1. ¹Comprehensive Cancer Center North-Netherlands, PO Box 330, 9700 AH Groningen, The Netherlands
2. ²Department of Medical Oncology, University Medical Center Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands
3. ³Department of Surgical Oncology, University Medical Center Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands
4. ⁴Department of Radiotherapy, University Medical Center Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands
5. ⁵Department of Medical Oncology, University Medical Center Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands

Correspondence: M Schaapveld, E-mail: m.schaapveld@ikn.nl

Received 14 February 2005; Revised 20 July 2005; Accepted 21 July 2005; Published online 23 August 2005.

Abstract

This population-based study aimed to analyse variations in surgical treatment and guideline compliance with respect to the application of radiotherapy and axillary lymph node dissection (ALND), for early breast cancer, before and after the sentinel node biopsy (SNB) introduction. The study included 13 532 consecutive surgically treated stage I–IIIA breast cancer patients diagnosed in 1989–2002. Hospitals showed large variation in breast-conserving surgery (BCS) rates, ranging between 27 and 72% for T1 and 14 and 42% for T2 tumours. In multivariate analysis marked inter-hospital and time-dependent variation in the BCS rate remained after correction for case-mix. The guideline adherence was markedly lower for elderly patients. In 25.2% of the patients aged 75 years either ALND or radiotherapy were omitted. The proportion of patients with no ALND after an SNB increased from 1.8% in 1999 to 37.8% in 2002. However, in 2002 also 12.2% of the patients with a positive SNB did not have an ALND. Guideline compliance for BCS, with respect to radiotherapy and ALND, fell since the SNB introduction, from 96.1% before 2000 to 91.4% in 2002 (P<0.001). Noncompliance may however reflect patient-tailored medicine, as for elderly patients with small, radically resected primary tumours. The considerable variation in BCS-rates is more consistent with variations in surgeon preferences than patient's choice.