We report seven patients who underwent diagnostic laparoscopy and biopsy under local anesthesia using a new optical catheter. Six of these procedures were performed in the office. Four patients had previous malignancies (lung, breast, and fallopian tube), and intraperitoneal recurrences or new primaries were suspected. In two of these patients, laparoscopically directed biopsies confirmed adenocarcinoma similar to their prior malignancies, and in one a new primary was diagnosed. The fourth patient had no evidence of intraperitoneal disease. In the three patients with new intraperitoneal malignancies, biopsies obtained laparoscopically confirmed adenocarcinomas of the ovary in two patients and of the gastrointestinal tract in one patient. We feel that this procedure is a safe, simple, effective, and economical way to evaluate the intraperitoneal cavity and to obtain histologic or cytologic specimens for evaluation in patients with intraperitoneal malignancies. This is an ideal, minimally invasive method for detecting small-volume intraperitoneal disease. In addition, it allows some patients to be spared major operative procedures.