title: Effect of increased (99m)Tc/(99)Tc ratios on count rates in sentinel node procedures: a randomised study.
abstract: The aim of this study was to evaluate the count rates of sentinel lymph nodes (SLNs) in patients with breast cancer in the operating theatre, using (99m)Tc-Nanocoll with different ratios of technetium-99m to technetium-99. After written informed consent had been obtained, we tested different ratios of (99m)Tc/(99)Tc-Nanocoll in a double-blinded randomised study performed in 161 patients. Twenty-five MBq/ microg (99m)Tc-colloid albumin was prepared in vacuum. In 87 patients (group A) a 2-h elution was used and in 74 patients (group B) a 24-h elution was used. Patients were subcategorised into subgroups 1 and 3, in which an SLN procedure for breast carcinoma was performed simultaneously with lumpectomy, and subgroups 2 and 4, in which an SLN procedure was performed 2-3 weeks after prior excision biopsy. All patients were injected along the lateral border of the areola (two injections: 50 MBq/0.3 ml intradermally and 50 MBq/2 ml intraparenchymally). Ex vivo measurement of count rates was performed with a gamma probe. Comparing groups A and B in respect of registered counts per second (cps) of excised SLNs, a significant difference was found ( P<0.004). When comparisons were made between subgroups 1 and 2 (2-h elution) and between subgroups 3 and 4 (24-h elution) in respect of registered cps of excised SLNs, no significant difference was found (subgroup 1 vs 2, P=0.825; subgroup 3 vs 4, P=0.915). Use of a 2-h elution in vacuum yielded a significantly higher count rate of maximum specific activity of (99m)Tc-colloid albumin in SLNs than was achieved using a 24-h elution in vacuum. SLN procedures performed 2-3 weeks after prior excision biopsy proved reliable as compared to SLN procedures performed simultaneously with lumpectomy.
authors.affiliation: Department of Nuclear Medicine, Westfries Gasthuis Hoorn, 1620 AR Hoorn, The Netherlands. g.m.m.gommans@wfg.nl
authors.forename: G M M
authors.initials: GM
authors.lastname: Gommans
authors.forename: F M
authors.initials: FM
authors.lastname: van der Zant
authors.forename: T G
authors.initials: TG
authors.lastname: van der Schors
authors.forename: A
authors.initials: A
authors.lastname: van Dongen
authors.forename: G J J
authors.initials: GJ
authors.lastname: Teule
authors.forename: W W J
authors.initials: WW
authors.lastname: Clarijs
authors.forename: B L A M
authors.initials: BL
authors.lastname: Langenhorst
authors.forename: J W D
authors.initials: JW
authors.lastname: de Waard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D003951:Diagnostic Errors; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007267:Injections / Q000379:methods*; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011874:Radiometry / Q000379:methods; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013668:Technetium Tc 99m Aggregated Albumin / Q000008:administration & dosage*
chemical_list: D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; C083602:technetium Tc 99m nanocolloid