Prediction of lymph node status by analysis of prognostic factors and possible indications for elective axillary dissection in T1 breast cancers.
OBJECTIVE
To identify those patients with T1 breast cancers with lower risk of nodal metastases who can safely be spared axillary dissection.


METHODS
Retrospective study.


METHODS
University hospital, Italy.


METHODS
Review of clinical records and histopathological slides of 547 patients with T1 breast cancer, operated on between 1984 and 1997.


METHODS
Incidence of axillary metastases in relation to age, menopausal status, diameter and grade of tumour, vascular invasion, DNA ploidy, S-phase fraction and hormone receptor state, by univariate and multivariate analysis.


RESULTS
Axillary metastases were present in 159 patients (29%). On univariate analysis, diameter of tumour 10 mm or less (pT1a/pT1b cancers), no vascular invasion, and grade 1 tumour were significantly correlated with a lower risk of nodal metastases, but only vascular invasion (p = 0.0001, odds ratio = 3.1) and diameter of tumour (p = 0.04, odds ratio = 1.6) were independent predictors on multivariate analysis. Among 34 pT1a/pT1b cancers, with low grade of tumour and no vascular invasion, only 2 (6%) had axillary metastases. When only one favourable predictive factor was associated with diameter of tumour of 10 mm or less, the incidence of axillary metastases ranged from 12% for 43 patients with grade 1 cancers to 13% for 76 patients with no vascular invasion.


CONCLUSIONS
Axillary dissection may be avoided in pT1a and pT1b breast cancers (< or = 10 mm), with low grade of tumour or no vascular invasion. T1 breast cancers 10 mm or less in diameter should be treated by a two-step approach, first wide excision of the tumour and then axillary dissection or not depending on pathological examination of the primary tumour.
Guarnieri
A
A
Institute of Surgical Sciences, University of Siena, Italy.
Neri
A
A
Correale
P P
PP
Lottini
M
M
Testa
M
M
Mariani
F
F
Tucci
E
E
Megha
T
T
Cintorino
M
M
Carli
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001365:Axilla; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D017558:Elective Surgical Procedures; D005260:Female; D006801:Humans; D015994:Incidence; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies