Breast Cancer - sentinel node has "isolated tumor cells" after chemo & lumpectomy

Hi all,

I have breast cancel and i have finished chemo and had a lumpectomy.  I have just got the results of surgery and the sentinal lymph node has "isolated tumor cells" .  I have been given the option between an auxilary clearance of the lumph nodes (only 4 were taken at surgery) or extend the area of radiotherapy - the consultants strong recommendation is that a clearance is unnecessary and that extended radiotheraphy will achieve the same effect.  This will be the mmaximum radiotherapy that can be given.

Would it be possible to get a link to mainstream information that can help me understand how the risk of reoccurance is the same under both options?

Kind regards

Dianne