OUTLINE: This is a dose escalation study. Patients receive gadolinium texaphyrin by IV infusion 20 minutes to 2 hours prior to magnetic resonance imaging and surgery. The maximum tolerated dose for a single dose of gadolinium texaphyrin is determined by cohorts of 3 patients who are treated at one of five escalating doses. Patients in each cohort are followed for a minimum of 4 weeks each before the next cohort begins. If good contrast enhancement is assessed at the fourth dose level (cohort 4), dose escalation stops. Patients are followed at days 1 and 2, at weeks 1, 2, and 4, and at 3 months after surgery.