Multiple primary cancers in women with gynaecological malignancies: a cancer registry-based study in Umbria region of Italy.

: To investigate the risk of developing multiple primary cancers (MPCs) in patients with previous gynaecological malignancies (cervical, uterine, and ovarian). The study's subjects included all the women on the Umbrian Cancer Registry who were first diagnosed with gynaecological cancer between 1994 and 2009. MPCs were defined according to the rules defined by International Association of Cancer Registries (IACR) and International Agency for Research on Cancer (IARC). Standardized incidence ratios (SIRs) of observed to expected cases were used as the measure of relative risk; its significance and 95% confidence intervals were determined assuming a Pois- son distribution. During the analysed period, the authors observed a total of 346 cases of MPCs in women with cervix (54 cases), corpus of uterus (196 cases), and ovarian (96 cases) malignancies. Significant SIRs were found in all of them, considering all sites combined: 2.43 (95% CI: 1.87-3.14) for cervix, 1.75 (95% CI: 1.52-2.01) for corpus of uterus, and 2.32 (95% CI: 1.90-2.84) for ovary malignancies, with different site-specific risks. Current data confirmed an excess risk of MPCs among women with gynaecological malignancies compared to the general population. The observed site-specific associations are useful to investigate shared risk factors and set up specific follow-up patients.