Stereotactically guided laser therapy of occult breast tumors - Work-in-progress report

Hypothesis: Mammographically detected breast tumors can be completely ablat ed with laser energy. Design: Nonrandomized control trial. Setting: A university hospital ambulatory care center. Patients: Thirty-six patients with mammographically detected well-defined b reast tumors were selected. Interventions: The diagnosis of malignant neoplasms and determination of pr ognostic factors were established by image-guided needle-core biopsy. Patie nts were treated on a stereotactic table, using a 16- to 18-gauge laser pro be, with an optic fiber transmitting a predetermined amount of laser energy . A multisensor thermal probe was inserted into the breast adjacent to the laser probe to monitor treatment. In the last 10 patients, the tumor blood flow was evaluated before and after laser therapy with contrast-enhanced co lor Doppler ultrasound. One to 8 weeks after laser therapy, the tumors were surgically removed and serially sectioned. Main Outcome Measure: Complete necrosis in 66% of tumors. Results: Total tumor ablation with negative margins was observed whenever 2 500 J/mL of tumor was given or the thermal sensors recorded 60 degreesC. Mi croscopic examination at 1 week showed disintegration of malignant cells, w ith peripheral acute inflammatory response and at 4 to 8 weeks extensive fi brosis. Contrast-enhanced color Doppler ultrasound revealed loss of tumor c irculation after therapy, and positron emission tomography scan correlated well with histologic findings. There were no systemic adverse effects. Two patients sustained 3 x 4-mm skin burns around the laser needle. Conclusion: A stereotactically guided minimally invasive technique may be e ffective for the treatment of mammographically detected breast cancer.