Cancer risk following organ transplantation: a nationwide cohort study in Sweden

Abstract

A substantial excess risk of lymphomas and nonmelanoma skin cancer has been demonstrated following organ transplantation. Large sample size and long follow-up time may, however, allow more accurate risk estimates and detailed understanding of long-term cancer risk. The objective of the study was to assess the risk of cancer following organ transplantation. A nationwide cohort study comprising 5931 patients who underwent transplantation of kidney, liver or other organs during 1970 -1997 in Sweden was conducted. Complete follow-up was accomplished through linkage to nationwide databases. We used comparisons with the entire Swedish population to calculate standardised incidence ratios (SIRs), and Poisson regression for multivariate internal analyses of relative risks (RRs) with 95% confidence intervals (CI). Overall, we observed 692 incident first cancers vs 171 expected (SIR 4.0; 95% CI 3.7 -4.4). We confirmed marked excesses of nonmelanoma skin cancer (SIR 56.2; 95% CI 49.8 -63.2), lip cancer (SIR 53.3; 95% CI 38.0 -72.5) and of non-Hodgkin's lymphoma (NHL) (SIR 6.0; 95% CI 4.4 -8.0). Compared with patients who underwent kidney transplantation, those who received other organs were at substantially higher risk of NHL (RR 8.4; 95% CI 4.3 -16). Besides, we found, significantly, about 20-fold excess risk of cancer of the vulva and vagina, 10-fold of anal cancer, and five-fold of oral cavity and kidney cancer, as well as two-to four-fold excesses of cancer in the oesophagus, stomach, large bowel, urinary bladder, lung and thyroid gland. In conclusion, organ transplantation entails a persistent, about four-fold increased overall cancer risk. The complex pattern of excess risk at many sites challenges current understanding of oncogenic infections that might become activated by immunologic alterations.

Risk of Kaposi's sarcoma and of other cancers in Italian renal transplant patients

“…With respect to the increased risks for NHL and renal cancer, our results agree with previous investigations (Kinlen, 1992;Birkeland et al, 1995;Adami et al, 2003). It is noteworthy that all cases of renal cancer in this study involved the native kidney, a distinction not mentioned in previous studies.…”

“…The overall increase in cancer risk we found (1.8-fold) is somewhat lower than that reported from previous investigations in transplant patients (Kinlen et al, 1979;Birkeland et al, 1995;Hoshida et al, 1997;Adami et al, 2003), but the exclusion in our analysis of nonmelanoma skin cancers explains a large part of this difference.…”

“…Of these, 1340 received their transplants at Niguarda Hospital, Milan, between 1972and 504 at Policlinico Gemelli Hospital, Rome, between 1970. As with other investigations, we excluded patients who survived less than 10 days after transplant, those with a pretransplant history of cancer, or who developed cancer in the 30-day period after transplantation (Adami et al, 2003;Pedotti et al, 2003). Nonmelanoma skin cancers were not evaluated since information on basal cell carcinoma was not recorded and that on squamous cell carcinoma might not have been complete.…”

“…Kaposi's sarcoma (KS) has been frequently reported in transplant patients in the United States (Penn, 2000), in the Middle East (Qunibi et al, 1988) and in Italy (Montagnino et al, 1996;Pedotti et al, 2003), but the excess risk has not been closely quantified. No increased risk of KS has been reported in transplant patients from the Nordic countries (Birkeland et al, 1995(Birkeland et al, , 2000Adami et al, 2003), or Japan (Hoshida et al, 1997).…”

“…The overall cancer risk is three-to four-fold elevated, but some specific cancers show greater increases (Kinlen, 1992). For nonmelanoma skin cancers and lip cancer, the relative risks are increased 10-to 60-fold (Kinlen et al, 1979;Birkeland et al, 1995;Adami et al, 2003), while the excess of non-Hodgkin's lymphoma (NHL) is about five-to 10-fold (Hoshida et al, 1997;Birkeland et al, 2000;Adami et al, 2003). Kaposi's sarcoma (KS) has been frequently reported in transplant patients in the United States (Penn, 2000), in the Middle East (Qunibi et al, 1988) and in Italy (Montagnino et al, 1996;Pedotti et al, 2003), but the excess risk has not been closely quantified.…”