Long-term effect of arsenic exposure: Results from an occupational cohort study

BACKGROUND

In 1976 in Manfredonia (Italy), arsenic was released into the atmosphere due to an accident in a petrochemical plant. We aimed to analyze the mortality of workers involved in the factory for the site cleaning activities.

METHODS

The cohort consisted of 1467 workers grouped into contract, fertilizer, and plastic workers. The outcome of interest was mortality for specific causes. Standardized mortality ratios (SMR) and 95% confidence intervals (95%CI) were computed.

RESULTS

For all workers and all causes of death combined, the SMR was less than 1.0. Mortality ratios were increased for malignant neoplasms of the pleura, bone and melanoma of the skin. Contract workers, the group mostly exposed to arsenic, showed statistically significant SMRs for several malignancies, in particular for lung cancer (SMR = 1.26; 95%CI: 1.05-1.54).

CONCLUSIONS

Overall, the results reported here on mortality among persons occupationally exposed to arsenic are consistent with the literature and biologically plausible.

Risk of cancer incidence before the age of 15 years after exposure to ionising radiation from computed tomography: results from a German cohort study

The aim of this cohort study was to assess the risk of developing cancer, specifically leukaemia, tumours of the central nervous system and lymphoma, before the age of 15 years in children previously exposed to computed tomography (CT) in Germany. Data for children with at least one CT between 1980 and 2010 were abstracted from 20 hospitals. Cancer cases occurring between 1980 and 2010 were identified by stochastic linkage with the German Childhood Cancer Registry (GCCR). For all cases and a sample of non-cases, radiology reports were reviewed to assess the underlying medical conditions at time of the CT. Cases were only included if diagnosis occurred at least 2 years after the first CT and no signs of cancer were recorded in the radiology reports. Standardised incidence ratios (SIR) using incidence rates from the general population were estimated. The cohort included information on 71,073 CT examinations in 44,584 children contributing 161,407 person-years at risk with 46 cases initially identified through linkage with the GCCR. Seven cases had to be excluded due to signs possibly suggestive of cancer at the time of first CT. Overall, more cancer cases were observed (O) than expected (E), but this was mainly driven by unexpected and possibly biased results for lymphomas. For leukaemia, the SIR (SIR = O/E) was 1.72 (95 % CI 0.89-3.01, O = 12), and for CNS tumours, the SIR was 1.35 (95 % CI 0.54-2.78, O = 7). Despite careful examination of the medical information, confounding by indication or reverse causation cannot be ruled out completely and may explain parts of the excess. Furthermore, the CT exposure may have been underestimated as only data from the participating clinics were available. This should be taken into account when interpreting risk estimates.

Pattern of care and results of radiotherapy in patients 80 years old and over

BACKGROUND AND AIMS

Cancer incidence increases with age and several cancer types are observed in older patients, so the need for radiotherapy (RT) in treatment of older patients with cancer is also on the rise. This study's aims to evaluate retrospectively the pattern of care and the feasibility of RT in elderly patients (80 years old and over) treated with different intents, and the impact of RT prescription on survival.

MATERIALS AND METHODS

We reviewed 191 patient charts from the years 2005-2007, recording age, intent of treatment, site, and type of RT. Crude and actuarial survival were estimated.

RESULTS

One hundred patients were males (M) and 91 females (F); 162 were seen on an outpatient basis, 29 as inpatients. A total of 138 patients were recruited for RT; 113 were treated, 112 completed RT. The ratio to all treated patients was 113/2125 (5.3%). Overall (treated and non-treated) cumulative survival probability was 71% for the first year, 45% for the second and 27% for the third. For treated patients, the cumulative survival probability was 67% for the first year, 43% for the second year and 23% for the third year, while for untreated patients it was 76% for the first year, 47% for the second year and 32% for the third year (Log-rank test: p = 0.23).

CONCLUSIONS

RT did not decrease survival in elderly patients.