[Usefulness of (18)F-FDG PET/CT for detecting lesions in patients with POEMS syndrome].

Many patients with POEMS syndrome have osteosclerotic plasmacytoma. Radiation therapy is useful for patients who have localized lesions, although chemotherapy is necessary for patients who have widespread lesions. Thus, evaluation of these lesions is important to determine the therapeutic strategy. We evaluated the activities of lesions in two patients with POEMS syndrome by (18)F-FDG positron emission tomography (PET)/computed tomography (CT) scan. In the first patient, PET/CT scan revealed osteosclerotic lesions, which were not detected by Ga-scintigraphy or plain X-ray. It also detected residual disease activity and relapse. In the second patient, lymph node involvement was suggested by (18)F-FDG uptake, and plasmacytoma was confirmed by subsequent biopsy. In the extramedullary lesions of this case, FDG uptake was as marked as in myeloma, whereas bone lesion was only detectable by CT scan. In POEMS syndrome, the PET and CT are complementary, and the combined PET/CT scan is considered to be very useful for evaluation of involved lesions.

[Assessment of the efficacy, safety and pharmacokinetics of SKG-02 (recombinant human TSH) in postoperative diagnosis of well-differentiated thyroid cancer--a Japanese prospective, controlled, multicenter open-label study].

OBJECTIVE: This study sought to assess the safety, efficacy, impact on hypothyroid symptoms, and pharmacokinetics of SKG-02 (rhTSH, thyrotropin alfa) in the diagnostic follow-up of Japanese patients with well-differentiated thyroid carcinoma (WDTC). METHODS: Ten Japanese adults with WDTC were enrolled into a prospective, multicenter, open-label trial comparing diagnostic whole-body scintigraphy (dxWBS) and serum thyroglobulin (Tg) testing aided by SKG-02 versus these procedures aided by thyroid hormone withdrawal (THW). Patients were their own controls. Variables compared included scan set ability to detect radioiodine uptake by remnant or malignant thyroid tissue, scan set quality, diagnostic sensitivity of dxWBS and Tg testing alone or combined, frequency of hypothyroid signs/symptoms, and adverse events (AEs). SKG-02 pharmacokinetic variables including maximum concentration (Cmax), time to Cmax (Tmax) and the area under the time-concentration curve (AUC) were calculated. RESULTS: In a blinded evaluation by an independent committee of 3 nuclear medicine experts, 70% of SKG-02 dxWBS scan sets were rated "equivalent" (n = 7) or "superior" (n = 0) to their THW counterparts in ability to detect radioiodine uptake in healthy or malignant thyroid tissue. Therefore the study exceeded its primary endpoint of a 60% equivalence/superiority rate. SKG-02 Tg testing identified 3/3 cases of disease. Hypothyroid signs/symptoms were substantially more frequent during THW than during euthyroidism permitted by SKG-02 use. SKG-02 was well-tolerated, with no severe or serious drug-related AEs. Cmax was 240.8 +/- 65.9 microIU/ml, Tmax was 28.75 +/- 14.21 hr after the first SKG-02 injection, and AUC was 11,414 +/- 3,462 microIU hr/ml in 9 patients evaluable for pharmacokinetics. CONCLUSIONS: SKG-02 was safe and effective in the diagnostic follow-up of Japanese patients with WDTC, avoiding hypothyroid morbidity relative to THW. These and the pharmacokinetic findings were similar to those of overseas Phase III studies.

Comparison of imaging protocols for 18F-FDG PET/CT in overweight patients: optimizing scan duration versus administered dose.

UNLABELLED: The quality of (18)F-FDG PET/CT images of overweight patients is often degraded. We evaluated the effect of optimizing injected dose or acquisition time on the quality of images of overweight patients using lutetium oxyorthosilicate PET/CT with high-performance detector electronics. METHODS: We initially retrospectively measured radioactivity concentrations and signal-to-noise ratios (SNRs) in the liver relative to body weight for 80 patients who had undergone (18)F-FDG PET/CT according to our standard protocol (injected dose, 3.7 MBq/kg; acquisition time, 2 min/bed position). The patients were grouped (n = 20 per group) according to baseline body weight as G1 (or=85 kg). We compared the SNRs of G1 with those of G2, G3, and G4 and calculated the ratio squared as a factor to correct the acquisition parameters for overweight patients. We then prospectively enrolled 120 patients according to the same body weight criteria. We multiplied the correction factors to optimize injected doses or acquisition times and defined dose-adjusted groups (n = 20 per group) and time-adjusted groups (n = 20 per group). G2 dose was defined as 5.59 +/- 0.19 MBq/kg, G3 dose as 7.29 +/- 0.33 MBq/kg, and G4 dose as 8.88 +/- 0.43 MBq/kg. G2 time was defined as 3 min/bed position, G3 time as 4 min/bed position, and G4 time as 5 min/bed position. RESULTS: Although liver activities did not significantly differ among G1 through G4 irrespective of patient weight, SNR progressively decreased as patient weight increased. The liver activities of G2 dose, G3 dose, and G4 dose were, respectively, 1.4-, 1.9-, and 2.5-fold higher than those of the baseline counterparts. Nevertheless, the increased liver activities of G2 dose, G3 dose, and G4 dose did not significantly affect SNR, compared with the baseline groups. In contrast, the SNR of G4 time was significantly higher than that of G4. CONCLUSION: Our findings suggest that the quality of images acquired from heavier patients can be maintained only by scanning for longer periods. Increasing the dose per kilogram of body weight did not improve the quality of lutetium oxyorthosilicate PET/CT images.

Prognostic significance of stress myocardial ECG-gated perfusion imaging in asymptomatic patients with diabetic chronic kidney disease on initiation of haemodialysis.

PURPOSE: Diabetic patients with chronic kidney disease (CKD) frequently develop cardiac events within several years of the initiation of haemodialysis. The present study assesses the prognostic significance of stress myocardial ECG-gated perfusion imaging (MPI) in patients with diabetic CKD requiring haemodialysis. METHODS: Fifty-five asymptomatic patients with diabetic stage V CKD and no history of heart disease scheduled to start haemodialysis were enrolled in this study (56 +/- 11 years old; 49 with type 2 diabetes mellitus). All patients underwent (201)Tl stress ECG-gated MPI 1 month before or after the initiation of haemodialysis to assess myocardial involvement. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score (SSS) and summed difference scores (SDS). The patients were followed up for at least 2 years (42 +/- 15 months) to determine coronary intervention (CI) and heart failure (HF) as soft events and acute myocardial infarction (AMI) and all causes of deaths as hard events. RESULTS: The frequencies of myocardial ischaemia, resting perfusion defects, low ejection fraction and left ventricular (LV) dilatation were 24, 20, 29 and 49%, respectively. Ten events (18%) developed during the follow-up period including four CI, one HF, one AMI and four sudden deaths. Multivariate Cox analysis selected SDS (p = 0.0011) and haemoglobin A(1c) (HbA(1c)) (p = 0.0076) as independent prognostic indicators for all events. CONCLUSION: Myocardial ischaemia, in addition to glycaemic control, is a strong prognostic marker for asymptomatic patients with diabetic CKD who are scheduled to start haemodialysis. Stress MPI is highly recommended for the management and therapeutic stratification of such patients.

[The 29th report on survey of the adverse reaction to radiopharmaceuticals (the 32nd survey in 2006)].

This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2006 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 975 institutions among 1263 to which the questionnaire had been sent. Thirty-two cases of adverse reactions were reported. A total of 1,189,127 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 2.7. Three cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.3.

Myocardial kinetics of (201)Thallium, (99m)Tc-tetrofosmin, and (99m)Tc-sestamibi in an acute ischemia-reperfusion model using isolated rat heart.

OBJECTIVE: (201)Thallium (TL), (99m)Tc-tetrofosmin (TF), and (99m)Tc-sestamibi (MIBI) are extensively used as myocardial perfusion agents. The objective of the present study was to evaluate their kinetics under acute ischemia-reperfusion. METHODS: Isolated rat hearts, perfused by the Langendorff method at a constant flow rate of 10 ml/min, were allotted to normal control, mild ischemia, and severe ischemia groups, in which 20-min tracer wash-in was conducted followed by a 25-min tracer washout. No-flow ischemia (15 min for mild ischemia groups; 30 min for severe ischemia groups) was induced before conducting wash-in and washout in the ischemia groups. Whole-heart radioactivity was determined with an external gamma detector. Myocardial flow rate (K (1), ml/min) and clearance rate (k (2), min(-1)) were calculated. RESULTS: K (1TL), K (1TF), and K (1MIBI) decreased according to the severity of ischemia (K (1TL) 5.32 +/- 0.53, 4.76 +/- 0.70, and 1.44 +/- 0.59; K (1TF) 3.80 +/- 0.70, 2.73 +/- 0.99, and 1.09 +/- 0.45; and K (1MIBI) 3.45 +/- 1.10, 2.15 +/- 0.82, and 1.05 +/- 0.13, in the normal control, mild, and severe ischemia groups, respectively). K (1) was significantly higher for TL than for the (99m)Tc tracers (P < 0.05), but the (99m)Tc tracers had equivalent K (1) values. k (2TL) increased significantly (P < 0.05) in the ischemia groups (k (2TL) 0.062 +/- 0.013, 0.11 +/- 0.045, and 0.12 +/- 0.035), but showed no significant difference between the ischemia groups. k (2MIBI) and k (2TF) were significantly (P < 0.05) lower than k (2TL) and increased significantly (P < 0.05) in the severe ischemia group (k (2TF) 0.0056 +/- 0.0022, 0.0037 +/- 0.0015, and 0.024 +/- 0.015; and k (2MIBI) 0.00072 +/- 0.0011, 0.00038 +/- 0.00076, and 0.042 +/- 0.034). k (2MIBI) was significantly (P < 0.05) lower than k (2TF) in the normal control and mild ischemia groups. CONCLUSIONS: Tracer extraction was higher for TL than for the (99m)Tc tracers and all tracers decreased according to the severity of ischemia-reperfusion in the three tracer groups. The clearance kinetics of not only MIBI but also TF is possibly useful for the evaluation of the severity of ischemia, and the Langendorff method and a methodological approach by continuous determinations of radioactivity may serve for the quantitative analysis of tracer kinetic profiles.

Prognostic value of 123I-metaiodobenzylguanidine in patients with various heart diseases.

OBJECTIVE: It has been reported that (123)I-metaiodobenzylguanidine (MIBG) scintigraphy can predict the poor prognosis in patients with dilated cardiomyopathy (DCM). However, the prognostic significance of MIBG is still unknown in patients with other heart diseases. In this study, we compared the prognosis and MIBG findings in various heart diseases. METHODS: Consecutive 565 patients undergoing MIBG scintigraphy were enrolled (392 men, 52 +/- 16 years). Indications were that 127 had ischemic heart disease (IHD), 120 DCM, 101 hypertrophic cardiomyopathy (HCM), 21 hypertensive heart disease (HHD), 58 volume-load valvular disease (VVD), 38 pressure-load valvular disease (PVD), and 101 ventricular tachycardia or fibrillation (VTF). Heart-to-mediastinum ratio (H/M) and washout rate (WR) of MIBG were evaluated. Cardiac events were defined as sudden cardiac death, heart failure, and acute ischemic event (follow-up, 22.7 +/- 17.0 months). RESULTS: A total of 106 cardiac events including 40 cardiac deaths occurred. Cox hazard model analysis showed that in the IHD, HCM, and DCM groups, H/M and WR were associated with cardiac death, but not in the HHD, PVD, VVD, or VTF groups. Only death and congestive heart failure (CHF) episodes were related to H/M and WR. On the other hand, fatal arrhythmia, myocardial infarction, or angina pectoris were not related to H/M and WR. The data indicated that WR or H/M may predict death and CHF but does not predict fatal arrhythmia or acute ischemic event. CONCLUSIONS: MIBG WR and H/M were associated with heart failure, sudden death, and cardiac death events, and were useful to predict the prognosis in DCM, HCM, and IHD. In contrast, fatal arrhythmia events were not associated with MIBG indices, and thus it does not appear to be useful in predicting cardiac events in patients with VTF.

[The 28th report on survey of the adverse reaction to radiopharmaceuticals (the 31st survey in 2005)].

This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2005 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 1,007 institutions among 1,243 to which the questionnaire had been sent. Nineteen cases of adverse reactions were reported. A total of 1,264,098 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 1.5. Three cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.2.

Accuracy of PET for diagnosis of solid pulmonary lesions with 18F-FDG uptake below the standardized uptake value of 2.5.

UNLABELLED: Benign and malignant pulmonary lesions usually are differentiated by 18F-FDG PET with a semiquantitative 18F-FDG standardized uptake value (SUV) of 2.5. However, the frequency of malignancies with an SUV of <2.5 is significant, and pulmonary nodules with low 18F-FDG uptake often present diagnostic challenges. METHODS: Among 360 consecutive patients who underwent 18F-FDG PET to evaluate pulmonary nodules found on CT, we retrospectively analyzed 43 who had solid pulmonary lesions (excluding lesions with ground-glass opacity, infiltration, or benign calcification) with an SUV of <2.5. The uptake of 18F-FDG was graded by a visual method (absent, faint, moderate, or intense) and 2 semiquantitative methods (SUV and contrast ratio [CR]). Final classification was based on histopathologic findings or at least 6 mo of clinical follow-up. RESULTS: We found 16 malignant (diameter, 8-32 mm) and 27 benign (7-36 mm) lesions. When faint visual uptake was the cutoff for positive 18F-FDG PET results, the receiver-operating-characteristic (ROC) analysis correctly identified all 16 malignancies and yielded false-positive results for 10 of 27 benign lesions. Sensitivity was 100%, specificity was 63%, and the positive and negative predictive values were 62% and 100%, respectively. When an SUV of 1.59 was the cutoff for positive 18F-FDG PET results, the ROC analysis revealed 81% sensitivity, 85% specificity, and positive and negative predictive values of 77% and 89%, respectively. At a cutoff for positive 18F-FDG PET results of a CR of 0.29, the ROC analysis revealed 75% sensitivity, 82% specificity, and positive and negative predictive values of 71% and 85%, respectively. The areas under the curve in ROC analyses did not differ significantly among the 3 analyses (visual, 0.84; SUV, 0.81; and CR, 0.82). Analyses of intra- and interobserver variabilities indicated that visual and SUV analyses were quite reproducible, whereas CR analysis was poorly reproducible. CONCLUSION: These results suggested that for solid pulmonary lesions with low 18F-FDG uptake, semiquantitative approaches do not improve the accuracy of 18F-FDG PET over that obtained with visual analysis. Pulmonary lesions with visually absent uptake indicate that the probability of malignancies is very low. In contrast, the probability of malignancy in any visually evident lesion is about 60%.

[The 27th Report on Survey of the Adverse Reaction to Radiopharmaceuticals (the 30th survey in 2004)].

This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals and defect products in FY2004 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 968 institutions among 1,220 to which the questionnaire had been sent. Sixteen cases of adverse reactions were reported. A total of 1,277,906 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 1.3. Eight cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.6.

Probability of axillary lymph node metastasis when sentinel lymph node biopsy is negative in women with clinically node negative breast cancer: a Bayesian approach.

BACKGROUND: Although sentinel lymph node biopsy(SLNB)is highly accurate in predicting axillary nodal status in patients with breast cancer, it has been shown that the procedure is associated with a few false negative results. The risk of leaving metastatic nodes behind in the axillary basin when SLNB is negative should be estimated for an individual patient if SLNB is performed to avoid conventional axillary lymph node dissection(ALND). METHODS: A retrospective analysis of 512 women with T1-3N0M0 breast cancer was conducted to derive a prevalence of nodal metastasis by T category as a pre-test(i.e., before SLNB)probability and to examine potential confounders on the relationship between T category and axillary nodal involvement. Probability of nodal metastasis when SLNB was negative was estimated by means of Bayes' theorem which incorporated the pre-test probability and sensitivity and specificity of SLNB. RESULTS: Axillary nodal metastasis was observed in 6.1% of T1a-b, 25.1% of T1c, 28.7% of T2, 35.0% of T3 tumors. Point estimates for the probability of nodal involvement when SLNB was negative ranged from 0.3-1.3% for T1a-b, 1.6-6.3% for T1c, 2.0-7.5% for T2, and 2.6-9.7% for T3 tumors with representative sensitivities of 80%, 85%, 90% and 95%, respectively. The risk may be higher when the tumor involves the upper outer quadrant of the breast, while it may be lower for an underweight woman. CONCLUSIONS: The probability of axillary lymph node metastasis when SLNB is negative can be estimated using a Bayesian approach. Presenting the probability to the patient may guide the decision of surgery without conventional ALND.

[Guidelines for radio-iodine (131I) therapy in Graves' disease and thyroid cancer].

Radio-iodine (131I) therapy has been using in Graves' disease and well differentiated thyroid cancer. The rules of control in the discharge from radio-isotope hospital were notified in 1999 in Japan. Guideline of the 131I therapy in Graves' disease and thyroid cancer were prepared by sub-group of Japanese Society of Nuclear Medicine.

Scatter correction by two-window method standardizes cardiac I-123 MIBG uptake in various gamma camera systems.

UNLABELLED: Heart to mediastinum count ratio (H/M) has been commonly utilized as an indicator of myocardial I-123 MIBG uptake. However, normal ranges of H/M were markedly different among various gamma camera systems. The purpose of this study was to clarify whether scatter correction by two-window method standardizes H/M among various gamma camera systems. METHODS: Scatter uncorrected and corrected MIBG imaging was acquired in phantom and human studies in combination with low energy high-resolution collimator (LEHR) and medium energy collimator (MEC). For scatter correction, energy window width of 159 keV +/- 10% was applied to main window imaging and 193 keV +/- 9.5% was applied to upper window imaging for scatter correction. RESULTS: In phantom study, a significant difference was observed in uncorrected H/M among three gamma camera systems using LEHR or MEC (2.09 +/- 0.06 vs. 2.58 +/- 0.03 in GCA7200 camera, 2.00 +/- 0.07 vs. 2.42 +/- 0.06 in DS7 camera and 2.16 +/- 0.04 vs. 2.67 +/- 0.07 in Vertex plus camera). However, there was no significant difference in corrected H/M among the three gamma camera systems, either with LEHR or MEC (2.70 +/- 0.07 vs. 2.69 +/- 0.07 in GCA7200 camera, 2.66 +/- 0.08 vs. 2.61 +/- 0.05 in DS7 camera and 2.66 +/- 0.05 vs. 2.61 +/- 0.05 in Vertex plus camera). In human study, uncorrected H/M in DS7 camera with LEHC was significantly lower than that in GCA7200 camera with MEC (1.60 +/- 0.37 vs. 1.85 +/- 0.54, N = 14). In contrast, the difference was insignificant in corrected H/M (2.12 +/- 0.59 vs. 2.16 +/- 0.68). There was a very excellent correlation in corrected H/M between DS7 and GCA7200 cameras (r = 0.991, p < 0.001). CONCLUSION: This study demonstrated that scatter correction by the two-window method standardizes the H/M in MIBG scintigraphy either with LEHR or MEC. Scatter corrected H/M can be applied to measure a standardized parameter of MIBG uptake in human clinical studies using various gamma camera systems.

[The present status of I-131 therapy for Graves' hyperthyroidism in Japan (survey by questionnaire)].

A survey on the I-131 therapy of Graves' hyperthyroidism was undertaken by questionnaire in 1,246 hospitals of Japan. One thousand and ninety seven of them (88.0%) responded to the questionnaire. In this paper, we report the results and analysis of the replies to the questionnaire. In the 121 hospitals (11.03%) of the respondents, I-131 therapy is being performed for Graves' hyperthyroidism. A gradual increase was observed in the annual number of I-131 treated Graves' disease patients during the period of 1998-2001, from 1,740 to 2,484. I-131 treatment was selected mainly for the cases with side effects from antithyroid drug (ATD) therapy, followed by the cases with complication of heart or hepatic diseases, recurrences of hyperthyroidism after surgery, radioiodine treatment, and long-term ATD treatment. The 41% of respondents used I-131 in order to restore euthyroidism, 34% aimed for hyperthyroidism and 41% used the dose properly between the two according to the patients. Administration dosage of I-131 was estimated mainly on the basis of thyroid uptake and volume in 93% of the respondents and 48% calculated the radiation dose by also determining the effective half-life in the thyroid gland. Thyroid size was estimated by scintigram (51%), US (33%), CT (22%) and palpation (12%). ATD treatment was used before I-131 administration by 70% of the respondents and 34% after radioiodine therapy. A low-iodine diet was given to the patients for a week (46%) or two weeks (47%) before I-131 administration. However, after treatment only 46% of the respondents continued low-iodine diet for a week.

[A questionnaire about radiation safety management of the draining-water system at nuclear medicine facilities].

We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0.

[Investigation of radioactivity measurement of medical radioactive waste].

To explore the possibility of which medical radioactive wastes could be disposed as general wastes after keeping them a certain period of time and confirming that their radioactivity reach a background level (BGL), we made a survey of these wastes in several nuclear medicine facilities. The radioactive wastes were collected for one week, packed in a box according to its half-life, and measured its radioactivity by scintillation survey meter with time. Some wastes could reach a BGL within 10 times of half-life, but 19% of the short half-life group (group 1) including 99mTc and 123I, and 8% of the middle half-life group (group 2) including 67Ga, (111)In, and 201Tl did not reach a BGL within 20 times of half-life. A reason for delaying the time of reaching a BGL might be partially attributed to high initial radiation dose rate or heavy package weight. However, mixing with the nuclides of longer half-life was estimated to be the biggest factor affecting this result. When disposing medical radioactive wastes as general wastes, it is necessary to avoid mixing with radionuclide of longer half-life and confirm that it reaches a BGL by actual measurement.

[Phase III additional clinical study of 111In-pentetreotide (MP-1727): diagnosis of gastrointestinal hormone producing tumors based on the presence of somatostatin receptors].

Additional phase III multicenter clinical study was performed to investigate the efficacy, safety, and usefulness of somatostatin receptor scintigraphy using 111In-pentetreotide (MP-1727), which binds to somatostatin receptors. Forty patients were included in the study; Group A: 18 patients, gastrointestinal hormone producing tumors had been detected with conventional imaging modalities, Group B: 22 patients, no tumors had been detected with conventional imaging modalities in spite of high serum hormone levels. By comparing the results of the octreotide suppression test, 12/16 cases (75.0%) of Group A and 11/19 cases (57.9%) of Group B were assessed as "effective." By comparing the results of immunohistological examination, 5/9 cases (55.6%) of Group A and 2/4 cases (50.0%) of Group B were assessed as "effective." Severe adverse events were not observed in any of the evaluable 35 cases. MP-1727 was judged as clinically useful in 11/16 cases (68.8%) of Group A and 5/19 cases (26.3%) of group B. These results suggest that MP-1727 scintigraphy is very useful for the diagnosis and decision of the therapeutic strategy of gastrointestinal hormone producing tumors.