Ultrasonic tissue characterization and histopathology in tumor xenografts following ultrasonically induced hyperthermia.

Cells derived from human skin malignant melanoma were implanted subcutaneously in athymic nude mice. Tumors which developed at the implant site were treated with ultrasonically induced hyperthermia at 49 degrees C for 30 min. Tumors were scanned with a computerized diagnostic ultrasound system before and after treatment. Light (LM) and electron (EM) micrographs of tumors were obtained after scanning. Changes in ultrasonic tissue characterization parameters following treatment were well correlated with histopathologic changes observed in tumors. The results are significant in terms of clinical application of ultrasonically induced hyperthermia for treatment of intraocular tumors and the noninvasive monitoring of tumors by use of diagnostic ultrasound.