Survival of European patients diagnosed with myeloid malignancies: a HAEMACARE study.

Population-based information on the survival of patients with myeloid malignancies is rare mainly because some entities were not recognized as malignant until the publication of the third revision of the International Classification of Diseases for Oncology and World Health Organization classification in 2000. In this study we report the survival of patients with myeloid malignancies, classified by updated criteria, in Europe. We analyzed 58,800 cases incident between 1995 to 2002 in 48 population-based cancer registries from 20 European countries, classified into HAEMACARE myeloid malignancy groupings. The period approach was used to estimate 5-year relative survival in 2000-2002. The relative overall survival rate was 37%, but varied significantly between the major groups: being 17% for acute myeloid leukemia, 20% for myelodysplastic/myeloproliferative neoplasms, 31% for myelodysplastic syndromes and 63% for myeloproliferative neoplasms. Survival of patients with individual disease entities ranged from 90% for those with essential thrombocythemia to 4% for those with acute myeloid leukemia with multilineage dysplasia. Regional European variations in survival were conspicuous for myeloproliferative neoplasms, with survival rates being lowest in Eastern Europe. This is the first paper to present large-scale, European survival data for patients with myeloid malignancies using prognosis-based groupings of entities defined by the third revision of the International Classification of Diseases for Oncology/World Health Organization classifications. Poor survival in some parts of Europe, particularly for treatable diseases such as chronic myeloid leukemia, is of concern for hematologists and public health authorities.

Late and very late mortality in 5-year survivors of childhood cancer: changing pattern over four decades--experience from the Nordic countries.

Long-term survivors of childhood cancer suffer from a higher mortality than the general population. Here we evaluate late and very late mortality, and patterns of causes of death, in 5-year survivors after childhood and adolescent cancer in cases diagnosed during four decades in the five Nordic countries. The study is population-based and uses data of the nationwide cancer registries and the cause of death registers. There were in all 37,515 incident cases, diagnosed with cancer before the age of 20 years, between 1960 and 1999. The 5-year survivor cohort used in the mortality analyses consisted of 21,984 patients who were followed up for vital status until December 31, 2005 (Norway, Sweden) or 2006 (Denmark, Finland, Iceland). At the latest follow-up, 2,324 patients were dead. The overall standardized mortality ratio was 8.3 and the absolute excess risk was 6.2 per 1,000 person-years. The pattern of causes of death varied markedly between different groups of primary cancer diagnosis, and was highly dependent on time passed since diagnosis. With shorter follow-up the mortality was mainly due to primary cancer, while with longer follow-up, mortality due to second cancer and noncancer causes became more prominent. Mortality between 5 and 10 years after diagnosis continued to decrease in patients treated during the most recent period of time, 1990-1999, compared to previous periods, while mortality after 10 years changed very little with time period. We conclude that improvement of definite survival demands not only reducing early but also late and very late mortality.

Mobile phone use and incidence of glioma in the Nordic countries 1979-2008: consistency check.

BACKGROUND: Some case-control studies have reported increased risks of glioma associated with mobile phone use. If true, this would ultimately affect the time trends for incidence rates (IRs). Correspondingly, lack of change in IRs would exclude certain magnitudes of risk. We investigated glioma IR trends in the Nordic countries, and compared the observed with expected incidence rates under various risk scenarios. METHODS: We analyzed annual age-standardized incidence rates in men and women aged 20 to 79 years during 1979-2008 using joinpoint regression (35,250 glioma cases). Probabilities of detecting various levels of relative risk were computed using simulations. RESULTS: For the period 1979 through 2008, the annual percent change in incidence rates was 0.4% (95% confidence interval = 0.1% to 0.6%) among men and 0.3% (0.1% to 0.5%) among women. Incidence rates have decreased in young men (20-39 years) since 1987, remained stable in middle-aged men (40-59 years) throughout the 30-year study period, and increased slightly in older men (60-79 years). In simulations, assumed relative risks for all users of 2.0 for an induction time of up to 15 years, 1.5 for up to 10 years, and 1.2 for up to 5 years were incompatible with observed incidence time trends. For heavy users of mobile phones, risks of 2.0 for up to 5 years' induction were also incompatible. CONCLUSION: No clear trend change in glioma incidence rates was observed. Several of the risk increases seen in case-control studies appear to be incompatible with the observed lack of incidence rate increase in middle-aged men. This suggests longer induction periods than currently investigated, lower risks than reported from some case-control studies, or the absence of any association.

Increased relative risk of lung cancer in 2,904 patients with saccular intracranial aneurysm disease in eastern Finland.

BACKGROUND AND OBJECTIVE: To analyze the long-term incidence of cancer after the first diagnosis of saccular intracranial aneurysm (sIA) disease. METHODS: The Neurosurgery Department of the Kuopio University Hospital (KUH) solely serves a defined Eastern Finnish population. The Kuopio sIA database contains 2,904 consecutive sIA cases from 1980 to 2007, 618 unruptured (170 familial and 448 sporadic) and 2,286 ruptured aneurysmal subarachnoid hemorrhage (aSAH) cases (308 familial and 1,978 sporadic). They were followed for the incidence of cancer (Finnish Cancer Registry) until death (n = 1,176) or until December 31, 2008, giving a total of 26,844 person-years. Their standardized incidence ratios (SIRs) of different cancers were calculated as compared to the corresponding KUH population (year of follow-up, gender, age). RESULTS: Lung cancer after the first sIA diagnosis occurred in 30 of the 1,340 male patients [SIR = 2.0; 95% confidence interval (CI) = 1.4-2.9], and in 10 of the 1,564 female patients (SIR = 2.6; 95% CI = 1.2-4.7). Poisson regression analysis identified male gender and increasing diameter of the ruptured sIA as independent risk factors for lung cancer, while familial sIA disease, age at aSAH, site of ruptured sIA, or the presence of associated unruptured sIAs had no significant effect. CONCLUSIONS: Carriers of the sIA disease have an increased risk of developing lung cancer. Their long-term smoking habits after the sIA diagnosis should be elucidated for preventive purposes.

[The health of children born after cancer treatments]. / Syöpähoitojen jälkeen syntyneiden lasten terveys.

With the development of cancer treatments an increasing number of patients having contracted cancer at a young age will survive. Those who have recovered from cancer will, however, have children almost twice more infrequently than their siblings. Women who have received radiotherapy especially in the abdominal and pelvic region possess an increased risk of premature delivery. Progeny of the patients have been shown not to possess an increased risk of intrauterine death, death during the neonatal period or embryonic deaths. According to current knowledge, cancer treatments do not have transgenerational effects and do not increase the risk of cancer among the progeny.

Association of Merkel cell polyomavirus infection with tumor p53, KIT, stem cell factor, PDGFR-alpha and survival in Merkel cell carcinoma.

Most Merkel cell carcinomas (MCCs) contain Merkel cell polyomavirus (MCPyV) DNA, and the virus likely has a pivotal role in tumor pathogenesis. p53 and the KIT receptor tyrosine kinase have also been implicated in MCC pathogenesis, but little is known about their association with MCPyV infection. We identified 207 patients diagnosed with MCC in Finland in 1979-2004 and reviewed the histological diagnoses. Adequate clinical information, tumor tissue and DNA were available from 87 confirmed MCC cases. Presence of MCPyV DNA was assessed using quantitative PCR; p53, KIT, phospho-KIT, stem cell factor (SCF) and PDGFRα expression using immunohistochemistry and presence of mutations in KIT exons 9, 11, 13 and 17 and PDGFRA exons 10, 12, 14 and 18 using DNA sequencing. Most (77.0%) of the 87 tumors contained MCPyV DNA and 37 (42.5%) expressed KIT, whereas PDGFRα, p53, SCF and pKIT expression was less common (31.9, 22.8, 8.6 and 4.8%, respectively). No KIT or PFGFRA mutations were detected, but 10 (12.5%) of the 80 tumors studied harbored common PDGFRA exon 10 S478P substitution. Tumor p53 and KIT expression were associated with absence of MCPyV DNA (p = 0.01 and 0.009, respectively). Tumor p53 expression was associated with unfavorable MCC-specific survival (p = 0.021) and overall survival (p = 0.046), but tumor KIT expression only when stratified by presence of MCPyV DNA. The results suggest that p53 and KIT expression are associated with absence of MCPyV DNA in MCC, and that the molecular pathogenesis of MCC is multifactorial.

Survival of European patients diagnosed with lymphoid neoplasms in 2000-2002: results of the HAEMACARE project.

BACKGROUND: The European Cancer Registry-based project on hematologic malignancies (HAEMACARE), set up to improve the availability and standardization of data on hematologic malignancies in Europe, used the European Cancer Registry-based project on survival and care of cancer patients (EUROCARE-4) database to produce a new grouping of hematologic neoplasms (defined by the International Classification of Diseases for Oncology, Third Edition and the 2001/2008 World Health Organization classifications) for epidemiological and public health purposes. We analyzed survival for lymphoid neoplasms in Europe by disease group, comparing survival between different European regions by age and sex. DESIGN AND METHODS: Incident neoplasms recorded between 1995 to 2002 in 48 population-based cancer registries in 20 countries participating in EUROCARE-4 were analyzed. The period approach was used to estimate 5-year relative survival rates for patients diagnosed in 2000-2002, who did not have 5 years of follow up. RESULTS: The 5-year relative survival rate was 57% overall but varied markedly between the defined groups. Variation in survival within the groups was relatively limited across European regions and less than in previous years. Survival differences between men and women were small. The relative survival for patients with all lymphoid neoplasms decreased substantially after the age of 50. The proportion of 'not otherwise specified' diagnoses increased with advancing age. CONCLUSIONS: This is the first study to analyze survival of patients with lymphoid neoplasms, divided into groups characterized by similar epidemiological and clinical characteristics, providing a benchmark for more detailed analyses. This Europe-wide study suggests that previously noted differences in survival between regions have tended to decrease. The survival of patients with all neoplasms decreased markedly with age, while the proportion of 'not otherwise specified' diagnoses increased with advancing age. Thus the quality of diagnostic work-up and care decreased with age, suggesting that older patients may not be receiving optimal treatment.

Has equity in relative survival improved over time in Finland - a methodological exercise.

BACKGROUND: Population-based relative survival is widely used as a method of monitoring the success of cancer control. This success may not be relevant only for an entire country but also regional developments over time are of interest. It would not only be important that the relative survival improved but also that the differences between regions decreased over time. METHODS: In this paper the authors show how relative survival methods can be used to study such differences. In addition to standard methods, some more recently introduced approaches are used, most notably a method for checking the goodness of fit of the relative survival model. This gives confidence in the obtained results and provides additional insight when assumptions are not met. RESULTS: An analysis of cancers of the colon and ovary by cancer control region in Finland in 1953-2003 shows an overall improvement in relative survival, accompanied in colon cancer also by a decrease of differences in relative survival between the regions. Thus, the desired course was observed in colon cancer but not in cancer of the ovary. CONCLUSIONS: These results, applied to further sites, should lead to investigation of differences in cancer control policies between regions.

Incidence of cancer and antidepressant medication: record linkage study.

The consumption of antidepressants, especially selective serotonine reuptake inhibitors (SSRI) has been increasing. Because a large fraction of the population is exposed, even a small excess of risk with respect to cancer should be considered. We carried out a record linkage study in Finland utilizing nationwide databases of reimbursed medication and cancer. The study population included all antidepressant drug (AD) users in Finland who had purchased at least 1 prescription between 1998 and 2005, and who had no cancer diagnosis at the date of first purchase. A control population without AD usage (matched by age and sex) was also included. Data consisted of 418,588 pairs of individuals that cumulated 3.3 million person-years with an average of 4.0 years of follow-up. 19,365 cancer cases were observed. The most frequent cancers were breast, prostate, lung, colon, and brain cancer. In general, only few associations between the utilization of AD and cancer could be detected. Over four years exposure to AD showed a weak association with increased colon and breast cancer incidence, which could have been caused by bias. As conclusion, no clear evidence of neither beneficial nor harmful association between usage of antidepressant and cancer was found.

Incidence of cancer and statin usage--record linkage study.

The consumption of statins (HMG-CoA reductase inhibitors) has been increasing, and a substantial part of the middle-aged and elderly population use them continuously. Because a large fraction of the population is exposed, even a small excess of risk with respect to cancer should be considered. We carried out a record-linkage study in Finland utilizing nationwide databases of reimbursed statin medication and cancer. The study population included all statin users in Finland who had purchased at least 1 prescription between 1996 and 2005 and who had no cancer diagnosis at the date of first purchase. A control population without statin usage was also included. Data consisted of 472,481 pairs of individuals that cumulated 4.2 million person years with an average of 8.8 years of follow-up. Fifty thousand two hundred ninety-four cancer cases were observed. Simvastatin and atorvastatin were the most used substances. The most frequent cancers were prostate, breast, lung, colon, and rectum cancer. In general, no association between the utilization of statins and cancer could be detected. In conclusion, this study adds large-scale, population-based results about the association between statin utilization and the incidence of cancer. We found neither beneficial nor harmful associations between the usage of statins and cancer.

Risk of cancer among children of cancer patients - a nationwide study in Finland.

Cancer treatments have the potential to cause germline mutations that might increase the risk of cancer in the offspring of former cancer patients. This risk was evaluated in a population-based study of early onset cancer patients in Finland. Using the nationwide registry data, 26,331 children of pediatric and early onset cancer patients (diagnosed under age 35 between 1953 and 2004) were compared to 58,155 children of siblings. Cancer occurrence among the children was determined by linkage with the cancer registry, and the standardized incidence ratios (SIRs) were calculated comparing the observed number of cancers with that expected, based on rates in the general population of Finland. Among the 9,877 children born after their parent's diagnosis, cancer risk was increased (SIR 1.67; 95% CI 1.29-2.12). However, after removing those with hereditary cancer syndromes, this increase disappeared (SIR 1.03; 95% CI 0.74-1.40). The overall risk of cancer among the offspring of siblings (SIR 1.07; 95% CI 0.94-1.21) was the same as among the offspring of the patients with non hereditary cancer. Risk of cancer in offspring, born before their parents cancer diagnosis, was elevated (SIR 1.37, 95% CI 1.20-1.54), but removing hereditary syndromes resulted in a diminished and nonsignificant association (SIR 1.08, 95% CI 0.93-1.25). This study shows that offspring of cancer patients are not at an increased risk of cancer except when the patient has a cancer-predisposing syndrome. These findings are directly relevant to counseling cancer survivors with regard to family planning.

The effect of hospital operative volume, residual tumor and first-line chemotherapy on survival of ovarian cancer - a prospective nation-wide study in Finland.

OBJECTIVE: Our recent prospective, nation-wide study indicated better surgical outcome in ovarian cancer patients operated at university hospitals compared to other hospitals. Here we report how this is reflected in 5-year cancer-specific survival (CSS). METHODS: Detailed 5-year follow-up data were obtained on 275 patients by using a special questionnaire, and the data were verified from the Finnish Cancer Registry data. The hospitals were categorized to university and other hospitals and by the number of operations performed in 1999 (<10, 10-20, or >20 operations). Data were analyzed using the Cox's proportional hazards regression analysis. RESULTS: The study population covered 90% of the epithelial ovarian cancer patients operated in 1999, in Finland. Eighty-two percent of the patients received platinum-based chemotherapy. The percentage of patients treated with a platinum-taxane combination was higher in university hospitals (63% vs. 49%, P=0.037). The 5-year CSS was 56% and the median disease-free survival (DFS) was 33 months. In multivariate analysis prognostic factors for CSS were stage (P=0.0027), residual tumor (P=0.0001), and primary chemotherapy (P<0.0001). Hospital operative volume was associated with residual tumor (P=0.027). When hospital operative volume increased with ten patients per year, the odds ratio for no residual disease was 1.203 (95% CI 1.022-1.417). CONCLUSION: FIGO stage, residual tumor, and primary chemotherapy are significant prognostic factors for ovarian cancer. Hospital volume is associated with residual tumor. The results favor performance of ovarian cancer surgery in hospitals with higher operative volumes.

Incidence of Merkel cell carcinoma in renal transplant recipients.

BACKGROUND: The risk factors for Merkel cell carcinoma (MCC), a rare type of skin cancer, are poorly understood. Some evidence suggests that MCC is more common in individuals with abnormal immune function resulting from viral infection, autoimmune disease or organ trans- plantation. METHODS: The national Renal Transplant Registry and the Finnish Cancer Registry data were searched for recipients of a renal transplant who were diagnosed with MCC. The MCC diagnoses were confirmed using immunohistochemistry. RESULTS: Three cases of MCC were detected among 4200 individuals who underwent renal transplantation from 1967 to 2005 [expected number 0.05, standardized incidence ratio (SIR) 66, 95% CI 14-194, P <0.001]. The latency period between the transplant and detection of MCC ranged from 6 to 19 years. In all three cases, the cause of transplantation was an autoimmune disease. All three died from aggressive MCC with a survival time ranging from 0.5 to 2.1 years. CONCLUSIONS: The results indicate that the risk of MCC is greatly increased among subjects who have undergone renal transplantation. The course of the disease appears aggressive in this patient population. The physicians who treat recipients of a kidney transplant should be aware of the substantially increased risk of MCC.

Scholastic achievement of children with lymphoma or Wilms tumor at the end of comprehensive education--a nationwide, register-based study.

Cancer treatment may affect school performance. School report grades after childhood lymphomas and Wilms tumor have not been previously reported. All Finnish patients with Wilms tumor (N = 74), Hodgkin lymphoma (HL) (N = 99) and non-Hodgkin lymphoma (NHL) (N = 94) who were born in 1974-1986 and had achieved the age of 16 years were identified from the Finnish cancer registry. Population controls (N = 1329) were matched for age, gender and residence. Their 9th grade school reports were obtained from Statistics Finland. The overall average and grades for mother tongue, first foreign language, mathematics and physical education were compared between the patients and their controls. Almost all the patients (>98%) had finished their comprehensive school. NHL patients had lower overall averages than their controls (difference -0.27 grade units; 95% CI -0.39, -0.15). Irradiation or age at diagnosis did not explain this difference in NHL patients. The grades of NHL patients were significantly lower than those of their controls in each academic school subject, especially in mathematics (-0.45; 95% CI -0.63, -0.27). In mother tongue, girls with irradiation had greatest difference (-0.66, 95% CI -0.99, -0.34) to their controls. Patients with HL and Wilms tumor performed similarly or even better than their controls in all academic subjects. Grades for physical education were impaired in Wilms tumor patients (-0.20; 95% CI -0.33, -0.06). Impairment of school report grades was observed in patients with NHL. The difference to controls was greatest in mathematics. The patients with HL and Wilms tumor, who had not received any central nervous system directed therapy, achieved equally good grades as their controls in all the academic subjects.

Probability of parenthood after early onset cancer: a population-based study.

We evaluated in a population-based setting the postdiagnosis parenthood among survivors compared with the fertility patterns of siblings. Cancer patients aged 0-34 years at diagnosis were identified from the Finnish Cancer Registry (N = 25,784), and their siblings (N = 44,611) by registry linkage. Further linkage identified the offspring of the patient and sibling cohorts. The relative probabilities of parenthood for first and second births separately were estimated for male and female survivors in different diagnostic age-groups and subsites using a Cox proportional hazards model, with age as the time variable and adjusting for the birth cohort of parents. In addition, estimates were calculated for 5 diagnostic eras in all subsites combined. Compared to siblings, both female and male cancer survivors were less likely to parent at least 1 child (RR 0.46, 95% CI 0.44-0.48 and RR 0.57, 95% CI 0.54-0.60, respectively). The relative probability of parenthood was especially low in male childhood cancer survivors and female young adult cancer survivors. However, cancer patients were only slightly less likely than siblings to parent a second child, with RR 0.91, 95% CI 0.86-0.97 and RR 0.95, 95% CI 0.89-1.01 for females and males, respectively. The relative probability of parenthood increased over calendar time among young adult cancer patients. The relative probability of parenthood following early onset cancer was overall significantly reduced by approximately 50%. Parenting a second child, however, was not reduced among pediatric and adolescent survivors, and only slightly reduced among early adulthood cancer survivors compared to siblings.

Hypothyroidism among pediatric cancer patients: a nationwide, registry-based study.

The aim of the study was to determine the incidence and prevalence of hypothyroidism (HT) among childhood cancer survivors by means of register linkage. Patients extracted from the Finnish Cancer Registry data base (5,180 patients with cancer diagnosis at the age of 0-15 years, and born after 1970) were linked with thyroxin reimbursement data (Drug Reimbursement Register) and with thyroxin purchase data (prescription database) maintained by the Social Insurance Institution. At the end of follow-up, the prevalence of HT (10,509/100,000) was found to exceed that in the general population (240/100,000) for those aged <35 years. Diagnostic group (p < 0.0001) and gender (p < 0.0025) had significant effect on the risk of developing HT. Males were less prone to the development of HT. Cumulative incidence rate of HT was highest in patients with thyroid cancer (TC), Hodgkin lymphoma, central nervous system (CNS) tumors and neuroblastoma. Except in patients with TC (4.5 months) and CNS tumors (19 months), the median time for the appearance of HT was quite long, varying between 2 and 4.5 years. We consider our results valuable in providing new data for the planning of thyroid function follow-up in different diagnostic groups of childhood cancer survivors.

Risk of malignant neoplasms after liver transplantation: a population-based study.

Posttransplant malignancies have become a serious long-term complication after liver transplantation. Our aim was to compare the incidence of posttransplant cancers with national cancer incidence rates. The study included all Finnish liver transplant patients transplanted at the Helsinki University Central Hospital between 1982 and 2005. The cohort was linked with the nationwide Finnish Cancer Registry. Observed numbers of cancers were compared to site-specific expected numbers based on national cancer incidence rates stratified by age, sex, and calendar time. The standardized incidence ratios (SIRs) were calculated as observed-to-expected ratios. Thirty-nine posttransplant de novo cancers and 11 basal cell carcinomas were found in the cohort of 540 patients during 3222 person years of follow-up. The overall SIR was 2.59 (95% confidence interval 1.84-3.53). SIR was higher for males (SIR 4.16) than for females (SIR 1.74), higher among children (SIR 18.1) than among adults (SIR 5.77 for ages of 17-39 years and 2.27 for ages >/= 40 years), and more elevated in the immediate posttransplant period (SIR 3.71 at < 2 years) compared to later periods (SIR 2.46 at 2-10 years and 1.53 at >10 years). The most common cancer types were nonmelanoma skin cancer (SIR 38.5) and non-Hodgkin lymphoma (SIR 13.9). Non-Hodgkin lymphoma was associated with male gender, young age, and the immediate posttransplant period, whereas old age and antibody induction therapy increased skin cancer risk. In conclusion, cancer incidence is increased among liver transplant patients compared to the general population. This study points out the importance of cancer surveillance after liver transplantation.

Effect of surgical volume and hospital type on outcome in non-small cell lung cancer surgery: a Finnish population-based study.

OBJECTIVE: Hospital mortality and long-term survival in major cancer surgery seems to be affected by hospital related factors. We evaluated the effect of university versus non-university hospital type, and surgical volume (0-4, 5-10, 11-20, and >20 average of cases/year) on the immediate and long-term survival of surgical non-small cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: Between 1988 and 2002, the number of NSCLC resections with curative intent in Finland was 5339. Follow-up until the end of 2003 from national registries was available on 91% (4878 of 5339) of patients. RESULTS: Multivariate analysis showed that hospital mortality was unaffected by hospital type or volume, but delay of >4 months from diagnosis to surgery did have an adverse effect. Surgery at university hospitals was associated with significantly better cancer-related and overall survival, as also was surgery at very low-volume but mainly private hospitals (0-4 cases/year). CONCLUSIONS: Undergoing surgery for non-small cell lung cancer at a university hospital may offer an advantage for long-term survival, but large hospital volume in itself did not. SUMMARY: Multivariate analysis on the effect of hospital type and surgical volume on immediate and long-term survival of 4878 lung cancer surgery patients, 1988-2002, showed that surgery at university hospitals was associated with significantly better cancer-related and overall survival, but hospital mortality did not differ. Large hospital volume did not independently predict a better outcome.

Role of tobacco smoking, chewing and alcohol drinking in the risk of oral cancer in Trivandrum, India: a nested case-control design using incident cancer cases.

Oral cancer is one of the most common cancers in the world, with two-thirds of the cases occurring in developing countries. While cohort and nested case-control study designs offer various methodological strengths, the role of tobacco and alcohol consumption in the etiology of oral cancer has been assessed mainly in case-control studies. The role of tobacco chewing, smoking and alcohol drinking patterns on the risk of cancer of the oral cavity was evaluated using a nested case-control design on data from a randomized control trial conducted between 1996 and 2004 in Trivandrum, India. Data from 282 incident oral cancer cases and 1410 matched controls were analyzed using multivariate conditional logistic regression models. Tobacco chewing was the strongest risk factor associated with oral cancer. The adjusted odds ratios (ORs) for chewers were 3.1 (95% confidence interval (CI)=2.1-4.6) for men and 11.0 (95%CI=5.8-20.7) for women. Effects of chewing pan with or without tobacco on oral cancer risk were elevated for both sexes. Bidi smoking increased the risk of oral cancer in men (OR=1.9, 95%CI=1.1-3.2). Dose-response relations were observed for the frequency and duration of chewing and alcohol drinking, as well as in duration of bidi smoking. Given the relatively poor survival rates of oral cancer patients, cessation of tobacco and moderation of alcohol use remain the key elements in oral cancer prevention and control.

Osteosarcoma in Finland from 1971 through 1990: a nationwide study of epidemiology and outcome.

BACKGROUND AND PURPOSE: There have only been a few nationwide studies on the epidemiology and outcome of osteosarcoma. We report the clinical features, treatment, and prognosis of osteosarcoma in Finland for the period 1971-1990. METHODS: The study material was derived from population-based data from the national Finnish Cancer Registry. 302 osteosarcomas were reported during the study period. Histological slides could be retrieved for 199 cases and from histological re-examination, 139 (83%) of these cases were confirmed as osteosarcoma and were included in the analysis. The mean length of follow-up was 8 (0.1-28) years. RESULTS: The overall 5-year survival for the whole study population was 58%, with an improvement in survival during 1981-1990 (65%) compared to the period 1971-1980 (47%) (p=0.01). More chemotherapy was administered in the later time period. For metastasis-free survival, diagnosis in the 1970s as opposed to the 1980s (p=0.01) and large tumor size worsened outcome in univariate analysis. Patients who developed metastatic relapse within 10 months of the diagnosis had worse sarcoma-specific survival than those who developed metastases later. Limb-salvage surgery increased from 12% to 23% for patients with a peripheral tumor, with no increase in local relapses. INTERPRETATION: We recommend aggressive approach to treat recurrent disease, with a view to further improving survival. In a small country such as Finland it is necessary to concentrate treatment to only a few centers, to ensure a high quality of treatment.