Increased stomach cancer risk following radiotherapy for testicular cancer

BACKGROUND

Abdominal radiotherapy for testicular cancer (TC) increases risk for second stomach cancer, although data on the radiation dose-response relationship are sparse.

METHODS

In a cohort of 22,269 5-year TC survivors diagnosed during 1959-1987, doses to stomach subsites were estimated for 92 patients who developed stomach cancer and 180 matched controls. Chemotherapy details were recorded. Odds ratios (ORs) were estimated using logistic regression.

RESULTS

Cumulative incidence of second primary stomach cancer was 1.45% at 30 years after TC diagnosis. The TC survivors who received radiotherapy (87 (95%) cases, 151 (84%) controls) had a 5.9-fold (95% confidence interval (CI) 1.7-20.7) increased risk of stomach cancer. Risk increased with increasing stomach dose (P-trend<0.001), with an OR of 20.5 (3.7-114.3) for ⩾50.0 Gy compared with <10 Gy. Radiation-related risks remained elevated ⩾20 years after exposure (P<0.001). Risk after any chemotherapy was not elevated (OR=1.1; 95% CI 0.5-2.5; 14 cases and 23 controls).

CONCLUSIONS

Radiotherapy for TC involving parts of the stomach increased gastric cancer risk for several decades, with the highest risks after stomach doses of ⩾30 Gy. Clinicians should be aware of these excesses when previously irradiated TC survivors present with gastrointestinal symptoms and when any radiotherapy is considered in newly diagnosed TC patients.

Pancreatic cancer risk after treatment of Hodgkin lymphoma

BACKGROUND

Although elevated risks of pancreatic cancer have been observed in long-term survivors of Hodgkin lymphoma (HL), no prior study has assessed the risk of second pancreatic cancer in relation to radiation dose and specific chemotherapeutic agents.

PATIENTS AND METHODS

We conducted an international case-control study within a cohort of 19 882 HL survivors diagnosed from 1953 to 2003 including 36 cases and 70 matched controls.

RESULTS

Median ages at HL and pancreatic cancer diagnoses were 47 and 60.5 years, respectively; median time to pancreatic cancer was 19 years. Pancreatic cancer risk increased with increasing radiation dose to the pancreatic tumor location (Ptrend = 0.005) and increasing number of alkylating agent (AA)-containing cycles of chemotherapy (Ptrend = 0.008). The odds ratio (OR) for patients treated with both subdiaphragmatic radiation (≥10 Gy) and ≥6 AA-containing chemotherapy cycles (13 cases, 6 controls) compared with patients with neither treatment was 17.9 (95% confidence interval 3.5-158). The joint effect of these two treatments was significantly greater than additive (P = 0.041) and nonsignificantly greater than multiplicative (P = 0.29). Especially high risks were observed among patients receiving ≥8400 mg/m(2) of procarbazine with nitrogen mustard or ≥3900 mg/m(2) of cyclophosphamide.

CONCLUSION

Our study demonstrates for the first time that both radiotherapy and chemotherapy substantially increase pancreatic cancer risks among HL survivors treated in the past. These findings extend the range of nonhematologic cancers associated with chemotherapy and add to the evidence that the combination of radiotherapy and chemotherapy can lead to especially large risks.

Risk of treatment-related esophageal cancer among breast cancer survivors

BACKGROUND

Radiotherapy for breast cancer may expose the esophagus to ionizing radiation, but no study has evaluated esophageal cancer risk after breast cancer associated with radiation dose or systemic therapy use.

DESIGN

Nested case-control study of esophageal cancer among 289 748 ≥5-year survivors of female breast cancer from five population-based cancer registries (252 cases, 488 individually matched controls), with individualized radiation dosimetry and information abstracted from medical records.

RESULTS

The largest contributors to esophageal radiation exposure were supraclavicular and internal mammary chain treatments. Esophageal cancer risk increased with increasing radiation dose to the esophageal tumor location (P(trend )< 0.001), with doses of ≥35 Gy associated with an odds ratio (OR) of 8.3 [95% confidence interval (CI) 2.7-28]. Patients with hormonal therapy ≤5 years preceding esophageal cancer diagnosis had lower risk (OR = 0.4, 95% CI 0.2-0.8). Based on few cases, alkylating agent chemotherapy did not appear to affect risk. Our data were consistent with a multiplicative effect of radiation and other esophageal cancer risk factors (e.g. smoking).

CONCLUSIONS

Esophageal cancer is a radiation dose-related complication of radiotherapy for breast cancer, but absolute risk is low. At higher esophageal doses, the risk warrants consideration in radiotherapy risk assessment and long-term follow-up.

Prevalence of Norwegian patients diagnosed with childhood cancer, their working ability and need of health insurance benefits

The object of this study was in a population-based material to investigate the prevalence of patients diagnosed with childhood cancer, and compared to the general population to assess working ability, yearly income and need for health insurance benefits in patients surviving at least five years after treatment for childhood CNS tumours or hematological malignancies. During the period January 1, 1970 to December 31, 2002 the prevalence in the Norwegian population of patients diagnosed with any childhood cancer increased from 12.2 (473/3 888 305) to 65.1 (2944/4 524 066) per 100 000 population. The proportion of survivors in need of any health insurance benefit was for CNS tumours 47.1% and for hematological malignancies 21.0%. The proportion in the age group 16-67 receiving disability pension for CNS tumours was 94/454 (20.7%) compared to 21/575 (3.7%) for patients treated for hematological malignancies (p < 0.001). Of patients given radiotherapy 25/70 (35.7%) received disability pension, compared to 90/959 (9.4%) in unirradiated patients, p < 0.001. Yearly income and working ability was particularly low for CNS tumour survivors. This study illustrates loss of working capability associated with pediatric cancer and treatment and long-term requirement of health insurance benefits.

Early life events and later risk of colorectal cancer: age-period-cohort modelling in the Nordic countries and Estonia

BACKGROUND

A lowering of colorectal cancer risk for the birth cohorts born around World War II (WWII) has previously been observed in Norway, a country which suffered some 20% caloric restriction during the war. The purpose of the study was to conduct a similar kind of analysis in the other Nordic countries and Estonia, which were also subjected to various degrees of energy restriction during WWII.

METHODS

All new cases of colorectal cancer in the Nordic countries and Estonia diagnosed between 40 and 84 years of age and born between 1874 and 1953, were collected from the national cancer registries. The incidence data were fitted to an age-period-cohort model.

RESULTS

A transient drop in the estimated colorectal cancer incidence rate was observed for the birth cohorts born around WWII in Estonia, together with a tendency of decreased risk in Sweden and Denmark.

CONCLUSION

The previously observed lowering of colorectal cancer risk for persons born during WWII in Norway also prevails in Estonia. Energy restriction is a possible explanation for these findings, since the countries suffered from varying nutritional conditions during the war. Exogenous factors acting during periods early in life may have an impact on later colorectal cancer risk.

Trends in Incidence of Brain and Central Nervous System Tumors in Norway, 1970–1999

The aim of this study was to investigate trends in the incidence of childhood and adult brain and central nervous system (CNS) tumors in Norway from 1970 through 1999. In this period, a total of 14,641 patients were diagnosed with a primary benign or malignant neoplasm of the brain and CNS. Age-adjusted incidence rates were reported together with results of loglinear regression and an age-period-cohort model based on the Poisson regression model. In children (<15 years), the proportion of brain and CNS tumors was 28.2% (1,042/3,697) of all new cancer cases compared with 2.8% in adults (13,599/492,237). The overall rate of brain and CNS tumors increased during the study period from 6.49 to 12.02 cases per 100,000 person-years. A trend of leveling off in incidence of most tumor categories during the study period was indicated with a possible continuing increase in the period 1995-1999, especially in the age group 0-4 years and in patients aged 60 years or more. Age and period together provided a satisfactory model in patients being <60 years of age and less completeness of diagnosis was found in males compared with females, possibly due to the distribution in males of more aggressive tumors.

Colorectal cancer survival trends in Norway 1958–1997

The purpose of this study was to examine the pattern of survival for colorectal adenocarcinoma (CRC), and to investigate the prognostic factors for the disease. In the analysis, 50993 cases of CRC aged 40-84 years, diagnosed between 1958 and 1997 in Norway, were included. Esteve's relative survival method was used, together with a time trend analysis, conducted by least-squares linear regression. Cox proportional hazards regression analysis was used to examine cause-specific mortality. Five-year relative CRC survival has increased by an estimated 3% per 5-year diagnostic period. In 1958-1962, relative survival was about 40% for both males and females, and increased to 56 and 60%, respectively, in 1993-1997. Rectal cancer had a higher cause-specific mortality (RR 1.26, 95% CI 1.22-1.30) than proximal colon (reference) and distal colon (RR 0.97, 95% CI 0.93-1.00 cancers), while females had a lower cause-specific mortality than males (RR 0.88, 95% CI 0.86-0.90). The increase in the relative survival rate in Norway is probably due to improved treatments and advanced diagnostics. Norway has a higher CRC survival rate than the EUROCARE average.

European health systems and cancer care

INTRODUCTION

Data on the survival of all incident cases collected by population-based cancer registries make it possible to evaluate the overall performance of diagnostic and therapeutic actions on cancer in those populations. EUROCARE-3 is the third round of the EUROCARE project, the largest cancer registry population based collaborative study on survival in European cancer patients. The EUROCARE-3 study analysed the survival of cancer patients diagnosed from 1990 to 1994 and followed-up to 1999. Sixty-seven cancer registries of 22 European countries characterised by differing health systems participated in the study. This paper includes essays providing brief overviews of the state and evolution of the health systems of the considered countries and comments on the relation between cancer survival in Europe and some European macro-economic and health system indicators, in the 1990s.

OVERVIEW OF THE EUROPEAN HEALTH SYSTEMS

The European health systems underwent a great deal of reorganisation in the last decade; a general tendency being to facilitate expanding involvement of the private sector in health care, a process which occurred mainly in the eastern countries (i.e. the Czech Republic, Estonia, Poland, Slovakia and Slovenia). In contrast, organisational changes in the northern European countries (i.e. Denmark, Iceland, Finland and Sweden) tended to confirm the established public sector systems. Other countries, including the UK and some southern European countries (i.e. England, Scotland, Wales, Malta and Italy) have reduced the public role while the systems remain basically public, at least at present. Our findings clearly suggest that cancer survival (all cancer combined) is related to macro-economic variables such as the gross domestic product (GDP), the total national (public and private) expenditure on health (TNEH) and the total public expenditure on health (TPEH). We found, however, that survival is related to wealth (GDP), but only up to a certain level, after which survival continues to be related to the level of health investment (both TNEH and TPEH). According to the Organisation for Economic Co-operation and Development (OECD), the TNEH increased during the 1990s in all EUROCARE-3 countries, while the ratio of TPEH to TNEH reduced in all countries except Portugal.

CONCLUSIONS

Cancer survival depends on the widespread application of effective diagnosis and treatment modalities, but our enquiry suggests that the availability of these depends on macro-economic determinants, including health and public health investment. Analysis of the relationship between health system organisation and cancer outcome is complicated and requires more information than is at present available. To describe cancer and cancer management in Europe, the European Cancer Health Indicator Project (EUROCHIP) has proposed a list of indicators that have to be adopted to evaluate the effects on outcome of proposed health system modifications.

Cause of death and long-term survival in patients with neuro-epithelial brain tumours: a population-based study

Long-term survivors of neuro-epithelial brain tumours have a higher death rate compared with the general population and the aims of this study were to investigate the causes of death and analyse long-term survival using population-based material. A total of 6209 patients were registered in the period of 1970-1993 with a primary intracranial neuro-epithelial tumour in the The Norwegian Cancer Registry. In a pilot study, a high level of agreement with regard to the cause of death was found between clinical data and the registered cause of death. Underlying causes of death in the whole population were therefore analysed. Most deaths were caused by the primary neuro-epithelial brain tumour within 10 years of diagnosis. Although the numbers were small, the proportion of patients dying from other cancers, vascular disease, infections and accidents continued to rise with time. Survival was computed using the Kaplan-Meier method. For children, survival at 5, 10 and 15 years significantly improved from the time period of 1970-1981 to 1982-1993 (47.9, 43.6 and 43.3% versus 63.8, 59.8 and 59.8%, respectively, P <0.0001). Similar improvements in survival at 5, 10 and 15 years were observed for young adults aged 15-49 years (32.7, 21.3 and 16.5% versus 50.1, 37.5 and 33.1%, for the same time periods, P<0.0001). No such improvement for those aged 50 years and over was observed (corresponding figures of 6.6, 3.8 and 2.8% versus 7.7, 4.8 and 3.4%). Prognosis for those with childhood medulloblastomas improved significantly, as did the prognosis of younger adults with low-grade gliomas and unbiopsied/ unclassifiable grade gliomas.

Trends in colorectal cancer incidence in Norway by gender and anatomic site: an age-period-cohort analysis

The purpose of this study was to examine the secular trend of colorectal cancer in Norway by gender and subsite. All new cases of cancer in proximal colon, distal colon and rectum diagnosed between 1958 and 1997 in Norway were included in the study, altogether 34 202 and 34 097 cases for men and women, respectively. The incidence data were fitted separately for each gender and subsite to an age-period-cohort model. An increase in incidence of colorectal cancer was seen from 1958 to 1997 for both men and women, although a moderate attenuation of the increase has taken place in the last 15-20 years. This observation is most pronounced for cancer of the distal colon, but is also evident for proximal colonic and rectal cancers. For the distal colon and rectum, the period effect is more important than the cohort effect for both genders, whilst opposite for the proximal colon. The main estimated trend for cohort effects is a steady increase for both men and women, apart from an unexpected drop in incidence among the cohorts born during or shortly after World War II. These findings indicate that different aetiological risk factors may act on cancers of the proximal and distal part of the large bowel and further suggest that exogenous risk factors acting very early in life may play a more important role for colorectal cancer than previously recognized.

Cancer in siblings of children with cancer in the Nordic countries: a population-based cohort study

BACKGROUND

In some rare inherited disorders such as Li-Fraumeni syndrome, relatives of children with cancer are at increased risk of cancer. We aimed to assess relations between childhood cancer and sibling risk, and evaluate the influence of recessive conditions in cancer causation.

METHODS

We did a population-based cohort study in the Nordic countries of 42277 siblings of 25605 children with cancer. Children with cancer were identified from records in the five Nordic cancer registries, and their siblings from nationwide population registries. Cancers in siblings were documented through record linkage with cancer registries and compared with national incidence rates. We also assessed cancer incidence in parents to identify familial cancer syndromes.

FINDINGS

284.2 cancers were expected in siblings, whereas 353 were diagnosed (standardised incidence ratio 1.24 95% CI 1.12-1.38). Risk ratios for siblings were highest in the first decade of life (2.59, 1.89-3.46). We excluded 56 families with genetic syndromes linked to cancer, which reduced this ratio from 1.7 to 1.0 (0.7-1.3) for siblings younger than 20 years, and from 1.3 to 1.0 (0.8-1.3) for those aged 20-29 years. We found no new patterns of familial cancer that indicated inherited susceptibility, or evidence that recessive conditions might contribute to cancers not explained by syndromes. 40% of cancers in siblings that occurred before age 20 years could be attributed to known genetic factors, whereas 60% remained unexplained.

INTERPRETATION

Apart from rare cancer syndromes, paediatric cancer is not an indicator of increased cancer risk in siblings.

Second malignant neoplasms after cancer in childhood and adolescence: a population-based case-control study in the 5 Nordic countries. The Nordic Society for Pediatric Hematology and Oncology. The Association of the Nordic Cancer Registries

Our purpose was to assess the risk of developing a second malignant neoplasm (SMN) after cancer in childhood and adolescence associated with different treatment modalities. Our investigation was performed as a nested case-control study within a Nordic cohort of 25,120 patients younger than 20 years old at first malignant neoplasm (FMN) diagnosed in 1960 through 1987. SMNs were diagnosed in 1960 through 1991. For each case of SMN, 3 controls were sampled, matched by sex, age, calendar year of diagnosis and length of follow-up. For the final analysis, there were 234 cases and 678 controls. Relative risks (RRs) of various exposures were estimated by means of conditional logistic regression, with non-exposed as the reference. The RR of developing SMN in the radiated volume was 4.3 (95% confidence interval 3.0-6.2). The risk was highest in children diagnosed before the age of 5 years; it increased with the dose of radiation and with increasing follow-up time after FMN. Chemotherapy alone was not associated with an increased RR, but it significantly potentiated the effect of radiotherapy. RRs were unchanged between the periods 1960-1973 and 1974-1987, and since the use of chemotherapy increased in the latter period, the number of SMNs may increase. Hereditary factors were important for the occurrence of SMN independently of therapy. We conclude that radiation was the most important treatment-related risk factor for the development of SMN. Chemotherapy appeared to play only an accessory role during the study period, potentiating the carcinogenic effect of radiotherapy.

[Psychological, social and economic situation of women surgically treated for cancer]

INTRODUCTION

As part of an international effort, a study of the psychosocial condition of women with cancer in Norway was performed in 1997.

MATERIAL AND METHODS

851 women with breast or gynaecological cancer in 27 Norwegian hospitals were asked to fill in a multi-choice questionnaire.

RESULTS

76% of the breast cancers were detected by the women themselves, 19% by mammography and 11% by clinical examination. Similar numbers for gynaecological cancer were 59% by the women and 41% by the doctors (13% screening smear). 25% of the women were informed about the cancer diagnosis by telephone and 9% by letter. 87% were satisfied with treatment and care, 7% dissatisfied. 62% were satisfied with the availability of doctors, 20% not. In 47% of the breast cases, therapy alternatives were discussed with the patients. In 23% of gynaecological, 50% of breast, and 72% of gynaecological cancer, patients had no wish to participate in the decision. 94 of a total of 850 patients (11%) experienced financial problems after the diagnosis had been established. More than 90% of the women had a better or unchanged relation to their partner, family and friends after treatment. However, 30% of the breast and 14% of the gynaecological cancer patients had problems with their body image, and 16% and 15% felt they were less sexually attractive. 89% felt their partner coped well with the situation, 9% had problems and only 2% lost their partner. 32% of the patients had used alternative medicine, 44% of those with recurrence and 28% under primary treatment.

INTERPRETATION

Women operated for breast and gynaecological cancer face a variety of psychosocial and financial problems.

[Diagnostic delay in malignant melanoma]

BACKGROUND

Malignant melanoma accounts for 1 to 3% of all cancers and has been the most rapidly increasing type of cancer during the last decades. Early diagnosis and treatment favours a good prognosis. We wanted to investigate delays in the diagnostic process and patients' knowledge concerning malignant melanoma.

MATERIAL AND METHODS

457 patients with primary cutaneous malignant melanoma received a questionnaire through their physician; 352 (77%) returned the questionnaire.

RESULTS

Median patient delay, defined as time between the patient's first observation of changes in a naevus and the first medical consultation, was eight weeks. Younger men had the longest patient delays. Median professional delay, defined as time from the first medical consultation to the time of diagnosis, was one week. 60% of the patients observing changes in a naevus did not initially seek medical advice, as they did not believe the changes were significant. In 65% of the cases, the patients themselves initiated the consultation. Television and other media were principal sources of information.

INTERPRETATION

Public campaigns should be designed to reach younger men in particular and focus on self-examination of naevi and immediate contact with a physician when a suspicious lesion is discovered.

Population-based surveillance by colonoscopy: effect on the incidence of colorectal cancer. Telemark Polyp Study I

BACKGROUND

Most cases of colorectal cancer (CRC) develop from adenomas. Polypectomy is believed to reduce the incidence of CRC, but this effect has never been explored in prospective controlled studies. The aim of the present study was to evaluate the effect of polypectomy on colorectal cancer incidence in a population-based screening program.

METHODS

In 1983, 400 men and women aged 50-59 years were randomly drawn from the population registry of Telemark, Norway. They were offered a flexible sigmoidoscopy and, if polyps were found, a full colonoscopy with polypectomy and follow-up colonoscopies in 1985 and 1989. A control group of 399 individuals was drawn from the same registry. In 1996 both groups (age, 63-72 years) were invited to have a colonoscopic examination. Hospital files and the files of The Norwegian Cancer Registry were searched to register any cases of CRC in the period 1983-96.

RESULTS

At screening endoscopy 324 (81%) individuals attended in 1983 and 451 (71%) in 1996. From 1983 to 1996, altogether 10 individuals in the control group and 2 in the screening group were registered to have developed CRC (relative risk, 0.2; 95% confidence interval (CI), 0.03-0.95; P = 0.02). A higher overall mortality was observed in the screening group, with 55 (14%) deaths, compared with 35 (9%) in the control group (relative risk, 1.57; 95% CI, 1.03-2.4; P = 0.03).

CONCLUSION

Endoscopic screening examination with polypectomy and follow-up was shown to reduce the incidence of CRC in a Norwegian normal population. The possible effect of screening on overall mortality should be addressed in larger studies.

Risk of cancer among offspring of childhood-cancer survivors. Association of the Nordic Cancer Registries and the Nordic Society of Paediatric Haematology and Oncology

BACKGROUND

Increasing numbers of children with cancer survive and reach reproductive age. However, the risk of cancer (other than retinoblastoma) in the offspring of survivors of childhood and adolescent cancer is uncertain.

METHODS

Using data from national cancer and birth registries, we assessed the risk of cancer among 5847 offspring of 14,652 survivors of cancer in childhood or adolescence diagnosed since the 1940s and 1950s in Denmark, Finland, Iceland, Norway, and Sweden. The offspring were followed up for a diagnosis of cancer for 86,780 person-years, and standardized incidence ratios were calculated.

RESULTS

Among the 5847 offspring, 44 malignant neoplasms were diagnosed (standardized incidence ratio, 2.6; 95 percent confidence interval, 1.9 to 3.5). There were 17 retinoblastomas, yielding a standardized incidence ratio of 37. There were 27 neoplasms other than retinoblastoma (standardized incidence ratio, 1.6; 95 percent confidence interval, 1.1 to 2.4). The second most common primary site of cancer among the offspring was the brain and nervous system, in which eight tumors were observed (standardized incidence ratio, 2.0; 95 percent confidence interval, 0.9 to 3.9.) There were between zero and four apparently sporadic cases of cancer in other primary sites among the offspring. Excluding 4 likely cases of hereditary cancer and 2 subsequent cancers among the offspring with hereditary retinoblastoma, there were 22 sporadic cancers, for a standardized incidence ratio of 1.3 (95 percent confidence interval, 0.8 to 2.0).

CONCLUSIONS

There is no evidence of a significantly increased risk of nonhereditary cancer among the offspring of survivors of cancer in childhood.

A lack of neuroblastoma in Down syndrome: a study from 11 European countries

An epidemiological investigation in 11 European countries comprising a total childhood population of 54.1 million children and using 8 separate data sources was conducted to evaluate the occurrence of neuroblastoma in Down syndrome (DS). No cases of DS were detected among 6724 infants and children with neuroblastoma, although more than five were expected. This highly significant result (P = 0.0045 according to the Poisson test) is consistent with data in the literature, which contains only two poorly detailed cases in epidemiological studies and one ganglioneuroma in a DS mosaic patient. Like other tumors, such as leukemias, testicular germ cell tumors and lymphomas are in excess in DS patients; the lack of neuroblastomas does not reflect a general decreased incidence of cancer but rather a specific underrepresentation of this precise tumor. S-100 b protein, the gene for which maps to the long arm of chromosome 21, (a) is overproduced in DS patients, (b) produces growth inhibition and differentiation of neural cells in vitro, (c) is abundant in good-prognosis neuroblastomas, and (d) has been shown to induce growth inhibition and differentiation and cell death in several human and murine neuroblastoma cell lines and could be responsible for this variation. Additional epidemiological and experimental studies are warranted to confirm our interpretation of these data.

Risk of second cancers in classical Kaposi's sarcoma

An association between Kaposi's sarcoma (KS) and malignant lymphoma has been suspected for many years. Both cancers belong to the group of malignancies associated with immune suppression and have been known to occur in the same individual. Accordingly, a common etiology has been suspected. Through linkage within the Nordic cancer registries, we studied the occurrence of cancers in a population-based cohort of 741 patients with classical KS. The relative risk of subsequent malignancies was expressed as the ratio of the observed numbers of cancer to the numbers expected based on age-, sex-, period- and country-specific incidence rates, i.e., the standardized incidence ratio (SIR). A total of 104 cancers was observed during 5,802 person-years of follow-up, which was close to the expected 98.8 cases (SIR, 1.05). During the first year of follow-up, 3 lymphomas were observed, which is in significant excess of the 0.2 lymphomas expected (SIR, 13.0). In contrast, no lymphomas occurred in the period beyond the first year of follow-up vs. 2.3 expected. Cancers of the buccal cavity and pharynx (SIR, 10.6; n = 4) and of the colon (SIR, 2.7; n = 7) occurred in excess among women but not among men. Accordingly, our results indicate that patients with classical KS are not at increased risk of cancer in general. In particular, the overall risk of lymphomas was not significantly increased. The high relative risk of malignant lymphoma immediately after KS was based on a limited number of cases, and this observation is unlikely to indicate a common etiology.

Provocative appeals in anti-smoking mass media campaigns targeting adolescents--the accumulated effect of multiple exposures

This paper reports findings from a longitudinal study that evaluated the accumulated effect of three consecutive mass media campaigns using provocative and dissonance arousing appeals to prevent cigarette smoking by adolescents. In the spring of 1992, all eligible adolescents aged 14 and 15 in one intervention county (N = 4898) and one control county (N = 5439) in Norway were included in the study, and were followed until they were 17 and 18 years of age in 1995. Only students who completed questionnaires both in 1992 and 1995 were included in the analyses. Among the non-smokers at baseline, a significantly lower proportion of adolescents of both genders had started to smoke in the intervention county compared to the proportion in the control county. Among those who were smokers at baseline, significantly more girls in the intervention county had stopped smoking than in the control county, while no significant difference between the counties was detected among boys. Our findings suggest that provocative and dissonance arousing appeals that create affective reactions and lead to interpersonal communication should be given more attention in campaigns designed to influence adolescent smoking. However, such appeals may easily produce negative reactions and the normative context should be thoroughly considered when using such appeals in future interventions.

Epidemiology of Kaposi's sarcoma in the Nordic countries before the AIDS epidemic

Based on data from the Nordic cancer registries, time-related trends in incidence of Kaposi's sarcoma (KS) were analysed in four ethnically similar populations before the AIDS epidemic. Data were available for different time periods in Denmark (1970-79), Sweden (1958-79), Finland (1953-79) and Norway (1953-79). KS was more common among men than among women aged 60 years or more, whereas no differences were observed for younger persons. The incidence of KS differed significantly between the four countries (P = 0.0001); Sweden having the highest and Denmark the lowest rates. Similarly, regional differences in incidence were observed within Sweden, rates being higher in the northern than in the southern areas (Ptrend = 0.002). Overall, in Nordic men the world standardised incidence rose from 0.5/1,000,000 person-years in the period 1953-57 to 1.8/1,000,000 person-years in 1978-79; in Nordic women, the corresponding rates were 0.2/1,000,000 person-years and 0.8/1,000,000 person-years respectively. The rate of increase was similar in Sweden, Finland and Norway (P = 0.14), whereas the short period of observation in Denmark precluded precise assessment of time-related incidence trends. These observations cannot be explained by registrational procedures or known risk factors for KS, and argue that environmental factors play an important role in the development of the disease.

Polypectomy of adenomas in the prevention of colorectal cancer: 10 years' follow-up of the Telemark Polyp Study I. A prospective, controlled population study

BACKGROUND

The efficacy of polypectomy in preventing colorectal cancer (CRC) has never been demonstrated in a controlled, prospective study. This must be done by randomization within a population with a high prevalence of colorectal polyps, and the feasibility and safety of endoscopic screening examination is a prerequisite for this type of study.

METHODS

The present study is a randomized, controlled study of the feasibility and safety of flexible sigmoidoscopic screening of a normal population sample of 799 men and women aged 50-59 years, findings at 2 and 6 years' colonoscopic follow-up, and the appearance of clinical colorectal cancer (CRC) after 10 years.

RESULTS

The attendance rate was high, and there were no complications. After 10 years 1 of 400 in the screening group had developed CRC (in the group of 76 (19%) not attending for screening examination). Four of 399 controls developed CRC.

CONCLUSIONS

Poor yield of polyps at follow-up, slow growth of in situ polyps, and no clinical CRC among screenees after 10 years provides support to infrequent or no colonoscopic follow-up after initial polypectomy in individuals with otherwise average risk of CRC.

K-ras mutations and HLA-DR expression in large bowel adenomas

A total of 72 sporadic colorectal adenomas in 56 patients were studied for the presence of point mutations in codons 12 and 13 of the K-ras gene and for HLA-DR antigen expression related to clinicopathological variables. Forty K-ras mutations in 39 adenomas were found (54%): 31 (77%) in codon 12 and nine (23%) in codon 13. There was a strong relationship between the incidence of K-ras mutations and adenoma type, degree of dysplasia and sex. The highest frequency of K-ras mutations was seen in large adenomas of the villous type with high-grade dysplasia. Fourteen out of 15 adenomas obtained from 14 women above 65 years of age carried mutations. HLA-DR positivity was found in 38% of the adenomas, large tumours and those with high-grade dysplasia having the strongest staining. Coexpression of K-ras mutations and HLA-DR was found significantly more frequently in large and highly dysplastic adenomas, although two-way analysis of variance showing size and grade of dysplasia to be the most important variable. None of the adenomas with low-grade dysplasia showed both K-ras mutation and HLA-DR positivity (P = 0.004). K-ras mutation is recognised as an early event in colorectal carcinogenesis. The mutation might give rise to peptides that may be presented on the tumour cell surface by class II molecules, and thereby induce immune responses against neoplastic cells.

Risk of subsequent malignant neoplasms among 1,641 Hodgkin's disease patients diagnosed in childhood and adolescence: a population-based cohort study in the five Nordic countries. Association of the Nordic Cancer Registries and the Nordic Society of Pediatric Hematology and Oncology

PURPOSE

To assess the risk of subsequent malignant neoplasms among Hodgkin's disease patients diagnosed before 20 years of age in the five Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden).

PATIENTS AND METHODS

There were 1,641 Hodgkin's disease patients identified through the national cancer registries since the 1940s or 1950s. The patients were monitored for 17,000 person-years until the end of 1991. Expected figures were derived from the age-specific incidence rates in each country and standardized incidence ratios (SIR) were calculated.

RESULTS

A total of 62 subsequent neoplasms were diagnosed (SIR, 7.7; 95% confidence interval [CI], 5.9 to 9.9). The overall cumulative risk of subsequent neoplasms was 1.9% at the 10-year follow-up point, 6.9% at 20 years, and 18% at 30 years. There were 26 subsequent neoplasms among males (SIR, 6.5; 95% CI, 4.3 to 9.6) and 36 among females (SIR, 8.9; 95% CI, 6.2 to 12), of which 16 were breast cancers (SIR, 17; 95% CI, 9.9 to 28). High risks were seen for thyroid cancer (SIR, 33; 95% CI, 15 to 62), for secondary leukemia (SIR, 17; 95% CI, 6.9 to 35), and for non-Hodgkin's lymphoma (SIR, 15; 95% CI, 4.9 to 35). The relative risk increased from 3.3 (95% CI, 1.2 to 7.1) for Hodgkin's disease patients diagnosed in the 1940s and 1950s to 15 (95% CI, 7.4 to 27) in the 1980s. The highest risk of secondary leukemia (SIR, 68; 95% CI, 18 to 174) was seen among those diagnosed with Hodgkin's disease in the 1980s.

CONCLUSION

Patients who survive Hodgkin's disease at a young age are at very high relative risk of subsequent malignant neoplasms throughout their lives. In particular, the high relative risk of breast cancer following Hodgkin's disease in the teenage years calls for enhanced activity for early diagnosis.

Quality of prostate cancer data in the cancer registry of Norway

Completeness of reporting and internal validity of the coding of prostate cancer in the Cancer Registry (CR) in Norway were examined. Data were matched and evaluated against diagnostic indices at eight selected hospitals in the country and against death certificates from Statistics Norway. Validity control was based on detailed re-analysis of an approximately 1% sample of the registered data during the period 1957-1986. The deficiency in reporting of prostate cancer was less than 1%. The grave deficiencies in hospital patient registers were considered to be of non-systematic nature and should, therefore, not impair the reliability of our investigation of incompleteness. The validity control revealed errors in 0.5% of the data elements, or, illustrated differently, 6% of the patient files had an error, of importance or not, in one of the data elements. One false positive registration was found among 298 controlled patient files (0.3%).

Cancer of the prostate in Norway 1957-1991--a descriptive study

The incidence and mortality of prostate cancer from 1957 to 1991 were studied in the Cancer Registry of Norway. The age-adjusted incidence rate increased from 26.3 to 46.6 per 100,000 person-years during the period, and more than 2000 cases are now registered yearly. The increase tends to be higher in the younger age groups, 50-59 years, and among the oldest, 90+ years. An increase was also found in cause-specific mortality, signifying a real increase in incidence over time. There is a slight urban dominance in incidence of prostate cancer. Autopsy findings account for less than 1.7% of the total. The histo- and cytological verification rate reached 94% in 1987-1991 and the percentage of localised cases was 68.4%. The median age at diagnosis in 1987-1991 was 75.1 years. Data on stage at time of diagnosis, histological differentiation and survival, reflect a small influence of earlier diagnosis. Model analysis revealed no particular birth cohort effect, either on incidence or on mortality.

Bladder tumours following chemotherapy and radiotherapy for ovarian cancer: a case-control study

A collaborative group of cancer registries and hospitals carried out a case-control study of tumours of the bladder in women who had previously been treated for ovarian cancer. A total of 63 cases of bladder tumours were identified, and 188 controls were selected matching for age, year of ovarian cancer diagnosis and survival time. Full details of the treatment for ovarian cancer were sought for both cases and for controls. The risk of bladder tumours was increased for patients who had been treated by radiotherapy alone (1.9; 95% confidence interval, 0.77-4.9), by chemotherapy alone (3.2; 0.97-10), and by chemotherapy and radiotherapy (5.2; 1.6-16), when comparison was made with patients treated only by surgery. Patients treated by chemotherapy were separated into 2 groups according to whether they had received cyclophosphamide. Among those who had, there was a clear increase in risk (approximately 4-fold) regardless of whether or not they had also received radiotherapy. For those who received only other drugs, risk was increased substantially among patients who had also been treated by radiation, as compared with patients treated by surgery alone, and those who had received radiotherapy only. Both melphalan and thiotepa were implicated as potential bladder carcinogens on the basis of these results. The estimated risk of bladder tumours due to cyclophosphamide was more than twice the risk following radiation to the bladder, and it appeared substantially earlier. For both agents, the risk continued to increase more than 10 years after treatment began.

Assessment of fine needle aspiration cytology and histopathology for diagnosing male breast masses

OBJECTIVE

To investigate the diagnostic accuracy of fine needle aspiration cytology (FNAC) from breast lesions in males and to determine the frequency of benign versus malignant histopathologic diagnoses in surgical biopsies from male breast lesions.

STUDY DESIGN

FNAC specimens from breast lesions taken from 241 males over 8.5 years were divided into four subgroups according to the original cytologic diagnoses. Diagnostic accuracy was verified with the Norwegian Cancer Registry. Ten years' worth of material from 809 surgical biopsies from male breast lesions was subgrouped according to the original histopathologic diagnoses.

RESULTS

Of the 809 surgical biopsies, 779 (96.3%) were benign lesions. Of the 241 fine needle aspirates, 27 (11.2%) were unsatisfactory for cytologic diagnosis. Of the remaining 214 cases, 200 benign cytologic diagnoses were confirmed at follow-up. Thus, there were no false negative cytologic diagnoses; eight malignant diagnoses were confirmed by later histopathologic examination of the surgical biopsy.

CONCLUSION

To reduce the high rate of surgical biopsies of benign male breast masses, we conclude that FNAC should be performed as a standard procedure in the clinical evaluation of male breast lesions.

Childhood non-Hodgkin's lymphoma in the five Nordic countries. A five-year population-based study from the Nordic Society of Pediatric Hematology and Oncology

PURPOSE

The comparable health-care organizations and common Cancer Registry for childhood malignancies in the five Nordic countries offered an opportunity to conduct an epidemiological study on a reasonable number of childhood non-Hodgkin's lymphoma (NHL) cases collected in a population-based manner.

MATERIAL AND METHODS

All childhood cases (0-14.9 years at diagnosis) reported during the 5-year period of 1985-1989 to the Nordic Society of Pediatric Hematology and Oncology (NOPHO) Cancer Registry for childhood malignancies were reviewed and analyzed according to age, Murphy's stage, gender, site, and survival.

RESULTS

The annual incidence of NHL is 0.7 per 100,000 children in the five Nordic countries, constituting 5% of all childhood malignancies. Age distribution was even; the male/female ratio was 3:1. Age and stage were shown by Cox regression analysis to be independent prognostic factors. Older age and lower stage affected outcome favorably. The stage and site distribution was similar to previous reports. Survival data were in accordance with those expected with modern treatment protocols.

CONCLUSIONS

The incidence and relative frequency of NHL in childhood in the five Nordic countries is in agreement with previously reported data, but the even distribution of cases throughout childhood is a new finding. Older age at onset and stage of disease affect outcome favorably, whereas male gender contrary to acute lymphoblastic leukemia was not found to affect outcome.

Head and neck cancer in Norway. A study of the quality of the Cancer Registry of Norway's data on head and neck cancer for the period 1953-1991

Data from population-based cancer registries provide information on the causes and outcome of cancer and form a basis for important decision making in connection with the prevention of cancer and the planning of health services. This makes it of the utmost importance to assess the data at all stages of collection to ensure the highest possible quality. The present study focuses on the quality of the Cancer Registry of Norway's data on head and neck cancer for the period 1953-1991. When the study was started, 16,104 cases of head and neck malignancies had been registered. All histological codes were reviewed. The pathologists' reports were reevaluated for 369 cases selected according to set criteria: 133 cases received a new histological code without being excluded from the data material: 112 cases were excluded. The distribution of histological diagnoses for each location is presented. A reevaluation of 300 cases selected at random from the corrected series indicates discrepancies between the pathologist's classification and the Registry's coding in less than 2% (1.4%) of all cases. The percentage that lacked histological verification fell from 5.7% in the first decade to 2.1% during the last 9-year period. Completeness of the Cancer Registry's data base was checked against hospital-based registries and this investigation showed that virtually all new cases are reported. We conclude that the data on head and neck cancer for the studied time period meet standards that justify their use as a basis for epidemiological as well as clinical studies.

Relationship of leukemia risk to radiation dose following cancer of the uterine corpus

BACKGROUND

Radiotherapy has been linked infrequently to secondary leukemia despite extensive exposure of the active bone marrow to ionizing radiation. Few studies include substantial numbers of elderly patients.

PURPOSE

We evaluated women with cancer of the uterine corpus, the majority of whom were treated at older ages, to gain additional information on cancer risk following partial-body radiotherapy and to examine differences in risk between external-beam therapy and brachytherapy.

METHODS

A cohort of 110,000 women with invasive cancer of the uterine corpus who survived at least 1 year following their initial cancer was assembled from nine population-based cancer registries. Cancer diagnoses occurred from 1935 through 1985, and most patients were diagnosed during the 1960s and 1970s. Radiation doses were computed to 17 sections of the active bone marrow for 218 women who developed leukemia and for 775 matched control subjects.

RESULTS

Radiotherapy did not increase the risk of chronic lymphocytic leukemia (CLL) (relative risk [RR] = 0.90; 95% confidence interval [CI] = 0.4-1.9). However, for all leukemias except CLL, a significant risk was identified (RR = 1.92; 95% CI = 1.3-2.9). Overall, the pattern of risk in relation to dose was erratic and was most consistent with a constant increased risk across the entire dose range. The risk following continuous exposures from brachytherapy at comparatively low doses and low dose rates (RR = 1.80; 95% CI = 1.1-2.8; mean dose = 1.72 Gy) was similar to that after fractionated exposures at much higher doses and higher dose rates from external-beam treatment (RR = 2.29; 95% CI = 1.4-3.7; mean dose = 9.88 Gy), indicating a large difference in the estimated risk per unit dose. Risk did not vary by age at first exposure; increased risks were apparent for irradiated patients aged 65 years or older (RR = 1.77; 95% CI = 0.9-3.5).

CONCLUSION

The leukemia risk associated with partial-body radiotherapy for uterine corpus cancer was small; about 14 excess leukemia cases were due to radiation per 10,000 women followed for 10 years. Women aged 65 years or older had a radiation risk comparable with that found in younger women. The relationship of leukemia risk to radiation dose was found to be complex due to the competing processes of cell killing, transformation, and repair. At very high doses delivered at high rates, destruction of cells likely dominates, and the risk per unit dose is low. In the low dose range, where dose was protracted and delivered at relatively low dose rates, the leukemia risk appears lower than that projected from risk estimates derived from the instantaneous whole-body exposures of atomic bomb survivors.

[Second cancer. Risk of a second malignant neoplasm in persons with cancer in childhood and adolescence]

Cancer treatments in early life have in previous studies been associated in with high risks of developing a second malignant neoplasm. This study reports on the relative and attributable risks of second malignant neoplasms among 30,880 people under the age of 20, who had been identified in the files of any of the five Nordic cancer registers, 1943-1987. Overall, 247 cases of second malignant neoplasms were observed in 238 patients, yielding a relative risk for cancer of 3.6 (95% confidence interval 3.1-4.1). The risk changed significantly from 2.6 in people first diagnosed during the 1940s and 1950s to 6.9 among cohort members included in the late 1970s and 1980s. Highest levels of the relative risk were seen during the ten years immediately after first malignant diagnosis. The incidence of second malignant neoplasms attributable to the first cancer and associated treatments, however, showed a consistent rise throughout the 45 years of follow up. It was concluded that the estimated risks for second malignant neoplasms were significantly lower than those found in most large hospital based studies but compatible with the results from a similar population based study in the United Kingdom. Extent of risk and cancer pattern were similar among the Nordic countries and are believed to be representative for a large part of the European population.

[Mass screening for cervical cancer. A one-year registration of cervical cytological tests]

In 1990 the Norwegian Ministry of Health and Social Affairs decided to start an organised screening programme for cervical cancer. All women aged 25-70 years will be offered screening every three years. During the first three years of the programme, all spontaneous screening in Norway is to be reported to a central unit located at the Cancer Registry of Norway. A pilot project has been implemented in the counties of Sør-Trøndelag and Vestfold to evaluate the organisational aspects of the screening programme. A total of 509,641 smears were recorded during the first year of recording. The majority of smears were taken from women below 50 years. Most smears (88.6%) had normal tissue morphology, while 2.9% displayed various cellular changes. Smears from younger women showed the highest rate of Human papillomavirus (HPV) changes and mild (CIN 1) and moderate (CIN 2) dysplasias, whereas the rated malignant cellular changes was highest in the older age groups. The findings support the wide age range of the target group.

Cervical mass screening in Norway--510,000 smears a year

In 1990 the Norwegian Department of Health and Social Affairs decided to start a national screening program for cervical cancer. All women aged 25 to 70 years are offered cervical screening every 3 years. The mass screening is organized and run by a central unit, comprising the Cancer Registry of Norway and the National Health Screening Service. For the first 3 years, all spontaneous cervical screening in Norway is recorded in a central, computerized register. In addition, a pilot project has been implemented in two counties to evaluate the organizational aspects of the screening program. A total of 509,641 cervical smears were recorded during the first year of registration. The test frequency was highest in the age group 20 to 29 years (28.4%), while relatively few tests were performed on women in the age group 60 to 69 years (6.6%). The majority of smears (88.6%) had normal tissue morphology, whereas 2.9% displayed different cytological abnormalities. Human papillomavirus (HPV) changes and mild (CIN 1) and moderate (CIN 2) dysplasia had the highest smear rate in women under 40 years. Malignant cellular changes had the highest rate in older age groups. The imbalance in the age distribution of smears and the confinement of cytological abnormalities to the youngest and the oldest age groups support the wide target age range of the screening program.

[Treatment of anal cancer in Trøndelag]

We have retrospectively examined the medical records and prospectively studied the survival of 43 patients (37 women and six men) treated for anal cancer in the Trøndelag region of Norway during the period 1970-89. During this period, different strategies were used, ranging from primary surgery to combined chemo-radiotherapy and sphincter saving therapy. 20 patients were treated with surgery alone, nine patients first with surgery and postoperatively with irradiation because the surgery was non-radical (histologic), and 14 patients with combined chemo- and radiotherapy. The five year cancer ani-specific survival in the whole group is 69%. The predicted five year survival in the chemo-radiotherapy group is 90% versus 61% in the group treated with surgery. Primary chemotherapy combined with radiotherapy should be the preferred treatment for carcinoma of the anal canal.

Second malignant neoplasms after cancer in childhood or adolescence. Nordic Society of Paediatric Haematology and Oncology Association of the Nordic Cancer Registries

OBJECTIVE

To assess the relative risk of developing a second malignant neoplasm in people with a diagnosis of cancer in childhood and adolescence.

DESIGN

Register based follow up study.

SETTING

Populations of Nordic countries.

SUBJECTS

30,880 people under the age of 20 with a first malignant neoplasm diagnosed during the period 1943-87.

MAIN OUTCOME MEASURES

Relative and attributable risks of second malignant neoplasms by type of first cancer, age at first diagnosis, calendar period, sex, and country. Expected figures were based on the appropriate national incidence rates for cancer.

RESULTS

247 cases of second malignant neoplasms were observed in 238 patients, yielding a relative risk for cancer of 3.6 (95% confidence interval 3.1 to 4.1). The risk changed significantly from 2.6 in people first diagnosed during the 1940s and 1950s to 6.9 among cohort members included in the late 1970s and 1980s. Increases were observed for most types of cancer. Highest levels of the relative risk were seen during the 10 years immediately after first malignant diagnosis. The incidence of second malignant neoplasms attributable to the first cancer and associated treatments, however, showed a consistent rise throughout the 45 years of follow up.

CONCLUSION

The estimated risks for a second malignant neoplasm were significantly lower than those found in most large hospital based studies but compatible with the results from a similar population based study in the United Kingdom. Extent of risk and cancer pattern were similar among the Nordic countries and are believed to be representative for a large part of the European population.

Cancer in association with polymyalgia rheumatica and temporal arteritis

In our prospective controlled study, a total of 185 patients with polymyalgia rheumatica (PMR) and temporal arteritis (TA) diagnosed during 1978-83 and their 925 matched controls were cross checked with the data files at the Cancer Registry of Norway at the end of 1987. Malignancy was registered in 27 patients (14.6%) and 131 controls (14.2%) between 1953 and the end of 1987. Malignancy was registered in 16 (24.6%) of the patients with biopsy demonstrating arteritis temporalis. The hazard rate for developing malignancy after diagnosis for the whole patient population was not significantly different from the controls. The hazard rate for developing malignancy in patients with positive biopsy, however, was 2.35 times higher than in the controls (p = 0.036) and 4.40 times higher than the rest of the patient population (p = 0.007) (Cox proportional hazards model). The general long interval between diagnosis of PMR and/or TA and registration of malignancy (mean 6.5 years) is not consistent with a paraneoplastic mechanism.

Survival after transurethral and transvesical surgery in localized cancer of the prostate, Norway 1957-1981

BACKGROUND

During the period 1957-1981, there has been a gradual change in the choice of surgical methods for patients with prostate cancer in Norway, from transvesical surgery to transurethral resections (TUR-P). Radical prostatectomy was practically nonexistent in the early years of this time period. Sixty-five percent (17,696 patients) of all patients with prostate cancer reported to the Cancer Registry had no metastases at the time of diagnosis. Of these, 5414 patients underwent TUR-P, whereas 6160 patients underwent transvesical operations as primary surgery. Interest was raised in analyzing survival after primary surgery.

METHODS AND RESULTS

Five-year relative survival rates were calculated for the groups of patients undergoing each type of surgery; the rates increased steadily for both groups during the later years of the 1957-1981 period. However, survival consistently was better for patients who had transvesical surgery. The difference in 5-year relative survival rates was 10-15%. The same pattern was seen long-term survival (more than 10 years). In addition, survival rates for patients with similar grade of tumor differentiation were better for patients undergoing transvesical surgery. A multivariate analysis of survival that related age, surgical methods, grades of tumor differentiation, and diagnostic periods showed that survival was influenced most by differentiation, followed by surgery. Age was not an important factor in this analysis.

CONCLUSION

The results underline the importance of additional research regarding the precise classification of prostatic cancer at the time of diagnosis so that clinicians can better choose the proper method of surgery.

Lung cancer following Hodgkin's disease: a case-control study

It is recognized that survivors of Hodgkin's disease are at a substantially increased risk of lung cancer. A collaborative group of population-based cancer registries and major treatment centers carried out a case-control study, in which 98 cases of lung cancer were identified in patients who had survived at least 1 year following a diagnosis of Hodgkin's disease. A total of 259 matched controls were selected from patients with Hodgkin's disease who did not develop subsequent lung cancer, and for both cases and controls detailed information was abstracted from medical records concerning stage and treatment of Hodgkin's disease. Patients treated with chemotherapy alone had about twice the risk of developing lung cancer than those treated by radiotherapy alone or both modalities. There was no increase in risk with cumulative number of cycles of chemotherapy. Among patients treated with radiotherapy alone, there was an increase in risk related to estimated radiation dose to the lung. There was also a strong association between cigarette smoking and the risk of lung cancer. The finding of a higher risk following chemotherapy than following radiotherapy was unexpected, but could not be explained by any identified methodological flaws. A plausible inference from the study is that all forms of Hodgkin's disease therapy are carcinogenic to the lung and that, in particular, chemotherapy is associated with an increase in risk which is at least comparable to and perhaps higher than the risk produced by radiotherapy.

Circulating secretory component in relation to early diagnosis and treatment of liver metastasis from colorectal carcinomas

AIMS

To evaluate serum secretory component in relation to early detection and clinical management of liver metastasis in patients with colorectal cancer.

METHODS

Secretory component and carcinoembryonic antigen (CEA) were analysed in serial serum samples from 23 patients who had liver metastases as the only apparent recurrence, and in sera from 54 matched controls. Results of surgical treatment of recurrences were classified peroperatively as radical when no residual tumour was apparent and resection margins were free of disease.

RESULTS

In total, 18 (78%) patients had increased secretory component during the whole follow up period (median 16 months); 12 (52%) had raised secretory component concentrations before clinical recurrence (median lead time 5.2 months). There was no difference before recurrence between circulating secretory component and CEA in sensitivity and lead times. Seventeen patients underwent surgery for hepatic metastasis; seven had radical hepatic resection of which only two (29%) showed increased secretory component concentrations before clinical recurrence; both had concurrent raised CEA values. By contrast, secretory component was raised in 83% of those cases considered inoperable.

CONCLUSIONS

Although serum secretory component clearly increases in most patients with liver metastases, its clinical value seems questionable because secretory component apparently indicates mainly inoperable hepatic metastases.

Incidence of cancer in Norwegian workers potentially exposed to electromagnetic fields

The risk of cancer was investigated in a cohort of 37,945 male Norwegian electrical workers for whom information on job description was collected from 1960 census data and linked to the 1970 census data. The standardized incidence ratio was calculated for all cancer sites in the overall cohort by comparison with national incidence rates for economically active men at the 1960 census. The standardized incidence ratios for cancers of the breast, pleura (mesothelioma), larynx, and bladder and for soft tissue sarcoma were elevated, while those for non-Hodgkins and Hodgkins lymphoma were lower. The standardized incidence ratio for leukemia for electrical workers with 10 or more economically active years was 1.41. The standardized incidence ratio for brain tumors in this subgroup of electrical workers was 1.14. These results from a large, national, population-based study at the Cancer Registry of Norway give support to previous findings of a possible association between electrical work and the risk of leukemia.

Trends in childhood leukaemia in the Nordic countries in relation to fallout from atmospheric nuclear weapons testing

OBJECTIVE

To obtain further information about the risks of childhood leukaemia after exposure to ionising radiation at low doses and low dose rates before or after birth or to the father's testes shortly before conception.

DESIGN

Observational study of trends in incidence of childhood leukaemia in relation to estimated radiation exposures due to fallout from atmospheric nuclear weapons testing during the 1950s and 1960s.

SETTING

Nordic countries.

SUBJECTS

Children aged under 15 years.

MAIN OUTCOME MEASURES

Incidence rates of leukaemia by age at diagnosis, sex, country, and calendar year of diagnosis or year of birth; exposure category; relation between leukaemia and exposure for children aged 0-14 and 0-4 separately.

RESULTS

During the high fallout period the average estimated dose equivalent to the fetal red bone marrow was around 140 mu Sv and the average annual testicular dose 140 mu Sv. There was little evidence of increased incidence of leukaemia among children born in these years. Doses to the red bone marrow of a child after birth were higher, and during the high exposure period children would have been subjected to an additional dose equivalent of around 1500 mu Sv, similar to doses received by children in several parts of central and eastern Europe owing to the Chernobyl accident and about 50% greater than the annual dose equivalent to the red bone marrow of a child from natural radiation. leukaemia incidence and red marrow dose was not related overall, but rates of leukaemia in the high exposure period were slightly higher than in the surrounding medium exposure period (relative risk for ages 0-14: 1.07, 95% confidence interval 1.00 to 1.14; for ages 0-4: 1.11, 1.00 to 1.24).

CONCLUSIONS

Current predicted risks of childhood leukaemia after exposure to radiation are not greatly underestimated for low dose rate exposures.

Patterns of primary care and survival in 336 consecutive unselected Norwegian patients with bladder cancer

The outcome of 336 unselected patients diagnosed as having bladder cancer in 1985 in a southern health region of Norway was studied. Two hundred and forty patients had superficial bladder cancer (Tis, Ta and T1). Seventy-four had T2-3 and 17 had T4 bladder tumours at the time of diagnosis (the T-category was unknown in five cases). In 46 of 248 evaluable cases (19%) 12 or more months had elapsed between the onset of symptoms and the histological confirmation of the diagnosis. The information received from the initial routine histology report was inadequate in 51 of 240 (21%) of the patients with superficial bladder cancer. Among the 91 patients with muscle-infiltrating tumours the primary treatment varied considerably, and only 15 patients underwent total cystectomy as the initial treatment. Only 46 in whom muscle-infiltrating tumours were diagnosed initially were referred to the regional uro-oncological unit during the course of the disease. The cancer-corrected, four-year survival was 86% and 42% for superficial and muscle infiltrating bladder cancer, respectively. The comparable figures for crude survival were 64% and 34%, respectively. The lack of optimal standard treatment of muscle-infiltrating bladder cancer warrants the introduction of clinical trials to assess both curative and palliative regimens as well as to study prognostic factors such as proliferation and immunohistochemical parameters by uro-oncological units. Scandinavian Cancer Registries should consider the optional recording of the T category on the case record forms for newly diagnosed cases of bladder cancer.

Epidemiologic evidence of cancer in aluminum reduction plant workers

This paper reviews the epidemiologic evidence of cancer risks among workers in aluminum reduction plants with emphasis on associations with specific work areas and exposures. Studies of workers manufacturing carbon products outside the aluminum industry were also reviewed since the work environment is similar to that encountered in the carbon area of aluminum plants. We obtained 22 reports from references cited in earlier reviews, through compact disc literature search 1980-1990, and from the Nordic Aluminum Industry's Secretariat for Health, Environment and Safety. Six reports were excluded because the material was included in later studies or because a critical evaluation was impossible. This left 16 publications from 11 separate studies. Work in potrooms with Söderberg electrolytic cells was associated with increased risk of bladder cancer, and the increase was correlated to duration of tar exposure. There was a suggestion of increased risk of leukemias and pancreatic cancers in potroom workers, and of kidney and brain cancers without any clear association with specific exposures or work areas. Singular results showed associations between lung cancer risk and tar exposure in Söderberg plants, and between lung cancer and work in prebake or carbon plants, but interpretation was limited by inadequate data on smoking and asbestos exposure, and by problems connected with the choice of reference populations in these studies.

A multivariate study of the prognosis of oral squamous cell carcinomas. Are blood group and hemoglobin new prognostic factors?

Because blood groups and hemoglobin concentration have been associated with the risk of the development of some cancers, this study evaluated the significance of ABO and Rhesus blood groups and hemoglobin concentration as prognostic factors in oral squamous cell carcinoma (SCC). The authors examined all registered primary SCC of buccal and maxillary alveolar mucosa in the Norwegian population between 1963 and 1972. The biopsy specimens from these patients were reevaluated and borderline cases excluded. The remaining 111 cases were included in the study, and features recorded on first admission were included in the survival analyses. ABO and Rhesus blood groups were found in 99 of these patients. Multivariate survival analysis showed that tumor size, hemoglobin concentration, stage, and Rhesus blood groups were significant prognostic factors, but sex, age, treatment, duration of symptoms, ABO blood groups, and clinical appearance of the tumors were not. The prognostic value of Rhesus blood groups and hemoglobin concentration has not been previously reported for oral SCC.

Near diploid large bowel carcinomas have better five-year survival than aneuploid ones

One hundred patients who underwent surgery for large bowel carcinoma between 1978 and 1982 were examined by flow cytometric DNA quantitation of fresh tumor specimens and divided into an aneuploid (AN) group of 63 and a near diploid (ND) one of 37. All patients were followed until death (n = 63) or until December 31, 1988. Forty-one patients (65%) with AN tumors died of cancer, as did 12 patients (32%) with ND carcinomas. Thus patients with ND tumors had a better survival rate (P = 0.04) than did those with AN ones. The difference was apparent in Dukes' Stages A, B, and C, but not in Stage D. All patients with tumors in this stage died from their carcinomas irrespective of ploidy group. Multiple regression analyses (Cox) of prognostic factors revealed that the most important prognostic variables were (in descending order) Dukes' Stage D, Dukes' Stage C, and DNA ploidy pattern. Histologic grade was not significant as an independent prognostic variable. These results indicate that the presence of a distinctly aneuploid DNA ploidy pattern in large bowel carcinoma is an important prognostic variable that worsens survival rates significantly.