Table 3. Risk of SPMs as a function of the cumulative 131I activity administered 2 years or more before the diagnosis of SPM.
|
No external radiotherapy |
External radiotherapy |
All patients |
|||||
|---|---|---|---|---|---|---|---|
| Type of SPM | Amount of 131I (GBq) | Number of SPM/PYR | RRa (95% CI) | Number of SPM/PYR | RRa (95% CI) | Number of SPM/PYR | RRb (95% CI) |
| Solid cancersc | ⩽0.2 | 186/29625 | 1 (ref) | 84/10629 | 1 (ref) | 270/40254 | 1 (ref) |
| [0.2–3.6] | 98/10795 | 1.2 (0.9–1.5) | 23/2553 | 1.1 (0.7–1.7) | 121/13348 | 1.2 (0.9–1.4) | |
| [3.7–7.3] | 78/14330 | 0.9 (0.7–1.2) | 24/2178 | 1.4 (0.9–2.3) | 102/16508 | 1.0 (0.8–1.3) | |
| [7.4–14.7] | 32/4693 | 1.4 (1.0–2.1) | 12/1184 | 1.6 (0.9–3.0) | 47/5877 | 1.5 (1.0–2.0) | |
| ⩾14.8 | 12/1475 | 1.5 (0.8–2.6) | 7/495 | 2.1 (0.9–4.7) | 19/1970 | 1.6 (1.0–2.6) | |
| Leukaemias | ⩽0.2 | 4/29625 | 1 (ref) | 2/10629 | 1 (ref) | 6/40254 | 1 (ref) |
| [0.2–3.6] | 3/10795 | 1.4 (0.3–6.6) | 1/2553 | 2.2 (0.1–23.5) | 4/13348 | 1.8 (0.4–6.3) | |
| [3.7–18.4] | 4/19644 | 2.6 (0.5–11.8) | 3/3485 | 4.3 (0.7–34.9) | 7/23129 | 3.1 (1.0–10.3) | |
| ⩾18.5 | 0/853 | – | 1/372 | 14.0 (0.6–167.4) | 1/1225 | 7.5 (0.4–48.7) | |
PYR=Number of person-years of follow-up.
a
Relative risks stratified on study group.
b
Relative risks adjusted on external radiotherapy and stratified on study group.
c
All cancers excluding leukaemias, thyroid cancers, and nonmelanoma skin cancers.