Progress against lung cancer, Denmark, 2008-2022.

BACKGROUND AND PURPOSE: There has been marked progress against lung cancer in Denmark. To gain further insight into the different aspects of the improvement, we examined the stage-specific incidence rates, stage-specific survival and mortality rates. MATERIALS AND METHODS: We used information from the Danish Lung Cancer Registry on date of diagnosis and clinical stage to calculate age-standardised incidence rates and patient survival by sex, period and stage. Information about age-standardised lung cancer-specific mortality rates by sex and period was extracted from The Danish Health Data Authority. RESULTS: Firstly, the decrease in incidence rates was due to a reduction in the rates of advanced stages. Secondly, there was a gradual increase in survival across all stages, and thirdly, the mortality rates gradually decreased over time. INTERPRETATION: The improvements in survival and mortality from lung cancer were due to decreasing incidence rates of advanced cancer and improvement in survival at all stages of the disease.

Does stage of cancer, comorbidity or lifestyle factors explain educational differences in survival after endometrial cancer? A cohort study among Danish women diagnosed 2005-2009.

BACKGROUND: Several studies have documented an association between socioeconomic position and survival from gynaecological cancer, but the mechanisms are unclear. OBJECTIVE: The aim of this study was to examine the association between level of education and survival after endometrial cancer among Danish women; and whether differences in stage at diagnosis and comorbidity contribute to the educational differences in survival. METHODS: Women with endometrial cancer diagnosed between 2005 and 2009 were identified in the Danish Gynaecological Cancer Database, with information on clinical characteristics, surgery, body mass index (BMI) and smoking status. Information on highest attained education, cohabitation and comorbidity was obtained from nationwide administrative registries. Logistic regression models were used to determine the association between level of education and cancer stage and Cox proportional hazards model for analyses of overall survival. RESULTS: Of the 3638 patients identified during the study period, 787 had died by the end of 2011. The group of patients with short education had a higher odds ratio (OR) for advanced stage at diagnosis, but this was not statistically significant (adjusted OR 1.20; 95% CI 0.97-1.49). The age-adjusted hazard ratio (HR) for dying of patients with short education was 1.47 (CI 95% 1.17-1.80). Adjustment for cohabitation status, BMI, smoking and comorbidity did not change HRs, but further adjustment for cancer stage yielded a HR of 1.36 (1.11-1.67). CONCLUSION: Early detection in all educational groups might reduce social inequalities in survival, however, the unexplained increased risk for death after adjustment for prognostic factors, warrants increased attention to patients with short education in all age groups throughout treatment and rehabilitation.

Socioeconomic position and survival after lung cancer: Influence of stage, treatment and comorbidity among Danish patients with lung cancer diagnosed in 2004-2010.

BACKGROUND: To address social inequality in survival after lung cancer, it is important to consider how socioeconomic position (SEP) influences prognosis. We investigated whether SEP influenced receipt of first-line treatment and whether socioeconomic differences in survival could be explained by differences in stage, treatment and comorbidity. MATERIAL AND METHODS: In the Danish Lung Cancer Register, we identified 13 045 patients with lung cancer diagnosed in 2004-2010, with information on stage, histology, performance status and first-line treatment. We obtained age, gender, vital status, comorbid conditions and socioeconomic information (education, income and cohabitation status) from nationwide population-based registers. Associations between SEP and receipt of first-line treatment were analysed in multivariate logistic regression models and those with overall mortality in Cox regression models with stepwise inclusion of possible mediators. RESULTS: For both low- and high-stage lung cancer, adjusted ORs for first-line treatment were reduced in patients with short education and low income, although the OR for education did not reach statistical significance in men with high-stage disease. Patients with high-stage disease who lived alone were less likely to receive first-line treatment. The socioeconomic difference in overall survival was partly explained by differences in stage, treatment and comorbidity, although some differences remained after adjustment. Among patients with high-stage disease, the hazard ratio (HR) for death of those with low income was 1.12 (95% CI 1.05-1.19) in comparison with those with high income. Among patients with low-stage disease, those who lived alone had a 14% higher risk for dying (95% CI 1.05-1.25) than those who lived with a partner. The differences in risk for death by SEP were greatest in the first six months after diagnosis. CONCLUSION: Socioeconomic differences in survival after lung cancer are partly explained by social inequality in stage, first-line treatment and comorbidity. Efforts should be made to improve early diagnosis and adherence to first-line treatment recommendations among disadvantaged lung cancer patients.

Socioeconomic position and stage at diagnosis of head and neck cancer - a nationwide study from DAHANCA.

BACKGROUND: Socioeconomic differences in survival after head and neck squamous cell carcinoma (HNSCC) are among the greatest for any malignancy. To improve our understanding of the mechanisms by which socioeconomic position influences HNSCC survival, we investigated the association between socioeconomic position and advanced stage HNSCC at diagnosis. MATERIAL AND METHODS: Men and women with HNSCC diagnosed between 1992 and 2008 were identified in the Danish Head and Neck Cancer Group (DAHANCA) database, which contains detailed information on all cases of HNSCC treated in Denmark. Individual information on the following four socioeconomic indicators: highest attained educational level, cohabitation status, disposable income and degree of urbanisation were obtained from Statistics Denmark. For the 9683 cases on which there was full information, we estimated odds ratios (ORs) for a diagnosis of advanced stage (TNM III-IV) HNSCC in multivariate logistic regression models by site (glottic, non-glottic larynx, oropharynx, hypopharynx and oral cancer), with adjustment for age, gender, period of diagnosis, education, income, cohabitation status, degree of urbanisation and comorbidity in accordance with a causal diagram. RESULTS: For all HNSCC sites, the ORs for advanced stage at diagnosis were increased for patients with low income and for men living alone. For glottic and oral cancers, the ORs for advanced stage HNSCC increased systematically by decreasing length of education. Increased ORs were found for hypopharynx cancer patients living in rural areas or provincial cities. Having one or more comorbid conditions was associated with an increased OR for advanced stage oral cancer but with a decreased OR for oropharynx cancer. CONCLUSION: In this nationwide population-based study, socioeconomic differences in stage at diagnosis were found for all HNSCC subsites. Focus on the high risk for advanced stage HNSCC among vulnerable patients may be beneficial during referral and diagnosis in order to improve HNSCC outcomes.

Socioeconomic position and survival after stroke in Denmark 2003 to 2012: nationwide hospital-based study.

BACKGROUND AND PURPOSE: The risk for stroke is higher in low-income groups. It is not clear whether these groups also have a higher risk for death after a stroke. METHODS: We studied survival in relation to income and level of education in all patients aged >40 years admitted to hospital for stroke in Denmark in 2003 to 2012. All Danish hospitals report data to the Danish Stroke Register for all patients admitted for acute stroke, including age, sex, stroke severity, subtype, and a cardiovascular risk profile. Information on income and education was obtained from Statistics Denmark; deaths from all causes from the Civil Registration Registry. RESULTS: Information on education and disposable income was available for 56 581 Danes hospitalized for stroke during the 9.5-year study period. Median length of follow-up was 3.1 years. For the entire follow-up period, there was a significant, stepwise, independent relation between income and risk for death after stroke, which was 30% higher for the lowest than for the highest quintile income group (relative risk, 0.70, 95% confidence interval, 0.65-0.74). People aged <65 years with basic education had a slightly higher risk for death than those with the longest (relative risk, 1.15; 95% confidence interval, 1.02-1.30). Death within 1 month was not associated with income or education. CONCLUSIONS: The survival of patients with low income was reduced by 30% as compared with those with high income. Education had only a modest effect and only in patients aged <65 years. The impact of socioeconomic position was on late but not on early poststroke death.

All-cause mortality among men whose cohabiting partner has been diagnosed with cancer.

BACKGROUND: Previous studies suggest that spouses of cancer patients are at increased risk for several chronic diseases. We investigated mortality in relation to cancer morbidity in the stable female partner. METHODS: We established a national retrospective cohort study of 1,422,131 men who had lived continuously with the same partner for at least 5 years and used Cox regression analysis to assess the association between experiencing cancer in a cohabiting partner and all-cause mortality. RESULTS: The risk for death was only slightly elevated among men whose partner had cancer than for men whose partner remained free of cancer (hazard ratio = 1.03; 95% confidence interval = 1.01-1.05). CONCLUSIONS: Although a cancer diagnosis in a spouse might be associated with considerable distress, our study indicates that the risk for death differs only slightly between men living with a partner with cancer and those living with a partner without cancer.

Effect of mindfulness-based stress reduction on sleep quality: results of a randomized trial among Danish breast cancer patients.

UNLABELLED: The prevalence of sleep disturbance is high among cancer patients, and the sleep problems tend to last for years after the end of treatment. As part of a large randomized controlled clinical trial (the MICA trial, NCT00990977) of the effect of mindfulness-based stress reduction (MBSR) on psychological and somatic symptoms among breast cancer patients, the aim of the current study was to evaluate the effect of MBSR on the secondary outcome, 'sleep quality'. MATERIAL AND METHODS: A total of 336 women operated on for breast cancer stage I-III 3-18 months previously were randomized to MBSR (n = 168) or treatment as usual (n = 168); both groups received standard clinical care. The intervention consisted of an eight-week MBSR program (psycho-education, meditation and gentle yoga). Sleep quality was assessed on the Medical Outcome Study sleep scale at baseline, after the intervention and at six- and 12-months' follow-up. RESULTS: The mean sleep problem scores were significantly lower in the MBSR group than in controls immediately after the intervention. Quantile regression analyses showed that the effect was statistically significant only for the participants represented by the lower percentile of change between baseline and post-intervention, i.e. those who had more sleep problems; the MBSR group had a significantly smaller increase in sleep problems than the control group. After the 12-month follow-up, there was no significant between-group effect of MBSR on sleep quality in intention-to-treat analyses. CONCLUSION: MBSR had a statistically significant effect on sleep quality just after the intervention but no long-term effect among breast cancer patients. Future trials in which participation is restricted to patients with significant sleep problems are recommended for evaluating the effect of MBSR on sleep quality.

Affiliation to the work market after curative treatment of head-and-neck cancer: a population-based study from the DAHANCA database.

OBJECTIVES: Survivors of squamous cell carcinoma of the head and neck (HNSCC) are more severely affected in regard to affiliation to the work market than other cancer survivors. Few studies have investigated associations between socioeconomic and disease-related factors and work market affiliation after curative treatment of HNSCC. We investigated the factors for early retirement pension due to disability and unemployment in patients who had been available for work one year before diagnosis. METHODS: In a nationwide, population-based cohort study, data on 2436 HNSCC patients treated curatively in 1992-2008 were obtained from the Danish Head and Neck Cancer Group database and linked to Danish administrative population-based registries to obtain demographic and socioeconomic variables. We used multivariate logistic regression models to assess associations between socioeconomic factors (education, income and cohabitating status), cancer-specific variables such as tumour site and stage, comorbidity, early retirement pension and unemployment, with adjustment for age, gender and year of diagnosis. RESULTS: Short education [odds ratio (OR) 4.8; 95% confidence interval (CI) 2.2-10.4], low income (OR 3.2; 95% CI 1.8-5.8), living alone (OR 3.0; 95% CI 2.1-4.4) and having a Charlson comorbidity index score of 3 or more (OR 5.9; 95% CI 3.1-11) were significantly associated with early retirement overall and in all site groups. For the subgroup of patients who were employed before diagnosis, the risk pattern was similar. Tumour stage was not associated with early retirement or unemployment. CONCLUSIONS: Cancer-related factors were less strongly associated with early retirement and unemployment than socioeconomic factors and comorbidity. Clinicians treating HNSCC patients should be aware of the socioeconomic factors related to work market affiliation in order to provide more intensive social support or targeted rehabilitation for this patient group.

Delayed breast implant reconstruction: is radiation therapy associated with capsular contracture or reoperations?

We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during the period between 1999 and 2006. A history of radiation therapy was associated with increased risk of severe capsular contracture for 1- and 2-stage procedures, with adjusted hazard ratios (HR) of 3.3 (95% confidence interval [CI]: 0.9-12.4) and 7.2 (95% CI: 2.4-21.4), respectively. Similarly, a history of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy.

Thin or early melanoma, risk factors and associated mortality.

INTRODUCTION: The incidence of thin and early-stage melanoma is increasing in many populations, but the clinical significance of these lesions remains partly unknown. METHODS: Firstly, melanoma deaths in Denmark (2009-2018) were followed back to establish melanoma debut in these persons. Secondly, using national registries of cancer incidence and mortality, 27,036 persons with thin or early-stage melanoma were followed-up for melanoma death. RESULTS: It is estimated that in 11% of the persons who died from melanoma, the debut was a thin or early-stage melanoma. On follow-up of persons with thin or early-stage melanoma, the 20-year risk of dying from melanoma was 3%. CONCLUSION: The absolute risk of melanoma death after a diagnosis with thin or early-stage melanoma is low. A subgroup of patients who are at a high risk may possibly be identified by a combination of stage, thickness, ulceration and dermal mitoses. FUNDING: none. TRIAL REGISTRATION: not relevant.

Regional and socio-economic variation in survival after glioblastoma in Denmark, 2013-2018.

INTRODUCTION: Glioblastoma is the most frequent primary brain tumour in adults. In Denmark, the treatment of glioblastoma is centralised to four neurosurgical and oncological departments located in four of the five Danish administrative regions. The aim of this study was to examine the regional and socioeconomic variation in survival after a diagnosis of glioblastoma in Denmark. METHODS: We included 1,731 patients with histologically confirmed glioblastoma from 2013 to 2018 registered in the Danish Neuro-oncology Registry. The data sources were the Danish National Registries. The exposure was region of residence at diagnosis and household income in the year before diagnosis. Follow-up was initiated at diagnosis and concluded at death or end-of-follow-up on 15 July 2019. Cox regression was used to examine overall mortality by exposure. RESULTS: With adjustment for age, sex, year of diagnosis and comorbidity, mortality rates of glioblastoma patients varied significantly between regions and were lowest in the Region of Southern Denmark and highest in the Capital Region (hazard ratio = 0.79; 95% confidence interval: 0.68-0.91, compared with the Capital Region). Further adjustment for surgical resection attenuated the regional differences in mortality. Income was not a predictor of survival. CONCLUSIONS: We found significant regional variation in survival after a diagnosis of glioblastoma. Differences in treatment patterns between regions may explain part of this mortality variation. Household income and education level did not explain the regional differences. FUNDING: none. TRIAL REGISTRATION: not relevant.

Long-term mobile phone use and the risk of vestibular schwannoma: a Danish nationwide cohort study.

Vestibular schwannomas grow in the region within the brain where most of the energy by radiofrequency electromagnetic fields from using mobile phones is absorbed. The authors used 2 Danish nationwide cohort studies, one a study of all adult Danes subscribing for a mobile phone in 1995 or earlier and one on sociodemographic factors and cancer risk, and followed subjects included in both cohorts for occurrence of vestibular schwannoma up to 2006 inclusively. In this study including 2.9 million subjects, a long-term mobile phone subscription of ≥11 years was not related to an increased vestibular schwannoma risk in men (relative risk estimate = 0.87, 95% confidence interval: 0.52, 1.46), and no vestibular schwannoma cases among long-term subscribers occurred in women versus 1.6 expected. Vestibular schwannomas did not occur more often on the right side of the head, although the majority of Danes reported holding their mobile phone to the right ear. Vestibular schwannomas in long-term male subscribers were not of larger size than expected. Overall, no evidence was found that mobile phone use is related to the risk of vestibular schwannoma. Because of the usually slow growth of vestibular schwannoma and possible diagnostic delay, further surveillance is indicated.

Socioeconomic position and breast reconstruction in Danish women.

UNLABELLED: Few studies have been conducted on the socioeconomic position of women undergoing breast reconstruction, and none have been conducted in the Danish population. We investigated the association between educational level and breast reconstruction in a nationwide cohort of Danish women with breast cancer. MATERIAL AND METHODS: From nationwide registers, 13 379 women aged 30-80 years who had been treated by mastectomy for breast cancer in Denmark in 1999-2006 were identified and followed up through November 2009. Multivariate logistic regression models were used to investigate the simultaneous influence of educational level on the likelihood of having immediate or delayed (up to three years after mastectomy) breast reconstruction, with adjustment for age, breast cancer characteristics, comorbidity, socioeconomic variables and availability of plastic surgery services at each woman's affiliated hospital. RESULTS: The odds ratios (ORs) for both immediate and delayed breast reconstruction increased significantly with level of education. Being affiliated to a hospital with a plastic surgery department increased the likelihood of both immediate (adjusted OR, 4.02; 95% confidence interval [CI], 2.81-5.75) and delayed breast reconstruction (adjusted OR, 1.41; 95% CI, 1.26-1.66). There was no association between education and breast reconstruction among 30-44 year old women, regardless of type of breast reconstruction; however, medium or higher education was significantly associated with a fourfold increase in the OR for immediate breast reconstruction in women aged 45-59 years and a more than twofold increase in the OR for delayed breast reconstruction in women aged 60-80 years compared to women with short education. CONCLUSION: Increasing education was associated with increasing odds for having immediate or delayed breast reconstruction, but only in the older age groups. The offer of breast reconstruction appears to be unequally distributed in Denmark, and living in an area where the hospital has a plastic surgery department significantly increased the odds for having breast reconstruction.

The clinical course of immediate breast implant reconstruction after breast cancer.

BACKGROUND: The number of women suitable for breast conserving treatment as well as immediate reconstruction after breast cancer has been increasing, and studies of complications hereafter are needed. MATERIAL AND METHODS: The cohort was identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during the period 1999 to 2006; 167 women with 189 immediate breast reconstructions (40 one-stage and 149 two-stage procedures) after breast cancer without a history of radiation therapy. The women were followed for complications until November 2009. Cumulative incidence risks were computed for infection, hematoma, seroma, severe capsular contracture (modified Baker III and IV), extrusion of the implant, implant rupture, asymmetry/displacement of the implant, any complication, and reoperation. In addition, we compared the postoperative course of immediate two-stage procedures with delayed two-stage procedures. RESULTS: The overall eight-year risk estimates for the immediate procedures were 76.4% for any complication, 5.3% for severe capsular contracture, 29.5% for displacement/asymmetry of the implant and 40.6% for reoperation. Significantly higher risk for reoperation was observed after immediate one-stage than after two-stage procedures. For immediate two-stage procedures acute complications such as infection, seroma and hematoma were higher in the expansion period than after the second planned surgery. Higher risks for acute complications were observed after immediate than after delayed two-stage procedures. CONCLUSION: Immediate breast implant reconstruction was found to have substantial risks of complications in non-radiated women, which should be considered in the guidance of breast cancer patients before choosing reconstructive procedure.

Uncertain added value of Global Trigger Tool for monitoring of patient safety in cancer care.

INTRODUCTION: Monitoring patient safety is a challenging task. The lack of a golden standard has contributed to the recommendation and introduction of several methods. In 2000 the Danish Lung Cancer Registry (DLCR) was established to monitor the clinical management of lung cancer. In 2008 the Global Trigger Tool (GTT) was recommended in Denmark as a tool for the monitoring of patient safety. Ideally, the recommendation of a new tool should be preceded by a critical assessment of its added value. MATERIAL AND METHODS: Data on complications related to lung cancer surgery from the Department of Cardiothoragic Surgery at Odense University Hospital were collected using the DLCR and the GTT in 2008. The capacity of these two methods to identify complications is compared and discussed. RESULTS: A total of 59 complications were registered in the DLCR, while 58 complications were registered using the GTT. The two methods were equally good at identifying complications, but the DLCR seemed to be borderline significantly better at detecting arrhythmia, while the GTT was significantly better at detecting "other events". CONCLUSION: Nearly half of the adverse events identified with the GTT were complications which were also registered by type in the DLCR. The two methods were almost equally good at identifying specific types of complications, but the GTT identified more "other events". The majority of these events were well-known to clinicians. The comparison illustrates why the implementation of new methods should be preceded by critical assessment. In this case, it is crucial to assess whether the current method should be modified by the addition of more patient safety indicators rather than by introducing a new method that partly duplicates existing data.

Regional and socio-economic variation in survival after a pancreatic cancer diagnosis in Denmark.

INTRODUCTION: Pancreatic cancer is among the most lethal malignancies with a five-year survival of about 5%, and the only curative treatment is surgical resection. Denmark consists of five governmental regions and has four surgical centres. Our aim was to explore the regional and socio-economic differences in overall survival following a pancreatic cancer diagnosis in Denmark. METHODS: We included a total of 5,244 pancreatic cancer patients (WHO International Classification of Diseases, tenth version C25) registered in the Danish Pancreatic Cancer Database during 2012-2017. The data sources used were the Danish Civil Registration System, the Danish National Patient Registry and the Danish national registers on education and income at Statistics Denmark. Cox regression analysis was used to examine all-cause mortality of pancreatic cancer patients by region of residence and socio-economic status. RESULTS: Compared to The Capital Region, there was an excess mortality in the Central Denmark Region and the North Denmark Region in both men and women, whereas no increased mortality was observed in the Region of Southern Denmark or in Region Zealand. Estimates were adjusted for age, year of diagnosis and comorbidity. Adjustment for surgical resection greatly attenuated the variation in survival between the regions. CONCLUSIONS: We found significant differences in overall survival across the five Danish regions following a diagnosis of pancreatic cancer. The regional variation in survival was largely attributable to differences in the propensity to use surgical resection. FUNDING: none. TRIAL REGISTRATION: not relevant.

Regional and socioeconomic variation in survival of melanoma patients in Denmark.

INTRODUCTION: This article explores variation in survival and mortality of Danish melanoma patients from 2012 to 2017 in relation to their region of residence and socioeconomic status. METHODS: Data were extracted from The Danish Melanoma Database, a clinical register, based on reports from hospital departments and dermatologists, and designed for quality improvement. The analysis included covariates at the person and tumour level. A cohort analysis was implemented to quantify the variations and identify the underlying mechanisms behind regional and socioeconomic variations in mortality of melanoma patients. RESULTS: The mortality of melanoma patients varied between the five regions with mean hazard ratios (95% confidence interval) of 1.36 (1.07-1.74) in men and 1.44 (1.08-1.92) in women between the regions with highest and lowest mortality. Mortality was highest in the patients with the lowest income and shortest education. Regional variation in mortality was attributable to underlying variation in tumour stage and thickness, and it was not confounded by other covariates. CONCLUSIONS: The two regions with the lowest mortality (highest survival) had high absolute incidence rates of stage IA and thin melanomas, indicating a high level of diagnostic activity in these regions. There was no regional variation in the incidence of advanced melanoma. The optimal level of diagnostic investigation of skin lesions has yet to be established. FUNDING: none. TRIAL REGISTRATION: not relevant.

Risk of adhesive bowel obstruction after abdominal surgery. A national cohort study of 665,423 Danish women.

BACKGROUND: Adhesive bowel obstruction is associated with considerable morbidity and mortality, but the magnitude of the risk is debated. METHOD: In a national cohort of all Danish women with an abdominal operation (N = 665,423) between 1977 and 2013, the risk of adhesive bowel obstruction was assessed by Cox multiple regression. Covariates were the number of abdominal operations, the surgical methods, the anatomical site involved, and the calendar year. RESULTS: In the cohort, 1.4% experienced an episode of adhesive bowel obstruction. The risk increased 33-43% during the study period, was lower after gynecological and obstetrical procedures compared to gastrointestinal (HR 0.36 [0.34-0.38]), lower after laparoscopic compared to laparotomic surgery (HR 0.51 [0.48-0.54]) and increased proportionally after each additional operation. CONCLUSIONS: The risk of adhesive bowel obstruction after abdominal operations depends on the site of earlier operations, the method of access and the number of earlier operations.

Influence of socioeconomic factors and region of residence on cancer stage of malignant melanoma: a Danish nationwide population-based study.

BACKGROUND: Socioeconomic differences in survival after melanoma may be due to late diagnosis of the disadvantaged patients. The aim of the study was to examine the association between educational level, disposable income, cohabitating status and region of residence with stage at diagnosis of melanoma, including adjustment for comorbidity and tumor type. METHODS: From The Danish Melanoma Database, we identified 10,158 patients diagnosed with their first invasive melanoma during 2008-2014 and obtained information on stage, localization, histology, thickness and ulceration. Sociodemographic information was retrieved from registers of Statistics Denmark and data on comorbidity from the Danish National Patient Registry. We used logistic regression to analyze the associations between sociodemographic factors and cancer stage. RESULTS: Shorter education, lower income, living without partner, older age and being male were associated with increased odds ratios for advanced stage of melanoma at time of diagnosis even after adjustment for comorbidity and tumor type. Residence in the Zealand, Central and Northern region was also associated with advanced cancer stage. CONCLUSION: Socioeconomically disadvantaged patients and patients with residence in three of five health care regions were more often diagnosed with advanced melanoma. Initiatives to increase early detection should be directed at disadvantaged groups, and efforts to improve early diagnosis of nodular melanomas during increased awareness of the Elevated, Firm and Growing nodule rule and "when in doubt, cut it out" should be implemented. Further studies should investigate regional differences in delay, effects of number of specialized doctors per inhabitant as well as differences in referral patterns from primary to secondary health care across health care regions.