PubMed Health⌕ Search

Biomedical subjects

R H Cowdell

Publications and source records attributed to R H Cowdell.

15 recordsLinked to original sources

Nasal cancer in England and Wales: an occupational survey.

A national survey of the incidence of nasal cancer in England and Wales during the period 1963-7 with special reference to occupation confirmed the well-known increases in incidence of nasal cancer in cabinet makers and wood machinists, together with the absence of any significant increase in carpenters and joiners, and the increases in boot and shoe operatives and repairers, and in nickel smelters in South Wales. The significant excesses of cases found among coalminers, furnacemen in the gas, coke, and chemical industry, and furnacemen and labourers in foundries may be associated with exposure to coal and coke dust or may be spurious. No excess of nasal cancer was found among male textile workers. Excesses of uncertain significance were found among tailors and dressmakers, bakers and pastry cooks, and printers. Apart from the well-known relationships between adenocarcinoma and work in the furniture and footwear industries there is no definite indication in this survey of any association between a particular histological type of nasal tumour and occupation in England and Wales.

Adolescent↗

Characteristics of women with dysplasia or carcinoma in situ of the cervix uteri.

To identify risk factors for various cervical abnormalities, 237 women with abnoromal cervical smears and 422 control women were interviewed. Cervical biopsy specimens taken from the patients with abnormal smears were reviewed according to standard criteria by one pathologist and classified as follows: 65 carcinoma in situ, 81 severe dysplasia, 44 mild dysplasia and 47 normal histology. Factors associated with risk of mild dysplasia, severe dysplasia and carcinoma in situ were similar to those previously identified for invasive carcinoma, and included age at first intercourse, multiple sexual partners and pregnancy outside marriage. Analysis to disentangle correlated factors revealed that number of sexual partners exerted effects independently of age at first intercourse, whereas the reverse was not true. This finding fails to support suggestions that adolescence is a period when the cervix is most vulnerable to the effects of sexual behaviour. Other factors relating to risk of cervical abnormalities were smoking and use of oral contraceptives. It was not possible to show that these relationships were incidental, but further investigation is required to establish whether they are causal.

Adolescent↗

Adenocarcinoma of the uterine cervix: cytological evidence of a long preclinical evolution.

Adenocarcinoma of the cervix occurred in 13 women who had previously had "negative" cervical smears. These smears were reviewed, and abnormalities were found in six cases, the intervals ranging from two to eight years. It is concluded that adenocarcinoma, like squamous carcinoma of the cervix, can have a prolonged evolution during which it is cytologically detectable.

Adenocarcinoma↗

A quantitative comparison between normal and carcinomatous squamous epithelia of the uterine cervix.

The object of this study was to measure some of the differences between normal squamous epithelial cells and cells from invasive squamous carcinoma of the uterine cervix. A total of 107 patients were studied; only those specimens which when assessed by a histopathologist were thought to show classic normal features or undoubted invasive carcinoma were included in the quantitative analysis. In addition, any specimens which at the electron microscope level, showed faulty sampling or preparation were discarded, leaving us with 16 carcinoma and 15 normal specimens for detailed study.The nuclei of tumour cells had a greater area than those of normal cells; histograms of the size distribution of nuclei showed a distinctly different pattern in the 2 groups. Tumour cells had fewer ribosomes in each cubic micron of cytoplasm than had the normal cells and showed a reduction in the amount of intercellular space; in addition, the malignant cells had a smaller surface density and fewer tonofibrils in their cytoplasm. Some tumour cells had a smaller percentage of cell membrane specialized as desmosomes than the corresponding normal cells but all tumour cells had desmosomes of shorter length than normal.Discriminatory analysis, carried out with the help of a computer, allowed all of these variables to be assessed with respect to each other in order to arrive at a numerical score for each specimen. When expressed graphically, these scores showed that the populations of normal and carcinomatous cells fell into 2 separate groups. The significance of these results is discussed.

Carcinoma, Squamous Cell↗

Nasal cancer in the Northamptonshire boot and shoe industry.

A survey of the incidence of nasal cancer in Northamptonshire during the period 1953 to 1967 is reported. Of the 46 patients with nasal cancer ascertained during the 15-year period 21 (19 males and 2 females) had been employed at some time in the boot and shoe industry. Five other cases diagnosed either before 1953 or after 1967 in persons who had worked in the boot and shoe industry in Northamptonshire were ascertained from various sources.The incidence of nasal cancer (all histological types considered together) was significantly higher in male boot and shoe operatives in Northamptonshire than in males of all occupational classes in the Cancer Register areas selected for comparison and in males working in other occupations in Northamptonshire. The excess incidence has recently given rise to the occurrence of between 1 and 2 new cases per annum in the Northamptonshire boot and shoe industry.The cases within the Northamptonshire industry occurred almost entirely in the relatively small number of workers who are exposed to the dust of the materials used in the manufacture of footwear.Possibly there are two carcinogenic factors in the industry-one related to the production of nasal adenocarcinoma, and the other to squamous and possibly other types of carcinoma in the nasal cavity and sinuses. This requires further study. Our best estimate of the latent period for the adenocarcinoma cases was 54.6 years, which is substantially longer than for the patients with squamous, transitional, and anaplastic tumours (41.7 years). We have no evidence to answer the question whether the facts are still present in the industrial environment, though undoubtedly the standards of hygiene in the industry has improved substantially since these men were first exposed.There is probably an increased risk of nasal adenocarcinoma in the footwear repairing industry, but this requires further study. Our evidence suggests that snuff taking should be considered as a possible contributory factor in both industrial and non-industrial nasal cancer.A survey of the footwear manufacturing and repairing industry is recommended regarding cancer of the respiratory tract. Further attempts should be made to minimize the inhalation of dust. The case for the prescription of nasal cancer in the footwear industry should be considered.

Adenocarcinoma↗

Preliminary observations on the histochemistry of the cell surface of carcinoma of the cervix.

Histochemical studies on the cell surface and intercellular matrix of normal cervical epithelium, and squamous cell carcinomata have shown the mucosubstances present may be symbolized by the descriptive formula:C(G) mucosubstance; B 3.5; A 2.5 (0.6m MgCl(2)); T; S.This indicates that sulphate groups are absent and that the intercellular matrix and cell coat are rich in hyaluronic and sialic acids or closely related compounds. These may be important in masking the antigenic expression of the tumour cells.We have not been able to detect any alteration in the mucosubstances at 7 days following radium treatment.

Antigens↗