Sentinel lymph node biopsy can be omitted in DCIS patients treated with breast conserving therapy.

Breast cancer guidelines advise sentinel lymph node biopsy (SLNB) in patients with ductal carcinoma in situ (DCIS) on core biopsy at high risk of invasive cancer or in case of mastectomy. This study investigates the incidence of SLNB and SLN metastases and the relevance of indications in guidelines and literature to perform SLNB in order to validate whether SLNB is justified in patients with DCIS on core biopsy in current era. Clinically node negative patients diagnosed from 2004 to 2013 with only DCIS on core needle biopsy were selected from a national database. Incidence of SLN biopsy and metastases was calculated. With Fisher exact tests correlation between SLNB indications and actual presence of SLN metastases was studied. Further, underestimation rate for invasive cancer and correlation with SLN metastases was analysed. 910 patients were included. SLNB was performed in 471 patients (51.8 %): 94.5 % had pN0, 3.0 % pN1mi and 2.5 % pN1. Patients undergoing mastectomy had 7 % SLN metastases versus 3.5 % for breast conserving surgery (BCS) (p = 0.107). The only factors correlating to SLN metastases were smaller core needle size (p = 0.01) and invasive cancer (p < 0.001). Invasive cancer was detected in 16.7 % by histopathology with 15.6 % SLN metastases versus only 2 % in pure DCIS. SLNB showed metastases in 5.5 % of patients; 3.5 % in case of BCS (any histopathology) and 2 % when pure DCIS was found at definitive histopathology (BCS and mastectomy). Consequently, SLNB should no longer be performed in patients diagnosed with DCIS on core biopsy undergoing BCS. If definitive histopathology shows invasive cancer, SLNB can still be considered after initial surgery.

Derivation of human embryonic stem cell lines from embryos obtained after IVF and after PGD for monogenic disorders.

BACKGROUND: Human embryonic stem (hES) cells are pluripotent cells usually derived from the inner cell mass (ICM) of blastocysts. Because of their ability to differentiate into all three embryonic germ layers, hES cells represent an important material for studying developmental biology and cell replacement therapy. hES cell lines derived from blastocysts diagnosed as carrying a genetic disorder after PGD represent in vitro disease models. METHODS: ICMs isolated by immunosurgery from human blastocysts donated for research after IVF cycles and after PGD were plated in serum-free medium (except VUB01) on mouse feeder layers. RESULTS: Five hES cell lines were isolated, two from IVF embryos and three from PGD embryos. All lines behave similarly in culture and present a normal karyotype. The lines express all the markers considered characteristic of undifferentiated hES cells and were proven to be pluripotent both in vitro and in vivo (ongoing for VUB05_HD). CONCLUSIONS: We report here on the derivation of two hES cell lines presumed to be genetically normal (VUB01 and VUB02) and three hES cell lines carrying mutations for myotonic dystrophy type 1 (VUB03_DM1), cystic fibrosis (VUB04_CF) and Huntington disease (VUB05_HD).