The effect of social class on survival was assessed in a cohort of cancer patients identified from the nationwide population-based Finnish Cancer Registry. The cohort consisted of all reported cases of the 12 most common types of cancer occurring in Finland between 1971 and 1985 among persons born in 1906-1945 (n = 106,661). Social class information based on occupation was obtained individually for each patient from the population census of 1970. Both observed and corrected (i.e., cause of death-specific) 5-year survival rates were used in the analyses. A statistically significant linear effect of social class on age-adjusted relative risk of cancer death was observed in six of 12 cancer types among men and in nine of 12 among women; and the risk was highest for those in the lowest social class. The relative risk of death due to cancer for social class I (highest) relative to social class IV (lowest) was lowest in bladder cancer (relative risk (RR) = 0.46, 95% confidence interval (CI) 0.34-0.61) and kidney cancer (RR = 0.61, 95% CI 0.48-0.78) among men and in corpus uteri (RR = 0.51, 95% CI 0.36-0.72) and rectum cancer (RR = 0.56, 95% CI 0.42-0.74) among women. The differences between results obtained using corrected and observed survival rates were small. These findings indicate that social class is an important determinant of cancer patient survival. Additional research is required to clarify the etiology of the social class differences and to identify factors that could be used for developing strategies to diminish such inequalities.

The leukemia risk associated with partial-body radiotherapy for uterine corpus cancer was small; about 14 excess leukemia cases were due to radiation per 10,000 women followed for 10 years. Women aged 65 years or older had a radiation risk comparable with that found in younger women. The relationship of leukemia risk to radiation dose was found to be complex due to the competing processes of cell killing, transformation, and repair. At very high doses delivered at high rates, destruction of cells likely dominates, and the risk per unit dose is low. In the low dose range, where dose was protracted and delivered at relatively low dose rates, the leukemia risk appears lower than that projected from risk estimates derived from the instantaneous whole-body exposures of atomic bomb survivors.

A collaborative group of cancer registries and hospitals carried out a case-control study of tumours of the bladder in women who had previously been treated for ovarian cancer. A total of 63 cases of bladder tumours were identified, and 188 controls were selected matching for age, year of ovarian cancer diagnosis and survival time. Full details of the treatment for ovarian cancer were sought for both cases and for controls. The risk of bladder tumours was increased for patients who had been treated by radiotherapy alone (1.9; 95% confidence interval, 0.77-4.9), by chemotherapy alone (3.2; 0.97-10), and by chemotherapy and radiotherapy (5.2; 1.6-16), when comparison was made with patients treated only by surgery. Patients treated by chemotherapy were separated into 2 groups according to whether they had received cyclophosphamide. Among those who had, there was a clear increase in risk (approximately 4-fold) regardless of whether or not they had also received radiotherapy. For those who received only other drugs, risk was increased substantially among patients who had also been treated by radiation, as compared with patients treated by surgery alone, and those who had received radiotherapy only. Both melphalan and thiotepa were implicated as potential bladder carcinogens on the basis of these results. The estimated risk of bladder tumours due to cyclophosphamide was more than twice the risk following radiation to the bladder, and it appeared substantially earlier. For both agents, the risk continued to increase more than 10 years after treatment began.

Objective-To determine whether patients with multiple myeloma treated in three consecutive clinical trials of chemotherapy of the Finnish Leukaemia Group during

BackgroundScreening for colorectal cancer (CRC) with guaiac-based faecal occult-blood test (FOBT) has been reported to reduce CRC mortality in randomised trials in the 1990s, but not in routine screening, so far. In Finland, a large randomised study on biennial FOB screening for CRC was gradually nested as part of the routine health services from 2004. We evaluate the effectiveness of screening as a public health policy in the largest population so far reported.MethodsWe randomly allocated (1:1) men and women aged 60–69 years to those invited for screening and those not invited (controls), between 2004 and 2012. This resulted in 180 210 subjects in the screening arm and 180 282 in the control arm. In 2012, the programme covered 43% of the target age population in Finland.ResultsThe median follow-up time was 4.5 years (maximum 8.3 years), with a total of 1.6 million person-years. The CRC incidence rate ratio between the screening and control arm was 1.11 (95% CI 1.01 to 1.23). The mortality rate ratio from CRC between the screening and control arm was 1.04 (0.84 to 1.28), respectively. The CRC mortality risk ratio was 0.88 (0.66 to 1.16) and 1.33 (0.94 to 1.87) in males and females, respectively.ConclusionsWe did not find any effect in a randomised health services study of FOBT screening on CRC mortality. The substantial effect difference between males and females is inconsistent with the evidence from randomised clinical trials and with the recommendations of several international organisations. Even if our findings are still inconclusive, they highlight the importance of randomised evaluation when new health policies are implemented.Trial registration002_2010_august.