Technetium-99m-MIBI scintimammography by planar and SPECT imaging in the diagnosis of breast carcinoma and axillary lymph node involvement.

BACKGROUND: We compared SPECT and planar (99m)Tc-MIBI scintimammography (SMM) in the detection of primary breast cancer and metastatic axillary lymph node involvement, and the scintigraphic results with the histopathological/cytological findings. MATERIAL AND METHODS: 303 consecutive patients with 308 suspicious or indeterminate lesions observed in mammographies were entered in this study. After an intravenous injection of 740 MBq of (99m)Tc-MIBI, anterior supine, right and left lateral planar images in a prone position and a SPECT study were acquired. RESULTS: 85 malignant and 223 benign breast lesions were confirmed by histopathology/cytology. The overall sensitivity in the detection of breast cancer was 92% (78/85) for SPECT and 82% (70/85) for planar imaging (p = NS), respectively; overall specificity was 91% (204/223) for SPECT and 91% (202/223) for planar scans (p = NS), respectively. Metastatic axillary lymph node involvement was seen in 35 patients; per-axilla overall sensitivity was 66% (23/35) for SPECT and 54% (19/35) for planar images (NS), respectively; overall specificity was 76% (38/50) and 86% (43/50), respectively (NS). CONCLUSIONS: Our results confirm the high diagnostic accuracy of (99m)Tc-MIBI scintimammography in the diagnosis of breast cancer, and show SPECT to be slightly more sensitive than planar imaging, especially in detecting malignant breast lesions. We found the sensitivity of both imaging modalities to be quite low in the detection of metastatic axillary lymph node involvement. SPECT provides additional information to planar SMM with respect to the localization of (99m)Tc-MIBI uptake and tumour extent and improves diagnostic certainty. Our experience suggests that SPECT combined with planar SMM should be used more widely.

Activity and practice of nuclear cardiology in the Czech Republic, 2001.

Radionuclide myocardial perfusion imaging (MPI) has been on the rise in Europe and the USA. Details on nuclear cardiology in the Czech Republic are not available as yet, as it is impossible to obtain comprehensive data from official registers owing to different methods of reporting and data evaluation. A questionnaire concerning nuclear cardiology activity and practice in 2001 was sent to all nuclear medicine departments in the Czech Republic. All 48 departments completed the questionnaire. In 2001, 50 planar and 54 tomographic (SPET) scintillation cameras were used. The average age of the SPET cameras was 5 years (13% of SPET cameras were >8 years old). Out of the 48 centres, 39 (81%) provided a nuclear cardiology service; the total number of cardiological studies was 15,740 in 2001 (1.5 studies/1,000 population/year). The most frequently employed method was MPI (81.7%), the frequency of which had increased by 10% compared with 2000; 26 of the 39 (67%) departments reported that MPI activity was increasing. Nevertheless, the Czech Republic nuclear cardiology activity remained below the European average (2.2/1,000 population in 1994) and, particularly, below activity in the USA (15/1,000 in 1997). The activity was rather unevenly spread. Whereas two centres with >1,000 studies/year accounted for 20% of the total MPI studies, 16 of 39 (41%) departments exhibited low activity (<200 studies/year) and accounted for only 15% of the total MPI studies. The use of SPET increased from 91% in 2000 to 94% in 2001 (only three institutes performed planar examinations). The most widely used tracer was (99m)Tc-MIBI (60% of total MPI), followed by (201)Tl (21%) and (99m)Tc-tetrofosmin (19%). ECG-gated SPET was employed by 20/39 (51%) centres, of which 11 (28%) performed it as a standard examination; 39% of the total MPI studies included this technique. Thirteen percent (5/39) of the departments used attenuation correction, and 69% (27/39) of the departments used a prone projection. Equilibrium radionuclide ventriculography, with 2,317 examinations (14.7%), ranked second among all nuclear cardiology methods, followed by first-pass angiocardiography (406 studies, 2.6%) and (18)F-FDG (163 studies, 1%).

Increased prognostic value of combined myocardial perfusion SPECT imaging and the quantification of lung Tl-201 uptake.

PURPOSE: The authors wanted to identify those patients assessed by exercise SPECT in whom the quantification of lung Tl-201 uptake helps to evaluate disease prognosis. METHODS: One hundred forty-nine patients (114 men, 35 women; 74 after myocardial infarction [MI]; mean age, 54 +/- 9 years) underwent exercise Tl-201 SPECT. The SPECT patterns were divided into normal (n = 45), fixed defects (n = 29), and inducible ischemia (n = 75). Anterior planar imaging was performed before SPECT acquisition to calculate the lung-to-heart ratio (L:H). RESULTS: During an average follow-up of 20 +/- 9 months, eight patients had died of cardiac causes and 13 patients experienced nonfatal MIs. Among the 45 patients with normal perfusion, no cardiac event was observed and the L:H ratio was not helpful for risk stratification. In 29 patients with fixed defects, four cardiac deaths occurred (all in patients with L:H ratios >0.5; annual event rate, 21.1% for L:H ratios >0.5 compared with 0% for L:H ratios <0.5; chi-square = 4.07, P < 0.05). Among the 75 patients with ischemia, 4 died and 13 had nonfatal MIs (annual event rate, 15.4% for L:H ratios >0.5 compared with 13% for L:H ratios <0.5; P = NS). CONCLUSIONS: These findings suggest a benign prognosis in patients with normal SPECT (regardless of the L:H ratio). Conversely, all patients with ischemia are at high risk for future cardiac events. Quantification of the Tl-201 lung uptake seems to be valuable in evaluations of disease prognosis, especially in patients with fixed defects.