To achieve a differential diagnosis of cancerous disease in human soft tissues in vivo in organs such as the liver, breast etc., of cardiac dynamics with myocardial infarction etc. and hemodynamics or atherosclerosis etc., various strain measurement based shear modulus reconstruction methods have been developed. The strain tensor in a region of interest (ROI) is measured using ultrasound (US) or magnetic resonance (MR) imaging. The shear modulus reconstruction methods have also been applied to confirm the effectiveness of thermal treatments such as in human liver in vivo, e.g., regeneration, coagulation etc. In this study, the previously developed shear modulus reconstruction methods are extended, so that arbitrary internal mechanical sources expressed as a static or dynamic pressure, or as a force vector in a region of interest can be reconstructed together with a shear modulus such as a high intensity focused ultrasound (HIFU) and a radiation force for a tissue deformation as well as for treatments, static compressors, vibrators, heart motion and pulsation. Originally, the methods assumed that mechanical sources existed outside of a ROI (i.e., external sources). The new methods are also expected to be able to deal with an internal mechanical source combined with other unknowns, except for the shear modulus, e.g., inertia and mean normal stress. For the purpose of shear modulus reconstructions, such a decrease in the number of unknowns decrease computational time and increase the reconstruction accuracy and stability. The performed simulations show that the extended reconstruction methods have a high potential for yielding an arbitrary internal mechanical source reconstruction together with shear modulus reconstruction. The extension of the reconstruction methods will increase the applications of shear modulus reconstruction, e.g., a deeply situated tissue can be dealt with, and an image during a treatment with a HIFU or radiation force transmission also becomes possible. Moreover, the reconstruction of a mechanical source permits an evaluation of the activities of dynamic or static cells and tissues such as cardiac cells, blood vessels, skin, muscle, cells and tissues in culture etc. and the estimation of the point spread function (PSF) for designing an US beamformer, and for controlling HIFU treatment and tissue deformation (i.e. elasticity imaging) as well as for other applications.

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This paper describes the possibility of a new heating method with a needle applicator made of a shape memory alloy (SMA) to expand the heating area for interstitial brain tumor hyperthermia treatments. The purpose of the study described here is to show the capability of the method to expand a defined heating region with the developed three-dimensional (3-D) anatomical human head model using the finite element method (FEM). One major disadvantage of RF interstitial hyperthermia treatment is that this heating method has a small heating area. To overcome this problem, a new type of needle made of a SMA was developed. The specific absorption rate (SAR) distributions of this proposed method, when applied to the 3-D anatomical human head model reconstructed from two-dimensional (2-D) MRI and X-ray CT images, were calculated with computer simulations. The calculated SAR distributions showed no unexpected hot spots within the model. The heated area was localized around the tumor. These results suggest that the proposed heating method using the SMA needle applicator and the developed method for reconstructing a 3-D anatomical human head model are capable of being used for invasive brain tumor hyperthermia treatments.

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Attempts were made to administer chemotherapy (CT) and/or radiotherapy (RT) combined with hyperthermia (HT) to treat advanced lung cancer, although HT has rarely been used in lung cancer treatments.
This report examines the survival rate in 30 non-small-cell lung cancer (NSCLC) patients who were treated with CT combined with HT beginning with initial therapeutic efforts. The average patient age was 65.1 years old. There were 28 male patients, and 2 female patients. Twenty one patients were classified as having adenocarcinomas, and 9 patients were classified as having squamous cell carcinomas. Stage classification indicated 1 patient was stage IIB, 3 patients were stage IIIA, 11 patients were stage IIIB, and 15 patients were stage IV. The performance status of all patients was good (0-2). Systemic chemotherapy we used were paclitaxel plus carboplatin, camptothecine plus cisplatin (CDDP), mitomycin-C plus vinorelbin plus CDDP, gemcitabin plus CDDP, and TS-1 alone. All patients were administered this therapy safely.
The survival rate for 1-year survival of this therapy was 89.0%, the rate for 2-year survival was 64.5%, and the rate for 3-year survival was 32.5%. The median survival time was 27 months.
It was concluded that this combined therapy can improve the prognosis for NSCLC, and that this therapy can be recommended for additional patients.

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