Although a beneficial adjunct for breast cancer in several circumstances, radiation therapy (RT) has also detriments to both the patient as well as plastic surgeon in breast reconstruction. Above all, treatment for cancer comes before the aesthetics of breast reconstruction, and the proven benefit outweighs the ill-effects of RT. The impact that RT has on the skin, as evidenced by the radiation dermatitis/radiation burn, angiofibrosis, contrcture/fibrosis of the skin, and soft tissue, as well as the healing/infection issues are not favorable.
From the plastic surgery standpoint, these effects are troublesome, especially when dealing with reconstruction. This should be discussed with your plastic surgeon, as it impacts the type of reconstruction you should have. Women undergoing lumpectomy are often told that most of their breast will be preserved and that radiation will be needed postoperatively. However, what is not conveyed, is that the above changes may occur and account for some of the breast asymmetry or contractures. Although a "breast conserving" therapy is performed, many women end up seeking a plastic surgeon to assist with these issues, which often times, include the same procedures as if a mastectomy was performed anyhow.
Implant-based reconstruction is not a recommended reconstructive procedure following RT. The complication rates are markedly increased with often times, poor aesthetic results, let alone the wound healing, infection, and capsular contracture/asymmetry rates, among others. This type of reconstruction usually fairs poorly following RT. There are several studies showing good results following implant-based reconstruction, however. Many times, RT is not known until final pathology returns several days later.
Radiation after flap-based procedures are significantly better following RT. After a flap procedure (e.g., latissismus, TRAM, or DIEP flap, recruiting well-vascularized tissue from a remote area negates some of the ill-effects that RT has done. There still is a chance for the reconstructed breast to shrink or contract if followed by radiation, but it resists the effects much better than implants. Usually, performing this in a delayed fashion would allow your plastic surgeon to excise all of the affected tissue, and use the flap to reconstruct the defect. This is my preference after, or for known RT. The flap-based reconstructions (e.g., latissimus, TRAM, or notably the DIEP), are excellent options as discussed in previous posts.