Monday, November 28 | 11:00 a.m.-11:10 a.m. | SSC16-04 | Room E352
The mechanics of focused ultrasound enhance the therapeutic effect of chemotherapy in patients with pancreatic cancer, South Korean researchers have found.A team led by Eun-Joo Park, PhD, of Seoul National University Hospital conducted an animal study to test the feasibility of combined treatment with focused ultrasound and chemotherapy for pancreatic cancer. In the first phase, immunodeficient mice were treated weekly for three weeks and then monitored for two weeks. The animals were divided into six groups: control, chemotherapy only, focused ultrasound at a low mechanical index, focused ultrasound at a high mechanical index, chemotherapy plus focused ultrasound at a low mechanical index, and chemotherapy plus focused ultrasound at a high mechanical index.
A second phase of the study included only two groups of animals treated in a four-week cycle that consisted of three weekly treatments and one week of monitoring. The two groups were chemotherapy only and chemotherapy plus focused ultrasound at a high mechanical index.
Park's team found that the tumor growth rate of animals treated only with focused ultrasound was lower than the rate of the control group, but higher than the group treated only with chemotherapy. Animals treated with both focused ultrasound and chemotherapy showed reduced tumor growth after two treatments. The tumor regrowth rate in the chemotherapy plus focused ultrasound at high mechanical index group was lower than in the group treated with chemotherapy alone.
The mechanical effects of focused ultrasound enhance the therapeutic effects of chemotherapy, Park and colleagues concluded, making the combination a possible new treatment protocol for pancreatic cancer.
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)