Microdensitometry of T2-weighted magnetic resonance (MR) images from patients with advanced neoplasias in a phase I clinical trial of an infrared pulsed laser device (IPLD).

Background And Objective: The aim of this study was to determine whether an infrared pulsed laser device (IPLD)-induced pathophysiologic changes could be identified before measurable modifications in tumor volume.

Study Design/patients And Methods: Pre-and post-IPLD treatment magnetic resonance (MR) images of tumor heterogeneities and peritumoral tissues were digitized and a linear transformation was performed to convert images to 256 intensity levels. Data were analyzed by using the Student's t-test and the Kolmogorov-Sminov test (alpha = 0.05).

Results: The post-treatment mean intensity values of tumor heterogeneities increased significantly (P < 0.001) for all of the seven patients (n = 7) evaluated. For peritumoral tissues, a significant increase (P < 0.001) was measured in four patients (n = 4). The Kolmogorov-Sminov test showed significant values for the tumor tissue of six (n = 6) patients.

Conclusion: This is the first study of early evidence of anti-cancer activity of a novel IPLD showing a significant increase in the water content of tumor heterogeneities before measurable changes in tumor volume.