The role of 99m Tc-sestamibi scintimammography and colour Doppler ultrasonography in the evaluation of breast lesions.

In the present study we evaluated comparatively the diagnostic value of mammography, of 99mTc-sestamibi scintimammography (sestamibi-SC) and of colour Doppler ultrasonography (CD-US) in 116 breast lesions. Diagnosis was based on histopathological examination. Overall, out of 86 malignant tumours, 80 (93%) and 75 (87%) had a positive sestamibi-SC and positive CD-US, respectively. Out of 30 benign lesions, 25 (83%) and 26 (87%) had a negative sestamibi-SC and negative CD-US respectively. The true positive results were similar in palpable and in non-palpable lesions for both methods. Out of 19 non-palpable malignant tumours, mammography confirmed malignancy in only one case (5%), which was significantly lower than the results obtained by sestamibi-SC (89%; Px0.0001) and by CD-US (74%; P=0.0001). In palpable malignant tumours, by using mamography, true positive results were obtained in 54/67 (80.5%) patients, which was significantly lower than the results obtained by sestamibi-SC (94%; P=0.03) and marginally different to the results obtained by CD-US (91%; P=0.13). It is concluded that sestamibi-SC and CD-US are useful tools in clarifying the nature of breast lesions in cases with doubtful mammography. The clinical value of these diagnostic procedures in guiding subsequent therapeutic interventions requires further investigation.

Contribution of 99mTc-anti-carcinoembryonic antigen antibody and 99mTc-sestamibi scintimammography in the evaluation of high risk palpable breast lesions.

Mammography is the screening test of choice for breast cancer. Its low specificity leads to a large number of unnecessary biopsies. Scintimammography, with either Tc-sestamibi (MIBI) or Tc-anti-carcinoembryonic antigen (CEA) Fab', has been proposed as a non-invasive test to lower the high false positive rate of mammography in certain patients. The two agents have not been compared, nor has their combined application been evaluated. We performed a prospective, non-randomized, open-label, single-centre study of 32 women with clinically and mammographically suspected breast cancer [Breast Imaging Reporting and Data System (BI-RADS, American College of Radiology) 4 or 5]. All patients underwent Tc-MIBI and Tc-anti-CEA Fab' scintimammography, and the results were correlated with histopathology. Overall, the accuracies for MIBI and CEA scans were 90.3% (28/31) and 77.4% (24/31), respectively. The probability of disease after mammography was 0.939+/-0.081 (95% confidence interval, CI). The post-mammography probabilities after positive MIBI or CEA scan were 0.965 and 0.960, respectively, and after negative MIBI or CEA scan 0.750 and 0.875, respectively. None of the above differences is significant. The post-test probability when both scans were positive (irrespective of which was performed first) was 0.977. It can be concluded that there are indications that scintimammography with Tc-MIBI is superior to that with Tc-anti-CEA Fab' when these tests are used as screening tests for breast cancer. However, mammography remains the screening test of choice for highly suspicious clinically palpable breast lesions. In this group of patients, the application of scintimammography with either Tc-MIBI or Tc-anti-CEA Fab' (alone or in combination) offers no additional advantage.

High intratumoral accumulation of stealth liposomal doxorubicin in sarcomas--rationale for combination with radiotherapy.

Sarcomas are radioresistant tumors, the only curative therapy being radical surgical resection. Stealth liposomal doxorubicin (Caelyx) is a novel drug formulation that allows prolonged circulation and high intratumoral concentration. This study investigates the concurrent use of radiotherapy with Caelyx in a cohort of 7 patients with locally advanced or recurrent sarcoma. Radiotherapy was given as a standard fractionation regimen to a total dose of 70 Gy. Caelyx was given as a 30-min infusion at a dose of 25 mg/m2 every 2 weeks. Scintigraphic imaging with Caelyx-99mTc-DTPA showed an increased (2.8 +/- 0.9 times higher) intratumoral drug accumulation compared to the surrounding healthy tissue. The regimen was well tolerated without any severe hematological or systemic toxicity. 'In field' radiation toxicity was not increased. Complete response was observed in 4/7 cases. It is concluded that combined chemo-radiotherapy with stealth liposomal doxorubicin for locally advanced sarcomas is feasible and promising, the benefit expected from the unique ability of the stealth liposomes to accumulate selectively in the tumoral tissue.

Assessment of myocardial adrenergic innervation in patients with sick sinus syndrome: effect of asynchronous ventricular activation from ventricular apical stimulation.

OBJECTIVE: To investigate ventricular sympathetic innervation in patients with sick sinus syndrome and to detect regional deterioration of adrenergic innervation caused by asynchronous ventricular activation from right ventricular pacing. DESIGN: Prospective controlled study. SETTING: Tertiary cardiac referral centre. PATIENTS: 22 patients with sick sinus syndrome and indications for permanent dual chamber pacing; 20 healthy individuals as controls. INTERVENTIONS: All patients underwent myocardial imaging with planar and single photon emission computed tomography (SPECT) after an intravenous infusion of 5 mCi 123I-meta-iodobenzylguanidine (123I-MIBG) before and after pacemaker implantation. A SPECT thallium201 myocardial study was done during the same week as the 123I-MIBG study in all patients. MAIN OUTCOME MEASURES: The heart to mediastinum (H/M) ratio and washout rate were calculated during the 123I-MIBG study to assess the global cardiac sympathetic activity; the aim of the SPECT study was to investigate the regional distribution of adrenergic innervation. RESULTS: The H/M ratio was significantly smaller in the patients with sick sinus syndrome than in the controls (p < 0.001). In sick sinus syndrome there were regional adrenergic innervation defects, mostly in the inferior and apical walls. After a medium term pacing period, a redistribution of 123I-MIBG uptake was detected, with deterioration of adrenergic innervation in the inferior, apical, and posterior walls. The thallium201 myocardial perfusion study showed no change after three months of permanent pacing. CONCLUSIONS: Patients with sick sinus syndrome have global and regional disturbances of the adrenergic innervation of the left ventricular myocardium. These seem to deteriorate as a result of asynchronous electrical activation. The clinical significance of this finding requires further investigation.