Predictors of sentinel lymph node metastases in breast cancer-radioactivity and Ki-67.
OBJECTIVE
Since the introduction of the sentinel node technique for breast cancer in the 1990s patient's morbidity was reduced. Tracer uptake is known to be dependent from lymph node integrity and activity of macrophages. The aim of this study was to assess whether radioactivity of the tracer can predict sentinel lymph node metastases. Furthermore, a potential association with Ki-67 index was examined. Non-invasive prediction of lymph node metastases could lead to a further decrease of morbidity.


METHODS
We retrospectively analyzed patients with primary breast cancer who underwent surgery at the Department of Obstetrics and Gynecology in the University Hospital of Cologne between 2012 and 2013. Injection of radioactive tracer was done a day before surgery in the department of Nuclear Medicine. Clinical data and radioactivity of the sentinel node measured the day before and intraoperatively were abstracted from patient's files.


RESULTS
Of 246 patients, 64 patients had at least one, five patients had two and one patient had three positive sentinel lymph nodes. Occurrence of sentinel lymph node metastases was not associated with preoperative tracer activity (p = 0,319), intraoperative tracer activity of first sentinel node (p = 0,086) or with loss of tracer activity until operation (p = 0,909). There was no correlation between preoperative Ki-67 index and occurrence of lymph node metastases (p = 0,403).


CONCLUSIONS
In our cohort, there was no correlation between radioactivity and sentinel node metastases. Tracer uptake might not only be influenced by lymph node metastases and does not predict metastatic lymph node involvement.
Department of Gynecology and Obstetrics, University Hospital of Cologne, Kerpener Straße 34, 50931 Cologne, Germany. Electronic address: Fabinshy.Thangarajah@uk-koeln.de.
Fabinshy
F
Thangarajah
Breast Center, Kliniken Essen-Mitte, Henricistraße 92, 45136 Essen, Germany; Breast Center, University Hospital of Cologne, Kerpener Straße 34, 50931 Cologne, Germany.
Wolfram
W
Malter
Department of Medical Statistics, Informatics and Epidemiology, University of Cologne, Kerpener Straße. 62, 50937 Cologne, Germany.
Stefanie
S
Hamacher
Department of Nuclear Medicine, University Hospital of Cologne, Kerpener Straße 62, 50937 Cologne, Germany.
Matthias
M
Schmidt
Breast Center, University Hospital of Cologne, Kerpener Straße 34, 50931 Cologne, Germany.
Stefan
S
Krämer
Department of Gynecology and Obstetrics, University Hospital of Cologne, Kerpener Straße 34, 50931 Cologne, Germany.
Peter
P
Mallmann
Department of Gynecology and Obstetrics, University Hospital of Cologne, Kerpener Straße 34, 50931 Cologne, Germany.
Verena
V
Kirn
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008408:Mastectomy; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009367:Neoplasm Staging; D011849:Radioactive Tracers; D011851:Radioactivity; D019275:Radiopharmaceuticals / Q000378:metabolism*; D012189:Retrospective Studies; D000071036:Sentinel Lymph Node / Q000473:pathology*; D021701:Sentinel Lymph Node Biopsy; D013668:Technetium Tc 99m Aggregated Albumin / Q000378:metabolism*
D019394:Ki-67 Antigen; D011849:Radioactive Tracers; D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin
Ki-67 index; Lymph node metastases; Predictive factors; Radioactivity; Sentinel node biopsy