FOCALIZED EXTERNAL RADIOTHERAPY FOR RESECTED SOLITARY BRAIN METASTASIS - DOES THE DOGMA STAND

Purpose: To investigate whether whole brain irradiation might be repla ced by focalized irradiation after resection of a single brain metasta sis in patients where extracranial tumor control is deemed to be obtai ned. Patients and methods: Twelve patients were introduced in a phase I/II prospective study of conformal postoperative external irradiation after resection of a solitary brain metastasis. The radiation treatme nt consisted of 50.4 Gy (1.8 Gy per fraction, five fractions per week) . The planning target volume consisted of the tumor bed and a 2 cm saf ety margin. All treatments were optimized with head immobilization, de dicated tomodensitometry and computer assisted three-dimensional treat ment planning. Results: The median survival was 7.2 months (range 2.4- 50.4 months). Eleven of the 12 patients died. Eight of the 12 patients presented intracranial recurrence and seven died as a consequence of intracranial tumor progression. Conclusions: Focalized external irradi ation cannot serve as a reasonable alternative to whole brain radiothe rapy (WBRT) even for patients with apparently one single resected brai n metastasis. The dogma of 'one metastasis = multiple metastases' seem s to be confirmed. (C) 1998 Elsevier Science Ireland Ltd.