Invited commentary

Axillary staging in women with small invasive breast tumours

AIMS

To identify a group of women with small breast cancers of favourable histological grade for whom observation alone may be an acceptable approach for management of the axilla.

METHODS

In a retrospective analysis the incidence of nodal metastases was examined in a group of 355 consecutive patients over 55 years of age who underwent mastectomy or breast conserving surgery. All patients had either grade I (<20 mm) or grade II (<15 mm) oestrogen receptor positive tumours without lymphovascular invasion (LVI). In a related study on 173 clinically node negative patients, the rate of axillary recurrence was assessed in patients with small (<10 mm), non-high grade (I and II), ER-positive invasive ductal carcinomas without LVI. Axillary surgery was either omitted (135 patients) or delayed (38 patients) at the time of wide local excision or mastectomy.

RESULTS

The overall incidence of positive nodes in this good prognostic group of patients was 13% (95% confidence interval 9.5-16.5). When the analysis was confined to grade I (< or =20 mm) and grade II (< or =10 mm) the overall incidence of nodal metastases was 10%. Rates of axillary recurrence at a median follow up of 49 months were only 1% when axillary surgery was omitted according to patient choice/departmental policy with no cases of uncontrolled axillary recurrence.

CONCLUSION

The risk:benefit ratio for detection of node positive cases in a selected group of older patients does not justify any form of axillary procedure at the time of primary surgery.

Clinical and pathological factors predictive of lymph node status in women with screen-detected breast cancer

Two thousand one hundred and thirty five asymptomatic invasive breast cancers detected through screening mammography were analysed to identify predictors of lymph node involvement. Multivariable analysis indicated that predictors included larger tumour diameter, an infiltrating ductal or lobular histological type, multifocal disease, a palpable lesion, and a younger age at diagnosis. An association also was found between nodal involvement and the presence of an extensive in situ component (EIC). Grade was associated with nodal involvement as a univariate predictor. It would be more accurate for screening assessment clinics to use models for predicting nodal status that were customised to their own experience rather than generic models developed in other settings that related predominantly to symptomatic cancer. These models could assist clinical decision-making on axillary node dissection and give guidance to pathologists on numbers of tissue sections to examine.