Impact of screening on clinicopathological features and treatment for invasive breast cancer: Results of two national surveys

Abstract Purpose Several studies showed a breast cancer downstaging due to screening. A first national survey was conducted in France in 2001–2002 to evaluate in the current clinical practice the clinicopathological features and treatments of 1049 firstly operated breast cancers. In order to assess the impact of the national screening program implemented in all regions in France in 2004, a new survey was performed in 2007–2008. Material The new survey included 1433 firstly operated breast cancers prospectively collected. These new data were compared to the results of the first national survey. Results According to TN classification, we found in the second survey T 0 : 27.6%, T 1 : 48.6%, T 2 : 21.3%, T 3 T 4 : 3.8% and T x : 0.7%. Infiltrating ductal and lobular carcinomas represented 80% and 13% of tumours. Hormone receptors were positive in 85.3% and Her-2 overexpressed in 12.4% of tumours (83.9% and 20.6% in the first survey); 68.2% and 32% were pN 0 and pN 1-3 . Lumpectomy and mastectomy were performed in 77% and 23% of the cases. Axillary dissection, sentinel node biopsy or both were performed in 42.6%, 41% and 16.4% of the cases, respectively. Radiotherapy, chemotherapy, hormonotherapy and trastuzumab were given to 93%, 51%, 83% and 9.3% of the patients. Compared with the results from the first survey, we found an increase of infraclinical lesions (T 0 from 8.4 to 27.6%) and a wide decrease of pN+ rate (from 44% to 32%). The mastectomy rate was constant (23%), as well as radiotherapy use, whereas chemotherapy use decreased from 62.8 to 55.6%. Conclusion A complete national screening coverage clearly provides a favourable modification of breast cancer clinicopathological features. Both locoregional and adjuvant treatments were greatly downscaled.