Donation frequency, iron loss, and risk of cancer among blood donors.

BACKGROUND: Long-term deleterious effects of repeated blood donations may be masked by the donors' healthy lifestyle. To investigate possible effects of blood donation and iron loss through blood donation on cancer incidence while minimizing "healthy donor effects," we made dose-response comparisons within a cohort of Swedish and Danish blood donors. METHODS: We used a nested case-control study design, in which case patients were defined as all donors who were diagnosed with a malignancy between their first recorded blood donation and study termination (n = 10866). Control subjects (n = 107140) were individually matched on sex, age, and county of residence. Using conditional logistic regression, we estimated relative risks of cancer according to number of blood donations made or estimated iron loss 3-12 years before a case patient was diagnosed with cancer. All statistical tests were two-sided. RESULTS: No clear association was observed between number of donations and risk of cancer overall. However, between the lowest (< or = median, < 0.75 g) and highest (> 90th percentile, > 2.7 g) categories of estimated iron loss, there was a trend (P(trend) < .001) of decreasing risk for cancers of the liver, lung, colon, stomach, and esophagus, which are thought to be promoted by iron overload (combined odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.58 to 0.84), but only among men and only with a latency of 3-7 years. The risk of non-Hodgkin lymphoma was higher among frequent plasma donors (> 25 vs 0 donations, OR = 2.14, 95% CI = 1.22 to 3.74). CONCLUSIONS: Repeated blood donation was not associated with increased or decreased risk of cancer overall. The lack of consistency across latency periods casts doubt on an apparent association between reduced cancer risk and iron loss in men. The positive association between frequent plasma donation and risk of non-Hodgkin lymphoma deserves further exploration.

Storage of platelet concentrates from pooled buffy coats made of fresh and overnight-stored whole blood processed on the novel Atreus 2C+ system: in vitro study.

BACKGROUND: The Atreus 2C+ system (Gambro BCT) automatically separates whole blood (WB) into buffy coat (BC), red blood cells (RBC), and plasma and transfers the components into separate containers. After processing with the Atreus, 4 to 6 BC units can be pooled and processed into leukoreduced platelets (PLTs) by use of the automated OrbiSac BC system (Gambro BCT). The aim of our in vitro study was to investigate the effects of holding either WB or BC overnight before preparation of PLTs by use of the Atreus 2C+ system for BC preparation. A standard routine procedure involving conventional blood containers for the preparation of BC combined with the OrbiSac process (top-and-top system; Terumo) was used as a reference. STUDY DESIGN AND METHODS: WB was either processed within 8 hours after collection ("fresh blood") or stored overnight before processing. WB units were separated into BC, RBC, and plasma units and transferred into individual containers. Either the BC or the WB units rested overnight at 22 +/- 2 degrees C. Six ABO-identical BCs, obtained from either fresh or overnight-stored WB, were pooled and processed with the OrbiSac BC system to obtain leukoreduced PLTs. In total, 20 Atreus and 10 reference (leukoreduced PLTs) samples were analyzed for various in vitro variables during the 7-day storage period. RESULTS: No significant difference in glucose consumption, lactate production, mean PLT volume, LDH activity, bicarbonate, ATP, RANTES, and the expression of CD62p and CD42b between groups was detected. pH was maintained at greater than 7.0 (Day 7). Swirling remained at the highest levels (score, 2) for all units throughout storage. CONCLUSION: PLTs derived from BCs, obtained from either fresh or overnight-stored WB processed on the novel automated Atreus 2C+ system, were equivalent to control PLTs with regard to PLT in vitro characteristics during 7 days of storage. Stable recovery of PLTs and satisfactory PLT content according to current standards were also found.

Cancer incidence in blood transfusion recipients.

BACKGROUND: Blood transfusions may influence the recipients' cancer risks both through transmission of biologic agents and by modulation of the immune system. However, cancer occurrence in transfusion recipients remains poorly characterized. METHODS: We used computerized files from Scandinavian blood banks to identify a cohort of 888,843 cancer-free recipients transfused after 1968. The recipients were followed from first registered transfusion until the date of death, emigration, cancer diagnosis, or December 31, 2002, whichever came first. Relative risks were expressed as ratios of the observed to the expected numbers of cancers, that is, standardized incidence ratios (SIRs), using incidence rates for the general Danish and Swedish populations as a reference. All statistical tests were two-sided. RESULTS: During 5,652,918 person-years of follow-up, 80,990 cancers occurred in the transfusion recipients, corresponding to a SIR of 1.45 (95% confidence interval [CI] = 1.44 to 1.46). The SIR for cancer overall decreased from 5.36 (95% CI = 5.29 to 5.43) during the first 6 months after transfusion to 1.10 or less for follow-up periods more than 2 years after the transfusion. However, the standardized incidence ratios for cancers of the tongue, mouth, pharynx, esophagus, liver, and respiratory and urinary tracts and for squamous cell skin carcinoma remained elevated beyond 10 years after the transfusion. CONCLUSIONS: The marked increase in cancer risk shortly after a blood transfusion may reflect the presence of undiagnosed occult cancers with symptoms that necessitated the blood transfusion. The continued increased risk of tobacco- and alcohol-related cancers suggests that lifestyle and other risk factors related to conditions prompting transfusion rather than transfusion-related exposures per se are important to the observed cancer occurrence in the recipients.

Improving health profile of blood donors as a consequence of transfusion safety efforts.

BACKGROUND: Transfusion safety rests heavily on the health of blood donors. Although they are perceived as being healthier than average, little is known about their long-term disease patterns and to which extent the blood banks' continuous efforts to optimize donor selection has resulted in improvements. Mortality and cancer incidence among blood donors in Sweden and Denmark was investigated. STUDY DESIGN AND METHODS: All computerized blood bank databases were compiled into one database, which was linked to national population and health data registers. With a retrospective cohort study design, 1,110,329 blood donors were followed for up to 35 years from first computer-registered blood donation to death, emigration, or December 31, 2002. Standardized mortality and incidence ratios expressed relative risk of death and cancer comparing blood donors to the general population. RESULTS: Blood donors had an overall mortality 30 percent lower (99% confidence interval [CI] 29%-31%) and cancer incidence 4 percent lower (99% CI 2%-5%) than the background population. Mortality rates and cancer incidence were lowest for outcomes that are recognized as being related to lifestyle factors such as smoking or to the selection criteria for blood donation. Blood donors recruited in more recent years exhibited a lower relative mortality than those who started earlier. CONCLUSION: Blood donors enjoy better than average health. Explicit and informal requirements for blood donation in Scandinavia, although mostly of a simple nature, have successfully refined the selection of a particularly healthy subpopulation.

Risk of cancer after blood transfusion from donors with subclinical cancer: a retrospective cohort study.

BACKGROUND: Although mechanisms for detection of short-term complications after blood transfusions are well developed, complications with delayed onset, notably transmission of chronic diseases such as cancer, have been difficult to assess. Our aim was to investigate the possible risk of cancer transmission from blood donors to recipients through blood transfusion. METHODS: We did a register-based retrospective cohort study of cancer incidence among patients who received blood from donors deemed to have a subclinical cancer at the time of donation. These precancerous donors were diagnosed with a cancer within 5 years of the donation. Data from all computerised blood bank registers in Sweden and Denmark gathered between 1968 and 2002 were merged into a common database. Demographic and medical data, including mortality and cancer incidence, were ascertained through linkages with nationwide, and essentially complete, population and health-care registers. The risk of cancer in exposed recipients relative to that in recipients who received blood from non-cancerous donors was estimated with multivariate Poisson regression, adjusting for potential confounding factors. FINDINGS: Of the 354 094 transfusion recipients eligible for this analysis, 12,012 (3%) were exposed to blood products from precancerous donors. There was no excess risk of cancer overall (adjusted relative risk 1.00, 95% CI 0.94-1.07) or in crude anatomical subsites among recipients of blood from precancerous donors compared with recipients of blood from non-cancerous donors. INTERPRETATION: Our data provide no evidence that blood transfusions from precancerous blood donors are associated with increased risk of cancer among recipients compared with transfusions from non-cancerous donors.

Major ABO blood group mismatch increases the risk for graft failure after unrelated donor hematopoietic stem cell transplantation.

Two hundred twenty-four patients with leukemia transplanted with an unrelated donor between 1991 and 2003 at the Karolinska University Hospital were analyzed according to association between graft failure and ABO, RhD, MNSs, and Kidd blood group antigen compatibility. Median age was 29 years (range: 0-55). Conditioning consisted of total-body irradiation or busulfan-based myeloablative conditioning. A bone marrow graft was given to 152 patients, and 72 patients received peripheral blood stem cells. Most patients received graft-versus-host disease prophylaxis with cyclosporine and MTX. Graft failure (GF) was seen in 6 (2.7%) patients. In the multivariate analysis major ABO mismatch (odds ratio [OR] 14.9, 95% confidence interval [CI] 2.01-110, P = .008) and HLA-allele mismatch (6.42, 1.19-34.8, P = .03) was significantly associated to GF. In patients with and without major ABO mismatch the incidence of GF was 7.5% and 0.6% (P = .02), respectively. Using an ABO major mismatched graft increases the risk for GF after unrelated donor hematopoietic stem cell transplantation.

A prospective randomized trial of a prophylactic platelet transfusion trigger of 10 x 10(9) per L versus 30 x 10(9) per L in allogeneic hematopoietic progenitor cell transplant recipients.

BACKGROUND: The impact of lowering the platelet (PLT) count threshold for prophylactic PLT transfusion on bleeding and PLT use in allogeneic hematopoietic progenitor cell (HPC) transplant recipients is a matter of debate. STUDY DESIGN AND METHODS: In 166 patients, randomly assigned to receive prophylactic PLT transfusion at a trigger level less than 10 x 10(9) PLTs per L (T10; n = 79) or less than 30 x 10(9) per L (T30; n = 87), the number of PLT and red blood cell (RBC) transfusions given and the number of hemorrhagic events (WHO Grades 2-4) were recorded. RESULTS: No significant differences were found between the two groups regarding the clinical outcome variables (i.e., bacteremia, engraftment, graft-vs.-host disease [GVHD], hospital stay, death, and survival) or in the median total number of RBC transfusions given. The incidence, in Group T10 18 percent (14/79) and in Group T30 15 percent (13/87), as well as the type of bleeding were comparable. No deaths were attributed to hemorrhages. The number of PLT units transfused, however, was significantly lower in Group T10 (median, 4; range, 0-32), than in Group T30 (median, 10; range, 0-48; p < 0.001). Apart from the trigger level, the day of engraftment, the presence of acute GVHD, or bacteremia also affected the number of PLT transfusions. CONCLUSION: A prophylactic PLT transfusion trigger level of less than 10 x 10(9) PLTs per L instead of less than 30 x 10(9) PLTs per L in allogeneic HPC transplant recipients was found to be safe and resulted in a decreased use of PLTs.

Photopheresis for the treatment of refractory renal graft rejection.

Acute rejection episodes still occur after kidney transplantation in spite of modern immunosuppressive protocols including combined tacrolimus, mycophenolate mofetil, and prednisolone. The authors present seven cases of biopsy-proven acute rejection after kidney transplantation refractory to conventional rejection therapy with repeated pulses of high-dose steroids followed by polyclonal or monoclonal antibodies that responded well to photopheresis treatment. Photopheresis is an atoxic immunomodulatory apheresis-based treatment with no generalized immunosuppressive action; rather, it is directed at suppressing donor-specific T-cell clones. At the last follow-up, 9 to 43 months after transplantation, all patients had functioning grafts, with serum creatinine levels ranging from 105 to 312 microM. The authors conclude that photopheresis treatment contributed to the favorable outcome. Therefore, the authors are presently designing a prospective, randomized trial to evaluate the effect of photopheresis as an adjuvant prophylactic treatment after renal transplantation.