assess the rate of tumor recurrence in patients with endocrine-inactive pituitary macroadenomas who underwent gross total surgical resection of their tumors and did not receive adjuvant radiotherapy.


METHODS
Between December 1987 and July 1994, 45 patients with endocrine-inactive pituitary macroadenomas underwent transsphenoidal surgery. In 38 (84%) of these patients, gross total surgical resection was achieved and was confirmed by postoperative magnetic resonance imaging (n = 37) or computed tomography (n = 1). After receiving counseling from the neurosurgeon concerning the risks and benefits of radiation therapy, 32 of the 38 patients elected not to receive adjuvant radiotherapy. Patients were followed through March 1998 with radiographic imaging obtained every 6 months for the first 2 years, annually for postoperative Years 3 and 4, and then every 2 to 3 years thereafter. The study end point was defined as radiographic tumor recurrence or patient death.


RESULTS
The mean follow-up duration for the study group was 5.5 years. During that time, 2 of 32 (6%) patients developed recurrence, at 18 and 24 months, respectively, after initial surgery. Both were successfully treated using radiation therapy, with one requiring additional surgery. Three additional patients died as a result of unrelated causes 9, 12, and 49 months, respectively, after initial surgery. Immunocytochemical analysis revealed 66% of the tumors to be weak gonadotroph cell adenomas, 22% to be null cell adenomas, 9% to be silent prolactinomas, and 3% to be silent corticotroph cell adenomas.


CONCLUSIONS
This study demonstrates a 6% 5-year recurrence rate in patients with endocrine-inactive pituitary macroadenomas treated using gross total surgical resection alone. Reserving radiation therapy for the infrequent patient with recurrence and sparing the majority of patients the associated risks inherent in its use seems reasonable.
Lillehei
K O
KO
Department of Surgery, University of Colorado Health Sciences Center, Denver 80262, USA.
Kirschman
D L
DL
Kleinschmidt-DeMasters
B K
BK
Ridgway
E C
EC
D000236:Adenoma / Q000401:mortality / Q000503:physiopathology* / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D003131:Combined Modality Therapy; D004702:Endocrine Glands / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D010911:Pituitary Neoplasms / Q000401:mortality / Q000503:physiopathology* / Q000532:radiotherapy*; D011182:Postoperative Care; D011446:Prospective Studies