Incidence of second sarcomas: a cancer registry-based study.
BACKGROUND
In high-quality cancer registration systems, about one in eight incident cancers are second primary cancers. This is due to a combination of careful diagnostic ascertainment, shared genetic determinants, shared exposure to environmental factors and consequences of treatment for first cancer.


METHODS
We used data derived from the Swiss population-based cancer Registries of Vaud and Neuchâtel, including 885,000 inhabitants.


RESULTS
Among 107,238 (52% males) first cancers occurring between 1976 and 2010, a total of 126 second sarcomas were observed through active and passive follow-up versus 68.2 expected, corresponding to a standardized incidence ratio (SIR) of 1.85 (95 % CI 1.5-2.2). Significant excess sarcoma risks were observed after skin melanoma (SIR = 3.0), breast cancer (2.2), corpus uteri (2.7), testicular (7.5), thyroid cancer (4.2), Hodgkin lymphoma (5.7) and leukemias (4.0). For breast cancer, the SIR was 3.4 ≥ 5 years after sarcoma diagnosis.


CONCLUSIONS
The common denominator of these neoplasms is the utilization of radiotherapy in their management. Some sarcomas following breast cancer may be due to shared genetic components (i.e., in the Li-Fraumeni syndrome), as well as possibly to shared environmental factors, with sarcomas, including overweight, selected dietary and reproductive factors which are, however, too little defined for any quantitative risk assessment.
Vaud Cancer Registry and Cancer Epidemiology Unit, Institute of Social and Preventive Medicine (IUMSP), Lausanne University Hospital, Route de la Corniche 10, 1010, Lausanne, Switzerland, fabio.levi@chuv.ch.
Fabio
F
Levi
Lalao
L
Randimbison
Manuela
M
Maspoli-Conconi
Rafael
R
Blanc-Moya
Carlo
C
La Vecchia
D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D012509:Sarcoma / Q000453:epidemiology*; D013557:Switzerland / Q000453:epidemiology