Diet, smoking and lung cancer: a case-control study of 1000 cases and 1500 controls in South-West England.

We have examined the relationship between diet and lung cancer in a case-control study of 982 cases of lung cancer and 1486 population controls in south-west England in which subjects were interviewed personally about their smoking habits and their consumption of foods and supplements rich in retinol or carotene. Analyses were performed for 15 dietary variables, including intake of pre-formed retinol and carotene. There were significant associations (P< 0.01) with lung cancer risk for 13 of the variables, eight of which remained after adjustment for smoking. When the 15 variables were considered simultaneously, independent significant associations remained for 5: pre-formed retinol (increased risk), and fish liver oil, vitamin pills, carrots and tomato sauce (decreased risk). It is unlikely that all five associations represent biological effects, or that they can all be explained by residual confounding by smoking, or by biases. We conclude that there is at least one as yet unidentified factor that is causally related to lung cancer risk and of considerable importance in terms of attributable risk in this population.

Cancer patients' expectations of the role of family physicians in communication about complementary therapies.

OBJECTIVE: To explore cancer patients' experiences with and expectations of the role of family physicians in communication about complementary therapies. DESIGN: Focus group interviews. SETTING: British Columbia Cancer Agency and the University of Calgary. PARTICIPANTS: Sample of 14 cancer patients using complementary therapies comprising 3 focus groups (2 in BC and 1 in Alberta). RESULTS: The role of family physicians in discussing complementary therapies varied from being extraneous to patients' decision making to being a partner in making decisions about cancer treatments. Patients expected their physicians to be supportive, caring, kind and to show an interest in them. They also expected their physicians to be accepting and nonjudgmental regarding complementary therapy use and to reinforce a sense of hope. Most patients did not expect their doctors to have extensive knowledge about these therapies. All patients strongly felt the need to seek information themselves. In addition, they felt that believing in the type of therapies they were using was very important. CONCLUSION: Family physicians can play an important role in exploring and discussing complementary therapies with their patients. It is important that they are made aware of their patients' needs in this area.

Complementary therapy and cancer: decision making by patients and their physicians setting a research agenda.

An invitational meeting, entitled Complementary and Alternative Therapy: Decision Making by Cancer Patients and Their Physicians, brought together Canadian health care providers and researchers who had expertise in patient-physician communication with those who were knowledgeable about complementary therapy and cancer. The aim was to build on the existing knowledge base in both fields in order to determine the unanswered questions, the most important questions, and what methods can be applied for answering these questions. The interdisciplinary group employed a step-wise collaborative process to develop a suggested research agenda regarding decision making by physicians and their cancer patients regarding complementary therapy. The four themes identified are establishment of a registry for complementary therapy usage for cancer care; communication; outcomes measurement; and models of integration. It is hoped that these themes will be considered worthy of support by funding agencies and worthy of investigation by researchers.

Detection and structural characterization of ras oncoprotein-inhibitors complexes by electrospray mass spectrometry.

MS based methodology employing electrospray ionization (ESI) is described for the detection of ternary complexes in which SCH 54292 or SCH 54341 and GDP are noncovalently bound to oncogenic ras protein. The observed molecular weights of 19,816 and 19,570 Da confirmed the presence of noncovalent complexes of ras-GDP-SCH 54292 and ras-GDP-SCH 54341, respectively. We have also performed selective chemical modification of lysine residues of the ras protein complex followed by enzymatic digestion and on-line LC-ESI MS peptide mapping to determine protein-drug binding topography. There was a good correlation between nucleotide exchange inhibition as determined by the enzyme assay and evidence of complex formation as determined by MS.

Prevention of cancer: practical prospects.

The discovery of some 40 specific factors that have caused cancer in humans has demonstrated conclusively that many fatal cancers are capable of being prevented. These known factors are responsible for less than half all fatal cancers in all countries and much less in most; but there is good evidence, derived from the variation in the incidence of cancer in different communities, in different countries, and at different times that in many countries it may be possible to prevent 80% of all cancers or even more. The practical problems facing each country are different. Not only are the types of cancer different that need most urgently to be prevented, but so are the social and economic conditions that permit or constrain the introduction of preventive measures. Well-understood measures are summarized and the prospects for others that are less established or as yet untried are discussed, including the use of low-tar cigarettes, dietary modification, and anti-viral vaccines.

A retrospective study of renal cancer with special reference to coffee and animal protein consumption.

Interviews were obtained with 106 patients with adenocarcinoma of the renal parenchyma, 33 patients with carcinoma of the renal pelvis and 139 individually matched control patients. Comparison of the cancer patients with the control patients showed no evidence of a positive association between either type of renal cancer and coffee or animal protein consumption. Carcinoma of the renal pelvis was associated positively with cigareete consumption (relative risk estimate 1-8) and the daily consumption of analgesic tablets was more frequent in patients with cancer of the renal parenchyma than in their matched controls (14-2% compared with 1-9%,P less than 0.005). It appeared likely that the latter relationship was non-causal.

Clinical trial of a new carbenoxolone analogue (BX24), zinc sulphate, and vitamin A in the treatment of gastric ulcer.

The effects of a new carbenoxolone analogue (BX24), zinc sulphate, and vitamin A on the healing of gastric ulcer have been assessed in a multifactorial clinical trial conducted in out-patients treated for four weeks.Forty-eight patients completed the trial. Three groups of eight patients were given respectively 300, 600, and 1 200 mg of BX24 daily and were compared with 24 patients who were given 300 mg of carbenoxolone sodium daily. The size of the ulcer niche was reduced on average by 14.6% in the eight patients given BX24 300 mg daily, by 47.6% in the patients given 600 mg daily, and by 51.0% in the patients given 1 200 mg daily. In the patients given carbenoxolone the size of the niche was reduced by 68.9%. These results were compared with those obtained previously with carbenoxolone and inert tablets and it was concluded that BX24 is without clinically useful effect in the doses used. Eleven of the 24 patients (46%) treated with carbenoxolone sodium developed side effects due to fluid retention and electrolyte disturbances. None of the patients given BX24 experienced such effects. In addition to carbenoxolone or BX24, 24 patients were given zinc sulphate, 660 mg daily, and in 24 patients these tablets were withheld. Among the patients given carbenoxolone the reduction in the size of the niche was much the same irrespective of whether or not the patients received zinc sulphate. Among the 12 patients given BX24 with zinc sulphate the ulcer healed completely in four and, on average, the size of the niche was reduced by 53.5%, compared with 21.9% in the 12 patients given BX24 alone. This difference is not statistically significant but the possibility of a beneficial effect from zinc is not excluded. No side effects attributable to zinc were observed.Twenty-four patients were also given vitamin A, 50 000 units daily, and in 24 patients the vitamin was withheld. No evidence was obtained to suggest that vitamin A had any beneficial effect on the healing of gastric ulcer.