Anastomotic leakage after surgery for rectal cancer: a risk factor for local recurrence, distant metastasis and reduced cancer-specific survival?

AIM

The impact of anastomic leakage (AL) on the oncological outcome after anterior resection (AR) for rectal cancer is still controversial. We explored the impact of AL regarding local recurrence (LR), distant metastasis and overall recurrence (OAR). Overall and cancer-specific survival was analysed.

METHOD

Patients undergoing AR for rectal cancer with a registered AL between 1995 and 1997 and a control group were identified in the Swedish Rectal Cancer Registry. The medical records were retrieved for additional data and validation. Differences in the oncological outcome at 5-year follow-up were analysed with multivariate methods.

RESULTS

After validation, 114 patients with AL and 136 control patients with locally radical surgery for tumours in tumour-node-metastasis stages I-III were analysed. There was no difference detected between patients with AL and control patients regarding rates of LR [8% (9 of 114) vs 9% (12 of 136); P = 0.97], distant metastasis [18% (20 of 114) vs 23% (31 of 136); P = 0.37] and OAR [19% (22 of 114) vs 28% (38 of 136); P = 0.15]. The 5-year cancer-specific survival was almost 80% in both groups. In multivariate analysis, AL was not a risk factor of LR, distant metastasis or OAR and had no impact on 5-year overall or 5-year cancer-specific survival. Irrespective of the occurrence of AL, preoperative radiotherapy (P = 0.055) and rectal washout (P = 0.046) reduced the LR rate, but did not influence survival.

CONCLUSION

Anastomotic leakage was not proved to be a risk factor of worse oncological outcome. Hence, additional adjuvant treatment or extended follow-up on the basis of the occurrence of AL after AR might not be justified.

Risk factors of rectal cancer local recurrence: population-based survey and validation of the Swedish rectal cancer registry

AIM

Despite advances in rectal cancer treatment, local recurrence (LR) remains a significant problem. To select high-risk patients for different treatment options aimed at reducing LR, it is essential to identify LR risk factors.

METHOD

Local recurrence and survival rates of 4153 patients registered 1995-1997 in the Swedish Rectal Cancer Registry were analysed. LR risk factors were analysed by multivariate methods. For LR patients the registry was validated and additional data retrieved.

RESULTS

The 5-year overall and cancer-specific survival rates were 45% and 62% respectively. LR was registered in 326 (8%) patients. After R0-resections for tumours in TNM stages I-III, LR developed in 10% of tumours at 0-5 cm, 8% at 6-10 cm and 6% at 11-15 cm above the anal verge. Preoperative radiotherapy (RT) reduced the LR rate irrespective of height [0-5 cm: OR 0.50 (0.30-0.83), 6-10 cm: OR 0.42 (0.25-0.71), and 11-15 cm: OR 0.29 (0.13-0.64)]. Patients without preoperative RT had significantly higher LR risk after rectal perforation [OR 2.50 (1.48-4.24)], and almost significantly decreased LR risk when rectal washout was performed [OR 0.65 (0.43-1.00)]. Preoperative RT prolonged time to LR but did not significantly influence the survival among LR patients. LR was an isolated tumour manifestation in 103 (39%) patients with validated LR.

CONCLUSION

Preoperative RT should be considered for rectal cancer also in the upper third of the rectum. Intraoperative perforation should be avoided, and rectal washout is indicated as valuable. Follow-up for the detection of isolated LR is important. Extended follow up should be considered for patients treated with RT.

Fifty-year follow-up of mortality among a cohort of iron-ore miners in Sweden, with specific reference to myocardial infarction mortality

OBJECTIVES

This study investigates both general mortality and mortality from myocardial infarction among men employed in iron-ore mines in Sweden.

METHODS

The mortality of employees (surface and underground workers) at the iron-ore mines in Malmberget and Kiruna, Sweden was investigated. The study cohort comprised men who had been employed for at least 1 year between 1923 and 1996. The causes of death were obtained from the national cause of death register from 1952 to 2001. Indirect standardised mortality ratios (SMR) were calculated for four main causes. Mortality specifically from myocardial infarction was also analysed.

RESULTS

4504 deaths in the cohort gave an SMR for total mortality of 1.05 (95% CI 1.02 to 1.09). Mortality was significantly higher for lung cancer (SMR 1.73, 95% CI 1.52 to 1.97). There was an increased risk of injuries and poisonings (SMR 1.34, 95% CI 1.24 to 1.46) and respiratory diseases (SMR 1.14, 95% CI 1.00 to 1.28). There were 1477 cases of myocardial infarction, resulting in an SMR of 1.12 (95% CI 1.07 to 1.18). SMR was higher (1.35, 95% CI 1.22 to 1.50) for men aged <or=60 years than for those >60 years of age (1.06, 95% CI 1.00 to 1.13).

CONCLUSIONS

Mortality from myocardial infarction was higher than expected. There was also an increased risk of death from injuries and poisonings, lung cancer and respiratory diseases, as well as higher general mortality. Our findings support the results of previous studies that there is an association between working in the mining industry and adverse health outcomes.

The Swedish rectal cancer registry

BACKGROUND

An audit of all patients with rectal cancer in Sweden was launched in 1995. This is the first report from the Swedish Rectal Cancer Registry (SRCR).

METHODS

Between 1995 and 2003, 13 434 patients treated for adenocarcinoma of the rectum were registered with the SRCR; there were approximately 1500 new patients annually.

RESULTS

Approximately half had an anterior resection, a quarter an abdominoperineal resection and 15 per cent a Hartmann's procedure. The median 30-day postoperative mortality rate was 2.4 per cent and the overall postoperative morbidity rate was 35.0 per cent. The 5-year cancer-specific survival rate was 62.3 per cent. The 5-year relative survival rate was 70.1 per cent after anterior resection, 59.8 per cent after abdominoperineal resection and 39.8 per cent after a Hartmann's procedure. The crude 5-year local recurrence rate was 9.5 per cent overall, 6.1 per cent after preoperative radiotherapy and 11.4 per cent after surgery alone. For 3868 patients who had a locally curative procedure the local recurrence rate was 7.4 per cent overall, 5.9 per cent for those who had radiotherapy and 10.2 per cent for those who did not. The local recurrence rate was 2.9 per cent (28 of 968) for stage I disease, 7.9 per cent (112 of 1418) for stage II, 13.9 per cent (188 of 1357) for stage III and 8.5 per cent (45 of 532) for stage IV.

CONCLUSION

These good population-based results are due, in part, to the nationwide prospective quality assurance registration.

Does prophylactic breast irradiation prevent antiandrogen-induced gynecomastia? Evaluation of 253 patients in the randomized Scandinavian trial SPCG-7/SFUO-3

OBJECTIVES

To examine the development of antiandrogen-induced gynecomastia and breast tenderness in the first 253 patients in a randomized Scandinavian trial (SPCG-7/SFUO-3) with a 12-month complete follow-up evaluation performed by both doctors and patients.

METHODS

In this study, the treating doctor and patient decided whether prophylactic irradiation (RT) of the breast should be given to prevent antiandrogen-induced gynecomastia. At each visit, the doctor evaluated the occurrence of gynecomastia and breast tenderness. Questions about gynecomastia and breast tenderness were also included in the study quality-of-life questionnaire (Prostate Cancer Symptom Scale).

RESULTS

Mammary RT with mostly single fraction (12 to 15 Gy) electrons was given to 174 (69%) of the 253 evaluated patients. At the 1-year follow-up visit, the doctor evaluations indicated some form of gynecomastia in 71% and 28% (P <0.001) of the nonirradiated (no-RT) and irradiated (RT) patients, respectively. The patient evaluations at 1 year showed some form of breast enlargement in 78% and 44% (P <0.001) of the no-RT and RT patients, respectively. The doctors reported some form of breast tenderness at 1 year in 75% and 43% (P <0.001) of the no-RT and RT patients, respectively. The patient evaluations of breast tenderness show an expected significant increase in the RT arm at the 3-month follow-up, which was probably due to skin reactions. At 1 year, significantly more patients who marked "very much" on the Prostate Cancer Symptom Scale were seen in the no-RT group. A weak correlation between the doctors' and patients' detection of breast problems was observed.

CONCLUSIONS

The results show that, with high significance, prophylactic RT of the breast decreases the risk of antiandrogen-induced gynecomastia and breast tenderness.

Residential radon and lung cancer among never-smokers in Sweden

In this study, we attempted to reduce existing uncertainty about the relative risk of lung cancer from residential radon exposure among never-smokers. Comprehensive measurements of domestic radon were performed for 258 never-smoking lung cancer cases and 487 never-smoking controls from five Swedish case-control studies. With additional never-smokers from a previous case-control study of lung cancer and residential radon exposure in Sweden, a total of 436 never-smoking lung cancer cases diagnosed in Sweden between 1980 and 1995 and 1,649 never-smoking controls were included. The relative risks (with 95% confidence intervals in parentheses) of lung cancer in relation to categories of time-weighted average domestic radon concentration during three decades, delimited by cutpoints at 50, 80, and 140 Bq m(-3), were 1.08 (0.8--1.5), 1.18 (0.9--1.6), and 1.44 (1.0--2.1), respectively, with average radon concentrations below 50 Bq m(-3) used as reference category and with adjustment for other risk factors. The data suggested that among never-smokers residential radon exposure may be more harmful for those exposed to environmental tobacco smoke. Overall, an excess relative risk of 10% per 100 Bq m(-3) average radon concentration was estimated, which is similar to the summary effect estimate for all subjects in the main residential radon studies to date.

[Quality registry for better treatment of rectal cancer established. Economical support is required to use the benefits of the information]

The treatment of rectal cancer has changed significantly during the last 30 years. With improved surgical technique and the introduction of preoperative radiotherapy sphincter preserving surgery is now predominant and the rate of local recurrence has been reduced substantially. However, new therapy concepts may also introduce an increased risk of complications. A register to monitor quality control in rectal cancer treatment in Sweden was established in 1995. It covers over 95 per cent of the patients with rectal cancer reported to the Swedish National Cancer Registry. Collection of data and validation are done by six regional oncology centres under supervision of surgeons appointed by the hospitals involved. The results are then collated to a nationwide quality register, enabling regions to compare themselves with other regions, and hospitals with other hospitals.

Cancers in concrete workers: results of a cohort study of 33,668 workers

OBJECTIVES

To study cancer morbidity patterns in concrete workers.

METHODS

A cohort of 33,503 concrete workers was enrolled in the study from 1971-86. The average duration of follow up was 19.4 years (582,225 person-years). The workers' cancer morbidity was compared with the morbidity of the general population.

RESULTS

A total of 3572 incident cancers were observed. Significantly increased standardised incidence ratios (SIRs) were found for all malignant neoplasms (SIR 107; 95% confidence interval (95%CI) 103 to 110), cancer of the lip (SIR 179; 95%CI 134 to 234), cancer of the stomach (SIR 139; 95%CI 122 to 158), cancer of the lung (SIR 125; 95%CI 114 to 137), and cancer of the prostate (SIR 108; 95%CI 101 to 116). Reduced risk was found for cancer of the large intestine (SIR 80; 95%CI 69 to 93) and cancer of the testis (SIR 50; 95%CI 26 to 87). Smoking was more prevalent among the concrete workers than in the general population (50% v 35%).

CONCLUSION

The study has shown a slightly increased overall risk of cancer among concrete workers. The increased risk of lung cancer could entirely be due to differences in smoking habits between concrete workers and the general population. There is a possibility that the smoking also has contributed to the increased risks of stomach cancer and lip cancer, but occupational factors may have contributed to these cancer sites.

Characteristics of pregnancy and birth and malignancy in the offspring (Sweden)

OBJECTIVES

The aim of the study was to investigate whether factors of pregnancy and birth influence the risk of malignancy in the offspring.

METHODS

Data on all deliveries (248,701 births) in two counties in Sweden 1955-90 were extracted from two birth registries. The follow-up period closed at the end of 1994 and the subjects were followed up to early middle-age at most (39 years). Incidence rates of malignancy were obtained from the Cancer Register 1958-1994. Standardized incidence ratios (SIR) and relative risks (RR) were calculated.

RESULTS

Overall, few associations were detected. A significantly increased standardized incidence ratio (SIR) of 50.00 (95% CI = 13.45-99.99) was found for the relationship between Down's syndrome and lymphatic leukaemia. Elder maternal age (> or =35 years) and lymphatic leukaemia were associated with a significantly enhanced risk (SIR = 2.00; 95% CI, 1.16-3.20). Maternal age 25-34 years, compared to younger age, was associated with a reduced risk of cervical cancer (RR = 0.47; 95% CI = 0.26-0.86).

CONCLUSIONS

Although some associations, the consistent pattern of non-association indicated a low impact of intrauterine environment or changed genetic material on the future development of malignancy in the offspring up to early middle-age.

Familial prostate cancer and possible associated malignancies: nation-wide register cohort study in Sweden

There is a familial aggregation of prostate cancer, and 5 to 10% of all prostate cancers are estimated to be inherited in an autosomal-dominant mode. A population-based cohort study was performed in order to study familial prostate cancer and associated malignancies. A nation-wide register cohort study was conducted using an unselected study population. The cohort of 5,595 sons and 5,089 daughters of Swedish men found to have prostate cancer between 1959 and 1963 was identified. All types of cancer reported between 1958 and 1992 in this cohort were identified through linkage to the Swedish Cancer Registry. The expected number of different cancers was calculated using incidence rates obtained from the Registry. A highly significant increased overall standardized incidence ratio (SIR) of 1.65 (95% CI, 1.49-1.83) was obtained for prostate cancer, with 370 observed cases compared with 224 expected prostate cancers. The SIR was 3.18 among cases 45 to 49 years old at diagnosis, with the risk gradually decreasing to a SIR of 1.45 among cases over 80 years of age. Among sons and daughters with a father whose prostate cancer was diagnosed at an early age (<70 years), an increased risk for colorectal cancer SIR 1.48 (1.10-1.95) was observed. No significant difference in cancer risk for other sites was observed among the daughters and sons of men with prostate cancer. This cohort study confirms earlier studies that a positive family history of prostate cancer is an important risk factor for developing this disease. Though increased risk was found for all ages, it was more pronounced in younger men. Since no other malignancy was significantly associated with prostate cancer, it is most likely that familial prostate cancer is "site-specific".

No difference in survival between sporadic, familial and hereditary prostate cancer

OBJECTIVE

To estimate the survival of men with familial prostate cancer and compare them with prostate cancer cases unselected for family history.

PATIENTS AND METHODS

The overall and prostate cancer-specific survival was calculated in two large (249 and 304 men, respectively) population-based cohorts of men with familial prostate cancer. The tumour grade at diagnosis was also obtained in one of the cohorts.

RESULTS

There were no significant differences in either overall or prostate cancer-specific survival between familial and sporadic cases. The spectrum of tumour grades at diagnosis in familial cases did not differ from that in a population with prostate cancer unselected for family history.

CONCLUSION

No differences in treatment between men with or without a positive family history of prostate cancer are justified, based on the result from this study.

Segregation analysis of prostate cancer in Sweden: support for dominant inheritance

Several epidemiologic studies have shown familial aggregation of prostate cancer. To assess the nature of familial clustering of prostate cancer, a complex segregation analysis was performed on a population-based sample of 2,857 nuclear families ascertained through an affected father diagnosed with prostate cancer in Sweden during 1959-1963. The segregation analysis, using a large, unselected population of prostate cancer families, revealed that the observed clustering of prostate cancer was best explained by a high risk allele inherited in a dominant mode, with a high population frequency (1.67%) and a moderate lifetime penetrance (63%). This study confirms the result from one earlier published segregation analysis and provides the context for interpreting the recently published linkage of hereditary prostate cancer families to chromosome 1q 24-25 (HPC1).

Neoadjuvant chemotherapy with cisplatin and 5-fluorouracil in advanced squamous cell carcinoma of the head and neck: a randomized phase III study

BACKGROUND AND PURPOSE

In 1986 a prospective, randomized, multi-centre trial for evaluation of neoadjuvant chemotherapy with cisplatin and 5-fluorouracil in the treatment of advanced squamous cell carcinoma of the head and neck was initiated. As survival in this group of patients is poor the purpose was to find a possible survival benefit of the chemotherapy in addition to radiotherapy compared to radiotherapy only.

METHODS

Four-hundred sixty-one patients from Denmark, Norway and Sweden with tumors in oral cavity, oropharynx, hypopharynx and larynx were randomized to receive either standard treatment (radiotherapy or radiotherapy followed by surgery) or neoadjuvant chemotherapy followed by standard treatment. Chemotherapy included three courses of cisplatin 100 mg/m2 i.v. infusion on day 1 followed by 5-fluorouracil 1000 mg/m2 per day continuous i.v. infusion for 120 hours. Radiotherapy 64-70 Gy in 2 Gy per fraction, 5 times/week, was given to patients in both treatment arms.

RESULTS

Response rate was 71% for patients randomized to chemotherapy-radiotherapy and 66% for patients randomized to standard treatment (not statistically significant). Residual tumors were excised if possible. After surgery 62% of the patients randomized to chemotherapy-radiotherapy and 60% of the patients in the standard treatment group were clinically tumor free.

CONCLUSIONS

No statistically significant benefit in survival was observed for patients treated with neoadjuvant chemotherapy followed by radiotherapy. Nor was there any impact of chemotherapy on the number of patients achieving loco-regional tumor control after primary treatment.

Prostate cancer mortality in northern Sweden, with special reference to tumor grade and patient age

OBJECTIVES

This study is designed to estimate the prostate cancer-specific mortality according to patient age and tumor grade in an unselected population of patients with prostate cancer who mostly received deferred or direct hormonal treatment as initial treatment.

METHODS

The study population was composed of 6514 patients diagnosed with prostate cancer during 1971 to 1987 in northern Sweden. For those who died during follow-up, the cause of death was determined from the comprehensive Swedish registry data (population registries and causes of death registry).

RESULTS

About 85% of these patients died during the 7 to 23 years of follow-up, and the prostate cancer-specific mortality was estimated to be 55%. Age at diagnosis was found to be a strong predictor of prostate cancer death. Patients diagnosed before the age of 60 had an 80% risk of dying of prostate cancer, whereas those over 80 years of age at diagnosis had less than a 50% risk of prostate cancer-related death.

CONCLUSIONS

The prostate cancer mortality is high but decreases with older age at diagnosis. We found, using data from the causes of death registry, that the relative survival and the cause-specific survival of these patients were compatible with each other.

Residential radon and lung cancer in Sweden: risk analysis accounting for random error in the exposure assessment

A large epidemiologic study on residential radon exposure and lung cancer has been conducted in Sweden. An attempt is now made to quantify the impact of random error in the exposure assessment on the risk estimate for lung cancer in this study. The study included 1,360 lung cancer cases, diagnosed from 1980 to 1984, and 2,847 population controls. Radon measurements were performed in 8,992 dwellings occupied by the study subjects some time since 1947. Questionnaires provided information on smoking and other risk factors. Imprecision in the retrospective exposure assessment for radon was estimated from a Monte Carlo technique modeling Swedish conditions. Adjusted risk estimates were obtained from regression analyses based on expected values for true time-weighted average residential radon concentration (TWA), conditional on observed TWA. Without adjustment for random error in the TWA estimates, the linear excess relative risk coefficient was 0.10 per 100 Bq m(-3), but an excess relative risk of about 0.15 to 0.20 per 100 Bq m(-3) was suggested following adjustment. The potentially significant consequences of errors in the retrospective radon exposure assessment should be taken into consideration in the risk estimation as well as in comparisons of results of different studies and in future pooled analyses.

Total food consumption and body mass index in relation to prostate cancer risk: a case-control study in Sweden with prospectively collected exposure data

PURPOSE

Prostate cancer is the most common cancer among men and accounts for most cancer related deaths in Sweden today. To find or confirm exogenous risk factors for prostate cancer a population based case-control study was performed.

MATERIALS AND METHODS

By linking the Swedish Cancer Registry with the Swedish Twin Registry 406 cases of prostate cancer were selected from the twin register. As controls 1,218 men without prostate cancer were randomly selected from the same register. The selection procedure ensured that no cases or controls were related to each other. Questionnaire concerning height, weight, dietary habits, and alcohol and tobacco consumption were mailed in 1967 and 1970 to members in the twin register and the collected information was used in this study.

RESULTS

There was a positive trend for prostate cancer risk seen for total food consumption to (p < 0.001) with an odds ratio of 2.22 (95% confidence interval 1.23 to 3.99) for those who consumed somewhat more and 3.89 (1.09 to 13.96) for those who consumed much more than people in general. An increased trend was also seen for body mass index (BMI) (p = 0.015), with an odds ratio of 1.44 (0.98 to 2.11) for 26 to 29 kg./m.2 and 1.80 (1.07 to 3.04) for BMI greater than 29 kg./m.2 compared with BMI less than 23 kg./m.2. Total food consumption and BMI remained independent risk factors in a multivariate analysis. All specific food items studied, as well as tobacco and alcohol consumption, were unrelated to prostate cancer risk.

CONCLUSIONS

This study suggests that high BMI and total food consumption are independent risk factors for prostate cancer and that dietary habits are important in the development of this tumor. It is also unlikely that neither tobacco nor alcohol use substantially changes the risk of prostate cancer.

Familial prostate cancer in Sweden. A nationwide register cohort study

BACKGROUND

Although prostate carcinoma is not widely recognized as a familial cancer, familial aggregation of this disease has been shown in some retrospective case-control studies. To study familial prostate cancer in Sweden, a population-based cohort study was performed, that attempted to avoid possible bias connected with some earlier studies of familial prostate cancer.

METHODS

A nationwide register cohort study was conducted using an unselected study population. The study cohort of 5496 sons of Swedish men found to have prostate cancer between 1959 and 1963 was identified through parish offices. All prostate cancer patients reported between 1958 and 1990 in this cohort were identified through linkage to the Swedish Cancer Register. The expected number of prostate cancer patients was calculated using incidence rates obtained from the same register.

RESULTS

A highly significant increased overall standardized incidence ratio (SIR) of 1.70 (95% confidence interval, 1.51-1.90) was obtained for prostate cancer in this cohort, with 302 observed cases compared with 178 expected prostate cancers. The SIR was 3.38 among patients aged 45-49 years at diagnosis, with the risk gradually decreasing to a SIR of 1.35 among patients older than 80 years (trend, P = 0.013). Among sons with a father whose prostate cancer was diagnosed at an early age (< 70 years), a significant trend (P = 0.01) for prostate cancer risk was observed due to early onset of the disease.

CONCLUSIONS

This cohort study provides further evidence that a positive family history of prostate cancer is a risk factor for developing the disease in an unselected population. The increased risk was found for all ages, but was more pronounced in younger men.

A cohort study with regard to the risk of haematological malignancies in patients treated with x-rays for benign lesions in the locomotor system. I. Epidemiological analyses

Roentgen treatment for painful benign conditions in the locomotor system as arthrosis and spondylosis was in Sweden very common up to the beginning of the 1960s. The mode of treatment differed from the British ankylosing spondylitis series as smaller parts of the red bone marrow were exposed and smaller doses were applied. A cohort of 20,024 such patients treated 1950-1964 at two hospitals in northern Sweden was analysed with regard to the risk of haematological malignancies. Average factors for conversion of prescribed skin doses to mean absorbed red bone marrow doses were estimated on random samples of the different treatment sites and then applied on the cohort in its whole. The standard incidence ratio (SIR) for leukaemia was 1.18 (95% CI: 0.98-1.42) and the standard mortality ratio (SMR) 1.25 (0.99-1.45). In the highest dose group (mean absorbed red bone marrow dose > 0.5 Gy) the corresponding values were 1.40 (1.00-1.92) and 1.50 (1.08-2.04). In the mortality analysis also a slightly increased myeloma risk was noted with SMR = 1.20 (0.99-1.56). Extension of the cohort and nested case-control studies are under progress.

A cohort study with regard to the risk of haematological malignancies in patients treated with x-rays for benign lesions in the locomotor system. II. Estimation of absorbed dose in the red bone marrow

A cohort study with regard to the risk of haematological malignancies was performed on about 20,000 patients who in 1950-1964 received roentgen treatment for benign conditions in the locomotor system. In order to estimate the mean absorbed red bone marrow dose the treatments were classified as concerning 10 sites (cervical spine, thoracic spine, lumbar spine, sacral region, shoulder, hip, elbow, wrist, knee and ankle). The four last-mentioned sites do not normally contain red bone marrow in adults and their contribution to the mean absorbed dose was regarded as zero. For the other 6 sites random samples consisting of 30 patients for each site were drawn from the cohort. By use of the treatment records and data from the literature on some physical parameters and red bone marrow distribution in normal adult persons, average conversion factors were calculated by which the subscribed surface dose could be converted into mean absorbed dose in red bone marrow. These conversion factors were then applied on the whole cohort and used for stratification of it according to different levels of exposure.

Studies of genetic factors in prostate cancer in a twin population

It has been suggested that positive family history constitutes a risk factor for the development of prostate cancer. Familial clustering of prostate cancer might suggest that genetic factors are of importance in the etiology of this disease. To elucidate further the relative importance of genetic factors, we studied prostate cancer among an unselected Swedish twin population. Information from the Swedish Twin Registry and the Swedish Cancer Registry was used. In 4,840 male twin pairs 458 prostate cancers were identified between 1959 and 1989. Among these 16 monozygotic and 6 dizygotic twin pairs were concordant for prostate cancer. Proband concordance rates of 0.192 and 0.043, and a correlation of liability of 0.40 and -0.05 were found for monozygotic and dizygotic pairs, respectively. These differences in proband concordance rates and correlations of liability for monozygotic pairs compared to dizygotic pairs are pronounced. The results indicate that genetic factors might be of importance for the development of prostate cancer. The results of this study indicate the need for further investigations of genetic factors in prostate cancer, including large scale epidemiological studies and investigations of molecular genetics of risk families.

Residential radon exposure and lung cancer in Sweden

BACKGROUND

Residential radon is the principal source of exposure to ionizing radiation in most countries. To determine the implications for the risk of lung cancer, we performed a nationwide case-control study in Sweden.

METHODS

The study included 586 women and 774 men 35 to 74 years of age with lung cancer that was diagnosed between 1980 and 1984. For comparison, 1380 female and 1467 male controls were studied. Radon was measured in 8992 dwellings occupied by the study subjects at some time since 1947. Information on smoking habits and other risk factors for lung cancer was obtained from questionnaires.

RESULTS

Radon levels followed a log-normal distribution, with geometric and arithmetic means of 1.6 and 2.9 pCi per liter (60.5 and 106.5 Bq per cubic meter), respectively. The risk of lung cancer increased in relation to both estimated cumulative and time-weighted exposure to radon. In comparison with time-weighted average radon concentrations up to 1.4 pCi per liter (50 Bq per cubic meter), the relative risk was 1.3 (95 percent confidence interval, 1.1 to 1.6) for average radon concentrations of 3.8 to 10.8 pCi per liter (140 to 400 Bq per cubic meter), and it was 1.8 (95 percent confidence interval, 1.1 to 2.9) at concentrations exceeding 10.8 pCi per liter. The estimates of risk were in the same range as those projected from data in miners. The interaction between radon exposure and smoking with regard to lung cancer exceeded additivity and was closer to a multiplicative effect.

CONCLUSIONS

Residential exposure to radon is an important cause of lung cancer in the general population. The risks appear consistent with earlier estimates based on data in miners.

Histological types of lung cancer among smelter workers exposed to arsenic

The histological distribution of lung cancer was investigated in 93 men who had worked at a Swedish smelter with high levels of arsenic. A comparison was made with a group of 136 patients with lung cancer from the county where the smelter was located. Company records provided information on occupational exposure and data on smoking habits were obtained from a next of kin of each subject. No pronounced differences in the histological types of lung carcinomas between smelter workers and the reference group could be seen for smokers. Some analyses indicated an increased proportion of adenocarcinomas among the smelter workers, which confirmed earlier data, but these findings were difficult to interpret. Cases among smelter workers who had never smoked showed a histological distribution resembling that in smokers, indicating that the work environment at the smelter and smoking had a similar influence on the risk for different types of lung cancer.

Tumor markers in mammary carcinoma. An evaluation of carcinoembryonic antigen, placental alkaline phosphatase, pseudouridine and CA-50

In 104 patients with breast cancer, carcinoembryonic antigen (CEA), placental alkaline phosphatase (PLAP) and the carbohydrate antigen CA-50 were analysed in serum. Excretion of the modified nucleoside, pseudouridine, was analysed in urine. The patients were subdivided in three different clinical stages according to disease manifestations. Levels of CEA and pseudouridine correlated to clinical stage and 58 per cent of the patients with distant metastases had elevated levels of CEA, compared with 36 per cent for pseudouridine. For PLAP and CA-50, the levels did not show any clear correlation to clinical stage. Increased activity of PLAP correlated strongly to tobacco smoking. A decrease in the level of CEA was observed following radical mastectomy. Increase in CEA levels predicted relapse in 5 out of 14 patients within about 3 to 6 months. In patients with tumor manifestations, elevated CEA levels predicted an inferior prognosis compared to those with ordinary levels.

Underground mining, smoking, and lung cancer: a case-control study in the iron ore municipalities in northern Sweden

A case-control study of lung cancer in males was performed in two municipalities in northern Sweden with large iron ore mines. Previous studies had revealed an increased lung cancer risk for underground workers in these mines, with all probability related to radon daughter exposure. Data concerning underground mining and smoking were obtained from questionnaires. All analyses suggested an interaction of a multiplicative type between underground mining and smoking in the causation of lung cancer in this population. The calculated population etiologic fraction was about 45% for underground mining and about 80% for smoking.

Professional driving, smoking, and lung cancer: a case referent study

In a case referent study of about 600 cases of male lung cancer in northern Sweden the risk in professional drivers was specifically studied. Data concerning occupations, time and type of employment, and smoking habits were collected by questionnaires directed to close relatives. On average, professional drivers were heavier smokers and this was the chief cause of a slightly increased crude risk ratio in the study as a whole. Smoking drivers in an upper age group (70 and over) had a high relative risk of lung cancer, whereas in a lower age group (under 70) no significant increase was found. The relative risk in non-smoking drivers in the upper age group was moderately raised with borderline statistical significance. The high relative risk estimated for smoking drivers in the upper age group suggests a synergistic effect between smoking and occupational exposure.

Tumor markers in colorectal carcinoma. An evaluation of carcinoembryonic antigen, tissue polypeptide antigen, placental alkaline phosphatase and pseudouridine

The biologic markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), placental alkaline phosphatase ( PLAP ) and pseudouridine were analysed in 37 patients with colorectal carcinoma. CEA, TPA and PLAP were derived from the serum and pseudouridine from the urine. The incidence of all four markers increased with advancing stages of the disease. Patients with distant metastases had elevated levels of CEA, TPA, PLAP and pseudouridine in 85, 27, 18 and 33 per cent of the total cases, respectively. When survival was compared, patients with 2 to 4 elevated markers had shorter survival than those with none or only one elevated marker.

Occurrence of other malignancies in patients treated for basal cell carcinoma of the skin. A cohort study

The patient with basal cell carcinoma of the skin has sometimes been thought to run an increased risk for developing other malignancies. A retrospective cohort study of 468 cases including about 4 400 person-years of observation did not reveal a significant deviation from expected values estimated either from cancer register data or from cancer incidence in matched controls.

Tumor markers in bronchogenic carcinoma. An evaluation of carcinoembryonic antigen, tissue polypeptide antigen, placental alkaline phosphatase and pseudouridine

From 62 patients with bronchogenic carcinoma, carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), placental alkaline phosphatase (PLAP) in serum and pseudouridine, a modified nucleoside, were analysed in urine. About 60 per cent of the patients had squamous cell carcinoma, and 20 per cent had small cell carcinoma. The patients were allocated into 3 different clinical stages based upon tumor burden, and the markers were analysed before treatment and thereafter. TPA and PLAP had limited value as biologic markers. For both CEA and pseudouridine the frequency of elevated values increased parallel to clinical stage. Elevated levels of these 2 markers were also correlated to shorter survival.

Evaluation of carcinoembryonic antigen, tissue polypeptide antigen, placental alkaline phosphatase, and modified nucleosides as biological markers in malignant lymphomas

We have evaluated CEA, TPA, PLAP in sera from patients with three different kinds of malignant lymphomas. Six modified nucleosides, psi, m1A, m1G, m1I, m2G, and m2(2)G were analyzed in the urine from the same group of patients. The histological diagnoses were histiocytic lymphoma (21 patients), lymphocytic lymphoma (19 patients) and Hodgkin's disease (23 patients). The patients were classified into four different clinical stages. Consecutive samples were analyzed before and during ongoing radiotherapy and chemotherapy and during the post-treatment period. Our results showed that TPA and PLAP had limited value as biological markers for patients with malignant lymphomas. For CEA a possible correlation with clinical stage was observed only in patients with Hodgkin's disease. The modified nucleosides, especially psi, showed a correlation with clinical stage for patients with all three diagnoses. Elevated levels of psi in urine were in healthy adults 4%, in patients in clinical stage 1 14%, and in patients with advanced disease 62%. Six cases showed a good correlation between the change in clinical stage upon treatment and the parallel change in the level of psi in the urine. Our results suggest that modified nucleosides, especially psi, are valuable as biological markers for patients with malignant lymphomas.

The impact of growth pattern on survival in non-Hodgkin's lymphomas classified according to Lukes and Collins

203 cases of non-Hodgkin's lymphomas assigned as follicle centre cell (FCC) type according to the classification of Lukes and Collins (1975) were analyzed according to growth pattern. Nodular cases had a better prognosis than diffuse ones even within a certain cell type. The abundance of parafollicular lymphocytes was a better criterium of nodularity than prominence of venules. Degrees of nodularity was best scored according to distribution of diffuse and nodular areas. Prognosis was better with a higher degree of nodular growth even within a certain cytological cell type. Therefore it is proposed that scoring according to different degrees of nodularity has a high prognostic impact and could be an alternative to scoring according to cell type within the group of follicle centre cell lymphomas.

Combined effects of mining and smoking in the causation of lung carcinoma. A case-control study in northern Sweden

Within a case-control study of male lung carcinoma in northern Sweden combined effects of underground mining (iron ore mines) and smoking were analysed. A synergistic effect was found approximately of multiplicative type. Cases with lung carcinoma exposed to underground mining had a considerably lower average cumulative tobacco consumption than other lung carcinoma cases as an expression of the fact that smoking is particularly dangerous in underground miners. Small cell undifferentiated carcinoma was overrepresented among the cases exposed to underground mining and were especially often low tobacco consumers. In the 2 municipalities where the iron mines were located 74 per cent of the male lung carcinoma incidence could be explained by smoking and 55 per cent by underground mining (etiologic fractions).

Clinico-pathologic correlation in non-Hodgkin's lymphoma. IV. Analysis of patients with clinically localized disease

A retrospective analysis of 140 patients with non-Hodgkin's lymphoma in clinical stage I or II classified according to a modified LUKES & COLLINS scheme was performed. Three major groups were found according to cell type, with different clinical features: (1) Small cell lymphomas with a relatively favourable survival in spite of high relapse rates. (2) Large cell lymphomas with lower relapse rates, but short time between relapse and death, and unfavourable survival. (3) Mixed small/large cleaved follicular centre cell lymphoma which was most favourable with respect to relapse and survival. Nodular lymphoma had the same overall relapse rate as diffuse lymphoma, but had a significantly longer survival. Tumours stage I were associated with significantly longer relapse-free survival and survival than stage II. The importance of separating the majority of non-Hodgkin's lymphomas into three main groups according to cell type is emphasized. These major groups require different clinical approaches in terms of staging and treatment.

Clinico-pathologic correlation in non-Hodgkin's lymphoma. II. Clinical and prognostic significance of nodularity

A retrospective review of 302 patients with non-Hodgkin's lymphoma is reported. The tumors were classified according to a modified Lukes & Collins scheme and their growth pattern was analysed. Nodular growth was scored in 3 degrees. Nodularity was found to be correlated with certain clinical features and of great relevance for prognosis. The growth pattern was also correlated with cell type, but even within a certain cytologic type, nodular tumors were associated with better survival than diffuse tumors.

Clinico-pathologic correlation in non-Hodgkin's lymphoma. III. Biologic significance of a modified Lukes and Collins classification

With a modified Lukes & Collins classification of non-Hodgkin's lymphomas applied retrospectively to a patient series the biologic and clinical implications of some microscopic features were analysed. It was found that, based on this classification, proliferation, dissemination and differentiation could be explained in a comprehensible way.

Clinico-pathologic correlation in non-Hodgkin's lymphoma. I. Retrospective analysis using the Lukes and Collins classification

A retrospective review of 302 patients with non-Hodgkin's lymphoma is presented. The tumors were classified according to a modified Lukes and Collins scheme. Clinico-pathologic correlation was analysed for the subtypes. Certain distinct features were found with respect to age, sex, clinical stage and sites of involvement at admission. Prognostically, two major groups were found with significantly differing survival curves. The pathologic and clinical significance of the modified Lukes and Collins classification is discussed.