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Summary A protective effect of calcium against colorectal cancer has been described in Anglo-Saxon but not in Latin communities, and no such effect has been observed regarding adenomas. We investigated the relationship between calcium, dairy products and the adenoma-carcinoma sequence in a French region by comparing small adenoma (< 10 mm, n = 154), large adenoma (n = 208) and polyp-free (n = 426) subjects, and cancer cases (n = 171) with population controls (n = 309). There was no protective effect of calcium against colorectal tumours except for low fat calcium and large adenomas in men (OR for highest quintile= 0.3, P for trend = 0.06). There was even a trend towards an increased risk of cancer with dairy calcium in men and nondairy calcium in women. Vitamin D was inversely related to the risk of small adenomas in women (OR for highest quintile = 0.4, P for trend = 0.04). Regarding dairy products, only consumption of yoghurt displayed an inverse relationship with risk of large adenomas, in both men and women. These data failed to demonstrate a protective effect of calcium against colorectal carcinogenesis. They suggest that the type of dairy product might be the important factor with regard to prevention of colorectal tumours. (Benito et al., 1991;Tuyns et al., 1988; Negri et al., 1990). Dairy products have also been studied not only because they are the main source of dietary calcium, but also because other components may be of interest, such as the lactose content or the bacteria in fermented dairy products. To date, no significant association has been described between calcium intake and colorectal adenomas (Kampman et al., 1994a). This finding is all the more important since certain of the current intervention studies with calcium supplements use adenoma recurrence as an end point.France has a tradition of high calcium intake, mainly in the form of cheese. In order to define further the effect of calcium, phosphate, vitamin D and dairy product intake on the adenoma-carcinoma sequence, we carried out a casecontrol study in a French community of the relationship between these nutrients, as well as calcium-containing foods and the different macroscopic steps of colorectal carcinogenesis, namely small adenoma, large adenoma and cancer. Materials and methodsCases and controls A case-control study was set up between 1985 and 1990 to investigate risk factors for the different macroscopic steps of the adenoma-carcinoma sequence. Its general design has already been described Sample size calculations were based on fat intake, one of the suspected major risk factors for colorectal cancer. Considering the proportion of the population exposed to a high-fat diet, with a power of 80% to demonstrate a relative risk of 2.0 at the 5% level of significance, it was calculated that at least 140 cases and 280 controls were needed in each group.Two groups of patients with adenomas and polyp-free controls were selected from the endoscopy lists of all gastroenterologists in the area, whether in private or public practice. Adeno...

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Further studies are warranted to identify more precisely the reasons for lower treatment rates for colorectal cancer in the older population.

Family history ofcolorectal cancer is a risk factor for sporadic colorectal cancer, but it is not known which step of the adenomacarcinoma pathway it influences. This case control study investigated the relation between family history of cancer and colorectal adenomas and cancers. Family history of colorectal cancer (FHCRC) was as frequent in small (<10 mm) adenoma patients (11.7%, n=154) as in polyp free patients (10.6%, n=426), whereas it was more frequent in patients with large adenoma(s) (18.8%, n=208; p<0.01 (Gut 1995; 37: 830-834)

Objectives To study the percentage, suppressive function and plasticity of Treg in giant cell arteritis (GCA), and the effects of glucocorticoids and tocilizumab. Methods Blood samples were obtained from 40 controls and 43 GCA patients at baseline and after treatment with glucocorticoids + IV tocilizumab ( n = 20) or glucocorticoids ( n = 23). Treg percentage and phenotype were assessed by flow cytometry. Suppressive function of Treg was assessed by measuring their ability to inhibit effector T‐cell (Teff) proliferation and polarisation into Th1 and Th17 cells. Results Treg (CD4 + CD25 high FoxP3 + ) frequency in total CD4 + T cells was decreased in active GCA patients when compared to controls (2.5% vs. 4.7%, P < 0.001) and increased after treatment with tocilizumab but worsened after treatment with glucocorticoids alone. Treg lacking exon 2 of FoxP3 were increased in GCA patients when compared to controls (23% vs. 10% of total Treg, P = 0.0096) and normalised after treatment with tocilizumab + glucocorticoids but not glucocorticoids alone. In GCA patients, Treg were unable to control Teff proliferation and induced ˜50% increase in the amount of IL‐17 + Teff, which was improved after in vitro blockade of the IL‐6 pathway by tocilizumab. Conclusion This study reports quantitative and functional disruptions in the regulatory immune response of GCA patients and demonstrates that, unlike glucocorticoids, tocilizumab improves Treg immune response.

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