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H Nakajo

Publications and source records attributed to H Nakajo.

At least 19 recordsLinked to original sources
PubMed2001

[Assessment of left ventricular function with the solid-state digirad 2020tc Imager].

Multigated equilibrium radionuclide ventriculography from best septal position (LAO view) was performed in 17 patients with cardiac disease with a single detector Anger-type gamma camera (GCA 602A, Toshiba), then immediately imaged with a solid-state, multi-crystal gamma camera (Digirad 2020tc Imager). Acquisition times were the same of 10 minutes. The solid-state gamma camera uses CsI(Tl) as the scintillation material and a Si photodiode. CsI(Tl) has a higher density and higher atomic number than NaI(Tl), so that its efficiency for detecting gamma rays is higher. To confirm this, total acquisition counts in 17 patients obtained from the 2020tc Imager were significantly higher than those obtained from the Anger-type camera (7847 +/- 2061 K vs. 4427 +/- 1162 K counts, p < 0.0001). In comparing left ventricular ejection fractions obtained from the Anger-type camera and the 2020tc Imager data, an excellent correlation was revealed with a correlation coefficient of 0.97 (p < 0.0001). Again, peak ejection rate and peak filling rate obtained from the 2020tc Imager data correlated well with those obtained from the Anger-type camera data (r = 0.93, p < 0.0001 and r = 0.80, p < 0.001, respectively). These data reveal that the 2020tc Imager has an excellent data collection efficiency and a high reliability in assessment of left ventricular function. Thus, the solid-state gamma camera was thought to be a useful hardware in nuclear cardiology.

Aged↗
PubMed2001

[Examination concerning dissociation of left ventricular volume calculation value based on difference of analytical algorithm and perfusion tracer in gated myocardial SPECT].

According to improvement of SPECT system, ECG-gated SPECT with 201TlCl have been applied to the left ventricular volumetry. In this study 24 patients without ischemia demonstrated by stress (99mTc-TF) and rest (201TlCl) dual-isotope ECG-gated myocardial SPECT were enrolled. To evaluate left ventricular volumetry using 201Tl ECG-gated SPECT data, the left ventricular end diastolic volumes (EDV) were compared between Quantitative Gated SPECT (QGS) and Emory Cardiac Toolbox (ECT) as well as between dual-isotopes based on the same ECG-gated data. The EDV values with 99mTc data (EDVTc) using QGS were well correlated with those using ECT (r = 0.96, p < 0.0001). Both QGS and ECT demonstrated well correlation between EDVTc (r = 0.98, p < 0.0001) and the EDV value with 201Tl (EDVTl) (r = 0.93, p < 0.0001). However, QGS processing induced significantly lower EDVTl compared with EDVTc. In contrast, EDVTl were significantly higher than EDVTc in ECT performance. The QGS errors subtracting EDVTl from EDVTc were more evident according to the left ventricular volume increase. On the other hand, ECT error showed no tendency associated with the left ventricular volume. From these results, a careful strategy for selection of tracers and softwares should be necessary to assessment of quantitative values derived from ECG-gated SPECT data because of interaction with softwares, tracers, and subjects.

Adult↗
PubMed2000

Comparison of Emory and Cedars-Sinai methods for assessment of left ventricular function from gated myocardial perfusion SPECT in patients with a small heart.

To evaluate the effect of left ventricular (LV) size on the calculation of LV function from gated myocardial SPECT with Emory and Cedars-Sinai programs, we performed 99mTc-tetrofosmin gated SPECT on 49 patients with ischemic heart disease. End-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) were semi-automatically calculated by each program. All patients underwent left ventriculography (LVG) within 3 months before and after the SPECT study. We grouped the patients into 22 with a calculated ESV obtained from LVG of over 50 ml (group A) and 27 with an ESV value of 50 ml or below (group B). We then compared the ESV values from gated SPECT with those from LVG in each group. In group A, the ESV from both Emory and Cedars-Sinai programs similarly correlated well with those from LVG (r = 0.92 and r = 0.93, respectively), but in group B, the ESV calculated from the Cedars-Sinai program correlated less with those from LVG (r = 0.53) than those from the Emory program did (r = 0.70). The calculated LV volumes had more errors in the Cedars-Sinai program than in the Emory program, when a patient had a small heart.

Adult↗
PubMed2000

Simultaneous assessment of Tc-99m-sestamibi and I-123-BMIPP myocardial distribution in patients with myocardial infarction: evaluation of left ventricular function with ECG-gated myocardial SPECT.

123I-labeled 15-(p-iodophenyl)-3R,S-methyl pentadecanoic acid (BMIPP) is a branched-chain free fatty acid that is used to evaluate various cardiac diseases. The aim of the present study was to investigate the relationship between myocardial perfusion (99mTc-sestamibi) and BMIPP uptake, and to correlate perfusion and metabolic alterations with regional left ventricular dysfunction in patients with myocardial infarction (MI). ECG-gated dual-isotope myocardial SPECT was performed on 130 patients with MI with sestamibi (555 MBq) and BMIPP (148 MBq). The patients were classified into 3 groups according to PTCA therapy and the interval between the onset of infarction and RI injection (OR time). Group A (n = 56) included patients whose OR time was less than one month and who had undergone successful PTCA, Group B (n = 36) had OR times of less than one month and had conservative medical therapy, and Group C (n = 38) had OR times of over one month. The severity scores of the dual-isotope images were calculated from the defect scores in 9 segments. From the ECG-gated SPECT data with sestamibi, the left ventricular ejection fraction (LVEF; %) and regional wall motion were determined automatically using the QGS program LVEF obtained from gated SPECT correlated well with the severity scores for sestamibi and BMIPP (r = -0.68 and -0.76, respectively). The delta severity scores (BMIPP scores - sestamibi scores) of Group A were significantly higher than those of the other two groups (3.6 +/- 3.0 vs. 1.5 +/- 1.7 and 1.0 +/- 1.4, p < 0.001 ). The rate of dysfunctional segments with normal sestamihi distribution was significantly higher in Group A than in Group C (20.7% vs. 6.7%, p < 0.001). ECG-gated dual-isotope SPECT is useful since myocardial perfusion, fatty acid metabolism and left ventricular function can be analyzed during a single examination, so that this procedure has the potential to provide comprehensive information when evaluating patients with ischemic heart disease.

Adult↗
PubMed1999

Left ventricular function at rest and during bicycle exercise in normal subjects: assessment by ECG-gated myocardial perfusion SPET with 99Tcm-tetrofosmin.

99Tcm-labelled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function using ECG-gated SPET. The aim of this study was to evaluate left ventricular performance during exercise by means of ECG-gated myocardial perfusion SPET. After the administration of 99Tcm-tetrofosmin (555-740 MBq), eight healthy volunteers aged 27-49 years underwent ECG-gated myocardial perfusion SPET at rest and during supine submaximal exercise (75 and 125 W), for 3 min each. Using ECG-gated SPET data, left ventricular end-diastolic volume (LVEDV) demonstrated a biphasic response during exercise (from 106.4 +/- 17.5 to 119.9 +/- 19.9 to 108.1 +/- 19.2 ml). In contrast, left ventricular end-systolic volume decreased gradually and significantly during exercise (from 47.1 +/- 11.9 to 41.5 +/- 8.9 to 36.1 +/- 10.1 ml; P < 0.05), and left ventricular ejection fraction continued to increase at higher workloads (from 56.1 +/- 6.0 to 63.0 +/- 2.7 to 67.0 +/- 4.3; P < 0.01) despite a fall in LVEDV. There was a progressive increase in cardiac output during exercise, which reached a peak of 7.2 +/- 0.9 l.min-1. We conclude that ECG-gated myocardial perfusion SPET can assess left ventricular function during exercise and may provide useful information for the evaluation of patients with ischaemic heart disease.

Adult↗
PubMed1999

[Myocardial distribution of iodine-123-iodophenyl-9-methyl-pentadecanoic acid (9MPA) in patients with acute myocardial infarction: comparison with regional wall motion obtained from technetium-99m-sestamibi gated SPECT].

123I-iodophenyl-9-methyl-pentadecanoic acid (9MPA) is a modified long-chain (15 carbons) fatty acid with a methyl branch on its 9 carbon location. Myocardial SPECT images (two sets, 10 min each) were obtained starting 10 min (early phase) and 50 min (delay phase) after the injection of 160 MBq 123I-9MPA at rest in 10 patients with acute myocardial infarction. The segmental myocardial uptake (% uptake) and clearance (% washout) from early to delay image were calculated by the SPECT data. ECG-gated myocardial SPECT with 99mTc-sestamibi was also performed and segmental left ventricular (LV) wall motion was evaluated using QGS (quantitative gated SPECT) program. The % uptake of LV segments with hypokinetic or akinetic wall motion were significantly lower than those with normokinesis (p < 0.01) for both early and delay phases. The % washout of hypokinetic segments were significantly lower than those of normokinetic regions (p < 0.01), while the % washout of akinetic segments were significantly higher than those of severely hypokinetic segments (p < 0.05). Thus, 123I-9MPA myocardial distribution and clearance thought to be associated with left ventricular regional wall motion.

Fatty Acids↗
PubMed1999

[Composition of vascular tree using moving-table MR angiography: development and preliminary clinical experience with a semi-automated program combining stacks of MR angiographic images].

Moving-table MR angiography, combining a contrast enhanced MRA approach with table movement, has recently become available. This technique allows imaging of long, longitudinal anatomical regions of vasculature. We have developed a semi-automated program combining stacks of MRA images obtained from different image stations, and applied it to the reconstruction of vascular trees in twenty-five patients with peripheral arterial occlusive disease. Using this program, continuous vascular trees, extending from the abdominal aorta to lower leg (up to 124 cm), were semi-automatically reconstructed within two minutes from six different projection angles. Extensive vascular lesions were recognized three-dimensionally by moving image display mode.

Arterial Occlusive Diseases↗
PubMed1999

[Assessment of left ventricular contraction abnormalities with myocardial infarction using gated technetium-99m sestamibi SPECT: comparison of wall thickening and regional ejection fraction analysis for the detection of coronary artery stenosis].

ECG-gated myocardial Technetium-99m sestamibi SPECT is a useful technique to measure myocardial perfusion and function simultaneously. In this study, wall thickening (WT) and regional ejection fraction (rEF) using ECG-gated SPECT have been studied to determine which parameter would be more sensitive to detect coronary artery stenosis in patients with acute myocardial infarction (AMI). Forty-five patients (36 men, 9 women, mean age 63 +/- 9 years old) with AMI were examined. CAG was performed for all patients. ECG-gated SPECT was performed 60 min after the intravenous injection of 555 MBq 99mTc-sestamibi at rest. Commercially available software (QGS) was used to produce WT and rEF polar maps from acquired SPECT data. The WT and rEF polar maps were evaluated visually and quantitatively. WT indicated higher sensitivity (80.3% vs. 59.1%, p < 0.05) and accuracy (86.7% vs. 74.8%, p < 0.05) than rEF for detecting overall coronary artery stenosis on visual interpretation. On quantitative analysis, WT had higher specificity (91.3% vs. 75.4%, p < 0.05) and accuracy (85.9% vs. 72.6%, p < 0.05) than rEF for detecting overall coronary artery stenosis, and showed a higher specificity (93.8% vs. 59.4%, p < 0.01) and accuracy (88.9% vs. 62.2%, p < 0.01) for detecting LCX stenosis. Moreover, sensitivity of WT for detecting coronary artery stenosis without infarction was higher than that of rEF significantly in quantitative analysis (75.0% vs. 31.3%, p < 0.05). These results suggested that WT was superior to rEF for detecting the coronary artery stenosis in patients with and without myocardial infarction. We concluded that WT is more sensitive indicator to determine localization of regional left ventricular dysfunction in AMI than rEF.

Aged↗
PubMed1998

Rapid data acquisition protocol in ECG-gated myocardial perfusion SPECT with Tc-99m-tetrofosmin.

Into 25 patients with heart disorders, 99mTc-tetrofosmin 555-740 MBq was injected intravenously at rest. After 40 minutes, ECG-gated myocardial perfusion SPECT was performed with a two detector gamma camera VERTEX (ADAC), setting up two detectors to form a 90-degree angle. Sixteen frames per R-R interval were acquired during a 180 degree rotation from the RAO 45 degrees to the LPO 45 degrees. A pair of data sets with standard (SDA) and rapid data acquisition (RDA) protocols was collected. In an SDA protocol, SPECT imaging was performed for 50 sec per step in 5 degree angular steps (total acquisition time; 15 minutes). An RDA protocol was conducted with 12 sec per step, 6 degree angular steps (acquisition time, 3 minutes). LVEF (%) and LVEDV (ml) quantitated automatically with a QGS program showed excellent correlations between two protocols with correlation coefficients of 0.980 (p < 0.01) and 0.983 (p < 0.01), respectively. Subsequently visual assessment of regional wall motion based on a four-point grading system was carried out with a 3-D cine LV display. High complete agreement was gained with 158 (90.3%) out of total 175 segments, so that assessment of the global and regional LV function with the RDA protocol demonstrated high reliability and feasibility.

Electrocardiography↗
PubMed1998

The discrepancy between 99Tcm-ECD dynamic and static SPET images in patients with ischaemic lesions corresponds to reduced vasoreactivity to acetazolamide.

We evaluated 99Tcm-N,N'-(1,2-ethylenediyl)bis-L-cysteine diethyl ester (99Tcm-ECD) dynamic and static SPET (single photon emission tomographic) images to examine 99Tcm-ECD kinetics under ischaemic cerebrovascular conditions. In 20 patients who showed arterial occlusion on magnetic resonance angiography, dynamic (0-10 min) and static (15-35 min) SPET images were acquired after the intravenous administration of 99Tcm-ECD. Thirteen of the patients had focal perfusion deficits that were more evident on the dynamic than on the static images; the other seven showed no such discrepancy. In those patients with a mismatch between the dynamic and static images, the extent corresponded to reduced vaso-reactivity to acetazolamide. Based on quantitative analysis of the ratio of tracer uptake in affected to that in unaffected areas, the patients with discrepant findings showed significantly different ratios on the dynamic and static images, whereas those with no such mismatch did not. Our results suggest that dynamic 99Tcm-ECD images provide circulatory information and that static images reflect a filling-in phenomenon of ECD metabolites in ischaemic lesions. 99Tcm-ECD dynamic and static SPET images offer an alternative method of detecting mild perfusion deficits without the need for acetazolamide challenge.

Acetazolamide↗
PubMed1998

[Study on the clinical characteristics of double cancers associated with renal cell carcinoma].

BACKGROUND: Clinical Features of double cancers associated with renal cell carcinoma (RCC) detected at the clinical course, especially focusing on the comparative analysis between the male and female patients, were unknown. From this background, we tried to search for clinical characteristics of double cancers associated with RCC. PATIENTS: The eight hundred and four patients with RCC have been treated at our University Hospitals and affiliated hospitals, and of them, the 38 patients (male in 25, female in 13) had double cancers during the clinical course, and these patients were objective in our study. RESULTS: 1) When we looked at all patients, there observed gastric cancer most frequently in 14 (36.8%), lung cancer in 3 (7.9%), prostate cancer in 3, bladder cancer in 3, uterine cancer in 3, rectal cancer in 2 (5.3%), thyroid cancer in 2, and pharynx, esophagus, T-cell lymphoma, chronic lymphatic leukaemia (CLL), renal pelvis, sigmoid colon, brain and colon cancers in 1 (2.6%) respectively. 2) As to the male patients, there observed 10 gastric cancers, of them, 2 died of this disease (20%), 3 lung cancers, of them, 2 died of this disease (66.7%), 3 prostate cancers, of them, 2 died of this disease (66.7%), 3 bladder cancers, of them, 1 died of this disease (33.3%), and 1 cancer patient with pharynx died of this disease, esophagus, T-cell lymphoma, CLL, renal pelvis and sigmoid colon died of this disease. Regarding the female patients, there observed 4 gastric cancers, all of them died of this disease, 3 uterine cancers, all of them died of this disease, 2 rectum cancers, all of them died of this disease, 2 thyroid cancers, of them, 1 died of this disease, 1 brain cancer and 1 rectal cancer. Furthermore, as to the timing at the detection of double cancers during the clinical course, the 10 patients (40%) detected double cancers simultaneously in male patients. On the other hand, no patient with double cancers was detected simultaneously in female patients. CONCLUSION: The gastric cancer is most frequently observed as double cancer in both of male and female patients with RCC. But, in the female patients, it shows more frequently died of double cancers associated with RCC compared with those in male. Furthermore, as to the timing at the detection of double cancer is asynchronous in all female patients with RCC.

Adult↗
PubMed1997

[Foreskin retraction for phimosis of the newborn].

BACKGROUND: No guideline exists on how to treat boy's phimosis. We examined if retraction of the foreskin of the newborn boy's penis could make true phimosis become false phimosis. METHODS: We taught the mother to retract the foreskin and keep inside the foreskin clean. Exposure degree of glans by retraction of foreskin was defined in 7 grades, 0 (none) approximately III (middle) approximately VI (full). RESULTS: Of the 538 newborn examined, none had full exposure (VI). All of the 372 cases who continued the procedure, including 2 buried penis, gained full exposure (VI). Average time for full exposure according to the first degree of exposure was 2.94 months (0), 1.78 months (III), 1.22 months (V), 2.32 months average, respectively. No serious complications occurred. CONCLUSION: Retraction of the foreskin from the newborn period made all the true phimosis to be false phimosis and operative procedures became unnecessary.

Health Education↗
PubMed1997

[Stone recurrence after stone free status with extracorporeal shock wave lithotripsy].

BACKGROUND: The objects of this study is to evaluate the ipsilateral stone recurrence who became stone free status after extracorporeal shock wave lithotripsy (ESWL). METHODS: Three hundred ninety five patients who became stone free after ESWL with Lithostar and followed more than 6 months, were analyzed stone recurrence. Stone recurrence were diagnosed by KUB and/or ultrasound. Actual recurrence free rate were calculated based on the period from the day of achieved stone free status to the day of estimated recurrence. Eight factors examined included sex, side, number, location, size, stone history urological complication, hydronephrosis and also contralateral recurrence was analyzed. RESULTS: Over all ipsilateral recurrence free rate were 96.5%, 78.8%, 65.3% after 1, 3 and 5 years, respectively. Contralateral stone free rate were 98.1%, 92.5%, 87.2% after 1, 3 and 5 years. Five-year recurrence free rate according stone factors, there were significant difference in stone number (Single 71.1% and multiple 31.6%), in stone history (with history 77.1% and without 35.7%), in urological complication (without complication 67.7% and with complication 35.7%). However, there were no significant difference in sex, side, stone, location, stone size and hydronephrosis. CONCLUSION: This results suggested that the stone number, stone history and urological complication were highly related to ipsilateral stone recurrence after stone free status by ESWL. Extracorporeal shock was lithotripsy had probability of higher stone recurrence rate.

Adolescent↗
PubMed1997

[Study of the effects of treatment with interferon for the advanced renal cell carcinoma based upon the survival rate].

BACKGROUND: There is no consistent acknowledgment with the effects of the prolongation of survival for the advanced renal cell carcinoma (RCC) treated with interferon (IFN). Therefore, we tried to study on the effects of such prolongation of survival for the advanced RCC through the comparative analysis between the patients treated with IFN and the patients treated with other treatment modalities in the past years. PATIENTS AND METHODS: We differentiated the patients treated with IFN (recurrent patients after nephrectomy as Group I, and patients with stage 4B as Group II) from the patients treated with other modalities (recurrent patients after nephrectomy as Group III, and patients with stage 4B and Group IV). We compared the survival rate between the two groups (Groups I vs III, and Groups II vs IV). RESULTS: Regarding the various factors affecting prognosis of RCC, no significant difference was observed among these groups. 1) There observed a significantly favorable survival rate in the Group I compared with the Group III, and the same result was observed in the Group II compared with the Group IV. 2) In the patients with performance status (P.S.) 0 and low grade, there observed a significantly favourable survival rate in the Group I compared with the Group III, and the same result was observed in the Group II compared with the Group IV. Furthermore, in the patients with low stage, the Group I showed a significantly favourable survival rate compared with the Group III. 3) In the study on the number of metastatic organs (1, 2 and 3 organs or more), there observed a significantly favourable survival rate in the Group I compared with the Group III for all numbers of the metastatic organs. The same result was observed in the group II compared with the Group IV, except for the patient with 3 organs or more. Regarding the operative procedures for the metastatic side, the patients who did not receive the operative procedures showed a significantly favourable survival rate in the Group I compared with the Group III. The same result was observed in the Group II compared with the Group IV. 4) As to the survival rate based upon the response rate, only the patients with no change (N.C.) showed a significantly favourable survival rate in the Group I compared with the Group III. The same result was observed in the Group II compared with the Group IV. CONCLUSION: We conclude that the treatment with IFN for the advanced RCC would much contribute to the prolongation of the survival in comparison with the previous patients who received other treatments.

Adolescent↗
PubMed1997

[Case report on the patient who showed a primary lung carcinoma accompanied with lung metastasis from renal cell carcinoma simultaneously during the clinical follow-up].

BACKGROUND: We have studied on the patient who showed a primary lung carcinoma and microscopic metastasis from renal cell carcinoma simultaneously after nephrectomy for renal cell carcinoma. PATIENT: A 57-year-old man who had an incidentally discovered right renal cell carcinoma at the time of the examination of different disease, and received nephrectomy. Two years and four months after nephrectomy, a solitary primary lung carcinoma was found. Therefore, he received lobectomy. Histopathological examination revealed that the lung tumour was a poorly differentiated adenocarcinoma, and peripheral lesions of the lung tumour, it was also discovered small clear-cell carcinoma simultaneously. At that time, we could not diagnose this carcinoma as a metastatic renal cell carcinoma. Nine months after lobectomy, new coin lesions were appeared in the lung. Therefore, we diagnosed a minimum clear lesion which was found nine months ago was metastatic renal cell carcinoma clinically. At present, the patient receives interferon-alpha therapy. RESULTS: As a result, we diagnosed primary lung carcinoma and small metastatic renal cell carcinoma simultaneously. However, the latter diagnosis could be obtained through the progression of the disease. CONCLUSION: We conclude that we must give heed to the patients with new cancerous lesions histologically when the patients treated of cancer previously.

Adenocarcinoma, Clear Cell↗
PubMed1996

[Clinicopathological study on patients with chromophobe cell renal carcinoma].

BACKGROUND: Reports on the patients with chromophobe cell renal carcinoma were very few. Therefore, the clinical features of this disease are uncertain. Based upon this background, we have studied on the clinicopathological characteristics of chromophobe cell renal carcinoma. PATIENTS AND METHODS: From 1957 to 1995, seven hundred and fifty-one patients with renal cell carcinoma (RCC) were treated at the Jikei University Hospitals. Of these patients, 36 (4.8%) with chromophobe cell renal carcinoma were diagnosed by histopathological examination. Of these 36 patients, the objective patients were 34 who could be followed-up along with long interval. RESULTS: The age distribution was 28 to 83 years old (mean was 54.1 years). Regarding to the sex difference, there observed male in 22 patients and female in 12 patients (sex ratio was 1.8: 1). Furthermore, the affected side was even, but there observed the symptoms of urinary tract mainly of haematuria in 24 patients (76.5%). As to the laboratory examination, there observed the abnormality of the acute phase reactants in 20% of patients. The greater diameter of the tumour was distributed from 1.5 to 17 cm (mean: 6.9 cm), and no consistent tendency of tumour localization was observed. Regarding the preoperative angiography, there observed the hypovascular/ avascular pattern in 15 patients (44.1%). As to the stage and grade, there observed the low stage patients in 30 (88.2%) and low grade patients in 27 (79.4%). With respect to the prognosis, the 1, 3, 5, 10, 15 and 20 years survival rates for chromophobe cell renal carcinoma were 97.1%, 81.6%, 81.6%, 70.2%, 61.9% and 46.7% respectively. After comparing the survival rate of the same stage and grade patients between the objected patients and the common types of RCC, there observed a favourable prognosis in the patients with chromophobe cell renal carcinoma. Especially in patients with eosinophilic variant, no cancer related death was observed. CONCLUSION: The clinicopathological characteristics of chromophobe cell renal carcinoma show the hypovascular/avascular in angiography, low rate of laboratory abnormality, low stage/ low grade and a favourable prognosis compared with the common types of RCC.

Adenocarcinoma↗
PubMed1996

[Study on anti-tumour effects of interleukin 12 for spontaneously arose murine renal cell carcinoma].

BACKGROUND: We studied on the anti-tumour effects of recently cloned cytokine interleukin-12 (IL-12) for murine renal cell carcinoma (RC-2) with special reference to the difference of its activity based upon the different method of administration. MATERIALS AND METHODS: Ten days after RC-2 inoculation to subcutaneous of BALB/C mice, the recombinant murine IL-12 (rMu-IL-12 was administered (0.5 microgram/mouse, 1.0 microgram/mouse and 2.0 micrograms/mouse) 5 times per week for 3 weeks. Two administration methods were applied: intraperitoneal administration (i.p.) and subcutaneous administration near grown tumour (s.c.). We evaluated the efficacy of IL-12 for the RC-2 by means of the ratio of relative mean tumour weight (TRW/CRW), the degree of histological degeneration and the survival time of tumour-bearing mice. Furthermore, the serial body weight of mice excluding the tumour weight was monitored in order to evaluate the side effect of IL-12. RESULTS: 1) The ratio of TRW/CRW: As to the experiment of IL-12 injected at 0.5 microgram/mouse, the anti-growth effect was more potent in the i.p. group than in the s.c. group. On the other hand, as to the higher dose groups including 1.0 microgram/mouse and 2.0 micrograms/ mouse groups, the s.c. groups showed more potent anti-tumour growth effects than the i.p. groups. 2) The histological effect: All examined groups showed the degree of grade II degeneration which meant the existence of viable tumour cells after the treatment had been finished. Furthermore, we found out the different pattern of degeneration between the two administration groups (i.p. and s.c.). Namely, there observed sporadicaly degeneration in the i.p. groups, and also observed uniform degeneration close to the injected area in the s.c. groups. 3) Survival time: All treated groups showed a significant prolongation of survival compared with the control, but no significant difference was observed between these two different injected groups. 4) Side effects: Through monitoring serial changes of body weight of treated mice, no significant decrease of body weight due to the administration of IL-12 was observed in all experiments. CONCLUSION: The anti-tumour effects of IL-12 for murine renal cell carcinoma with special reference to the difference of anti-tumour effect based upon the different method of administration shows that more potent anti-tumor growth effects are observed in the i.p. group dosed at 0.5 microgram/mouse than in the s.c. group. On the other hand, as to the escalating doses, more potent anti-tumour effects are observed in the s.c. groups than in the i.p. groups. Through all treatment groups, no complete regression of the tumour is observed. Therefore, further precise study to clarify the immunological reaction between tumour and its host derived from the administration of IL-12 must be needed in order to establish more effective treatment with IL-12 in the future.

Animals↗