Radioactive seed localization in breast cancer treatment.
BACKGROUND
Breast cancer screening, improved imaging and neoadjuvant systemic therapy (NST) have led to increased numbers of non-palpable tumours suitable for breast-conserving surgery (BCS). Accurate tumour localization is essential to achieve a complete resection in these patients. This study evaluated the role of radioactive seed localization (RSL) in improving breast- and axilla-conserving surgery in patients with breast cancer with or without NST.


METHODS
Patients who underwent RSL between 2007 and 2014 were included. Learning curves were analysed by the rates of minimally involved (in situ/invasive tumour cells on a length of 0-4 mm on ink) and positive resection margins (over 4 mm on ink) after BCS, and the median resection volume over time.


RESULTS
A total of 367 patients with in situ carcinomas and 199 with non-palpable invasive breast cancer underwent RSL before primary surgery. A further 697 patients had RSL before NST, of whom 206 also underwent RSL of a histologically verified axillary lymph node metastasis. BCS was performed in 93·2 and 87·9 per cent of patients undergoing primary surgery for in situ and invasive tumours respectively, and 57·5 per cent of those in the NST group. The rate of BCS with positive resection margins was low and stable over time in the three groups (9·1, 9·7 and 11·2 per cent respectively). The median resection volume decreased significantly with time in the invasive cancer and NST groups.


CONCLUSIONS
In the present study of more than 1200 patients and 7 years of experience, RSL was shown to facilitate breast- and axilla-conserving surgery in a diverse patient population. There was a significant reduction in resection volume while maintaining low positive resection margin rates after BCS.
Departments of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands.
N N Y
NN
Janssen
Departments of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands.|Departments of Surgery, Netherlands Cancer Institute, Amsterdam, The Netherlands.
J
J
Nijkamp
Department of Radiation Oncology, Academic Medical Centre, Amsterdam, The Netherlands.
T
T
Alderliesten
Departments of Radiology, Netherlands Cancer Institute, Amsterdam, The Netherlands.
C E
CE
Loo
Departments of Surgery, Netherlands Cancer Institute, Amsterdam, The Netherlands.
E J T
EJ
Rutgers
Departments of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands.
J-J
JJ
Sonke
Departments of Surgery, Netherlands Cancer Institute, Amsterdam, The Netherlands.
M T F D
MT
Vrancken Peeters
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery / Q000628:therapy; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging* / Q000601:surgery / Q000628:therapy; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging* / Q000601:surgery / Q000628:therapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D059032:Learning Curve; D016014:Linear Models; D015412:Mastectomy, Segmental; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D016896:Treatment Outcome
D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals