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HeLa S‐3 cells were treated with 195mPt‐radiolabeled cis‐diamminedichloroplatinum(II) (CDDP) under various conditions, and the relationship between lethal effect and the number of Pt atoms binding to DNA, RNA and proteins was examined. The mean lethal concentrations for the cells treated with CDDP at 37°C for 1, 2 and 3 h were 2.8, 2.0 and 1.1 μg/ml, respectively. By using identically treated cells, the number of Pt atoms combined with DNA, RNA and protein molecules were determined after fractionation of the cells using the method of Schneider. In this way, the Do values given as the drug concentration were substituted for the number of Pt atoms combined with each fraction, then the target volumes expressed as the reciprocals of Do values were calculated for each fraction. The results provide strong support for the idea that DNA is the primary target for cell killing by CDDP, and the target volumes were 5.17 × 104, 5.71 × 104 and 1.03 × 104 nucleotides for 1, 2 and 3 h treated cells, respectively.

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Focal or diffuse dilatation of pelvic vessels is observed occasionally on computed tomographic or magnetic resonance images. Two major mechanisms may account for dilatation. The first mechanism is development of collateral channels as a result of venous obstruction or stenosis. Symptoms associated with vessel dilatation vary according to the level of obstruction. Portal hypertension also may result in the formation of numerous collateral vessels. In addition, left renal venous compression between the aorta and the superior mesenteric artery, which results in blood flow from the left renal vein toward the left gonadal vein, causes a variety of symptoms. The second major mechanism for dilatation is increased blood flow through collateral vessels associated with a neoplasm or vascular lesion. Hypervascular pelvic tumors such as uterine leiomyomas, gestational trophoblastic neoplasms, ovarian solid tumors, and mesenteric tumors may be associated with a marked increase in the number of draining vessels. The assessment of such vessels can assist in identification of tumor origins. Visual recognition of abnormal pelvic vasculature and abnormal hemodynamics is clinically important because it helps to improve diagnosis of a wide variety of pelvic and systemic diseases. Moreover, recognition of abnormal hemodynamics facilitates understanding of the physiology of such conditions. Recognition of the pattern of collateral channels also assists in identification of the level of narrowing even when the level is not readily apparent and is dependent on postural position.

The thermometry results of radiofrequency (RF) capacitive hyperthermia for 60 deep-seated tumors in 59 patients are reported. Hyperthermia was administered regionally using two RF capacitive heating equipments which the authors have developed in cooperation with Yamamoto Vinyter Company Ltd., (Osaka, Japan). Intratumor temperatures were measured by thermocouples inserted through angiocatheters which were placed 5 cm to 12 cm deep into the tissues. Tumor center temperatures were measured for 307 treatments in all tumors; thermal distributions within tumors and surrounding normal tissues were obtained for 266 treatments of 53 tumors by microthermocouples. Thermometry results obtained were summarized as follows. A maximum tumor center temperature greater than 43 degrees C and 42 degrees C to 43 degrees C was obtained in 23 (38%) and 14 (23%) of the 60 tumors respectively. The time required to reach 43 degrees C in the tumor center was within 20 minutes after the start of hyperthermia in 87% of tumors heated to more than 43 degrees C. Temperature variations within a tumor exceeded 2 degrees C in 81% of tumors heated to more than 43 degrees C. The lowest tumor temperature greater than 42 degrees C was achieved in six of the 53 tumors (11%). Of 42 tumors in which temperatures of the subcutaneous fat, surrounding normal tissues, and the tumor center were compared, 24 (57%) showed the highest temperature in the tumor center and ten (24%) in the subcutaneous fat. When the heating efficacy was assessed in terms of a maximum tumor center, it great deal depended on the treatment site, tumor size, thickness of subcutaneous fat, and tumor type. Tumors in the head and neck, thorax, lower abdomen, and pelvis could be heated better than tumors in the upper abdomen. Greater heating efficacy was shown in patients with large, hypovascular tumors, and with the subcutaneous fat measuring less than 15 mm thick. The predominant limiting factor for power elevation was pain associated with heating. Systemic signs including increases in pulse rate and body temperature were not serious and seldom became limiting factors for power elevation. Our thermometry results indicate that the advantages of deep RF capacitive heating are its applicability to various anatomic sites and negligible systemic effects. The disadvantages are that its primary usefulness is limited to patients with thin subcutaneous fat and with large or hypovascular tumors.