Granger Robert H, Blizzard Leigh, Fryer Jayne L, Dwyer Terence
Menzies Research Institute, Hobart, Australia.
BMC Cancer. 2006 May 30;6:141. doi: 10.1186/1471-2407-6-141.
Human studies of dietary fat as a possible risk factor for cutaneous malignant melanoma (CMM) and non-melanoma skin cancer (NMSC)--principally basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)--have produced inconsistent results. We had the opportunity to examine the association concurrently for all three types of skin cancer in a population-based study in Tasmania, Australia, involving 652 cases of CMM, BCC and SCC and a common set of 471 controls.
Histopathologically-confirmed cases of CMM, BCC and SCC were ascertained from the Tasmanian Cancer Registry (TCR), and controls were selected at random from the state's electoral roll. We compared subjects categorised by thirds of dietary fat intake score measured by the 'Dobson short fat questionnaire', with logistic regression models that adjusted for age, sex, skin type and usual sun exposure. We then followed all subjects for 56-80 months until 31 August, 2004 for a new NMSC using record linkage with both the TCR and the Births, Deaths, and Marriages registry. Incidence rates were calculated and ratios of rates were estimated using Poisson models.
Relative to subjects in the lowest fat intake category, the odds ratios (OR) comparing cases and controls were OR = 0.76 (95% CI: 0.56-1.03) for medium fat intake, and OR = 0.62 (95% CI: 0.45-0.85) for high fat intake, with a significant (p < 0.01) trend of reduced odds ratio with higher category dietary fat intake. Among cases, the incidence rate ratio (IRR) relative to those with lowest fat score was IRR = 0.72 (95% CI: 0.50-1.03) for medium fat intake, and IRR = 0.82 (95% CI: 0.56-1.20) for highest fat intake (linear trend p = 0.30).
Using the same dietary instrument with two study designs in the same Caucasian population, we found no evidence that high fat intake increases the risk of developing melanoma or non-melanoma skin cancers. Instead, our results suggest a risk reduction for high fat intake.
关于膳食脂肪作为皮肤恶性黑色素瘤（CMM）和非黑色素瘤皮肤癌（NMSC）——主要是基底细胞癌（BCC）和鳞状细胞癌（SCC）——可能的风险因素的人体研究结果并不一致。我们有机会在澳大利亚塔斯马尼亚州一项基于人群的研究中，同时考察这三种皮肤癌之间的关联，该研究纳入了652例CMM、BCC和SCC病例以及471例共同的对照。
从塔斯马尼亚癌症登记处（TCR）确定经组织病理学确诊的CMM、BCC和SCC病例，并从该州选民名册中随机选择对照。我们将根据“多布森简短脂肪问卷”测量的膳食脂肪摄入得分按三分位数分类的受试者进行比较，使用对年龄、性别、皮肤类型和日常日晒进行调整的逻辑回归模型。然后，我们对所有受试者随访56 - 80个月，直至2004年8月31日，通过与TCR以及出生、死亡和婚姻登记处的记录链接来确定新的NMSC病例。计算发病率，并使用泊松模型估计发病率比。
与脂肪摄入量最低类别的受试者相比，中等脂肪摄入量时病例与对照的比值比（OR）为OR = 0.76（95%可信区间：0.56 - 1.03），高脂肪摄入量时为OR = 0.62（95%可信区间：0.45 - 0.85），随着膳食脂肪摄入量类别升高，比值比有显著降低趋势（p < 0.01）。在病例中，相对于脂肪得分最低者，中等脂肪摄入量时的发病率比（IRR）为IRR = 0.72（95%可信区间：0.50 - 1.03），高脂肪摄入量时为IRR = 0.82（95%可信区间：0.56 - 1.20）（线性趋势p = 0.30）。
在同一白种人群中使用相同的膳食工具进行两种研究设计，我们没有发现证据表明高脂肪摄入会增加患黑色素瘤或非黑色素瘤皮肤癌的风险。相反，我们的结果表明高脂肪摄入有降低风险的作用。
