Is risk of Kaposi's sarcoma in AIDS patients in Britain increased if sexual partners came from United States or Africa?

OBJECTIVE

To determine whether the risk of Kaposi's sarcoma in patients with AIDS is increased by sexual contact with groups from abroad with a high incidence of Kaposi's sarcoma.

DESIGN

Analysis of risk of Kaposi's sarcoma in patients with AIDS, according to country of origin of their sexual partners.

SETTING

United Kingdom.

PATIENTS

2830 patients with AIDS reported to the Communicable Disease Surveillance Centre and the Communicable Disease (Scotland) Unit up to March 1990, of whom 566 had Kaposi's sarcoma.

MAIN OUTCOME MEASURES

Percentage of patients with AIDS who had Kaposi's sarcoma.

RESULTS

537 of 2291 homosexual or bisexual men (23%) with AIDS had Kaposi's sarcoma; 10% (14/135) of the men and women who acquired HIV by heterosexual contact had Kaposi's sarcoma. None of the 316 subjects who acquired HIV through non-sexual routes had Kaposi's sarcoma. Kaposi's sarcoma was more common among homosexual men whose likely source of infection included the United States (171/551, 31%) or Africa (9/34, 26%) than among those infected in the United Kingdom (119/625, 19%) (p less than 0.05).

CONCLUSION

The data suggest that Kaposi's sarcoma is caused by a sexually transmissible agent which was introduced into the British homosexual population mainly from the United States [corrected].

The prevalence and characteristics of congenital pigmented lesions in newborn babies in Oxford

Melanocytic naevi (MN) are recognised risk factors for malignant melanoma but the epidemiology of MN is poorly understood. Some MN are present at birth and the study of congenital lesions is an important first step toward understanding the development of MN in early life. In this study, the prevalence and characteristics of congenital pigmented lesions were documented in 1012 White caucasian newborn babies at a maternity hospital in Oxford. Only 12 babies (1.2%) were found to have pigmented skin marks and each of these had only one lesion and no other abnormalities. MN were identified with certainty in only five babies (0.5% of the population; 95% CI, 0.06%-0.93%) thus confirming the relatively low prevalence of this lesion. Four of the MN were noted to be 'small' (less than 15 mm diameter) and all five were less than or equal to 20 mm in diameter. In other respects, the MN displayed a diversity of features. Of the other lesions there were two Mongolian blue spots, one melanocytic pustule, one 'probable' MN and three unusual skin marks where the diagnosis was uncertain but considered unlikely to be MN. During the course of the study, examinations were also carried out incidentally on 39 non-White babies. Twenty-two of these were noted to have Mongolian spots (57%) and three had other pigmented lesions (8%).

Thymus cancer epidemiology in England and Wales

Thymus cancer epidemiology has been little investigated, but recent clinical studies have suggested an association with the Epstein-Barr virus. We studied thymus cancer incidence 1963-83 and mortality 1959-86 in England and Wales, using data from the National Cancer Register and national mortality files. Mean age-standardised incidence rates of the tumour were 0.72 per million per annum for males and 0.64 for females; mortality rates were about half of this: 0.43 for males and 0.29 for females. There was no significant change in rates over time, nor any consistent pattern of risk by region of residence. Birth cohort analysis of mortality showed in each sex, lowest risk for persons born during the Second World War. The age distribution of the tumour was unusual: a progressive rise in both incidence and mortality rates occurred in each sex at ages up to 60-69, at which there was a striking peak, more marked for males and for incidence data, with a sharp decline thereafter. Immigrants from China and Cyprus had significantly high proportional registration ratios, but based on small numbers.

Occupation and malignant melanoma: a study based on cancer registration data in England and Wales and in Sweden

An analysis of the incidence of malignant melanoma according to occupation is presented using data from two national cancer registries. The data relate to 3991 cases of cutaneous malignant melanoma, 662 cases of ocular melanoma, and 179 cases of noncutaneous, non-ocular melanoma in subjects aged 15-64 in England and Wales diagnosed from 1971 to 1978 and to 5003 cases of cutaneous malignant melanoma diagnosed from 1961 to 1979 in Sweden in subjects born between 1896 and 1940. Professional workers of both sexes in both countries experienced an excess incidence of cutaneous malignant melanoma. An excess of ocular melanoma and of non-cutaneous, non-ocular melanoma also existed for this group in England and Wales. Pharmacists, medical doctors, and dentists had a high incidence of cutaneous melanoma in both countries and were represented three times when listing the top 20 occupations in both countries and both genders. Combining the data from cutaneous malignant melanoma over both sexes and both registries the occupations with the highest incidence ratios (expressed as a percentage) were: airline pilots, incidence ratio (IR) = 273, (95% confidence limits 118-538); finance and insurance brokers IR = 245 (140-398); professional accountants IR = 208 (134-307); dentists IR = 207 (133-309); inspectors and supervisors in transport IR = 206 (133-304); pharmacists IR = 198 (115-318); professionals not elsewhere classified IR = 196 (155-243); judges IR = 196 (126-289); doctors IR = 188 (140-248); university teachers IR = 188 (110-302); and chemists IR = 188 (111-296). No particular exposure in the workplace seemed to link these groups and only a few worked in high technology environments. Many of the highest risk groups have in common a high level of education. In England and Wales and in Sweden this might correlate particularly with foreign travel abroad was more unusual than it is now, but evidence on present and past exposure to sun by occupation is needed to clarify the reasons for the association.

Interpretation of England and Wales cancer mortality data: the effect of enquiries to certifiers for further information

For some death certificates in England and Wales the cause information coded and published in national data is not that initially submitted by the certifier, but instead derives from a subsequent enquiry to the certifier for further information. These enquiries can lead to substantial artefacts in secular mortality data, and also to substantial non-comparability between mortality data for special study groups, such as subjects in cohort studies, and published mortality data. A description of current enquiry policy relevant to cancers, and changes in this policy over recent years is given to aid interpretation of mortality data. The effects on secular data of changes in enquiry policy are illustrated. At 4-digit level of the ICD, changes in enquiry policy can alter published mortality rates by several hundred per cent. At 3-digit level the greatest effects of enquiries at present are to increase the number of deaths coded to cancer of the eye by 35% and cancer of the body of the uterus by 31%; cancers of the thymus, heart and mediastinum are increased by 18%, and pleural cancer by 17%, while decreases of more than 10% are caused for several 'other' and 'unspecified' rubrics, and a decrease of 6% for deaths coded to melanoma.

Testis cancer: post-natal hormonal factors, sexual behaviour and fertility

The relationship of risk of testis cancer, and subdivisions of the tumour by histology, to variables which may be related to hormonal status, sexual behaviour and fertility was investigated in data from a case-control study with 259 cases and 2 sets of controls. No consistent association was found between testis cancer risk and age at puberty, need to shave, obesity, alcohol intake, animal fat intake, and sexual behaviour. There was a significant excess of seminomas in very tall men. Testis cancer cases showed lower fertility than controls according to various measures, but this reflected the greater frequency of cryptorchidism among cases compared to controls. Among non-cryptorchid subjects there was no clear evidence that infertility was associated with risk of testis cancer.

Fluorescent lights, ultraviolet lamps, and risk of cutaneous melanoma

Exposure to solar radiation is increasingly being associated with a risk of cutaneous melanoma, and some risk has also been attributed to exposure to fluorescent lights. The risk of cutaneous melanoma associated with exposure to some sources of artificial ultraviolet radiation was examined in a case-control study in a Scottish population with fairly low exposure to natural ultraviolet radiation. The risk was not significantly or consistently raised for exposure to fluorescent lights at home or at work. The use of ultraviolet lamps and sunbeds, however, was associated with a significantly increased risk (relative risk = 2.9; 95% confidence interval 1.3 to 6.4), and the risk was significantly related to duration of use. The risk was particularly raised among people who have first used [corrected] ultraviolet beds or lamps more than [corrected] five years before presentation (relative risk = 9.1; 95% confidence intervals 2.0-40.6), in whom it was significantly related to cumulative hours of exposure. The risks associated with exposure to ultraviolet lamps and sunbeds remained significant after adjustment for other risk factors for melanoma.

Is the incidence of testis cancer related to trauma or temperature?

The position of the testes reduces their temperature but makes them vulnerable to trauma. Patients with testis cancer frequently report prior testicular trauma, but this trauma may have triggered diagnosis of the tumor rather than been aetiological. In this study, the frequencies of various prior traumatic and temperature exposures in 259 patients with testis cancer were compared with their frequencies in two sets of control patients who did not have testis cancer. Particular effort was made to prevent bias. Testis cancer was not significantly associated with any temperature or trauma exposure and the confidence limits of the findings excluded substantially raised risks. The evidence suggests that raised temperatures and traumas commonly encountered in everyday life are not important risk factors for testis cancer. The possible aetiological roles of extreme trauma sufficient to cause atrophy, and of the trauma and raised temperature which can occur in cryptorchidism, however, need investigation by other methods.

Site-specific melanocytic naevus counts as predictors of whole body naevi

Counts of melanocytic naevi of 2 mm or greater diameter on all body sites were conducted in 197 Caucasian adults in Scotland. Mean naevus numbers were greater in young than in older adults, and in females than in males. Naevus counts on the upper limbs, lower limbs, and trunk were strongly and significantly correlated with each other and with whole body counts. Thus, where whole body counts are impractical, counting naevi at any of these individual sites should provide a satisfactory method for studying naevus distribution in large populations.

Occupational associations of testicular cancer in south east England

The relation of occupation to the risk of testicular cancer was investigated in a case-control study using data from the files of the South Thames Cancer Registry. Risks by age and histology subdivisions of the tumour were investigated since there is epidemiological evidence of differences in aetiology between these subdivisions but no previous systematic study of occupational risks by age and histology. Analyses were conducted comparing 1605 cases of testicular cancer incident in the region during 1958-77 with 7187 controls selected from other cancers incident in men in the region during the same period. The greatest risks of testicular cancer overall were for administrators and managers, sales workers, professional and allied workers, electrical workers, and clerical workers; these occupations were generally also at high risk of subdivisions of the tumour age and histology. Risk of testicular cancer overall and in each age and histology subgroup was greater in men of high than of low occupation based social class. Occupations with high risk of testicular cancer for their social class are of particular interest for further investigation of possible occupational risk factors; occupations with this characteristic for testicular cancer overall or in subdivisions in the present and some previous data are farmers, electrical workers, and paper and printing workers.

The value of England and Wales congenital malformation notification scheme data for epidemiology: male genital tract malformations

Data from the England and Wales national congenital malformation notification scheme were examined for associations of male genital tract malformations. For some of the malformations comparison of notification rates with the literature suggested gross undernotification. There was also evidence suggesting bias: examination of the relationships of the malformations to birth weight, maternal parity, and maternal age at delivery showed some highly significant trends in risk, most of which were at variance with findings in the literature, and several potential mechanisms for bias could be adduced. Direct investigation is needed, for this and other similar data sets, of the extent and mechanisms of biased undernotification.

The risk of malignant melanoma, internal malignancy and mortality in xeroderma pigmentosum patients

Mortality and malignancy were studied in a series of 32 patients with xeroderma pigmentosum presenting during the period 1950-84. Twenty-nine of the patients were followed to the end of 1984 using the National Health Service Central Register, and hospital case records and correspondence with referring physicians; three patients had incomplete follow-up. Three of the patients developed malignant melanoma during follow-up, but none developed internal malignancy. Two males and one female died [standardized mortality ratio (SMR) = 971, P less than 0.05, for males; SMR = 1931, not significant, for females]. All three deaths were from non-malignant causes: severe neurological involvement with terminal infection. This high mortality from neurological complications in xeroderma pigmentosum patients contrasts with previously reported mortality, particularly from actinic-induced cutaneous tumours.

Melanocytic naevi and melanoma: an epidemiological perspective

There is growing evidence that individuals at high risk of cutaneous melanoma can be identified by the use of simple measures of benign melanocytic naevi--raised risk occurring in persons who have large numbers of naevi, or naevi with atypical clinical features. Very high risk of melanoma appears to exist in two rare groups: persons with dysplastic naevi whose families include at least two individuals who have had melanoma, and persons with giant congenital naevi. Risks of melanoma in other individuals with dysplastic naevi and in persons with small congenital naevi have not yet been quantified. Much of the published work on risk of melanoma in relation to naevi has been based on clinical series or assemblage of case reports, with great potential for bias. In such studies, naevi have often been classified into dichotomies or syndromes originally defined for pathological or clinical purposes, frequently using poorly reproducible criteria. Case-control and cohort studies of the relationship of naevi to melanoma are needed, which use reproducible criteria and designs minimizing bias, and which examine risk in relation to graded clinical and histological measures of naevi.

Prenatal and familial associations of testicular cancer

In a case-control study of testis cancer 259 cases with testicular cancer, 238 controls treated at radiotherapy centres and 251 non-radiotherapy hospital in-patient controls were interviewed about some possible prenatal and familial risk factors for the tumour. For firstborn men, the risk of testis cancer increased significantly according to maternal age at the subject's birth, and this effect was most marked for seminoma. The association with maternal age was not apparent for cases other than firstborn. The risk of testis cancer was also significantly raised for men from small sibships and of early birth order. These results accord with the theory that raised maternal levels of available oestrogen during the early part of pregnancy are aetiological for testicular cancer in the son, although other explanations are possible; there is evidence that seminoma risk may particularly be affected.

Relation between phenotype and banal melanocytic naevi

In a study of risk factors for the development of melanocytic naevi in relation to the pathogenesis of malignant melanoma 197 white adults were examined by four dermatologists and naevus counts correlated with several other features. Highly significant associations were found between large numbers of banal acquired melanocytic naevi and the ability to tan easily without burning (skin types 3 and 4; relative risk 4.6), brown or hazel eyes (relative risk 3.5), green or grey eyes (relative risk 3.5) and brown or black hair (relative risk 3.7). No significant associations with numbers of naevi were shown for parity or use of oral contraceptives or other steroid hormones. This is the first study to find any relation between melanocytic naevi and phenotypic factors in a white population.

Testicular cancer and antecedent diseases

A case-control study of the aetiology of testicular cancer was conducted using information obtained by interview and from case-notes of 259 cases with testicular cancer and two sets of control patients -238 men with diagnoses other than testicular cancer attending the same radiotherapy centres as those attended by the cases, and 251 hospital in-patients not attending radiotherapy departments. Logistic regression analyses were performed, after stratifying by age and region of residence, to estimate the relative risks (RRs) associated with various aspects of prior medical history. The risk of testicular cancer was found to be raised for men with a history of cryptorchidism (RR based on comparison with all controls = 6.3; P less than 0.001), inguinal hernia (RR = 1.6; P = 0.14), mumps orchitis (RR = 12.7; P = 0.006), atopy (RR = 1.8; P = 0.03), and meningitis (RR = 3.0; P = 0.21). Inguinal herniorrhaphy before the age of 15 years was particularly a risk factor for seminoma, whereas the relative risks were similar for seminoma and teratoma for the other factors. The results add to the growing evidence that congenital abnormalities involving the process of testicular descent and closure of the processus vaginalis are risk factors for testicular cancer, and that some types of testicular damage later in life may also be important. The findings of associations with previous atopy and certain infections suggest a possible second aetiological mechanism - that immunological abnormalities may be associated with an increased risk of testis cancer.

Seasonal variations in cryptorchidism

The month of birth of boys undergoing orchidopexy in the Oxfordshire Health District during the years 1974-83 was analysed. A significant seasonal variation with a peak in April was found for those boys operated upon by paediatric surgeons at a young age (0-4). Possible causes of this variation and its relationship to the aetiology of cryptorchidism are discussed.

Benign melanocytic naevi as a risk factor for malignant melanoma

Examination of 180 patients with cutaneous malignant melanoma and 197 control patients in a case-control study showed that the risk of melanoma is strongly related to numbers of benign melanocytic naevi (moles). Some unusual features of naevi--a diameter exceeding 7 mm, colour variation, and irregular lateral outline--also showed a strong association with the risk of melanoma, but the relation of numbers of naevi to risk was present even in the group of patients whose naevi had none of these unusual features. Biopsy of clinically atypical naevi from several of the patients at highest risk generally did not show dysplastic histology. Thus a group of people at high risk of melanoma may be identified by using simple clinical assessment of naevi.

Seasonality of presentation of cutaneous melanoma, squamous cell cancer and basal cell cancer in the Oxford Region

The seasonality of presentation of 1019 skin melanomas in Oxford Region 1952-1975, and of 1,523 squamous cell and 4,865 basal cell skin cancers in the region 1967-1975, were analysed using data from the Oxford Cancer Registry. For males and for females, for each of the histologies there was a peak of presentations during July to September. In further subdivisions of the data by age and by skin site, a summer or autumn peak was generally present except where numbers of cases were small. Amplitude of seasonality did not show consistent differences by histology, sex, or skin site, but for both melanoma and squamous cell cancer amplitude was greater for persons aged under 55 years than for older persons. There was no substantial seasonality for presentations of cancers of all non-skin sites in the region. The seasonality of presentation of skin cancers appeared not to be mainly an artefact of the cancer registration process or of organisational aspects of medical care attendance, and only a small proportion of it could be explained as an artefact of the longer term increase in registrations of these cancers. The visibility of skin cancers might have lead to seasonal variation in rapidity of presentation to medical care, for instance for social reasons, or the results might reflect a short induction period effect of exposure to a seasonal insult, perhaps sun radiation, on the aetiology, growth or symptoms of skin cancers; for melanoma there is previous evidence suggesting a short induction period aetiological effect of sun radiation.