TABLE 1.
Tissue reactions from single‐delivery radiation dose to skin of the neck, torse, pelvis, buttocks, or arms
| Single‐site | ||||||
|---|---|---|---|---|---|---|
| acute skin | NCI skin | |||||
| dose range | reaction | Approximate time of onset of effects | ||||
| Band | (Gy) a | grade | Prompt | Early | Midterm | Long term |
| A1 | 0–2 | NA | No observable effects expected | No observable effects expected | No observable effects expected | No observable effects expected |
| A2 | 2–5 | 1 | Transient erythema | Epilation | Recovery from hair loss | No observable results expected |
| B | 5–10 | 1–2 | Transient erythema | Erythema, epilation | Recovery; at higher doses, prolonged erythema; permanent partial epilation | Recovery; at higher doses, dermal atrophy or induration |
| C | 10–15 | 2–3 | Transient erythema | Erythema, epilation; possible dry or moist desquamation; recovery from desquamation | Prolonged erythema; permanent epilation | Telangiectasia b ; or induration; skin likely to be weak |
| D | >15 | 3–4 | Transient erythema; after very high doses, edema and acute ulceration; long‐term surgical intervention likely to be required | Erythema, epilation; moist desquamation | Dermal atrophy; secondary ulceration due to failure of moist desquamation to heal; surgical intervention likely to be required; at higher doses, dermal necrosis, surgical intervention likely to be required | Telangiectasia b ; dermal atrophy or induration; possible late skin breakdown; wound might be persistent and progress into a deeper lesion; surgical intervention likely to be required |
Note: Applicable to normal range of patient radiosensitivities in absence of mitigating or aggravating physical or clinical factors. Data do not apply to the skin or the scalp. Dose and time bands are not rigid boundaries. Signs and symptoms are expected to appear earlier as skin dose increases. Prompt, <2 weeks; early, 2–8 weeks; midterm, 6–52 weeks; long term, >40 weeks.
Abbreviations: NA, not applicable; NCI, National Cancer Institute.
Skin dose referes to actual skin dose (including backscatter). This quantity is not the reference point air kerma described by Food and Drug Administration (21 CFR § 1020.32 [2008]) or International Electrotechnical Commission. Skin dosimetry is unlikely to be more accurate than ±50%.
Refers to radiation‐induced telangiectasia. Telangiectasia associated with area of initial moist desquamation or healing of ulceration may be present earlier.
Source: Reproduced from Balter et al., 11 Tissue reactions from radiation doses to the skin.