Does HER2 status influence locoregional failure rates in breast cancer patients treated with mastectomy for pT1-2pN0 disease?
BACKGROUND
The impact of HER2 overexpression on the locoregional control of breast cancer is controversial.


METHODS
Data on 906 women diagnosed with pT(1-2)pN(0) breast cancer from 1986 to 1992 with known HER2 status and treated with a modified radical mastectomy without adjuvant radiotherapy or adjuvant trastuzumab were analyzed with respect to local relapse-free survival (LRFS), regional relapse-free survival (RRFS) and distant relapse-free survival (DRFS). Log-rank statistics were used to compare 10-year Kaplan-Meier curves of LRFS, RRFS and DRFS in HER2+ and HER2- patients.


RESULTS
Median follow-up was 12.8 years. HER2+ patients had a worse DRFS (P = 0.028) but there was no statistically significant difference in LRFS or RRFS between HER2+ and HER2- patients (P = 0.32 and 0.24 for LRFS and RRFS, respectively). Ten-year LRFS estimates among HER2+ patients was 91.3% and 86.9% for HER2- patients. Ten-year RRFS estimates for HER2+ and HER2- patients were 88.0% and 93.0%, respectively.


CONCLUSIONS
HER2 overexpression was not associated with higher local or regional recurrence risk in subjects with pT(1-2)pN(0) breast cancer following mastectomy and nodal dissection after a median follow-up of >12 years.
Kwan
W
W
Radiation Therapy Program, Fraser Valley Centre, British Columbia, Canada. wkwan@bccancer.bc.ca
Al-Tourah
A J
AJ
Speers
C
C
Woods
R
R
Kennecke
H
H
Olivotto
I A
IA
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D015411:Mastectomy, Modified Radical; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000473:pathology / Q000601:surgery*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D015996:Survival Rate; D016896:Treatment Outcome
D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; C508053:ERBB2 protein, human