The Inside Edge (June 2009)
A UK trial is assessing the effect of annual screening on mortality using two strategies, multimodal (primary screen with the CA125 blood test plus second-line transvaginal ultrasound) and transvaginal ultrasound alone. The trial has recruited 202,638 postmenopausal women aged 50-74 years who will be screened until the end of 2012 and followed until the end of 2014. Initial results show that 90 per cent (34 out of 38) of cancers were detected by multimodal screening and 75 per cent (24 out of 32) by ultrasound. Almost half of the cancers detected were stage I/II. The authors say the results show that both strategies have encouraging performance characteristics and are feasible on a large scale. (Menon U, Gentry-Maharaj A, Hallett R et al. Lancet Oncol 2009;10:327-40)
Dietary restriction can reduce cancer incidence and growth, and therapies that mimic the effects of dietary restriction are being investigated as anticancer agents. However, not all tumours are sensitive in this way. US researchers have found that sensitivity depends on the activity of the phosphatidylinositol 3-kinase (PI3K) pathway. If the PI3K pathway is active, dietary restriction does not affect cancer cells; if it is inactive, tumours are sensitive. The study has shown that cancer cells forming tumours that are resistant to dietary restriction carry mutations that activate the PI3K pathway. The findings may help to predict which cancers will respond to dietary restriction. (Kalaany NY, Sabatini DM. Nature 2009;458:725-31)
Men with benign adrenal tumours experience more bone fractures, according to an observational study from Italy. Researchers followed 88 men with benign adrenal tumours and 90 matched controls for 12 months. About one-fifth of tumour patients had slightly elevated cortisol (subclinical hypercortisolism) diagnosed in the presence of two of the following: urinary free cortisol >193.1nmol/L, cortisol after 1mg dexamethasone suppression test >82.8nmol/L, ACTH levels <2.2pmol/L. These patients had lower femoral neck and lumbar spine bone mineral density than controls and tumour patients without subclinical hypercortisolism, as well as a higher prevalence of fractures. The researchers conclude that subtly raised cortisol can cause the same clinical outcome as overtly raised cortisol, so there is a need for bone screening in these patients. (Chiodini I, Viti R, Coletti F et al. Clin Endocrinol (Oxf) 2009;70:208-13)
A rule to predict the risk of lymph node metastasis in elderly women with breast cancer has been developed by US researchers. Hormone receptor positive breast cancer patients aged 70 or over were divided into a training (n = 554) and a test group (n = 146); 15.9 and 16.2 per cent were lymph node positive, respectively. Univariate analysis showed that patient age, tumour size, palpability, grade and lymphovascular invasion predicted lymph node status. On multivariate analysis, patient age, tumour size and lymphovascular invasion remained significant. A rule was created and patients were categorised into quartiles by predicted risk, with the result that 5.4 and 0 per cent of those in the lowest quartile were node positive in training and test sets, respectively. (Chagpar AB, McMasters KM, Edwards MJ. Ann Surg 2009;249:455-60)
Omega-3 fatty acids, such as docosahexaenoic acid (DHA), that are derived from oily fish could be a useful addition to the anticancer armoury, an Egyptian study suggests. The researchers evaluated the anti-tumour effects of DHA in mice, alone or in combination with cisplatin, and assessed its effect on cisplatin-induced nephrotoxicity in rats. Treatment with DHA (125 and 250mg/kg) alone reduced tumour size (38 and 79 per cent, respectively); when used in combination with cisplatin, DHA markedly enhanced the chemopreventive effects of this anticancer agent. The researchers also found that nephrotoxicity in rats due to cisplatin therapy could be ameliorated by treatment with DHA 250mg/kg. (Elmesery ME, Algayyar MM, Salem HA et al. Cell Div 2009;4:6)
Originally published in the June 2009 edition of MIMS Oncology & Palliative Care.