Positive predictive value of 99mTc sestamibi scintimammography in patients with non-palpable, mammographically detected, suspicious, breast lesions

Abstract

The purpose of this study was to analyse whether the use of Tc sestamibi scintimammography improves the positive predictive value of X-ray mammography. A series of 73 women (median age 51 years, range 35-79 years) with non-palpable, mammographically suspicious, breast lesions was reviewed. There were 41 (56.2%) pre-menopausal, and 32 (43.8%) post-menopausal women. All patients underwent sestamibi scintimammography prior to open breast biopsy. Definitive histology showed breast cancer (pT1a=1 (1.9%), pT1b=47 (90.4%), pT1c=4 (7.7%)) in 52 (71.2%) patients, and benign breast lesions in 21 (28.8%). Patients with cancer were significantly older (P<0.01), while the greatest dimension (size) of the excised lesion did not differ (8.47+/-1.51 vs 8.30+/-1.53 mm; P =0.66) between the two groups. Overall, the positive predictive values of mammography and sestamibi scintimammography were 71.2% and 95.7%, respectively (P =0.004). Patients with false positive mammography were significantly younger than those in whom cancer was diagnosed correctly (45.35+/-7.56 vs 53.96+/-10.60 years; P =0.001), while age did not affect the sensitivity of sestamibi scintimammography, which reached 100% in patients with breast lesions > or =8 mm in size. In this subgroup the positive predictive value of mammography, sestamibi scintimammography, and mammography+sestamibi scintimammography together were 63.4%, 95.1% (P =0.001), and 97.6%, respectively, and the majority of the patients with benign lesions (13 of 15 (86.7%)) could have avoided biopsy. It is concluded that the use of Tc sestamibi scintimammography in conjunction with mammography may potentially reduce unnecessary surgical procedures, and should be performed in all patients with mammographically suspicious breast lesions of 8 mm or greater in size.

Usefulness of scintimammography as an adjunct to mammography and ultrasound in the diagnosis of breast diseases

“…[5][6][7][8] The aim of this prospective study was to evaluate the diagnostic efficacy of SM compared with the combined use of mammography and ultrasound in a group of patients with symptomatic breast having lumps or pain. …”

“…Because the diagnostic accuracy of SM is independent of the density of breast parenchyma, the technique plays an adjunctive role in the differentiation of benign from malignant lesions. [5][6][7][8] The aim of this prospective study was to evaluate the diagnostic efficacy of SM compared with the combined use of mammography and ultrasound in a group of patients with symptomatic breast having lumps or pain.…”

99mTc-thymine scintigraphy may be a promising method in the diagnosis of breast cancer

“…Despite promising initial results, breast scintigraphy with 99mTc-sestamibi is not yet included in the routine diagnosis of breast cancer. The sensitivity of the method was reported to range from 84 to 96% in initial studies, and the specificity ranged from 86 to 100% (13,26,27). However, in more recent publications, particularly in multicenter studies in which a large number of palpable and impalpable lesions were studied, sensitivity and specificity were both reduced (28-30).…”

“…In the last decade, progress in pharmacology combined with evolving technology has enabled the establishment of scintimammography as a non-invasive technique for the localization and staging of malignant tumors of the breast using molecules such as Sestamibi and Tetrofosmin labeled with technetium-99m (99mTc) (13-15). Other molecules such as 99mTc(V) dimercaptosuccinic acid (DMSA) and 99mTc-labeled alkyl triphenyl phosphonium (99mTc-Mito 10 -MAG3) are also being studied to improve detection (16,17).…”

“…Breast scintigraphy has a major indication for select groups of patients with dense breasts; patients using hormone therapy; patients suspected of having recurrent disease resulting in architectural distortions secondary to previous surgery; patients undergoing chemotherapy or radiotherapy or who have breast implants; and patients at high risk for breast cancer (15,18-21). Scintimammography is also useful for the study of breast cancer multicentricity (13,15). …”