A systematic review of axillary nodal irradiation for the management of the axilla in patients with early-stage breast cancer.

BACKGROUND: Given numerous publications and clinical trials regarding axillary management in breast cancer, we sought to summarize this complex literature to help clarify this field for clinicians. This systematic review focuses on the role of irradiation of the axillary nodes (locoregional nodal irradiation [LRNI]) in the management of the axilla in patients with early-stage breast cancer in various clinical settings. METHODS: We searched MEDLINE and EMBASE databases, the Cochrane library, the proceedings of the ASCO, the ASTRO, the ESMO, the ESTRO, and the San Antonio Breast Cancer Symposium (2016-2019) meetings. The quality of the studies was assessed with design-specific tools. The study was registered in PROSPERO. RESULTS: We included one systematic review, one individual patient data (IPD) meta-analysis, and five randomized controlled trials (RCTs). After axillary lymph node dissection (ALND), LRNI resulted in small benefits in breast cancer specific mortality, locoregional recurrence, and distant metastases-free survival but not overall survival. After a positive sentinel node biopsy (SLNB), LRNI may provide equivalent locoregional control and disease-free survival (DFS) compared to ALND with a lower risk of lymphedema. No randomized data is available for the neoadjuvant setting. CONCLUSIONS: The summary of the role of radiation, is relevant to radiation oncologists for choosing the correct cohort of patient requiring LRNI and to surgeons making clinical decisions regarding the timing and type of breast reconstruction offered to patients.

Measurement of recombinase activity in a set of related Abelson murine leukemic virus pre-B cell lines: DJ/DJ lines have more recombinase activity than do VDJ/VDJ lines.

The VDJ recombination potential of a number of Abelson murine leukemic virus transformed fetal liver cell lines derived from (C57BL/6 x BALB/c) F1 mice was measured. The specific developmental stage of each line was determined using Southern blot analysis to ascertain their rearrangement status at the immunoglobulin heavy chain locus (DJ/DJ, VDJ/DJ or VDJ/VDJ). It was observed that DNA from DJ/DJ lines gave many more 'subhaploid' bands hybridizing with JH than did DNA from VDJ/VDJ lines. While the lack of appropriate substrate (VDJ/VDJ lines have exhausted the normal IgH substrate) contributes to the decrease in 'subhaploid bands', this result indicates that the rate of ongoing immunoglobulin heavy chain gene rearrangement was higher in the DJ/DJ lines. However, when the lines were examined using the assay developed by Hesse et al. (4) to measure VDJ recombinase activity, it was found that although all lines had recombinase activity, the DJ/DJ lines had four times more VDJ recombinase activity than did the VDJ/VDJ lines.