Carbon dioxide laser vaporization of diaphragmatic metastases for cytoreduction of ovarian epithelial cancer. Three patients with International Federation of Gynecology and Obstetrics state IIIC ovarian adenocarcinoma underwent CO2 laser vaporization of large-volume (5-6 cm) and miliary right hemidiaphragmatic metastases at the conclusion of standard debulking surgery to effect optimal cytoreduction. Destruction of diaphragmatic metastases was accomplished rapidly with no added morbidity or blood loss. The hand-held CO2 laser is a useful modality for removal of isolated large- and small-volume diaphragmatic disease, particularly if only the peritoneum is involved, and avoids the morbidity that may accompany entry into the pleural space. 