Gustaf Edgren

BACKGROUND: There are reports about the changing epidemiology of tongue squamous cell carcinoma (SCC), with recent reports indicating an increasing incidence in young women. METHODS: Data on incident cases of tongue SCC were collected from cancer registries worldwide. RESULTS: Data from a total of 22 cancer registries and 89,212 incident cases of tongue SCC worldwide were included. Most areas experienced an incidence increase ranging from 0.4% to 3.3% per year. There was a significant difference in the incidence increase between sexes in 11 of the 22 registries. In 14 of the 22 registries studied, the increase in incidence of tongue SCC was higher in the group of subjects <45 years old than those ≥45 years old. CONCLUSION: This study suggests a general but not universal increase in the incidence of tongue SCC worldwide. In some regions of the world, we observed a shifting trend toward women and/or younger patients. © 2016 Wiley Periodicals, Inc. Head Neck 39: 297-304, 2017.

Organ transplant recipients are at increased risk of a wide range of malignancies, especially cutaneous squamous cell carcinomas (SCC). Few previous population-based studies have quantified and compared cancer risks according to graft type and with long-term follow-up. Using nationwide Swedish registers, we identified 10,476 recipients transplanted from 1970 to 2008 and followed them for cancer occurrence. Relative risks of cancer in comparison with the general population were expressed as standardized incidence ratios (SIR) and within the transplanted cohort as incidence rate ratios (IRR). During a total follow-up of 93,432 person-years, patients were diagnosed with 1,175 cancers excluding SCC, and with 2,231 SCC, SIR(cancer excl SCC) 2.4 (95% CI, 2.2-2.5); SIR(SCC) 121 (95% CI, 116-127). Cancer risks were most increased among heart and/or lung recipients SIR(cancer excl SCC) 3.3 (95% CI, 2.8-4.0); SIR(SCC) 198 (95% CI, 174-224), followed by kidney SIR(cancer excl SCC) 2.3 (95% CI, 2.1-2.4); SIR(SCC) 121 (95% CI, 116-127) and liver recipients SIR(cancer excl SCC) 2.3 (95% CI, 1.9-2.8); SIR(SCC) 32 (95% CI, 24-42). During follow-up, risk of cancer excluding SCC remained stable while risk of SCC tripled over 20 years irrespective of graft type, partly due to a subgroup of patients developing new SCCs at a rapidly increasing rate. In summary, post-transplant cancer risk varied by transplanted organ and by cancer site, with the bulk of the excess risk driven by an exceptionally high and accelerating risk of SCC. These findings underscore the importance of regular skin screening in organ transplant recipients.

<h3>Objective</h3> About 20 years ago, the scientific community was first alerted to an enigmatic increase of oesophageal adenocarcinomas in the UK and USA. Subsequently, a virtual epidemic—still unexplained—was confirmed in several western countries. Detailed descriptive data might provide clues to its causes. <h3>Design</h3> We collected data on incident cases of oesophageal adenocarcinoma from population-based cancer registries in Australia, Europe, North America and Asia. We calculated age-standardised incidence rates and fitted log-linear Poisson models to assess annual rate of increase and to disentangle age-period-cohort effects, linear spine models to estimate rate of increase since 1985, and Joinpoint models to identify possible inflection points. <h3>Results</h3> With considerable between-registry variation in magnitude and timing, we found a consistent dramatic increase in incidence with an observed or estimated start between 1960 and 1990. The average annual increase ranged from 3.5% in Scotland to 8.1% in Hawaii with similar proportional increase among men and women in most registries and a maintained three to sixfold higher incidence among men. Generally, calendar period was a more important determinant of incidence trends than birth cohort. Where possible to conduct, Joinpoint analyses indicated that the onset of the epidemic varied considerably even between neighbouring countries. <h3>Conclusions</h3> Given the preponderant period effect and the abrupt onset observed or inferred in most populations, the epidemic appears to be caused by some exposure that was first introduced around 1950. At least 30 years9 variation in estimated time of onset opens prospects for hypothesis-generating ecological analyses.

Blood group A was found to be associated with gastric cancer in the 1950s. Strikingly, for peptic ulcers an increased risk has been shown for blood group O. However, previous investigations have generally been poorly conducted and have failed to take a unifying approach to these observations. Using the Scandinavian Donations and Transfusions (referred to as "SCANDAT") database, the authors established a cohort of Swedish and Danish blood donors with known blood type and followed these for the occurrence of gastric cancer and peptic ulcers through December 31, 2002. Cases were ascertained by using nationwide cancer and hospital registers. Altogether, 1,089,022 donors were followed for up to 35 years, during which 688 gastric cancer cases and 5,667 peptic ulcer cases accrued. Poisson regression analyses confirmed an increased risk of gastric cancer among individuals with blood group A (incidence rate ratio = 1.20, 95% confidence interval: 1.02, 1.42) and conversely that peptic ulcer risk was instead highest among those with blood group O. In this large, population-based cohort study, the authors have confirmed the association between blood group A and gastric cancer. In addition, they give further support to the notion that individuals with blood group O have a higher risk of peptic ulcers than those with other blood groups.