It is likely your oncologist will recommend radiaition. Since your are HER2 positive, heceptin infusions will be likely as well as either Tamoxifen or an aromatase inhibitor since your are ER positive as well. Whether your doctor recommends general chemo as well, depends on a number of factors.
The first time I had breast cancer, I had a lumpectomy, radiation, and 5 years of Tamoxifen. The second time I had breast cancer, I had chemotherapy, herceptin, bilateral mastectomy, radiation, and am currently on an aromatase inhibitor for at least 5 years.