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The study investigated differences in lung cancer mortality risk between social classes.

Altogether 656 male lung cancer cases and 1312 age and sex matched controls were interviewed between 1976 and 1981 in a case-control study of cigarette smoking habits and lung cancer in Glasgow and the West of Scotland, an area with the highest recorded incidence in the world. The relative risk of lung cancer increased significantly for smokers whose consumption was below 20 cigarettes per day but did not rise significantly in those who smoked more than 20 cigarettes per day. Other smoking characteristics such as inhalation and tar yields of brands smoked did not explain this finding. Additionally, the relative risks observed at all levels of cigarette consumption were low in comparison with those in the published literature. By constructing an index of cigarette exposure which included the tar yields of brands smoked, an assessment of the risk of lung cancer in relation to tar exposure independent of amount smoked was derived. Only in smokers of less than 15 cigarettes per day was there a statistically significant reduction in risk of lung cancer associated with lower levels of tar yield.

A general population cohort of 7055 men aged 45-64 and resident in Renfrew and Paisley, two urban burghs in the West of Scotland, has been followed for 10 1/2 years. Analysis of the cigarette smoking and lung cancer (incidence and mortality) relation has been undertaken in order to establish whether unusual results found in a case-control study of cigarette smoking and lung cancer in the adjacent city of Glasgow could be confirmed. Lung cancer incidence and mortality rates increased markedly for exposure categories up to an average consumption of 15-24 cigarettes per day. Above this level the rates increased only marginally. Expressing these rates relative to that estimated for the never-smoked group and comparing them with the relative risks estimated in the case-control study revealed a similarity in terms of both the shape and the level of the dose-response relation. Comparison of the lung cancer rates found in this cohort with those observed in other cohort studies in the literature (UK doctors, US Veterans, and American Cancer Society volunteers) suggested that the West of Scotland rates were substantially higher at all levels of cigarette exposure.

The relationship between peptic ulceration and gastric carcinoma has been examined using data from two large autopsy surveys. The first consisted of over 13,000 autopsies performed in a single hospital over a 20-year period and analysed retrospectively; the second was a prospective series of over 7000 autopsies carried out at 17 centres during a single year. In both, a lower than expected occurrence of coexistent gastric cancer was found in subjects with pathologic evidence of active or past gastric and duodenal ulceration. A statistical association between chronic gastric ulcer and lung cancer was noted. This study has failed to identify an increased risk of gastric carcinoma in patients with chronic gastric ulcer.

In all 8353 women and 7058 men aged 45-64 took part in the Renfrew/Paisley survey in 1972-1976. They formed a prospective cohort study of a general population in the West of Scotland; an area with high ischaemic heart disease (IHD) mortality rates. The objective of this study was to investigate three indicators of pre-existing IHD and determine how they predicted subsequent IHD mortality in females compared with males.

The relationship between pre-operative levels of carcino-embryonic antigen (CEA), resectability of the primary tumour, the extent of tumour spread and subsequent survival was studied in 333 patients with colorectal cancer. Twenty-five per cent of patients undergoing ‘curative’ resection had elevated CEA levels compared with fifty-six per cent of patients receiving palliative treatment. Twenty-five per cent of patients with Dukes B or C tumours had elevated pre-operative CEA levels compared with seventy per cent of patients with stage D disease. In patients undergoing ‘curative’ resection there was no correlation between pre-operative CEA levels and subsequent survival. In patients undergoing palliative resection, elevated pre-operative CEA levels were associated with poor survival. Although pre-operative levels of CEA reflect the extent of the underlying disease process, estimations of pre-operative CEA levels are of limited value in predicting patients with a poor prognosis following curative resection for colorectal carcinoma.

A prospective study was carried out of 404 patients with colorectal cancer who were followed up for a mean period of 42 months. Macroscopic extramural tumour invasion was found at laparotomy in 46 patients undergoing apparently curative surgery and the survival rate was significantly reduced in these patients. The site of primary tumour in the colon or rectum did not influence the incidence of local tumour spread, but local invasion was related to the incidence of lymph node metastases and histological grading of the tumour. A staging classification has been proposed based not on lymphatic metastases, but on the extent of local tumour penetration. This modified staging system combines the operative findings with pathological grading of the tumour and emphasizes the prognostic significance of local tumour invasion.

In recent years a strong case has been made in support of a viral aetiology for at least some primary hepatocellular carcinoma (PHC) in areas of low incidence. By pooling routinely collected cancer registration and infection data, study of the relationship between hepatitis B virus (HBV) infection and the incidence of PHC in Scotland over the period 1972–1985 has confirmed this view. Over this period the incidence of PHC in men increased, there was a relationship between the incidence of notification of HBV infection and that of hepatocellular carcinoma in different parts of the country, and an increased risk attached to those chronically infected with the virus. Given the recent introduction of lower cost yeast derived vaccines, there may now be more scope for prevention both of primary liver cancer and of other liver disease.

An account is given of the development of a multiphasic screening unit designed to detect susceptibility to and early evidence of cardiorespiratory disease in apparently healthy populations. The procedure is based on an augmented mass miniature radiography procedure costing £2.65 for each person examined. Some preliminary results are presented from the first prospective study of 4, 681 subjects re-examined after more than two years. The prevalence of cardiorespiratory abnormality and 271 deaths representing annual mortality rates of 10.0 per thousand in males and 3.8 per thousand in females respectively, are described. A comparison is made of certain measurements obtained at the first screening examination of male decedents and a random sample of survivors; and the use of the likelihood ratio, a statistical procedure derived from multivariate analysis, is suggested as a prognostic index of incipient cardiorespiratory disease worthy of further study. At present theoretical errors of up to 10 per cent exist in predicting survival of men under fifty and of up to 12 per centin predicting death for men over fifty. Larger errors may be present in the prediction of death in men under fifty and survival of men over fifty. The implication of these errors is discussed in relation to their consequence for the patient and their place in the validation of future surveys.