Immunodeficiency is associated with higher
cancer incidence. However, it is unknown whether there is a link between immunodeficiency and development of multiple primary
malignancies. In the present study we analyse this link focusing on kidney-transplanted patients, as they are at higher risk of developing
cancer due to the chronic assumption of
immunosuppressants. We followed up 1200 patients who underwent
kidney transplantation between 1980 and 2012. A total of 77/1200 kidney-transplanted patients developed
cancer and 24 of them developed multiple
cancers. Most multiple
cancers were synchronous with a nonsignificant association between
cancer and rejection episodes. In the general
cancer population, one-ninth of patients are at higher risk of developing a second
tumor over a lifetime; hence it would be reasonable to conclude that, from a merely theoretical and statistical viewpoint, long-term transplanted patients potentially have a higher risk of developing
MPMs. However, data did not confirm this assumption, probably because these patients die before a second primary
malignancy appears. Despite many observations on the increased incidence of different
tumor types in immunodeficient patients and despite immunosuppression certainly being a predisposing factor for the multicancer syndrome, data so far are not robust enough to justify a correlation between immunodeficiency and multiple primary
malignancies in transplanted patients.