| Body site |
| Anterior of neck |
| Extremities |
| Chest/breast |
| Abdomen |
| Face |
| Scalp (hair follicles) |
| Patient-related factors |
| Obesity |
| Age (older) |
| Sex (female) |
| Chronic sun exposure |
| Smoking |
| Breast reconstruction/implants |
| Pre-existing disorders |
| Connective tissue disorders (scleroderma) |
| Radiosensitivity disorders (ataxia telangiectasia) |
| Drug-induced radiation recall |
| Anthracyclines (doxorubicin) |
| Taxanes (docetaxel, paclitaxel) |
| Antimetabolites (gemcitabine, capecitabine) |
| Antibiotics |
| Antituberculosis medications |
| Simvastatin |
