['Sentinel lymph node biopsy (SLNB) before mastectomy and immediate breast reconstruction (IBR) may help to avoid the negative cosmetic effects of radiotherapy on reconstructed breasts in lymph node-positive patients. Concerns have been raised regarding possible delays whilst awaiting the SLNB result prior to definitive surgery, which needs to be performed within 31 days of cancer diagnosis. The aim was to investigate whether initial SLNB delays mastectomy and IBR.', 'All patients who had IBR between January 2005 and 2007 were reviewed retrospectively. Before October 2005 axillary staging was performed simultaneously with mastectomy and IBR (Group I). After October 2005, SLNB was performed as an initial procedure and patients with positive SLNB were only offered a temporary tissue expander to be replaced by autogenous reconstruction after completing the cancer treatment (Group II). Date of diagnosis and waiting times were recorded and the two groups were compared. Different reasons for delays in treatment were studied.', 'One hundred and thirty-nine IBR (123 patients) were included in the statistical analysis (67 IBR in Group I and 72 IBR in Group II). Seventy-one patients (57.7%) had no delay (mean waiting time of 23 days). Fifty-two patients (42.3%) had delay longer than 31 days (mean waiting time of 66 days). Group I patients had a mean waiting time (standard deviation) of 38.8 (38) days and Group II patients 42.7 (24) days (p = 0.51).'] Does sentinel lymph node biopsy before mastectomy and immediate breast reconstruction significantly delay surgery in early breast cancer?