Head and neck cancer in Norway

Childhood central nervous system tumors and leukemia: Incidence and familial risk. A comparative population-based study in Utah and Norway

BACKGROUND

In this study, we aimed to evaluate incidence rates and family risk of the most common childhood cancers, tumors in the central nervous system (CNS), and leukemia among individuals from Norway and individuals with Scandinavian ancestry living in Utah.

METHODS

We used the Utah Population Database and the Norwegian National Population Register linked to Cancer registries to identify cancers in children born between 1966 and 2015 and their first-degree relatives. We calculated incidence rates and hazards ratios.

RESULTS

The overall incidence of CNS tumors increased with consecutive birth cohorts similarly in Utah and Norway (both P < 0.001). Incidence rates of leukemia were more stable and similar in both Utah and in Norway with 4.6/100 000 person-years among children (<15 years) born in the last cohort. A family history of CNS tumors was significantly associated with risk of childhood CNS tumors in Utah HR = 3.05 (95% CI 1.80-5.16) and Norway HR = 2.87 (95% CI 2.20-3.74). In Norway, children with a first-degree relative diagnosed with leukemia had high risk of leukemia (HR = 2.39, 95% CI 1.61-3.55).

CONCLUSION

Despite geographical distance and assumed large lifestyle differences, two genetically linked pediatric populations show similar incidences of CNS tumors and leukemia in the period 1966-2015. CNS tumors and leukemia aggregated in families in both countries.

An assessment of the quality of the I-DSD and the I-CAH registries - international registries for rare conditions affecting sex development

BACKGROUND

With the proliferation of rare disease registries, there is a need for registries to undergo an assessment of their quality against agreed standards to ensure their long-term sustainability and acceptability.This study was performed to evaluate the I-DSD and I-CAH Registries and identify their strengths and weaknesses.

METHODS

The design and operational aspects of the registries were evaluated against published quality indicators. Additional criteria included the level of activity, international acceptability of the registries and their use for research.

RESULTS

The design of the I-DSD and I-CAH Registries provides them with the ability to perform multiple studies and meet the standards for data elements, data sources and eligibility criteria. The registries follow the standards for data security, governance, ethical and legal issues, sustainability and communication of activities. The data have a high degree of validity, consistency and accuracy and the completeness is maximal for specific conditions such as androgen insensitivity syndrome and congenital adrenal hyperplasia. In terms of research output, the external validity is strong but the wide variety of cases needs further review. The internal validity of data was condition specific and highest for conditions such as congenital adrenal hyperplasia. The shift of the registry from a European registry to an international registry and the creation of a discrete but linked CAH registry increased the number of users and stakeholders as well as the international acceptability of both registries.

CONCLUSIONS

The I-DSD and I-CAH registries comply with the standards set by expert organisations. Recent modifications in their operation have allowed the registries to increase their user acceptability.

Time trends in pharyngeal cancer incidence in Norway 1981-2005: a subsite analysis based on a reabstraction and recoding of registered cases

OBJECTIVE

Incidence rates of oropharyngeal squamous cell carcinoma (SCC) have been reported to be increasing in several countries in recent decades, contrasting with trends of SCCs diagnosed in neighboring anatomical sites. We investigated whether changes in classification systems and/or coding/registration practices might explain the trends in Norway, focusing on changes in oropharyngeal cancer.

METHODS

Trends in cancers of the oropharynx, base of tongue, nasopharynx, hypopharynx were graphically presented for the period 1981-2005, before and after recoding. Age-period-cohort and future prediction models were fitted to oropharyngeal SCC incidence.

RESULTS

A total of 85 (3.7%) of the 2315 pharyngeal cancers required recoding. Rates of oropharyngeal cancer in Norway were consistently two to three times higher in men, with rapid increases in both men (5% per annum) and women (4.2% per annum). Assuming generational effects, male cohorts born 1915-1950 were at increasingly higher risk of the disease. The number of oropharyngeal cancer cases is expected to double in Norway by 2020.

CONCLUSIONS

The trends were not considered materially biased by potential artefacts. The increasingly higher proportion of oropharyngeal SCC cancers is more likely explained by other factors, including an increasing high-risk HPV prevalence among recent cohorts. These results will likely have consequences on treatment and health care provision in the near future.

Parenthood after cancer - a population-based study

Many cancer forms today have good prognosis, and parenthood after cancer diagnosis and treatment has become a central research topic. Previous research has mainly focused on reproductive cancers, and few population-based studies exist. The effect of several cancer forms on fertility at a population level was explored. Discrete-time hazard regression models were used to analyse register and census data for complete Norwegian birth cohorts. Men and women 17-44 years in the period 1965-2001 were included. Models for first- and higher-order birth rates, for men and women, were estimated.Overall, first-birth rates among persons with cancer were reduced by only about 25% when compared with the general population. Male cancer survivors' second- and third-birth rates were similarly reduced, whereas higher-order birth rates for females were 36% below those of the general population. Significant decreases in cancer survivors' fertility disadvantage relative to the general population were seen from 1965 to 2001. Reductions in fertility were most pronounced for reproductive cancer forms, presumably related to subfecundity. However, also cancer forms unrelated to reproductive function led to reduced fertility, perhaps suggesting underlying social mechanisms. This is further supported by the difference in probability between first and subsequent births observed for women.

Early detection of oral cancer – Is dielectrophoresis the answer?

The early detection of oral squamous cell carcinoma by non-invasive methods has the potential to hasten diagnosis and thus lessen the morbidity associated with tumour therapy. Dielectrophoresis (DEP) can non-invasively determine electrophysiological parameters such as conductivity and permittivity of cellular cytoplasm and membrane. The present study demonstrates that DEP can be utilised to characterise H357 and UP cells and reveals that there are significant differences in these parameters between malignant and more normal epithelial cell lines. The present results suggest that DEP has potential for the early detection of cancerous from non-cancerous cells in a clinical setting.

Improved short-term survival for advanced ovarian, tubal, and peritoneal cancer patients operated at teaching hospitals

The aim of this study was to study the impact of hospital level and surgical skill on short-term survival of advanced ovarian, tubal, and peritoneal cancer patients in a prospective population-based study. All 198 women with a diagnosis of advanced epithelial invasive ovarian, tubal, and peritoneal cancer in Norway who underwent surgery during 2002 were included in this study. The data were derived from notifications to the Norwegian Cancer Registry and from medical, surgical, and histopathologic records. The hospitals were grouped into teaching and nonteaching hospitals (NTH), and the operating physicians were classified according to specialty (specialist gynecologist, gynecologist, and surgeon). The follow-up period was from 455 to 820 days. The short-term survival at 450 days was 79% for women operated at teaching hospitals (TH) and 62% at NTH (P= 0.02). After simultaneous adjustment for seven prognostic factors and residual disease, the risk of death within 600 days at NTH was unchanged compared to TH, hazard ratio 1.83. The women operated on by specialist compared to general gynecologists had a 20% increased short-term survival (P < 0.0001). TH and specialist gynecologists achieved better short-term survival of patients operated for advanced ovarian, tubal, and peritoneal cancer. Centralization and specialization of ovarian cancer surgery might improve the outcome for this patient group.

The lethal effect of bis-type azridinylnaphthoquinone derivative on oral cancer cells (OEC-M1) associated with anti-apoptotic protein bcl-2

Several drugs of aziridinylbenzoquinone analogs have undergone clinical trials as potential antitumor drugs. These bioreductive compounds are designed to kill tumor cells preferentially within the hypoxic microenvironment. From our previous reported data, it was found that the synthesized 2-aziridin-1-yl-3-[(2-[2-[(3-aziridin-1-yl-1,4-dioxo-1,4-dihydronaphthalen-2-yl)thio]ethoxy]ethyl)thio]naphthoquinone (AZ-1) is a bioreductive compound with potent lethal effect on oral cancer cell, OEC-M1. It was found in this study that the lethal effect of the oral cancer cell lines OEC-M1 induced by AZ-1 was mediated through the cell cycle arrest and apoptosis pathway. The LC50 values of OEC-M1 and KB cells induced by AZ-1 compound were 0.72 and 1.02 microM, respectively, which were much lower than that of normal fibroblast cells (SF with LC50 = 5.6 microM) with more than 90% of normal fibroblasts surviving as compared to control at a concentration of AZ-1 as high as 2 microM. It was interesting to note that the LC50 of monotype diaziridinylbenzoquinone compound, diaziquone (AZQ), was 50 microM on OEC-M1 cells. Comparing the cytotoxicity of AZ-1 and AZQ on OEC-M1 cells, AZ-1 is approximately 70 times more potent than AZQ. By using Western blot, both G2/M phase cell cycle arresting protein, cyclin B, and anti-apoptotic protein, bcl-2, were expressed in OEC-M1 cell when the concentrations of AZ-1 were increased from 0.125 to 0.5 microM and then decreased from 1 to 2 microM of AZ-1 treatment as compared with control for 24 h. Both proteins were expressed most abundantly at 0.5 microM AZ-1. However, the expression of bcl-2 protein in OEC-M1 was significantly decreasing in a dose-dependent manner and was only about 50% protein level at 2 microM AZ-1 for 48h as compared with control. The cell survival check protein p53 increased from 1.72- to 2.8-fold and 1.36- to 2.16-fold at concentrations of AZ-1 from 0.125 to 2.0 microM in a dose-dependently increasing manner on OEC-M1 as compared with control for 24 and48 h treatments, respectively. The apoptotic-related phenomena were observed, which included apoptotic body formation and the enzyme activity change of caspase-3. The apoptotic bodies and caspase-3 activity of OEC-M1 were induced only at 2 microM AZ-1 for a 24h treatment, yet apoptotic body formation was observed at as low as 0.5 microM AZ-1 and in a dose-dependently increasing manner for a 48 h treatment. The caspase-3 activity was increased 20.6%, 26.8%, and 84.2%, respectively, at 0.5, 1, and 2muM concentrations of AZ-1 for a 48 h treatment as compared with control. These results indicate that AZ-1 induced the cell death of OEC-M1 through the G2/M phase arrest of cell cycle and anti-apoptosis first and then apoptosis following a 48 h treatment. All of the pathway might be associated with bcl-2 and p53 protein expression. We propose that the AZ-1 could be used as anti-oral cancer drug for future studies with animal models.

Non-steroidal anti-inflammatory drugs and the risk of oral cancer: a nested case-control study

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) seem to prevent several types of cancer, but could increase the risk of cardiovascular complications. We investigated whether use of NSAIDs was associated with a change in the incidence of oral cancer or overall or cardiovascular mortality.

METHODS

We undertook a nested case-control study to analyse data from a population-based database (Cohort of Norway; CONOR), which consisted of prospectively obtained health data from all regions of Norway. People with oral cancer were identified from the 9241 individuals in CONOR who were at increased risk of oral cancer because of heavy smoking (15 pack-years), and matched controls were selected from the remaining heavy smokers (who did not have cancer).

FINDINGS

We identified and analysed 454 (5%) people with oral cancer (279 men, 175 women, mean [SD] age at diagnosis 63.3 [13.2] years) and 454 matched controls (n=908); 263 (29%) had used NSAIDs, 83 (9%) had used paracetamol (for a minimum of 6 months), and 562 (62%) had used neither drug. NSAID use (but not paracetamol use) was associated with a reduced risk of oral cancer (including in active smokers; hazard ratio 0.47, 95% CI 0.37-0.60, p<0.0001). Smoking cessation also lowered the risk of oral cancer (0.41, 0.32-0.52, p<0.0001). Additionally, long-term use of NSAIDs (but not paracetamol) was associated with an increased risk of cardiovascular-disease-related death (2.06, 1.34-3.18, p=0.001). NSAID use did not significantly reduce overall mortality (p=0.17).

INTERPRETATION

Long-term use of NSAIDs is associated with a reduced incidence of oral cancer (including in active smokers), but also with an increased risk of death due to cardiovascular disease. These findings highlight the need for a careful risk-benefit analysis when the long-term use of NSAIDs is considered.

Oral cancer prevention and the evolution of molecular-targeted drug development

The multifaceted rationale for molecular-targeted prevention of oral cancer is strong. Oral cancer is a major global threat to public health, causing great morbidity and mortality rates that have not improved in decades. Oral cancer development is a tobacco-related multistep and multifocal process involving field carcinogenesis and intraepithelial clonal spread. Biomarkers of genomic instability, such as aneuploidy and allelic imbalance, can accurately measure the cancer risk of oral premalignant lesions, or intraepithelial neoplasia (IEN). Retinoid-oral IEN studies (eg, of retinoic acid receptor-beta, p53, genetic instability, loss of heterozygosity, and cyclin D1) have advanced the overall understanding of the biology of intraepithelial carcinogenesis and of preventive agent molecular mechanisms and targets-important advances for monitoring preventive interventions and assessing cancer risk and pharmacogenomics. Clinical management of oral IEN varies from watchful waiting to complete resection, although complete resection does not prevent oral cancer in high-risk patients. New approaches, such as interventions with molecular-targeted agents and agent combinations in molecularly defined high-risk oral IEN patients, are urgently needed to reduce the devastating worldwide consequences of oral cancer.

Criteria to rationalize population screening to control oral cancer

Screening populations for the early detection of asymptomatic malignancies and potential malignancies are intuitively attractive strategies to control or reduce the burden of oral cancer on society. Subsequent preventive and/or therapeutic measures must, however, be substantiated by prospective randomized controlled trials (RCT) to markedly improve patient outcomes to reconcile such usages of 'scarce' healthcare resources. This strategic objective is more likely to be achieved by adopting the precedent established by cardiology, where prevention is emphasized over the treatment of occult lesions. For example, the screening identification of individuals at high oral carcinogenic risk will offer potential educational opportunities to change their behaviors, and/or optimize the implementation of contemporary preventive and therapeutic measures for non-compliant individuals. The imperative to substantiate the effectiveness of the screening assays (tests) by prospective RCT also cannot be ignored to safeguard the public against potential false-negative or false-positive diagnoses.

Suicide Risk in Cancer Patients From 1960 to 1999

Purpose

Suicide risk is reportedly higher for cancer patients than for the general population, but estimates vary and analyses of trends are few. The aim of the present study was to determine whether cancer patients had a higher suicide risk between 1960 and 1999.

Patients and Methods

A cohort comprising patients from the Cancer Registry of Norway 1960 to 1997 was linked to suicide diagnosis in the Register of Deaths at Statistics Norway and observed during 1960 to 1999. The cohort consisted of all cancer patients registered in the Cancer Registry of Norway 1960 to 1997 (N = 490,245 patients with 520,823 cancer diagnoses). Suicide was defined according to death certificates based on the International Classification of Diseases (versions 7, 8, 9, and 10).

Results

During the period, 589 cancer patients (407 males and 182 females) committed suicide. The relative risk was elevated for males and females, with standardized mortality ratios (SMRs) of 1.55 (95% CI, 1.41 to 1.71) and 1.35 (95% CI, 1.17 to 1.56), respectively. Risk was highest in the first months after diagnosis. For both sexes, there was a significant decrease in the relative suicide risk over decades. The risk was markedly increased among male patients with cancer of respiratory organs (SMR, 4.08; 95% CI, 2.96 to 5.47). Otherwise, the SMRs varied from 0.76 to 3.67 across cancer types.

Conclusion

Cancer may be a risk factor for suicide, particularly shortly after diagnosis. However, the relative risk gradually decreased during the period 1960 to 1999.

The influence of resection and aneuploidy on mortality in oral leukoplakia

BACKGROUND

Although the standard treatment of oral leukoplakia ranges from watchful waiting to complete resection, the value of these approaches is unknown.

METHODS

We studied the relations among resection, ploidy status, and death from cancer in 103 patients with diploid dysplastic oral leukoplakia, 20 patients with tetraploid lesions, and 27 patients with aneuploid lesions. Data on cancer-specific mortality and treatment were obtained from the Cancer Registry of Norway, Statistics Norway, and chart reviews.

RESULTS

Primary oral carcinoma developed in 47 of the 150 patients with leukoplakia (31 percent)--5 with diploid, 16 with tetraploid, and 26 with aneuploid leukoplakia--during a mean follow-up of 80 months (range, 4 to 237). The margin status of the initial leukoplakia resection had no relation to the development of oral cancer (P=0.95). Twenty-six of the 47 patients in whom cancer developed (4 with prior tetraploid and 22 with prior aneuploid lesions) had recurrences (55 percent); the recurrences were more frequently multiple and distant (within the oral cavity) among patients with aneuploid lesions than among those with tetraploid or diploid lesions. All 47 patients underwent a standard regimen of surgery and radiation, followed by chemotherapy in the 26 with recurrent cancer. Only patients with aneuploid leukoplakia died of oral cancer; the five-year rate of death from cancer was 72 percent. Aneuploidy-related first carcinomas were diagnosed at a more advanced stage than were carcinomas originating from diploid or tetraploid leukoplakia (P=0.03) and were more likely to be lethal regardless of the stage.

CONCLUSIONS

Complete resection of aneuploid leukoplakia does not reduce the high risk of aggressive carcinoma and death from oral cancer.

Incidence and survival of squamous cell carcinoma of the tongue in Scandinavia, with special reference to young adults

In several countries, increased incidence of squamous cell carcinoma (SCC) of the tongue in young adults has been suspected during the last decades. Some reports indicate a lower survival rate for young patients compared to older patients. In other reports, there has not been any considerable difference in survival when comparing young adults to older patients, whereas some authors have shown better survival for young adults. This disease is rare in young adults, and early reports were based on comparable small numbers and selected patients. Our aim was first to perform a population-based study to determine if an increased incidence in SCC of the tongue could be verified in a larger population comprising the Scandinavian countries Denmark, Finland, Sweden and Norway. A second aim was to determine survival rates for young adults compared to older patients. The material was based on the annual cancer incidence and survival reports from the Scandinavian cancer registries. The study period was 1960-1994. During that period, 5,024 SCCs of the tongue were reported. Of these, 276 (5.5%) were young adults (20-39 years). The incidence increased at all ages except for women 65-79 years old. The increase was most pronounced in young adults: 0.06-0.32 for men and 0.03-0.19 for women, counted by 100,000 person-years. Relative survival was significantly better for young adults compared to older patients.

Haematological malignancies in a general population, based on information collected from a population study, hospital records, and the Cancer Registry of Norway: the Tromsø Study

OBJECTIVES

To investigate the prevalence and incidence of haematological malignancies, and to compare the rates found with those reported from the Cancer Registry of Norway.

METHODS

Three sources of information were used: (1) automated blood cell counts from 27 145 persons older than 24 yr (72% of those invited), participating in a population study (the Tromsø Study 1994-95); (2) patient medical records at the University Hospital of Tromsø during 1991-96; (3) the Cancer Registry of Norway.

RESULTS

(1) In the population study, 13 new cases of haematological malignancies were diagnosed. For five of these the early detection was probably beneficial. (2) From the hospital records another 59 participants and 36 non-participants to the population study were found to have haematological malignancies. (3) Additionally, six cases were identified from the Cancer Registry. Totally, we thus identified 114 period prevalent cases, of which 86% had been reported to the Cancer Registry. Age-adjusted period prevalence of haematological malignancies was 4.7 per thousand in men and 2.9 per thousand in women. The prevalence increased with age. There were 84 cases with leukaemia, lymphoma, or multiple myeloma diagnosed at any time and still alive at 31 December 1996 (point prevalence 2.2 per thousand). Our estimated incidence of haematological malignancies did not differ significantly from that reported from the Cancer Registry.

CONCLUSION

We found approximately the same rates of haematological malignancies as the Cancer Registry, although an underreporting of 14% to the Cancer Registry was detected. The point prevalence of leukaemia, lymphoma, and multiple myeloma was 2.2%.

Human papillomavirus infection as a risk factor for squamous-cell carcinoma of the head and neck

BACKGROUND

Oncogenic human papillomaviruses (HPVs), especially HPV type 16 (HPV-16), cause anogenital epithelial cancers and are suspected of causing epithelial cancers of the head and neck.

METHODS

To examine the relation between head and neck cancers and HPVs, we performed a nested case-control study within a joint Nordic cohort in which serum samples were collected from almost 900,000 subjects. Samples collected at enrollment from 292 persons in whom squamous-cell carcinoma of the head and neck developed, on average, 9.4 years after enrollment and from 1568 matched controls were analyzed for antibodies against HPV-16, HPV-18, HPV-33, and HPV-73 and for cotinine levels as a marker of smoking habits. Polymerase-chain-reaction (PCR) analyses for HPV DNA were performed in tumor tissue from 160 of the study patients with cancer.

RESULTS

After adjustment for cotinine levels, the odds ratio for squamous-cell carcinoma of the head and neck in subjects who were seropositive for HPV-16 was 2.2 (95 percent confidence interval, 1.4 to 3.4). No increased risk was observed for other HPV types. Fifty percent of oropharyngeal and 14 percent of tongue cancers contained HPV-16 DNA, according to PCR analysis.

CONCLUSIONS

HPV-16 infection may be a risk factor for squamous-cell carcinoma of the head and neck.

Familial risk in head and neck squamous cell carcinoma diagnosed before the age of 45: a population-based study

This population-based study analyses familial risk as a factor in the development of head and neck squamous cell carcinoma before the age of 45. Two different designs were used: (1) estimation of standardised incidence ratios (SIRs) for cancer among first-degree relatives of 127 young head and neck cancer probands; and (2) estimation of odds ratios (ORs) for developing head and neck cancer associated with cancer in a first-degree relative. SIRs of cancer of the respiratory and upper digestive tract (lungs, oesophagus, and smoking-related head and neck sites [RUDT]) for first-degree relatives were 4.3 (95% confidence intervals or 95% CI of 1.6-9.5) for female patients, 1.0 (95% CI = 0.3-2.6) for male patients and 1.9 (95% CI = 0.9-3.5) for both sexes combined. ORs for head and neck cancer before the age of 45, in association with cancer of RUDT in a first-degree relative were 5.0 (95% CI = 1.4-17.3) for women, 1.1 (95% CI = 0.3-3.3) for men, and 2.0 (95% CI = 0.9-4.4) for both sexes combined. Hence, when analysing both sexes combined, our familial risk estimates for head and neck cancer showed non-significant increases. An explanation for the unexpected sex asymmetry in familial risk could be an interaction between inherent cancer susceptibility and a female biological characteristic. Alternatively, it could be artefacts caused by differences in familial smoking habits.

Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens

BACKGROUND

Nonmelanoma skin cancer occurs frequently in organ transplant recipients, but the relative importance of different immunosuppressive therapy regimens is unclear.

OBJECTIVE

We studied the risk of skin cancer in the complete, single-center Norwegian cohort of kidney and heart transplant recipients (n = 2561).

METHODS

We determined cancer risk estimation by means of standardized incidence ratios and multivariate Cox regression.

RESULTS

Transplant recipients had an increased risk of cutaneous squamous cell carcinoma (SCC) (65-fold), malignant melanoma (3-fold), and Kaposi's sarcoma (84-fold), and of lip SCC (20-fold), compared with the general population. After adjustment for age, kidney transplant recipients receiving cyclosporine, azathioprine, and prednisolone had a significantly (2.8 times) higher risk of cutaneous SCC relative to those receiving azathioprine and prednisolone. After adjustment for age and type of immunosuppressive regimen, heart transplant recipients had a significantly (2.9 times) higher risk than kidney transplant recipients.

CONCLUSION

The risk of cutaneous SCC, malignant melanoma, Kaposi's sarcoma, and lip SCC is increased in kidney and heart transplant recipients. The risk of posttransplant cutaneous SCC is related to the degree of immunosuppression caused by long-term immunosuppressive therapy.