Thursday, August 11, 2016

Brain Tumor Rates Are Rising in the US: The Role of Cell Phone & Cordless Phone Use

For additional evidence that cellphone and cordless phone use increase
brain tumor risk and that brain tumor incidence has been increasing in the U.S.


Hardell and Carlberg (2015) reported that brain tumor rates have been increasing in Sweden based upon the Swedish National Inpatient Registry data.

What about brain tumor rates in the United States?

Using national tumor registry data, a recent study found that the overall incidence of meningioma, the most common non-malignant brain tumorhas significantly increased in the United States in recent years (Dolecek et al., 2015). The age-adjusted incidence rate for meningioma significantly increased from about 6.3 per 100,000 in 2004 to about 7.8 per 100,000 in 2009. Brain tumor incidence increased for all age groups except youth (0-19 years of age).

The incidence of glioma, the most common malignant brain tumor, has also been increasing in recent years in the United States, although not across-the-board. The National Cancer Institute reported that glioma incidence in the frontal lobe increased among young adults 20-29 years of age (Inskip et al., 2010). The incidence of glioblastoma multiforme (GBM), a highly cancerous glioma, increased in the frontal and temporal lobes, and in the cerebellum among adults of all ages in the U.S. (Zada et al., 2012). 

Risk of meningioma from cell phone and cordless phone use

A study by Carlberg and Hardell (2015) adds to the growing body of evidence that heavy use of wireless phones (i.e., cell phones and cordless phones) is associated with increased risk of meningioma in Sweden. Heavy cordless phone users (defined as more than 1,436 hours of lifetime use) had a 1.7-fold greater risk of meningioma (OR = 1.7; 95% CI = 1.3-2.2). The heaviest cordless phone users (defined as more than 3,358 hours of lifetime use) had a two-fold greater risk of meningioma (OR = 2.0; 95% CI = 1.4 - 2.8). The heaviest cell phone users had a 1.5-fold greater risk of meningioma (OR = 1.5, 95% CI = 0.99 - 2.1). 

Two earlier case-control studies conducted in other nations have found significant evidence of increased risk for meningioma among heavy cell phone users:

(1) In France, Coureau et al. (2014) found a two and a half-fold greater risk of meningioma for heavy cell phone users (defined as 896 or more hours of lifetime use) (OR = 2.57; 95% CI = 1.02 to 6.44). 

(2) In Australia, Canada, France, Israel and New Zealand, Cardis et al. (2011) found a two-fold greater risk of meningioma for heavy cell phone users (defined as 3,124 or more hours of lifetime use) (OR = 2.01; 95% CI = 1.03 to 2.93). 

The two prior studies did not assess cordless phone use so it's likely they underestimate the meningioma risk from cell phone use.

Thus, we now have three independent, case-control studies which find that wireless phone use is a risk factor for meningioma.

Risk of glioma from cell phone and cordless phone use

Three independent, case-control studies have found that long-term use of cell phones increases risk for glioma (Interphone Study Group, 2010Hardell et al, 2013Coureau et al, 2014). The only research to examine cordless phone use also found increased glioma risk with long-term use (Hardell et al, 2013). These studies include data from 13 nations: Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden and the UK. After ten years of wireless phone use (i.e., cell phone plus cordless phone use), the risk of glioma doubles and after 25 years, the risk triples (Hardell et al, 2013).

Although the U.S. does not conduct research on wireless phone use and tumor risk in humans and does not participate in any of the international studies, there is no reason to believe that Americans are immune to these potential effects of wireless phone use.


In sum, the peer-reviewed research on brain tumor risk and wireless phone use strongly suggests that we should exercise precaution and keep cell phones and cordless phones away from our heads. Moreover, the research calls into question the adequacy of national standards and international guidelines that limit our exposure to radiation from wireless phones.


Recent Research Studies & Reports

Comparative Study of Brain & Central Nervous System Tumor Incidence between the U.S. and Taiwan

Chien LN, Gittleman H, Ostrom QT, Hung KS, Sloan AE, Hsieh YC, Kruchko C, Rogers LR, Wang YF, Chiou HY, Barnholtz-Sloan JS. Comparative Brain and Central Nervous System Tumor Incidence and Survival between the United States and Taiwan Based on Population-Based Registry. Front Public Health. 2016 Jul 21;4:151.

Abstract

PURPOSE: Reasons for worldwide variability in the burden of primary malignant brain and central nervous system (CNS) tumors remain unclear. This study compares the incidence and survival of malignant brain and CNS tumors by selected histologic types between the United States (US) and Taiwan.

METHODS: Data from 2002 to 2010 were selected from two population-based cancer registries for primary malignant brain and CNS tumors: theCentral Brain Tumor Registry of the United States and the Taiwan Cancer Registry. Two registries had similar process of collecting patients with malignant brain tumor, and the quality of two registries was comparative. The age-adjusted incidence rate (IR), IR ratio, and survival by histological types, age, and gender were used to study regional differences.

RESULTS: The overall age-adjusted IRs were 5.91 per 100,000 in the US and 2.68 per 100,000 in Taiwan. The most common histologic type for both countries was glioblastoma (GBM) with a 12.9% higher proportion in the US than in Taiwan. GBM had the lowest survival rate of any histology in both countries (US 1-year survival rate = 37.5%; Taiwan 1-year survival rate = 50.3%). The second largest group was astrocytoma, excluding GBM and anaplastic astrocytoma, with the distribution being slightly higher in Taiwan than in the US.

CONCLUSION: Our findings revealed differences by histological type and grade of primary malignant brain and CNS tumors between two sites.

Open Access Paper: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4954825/


Excerpts

Between 2002 and 2010, there were 183,740 newly diagnosed cases of malignant brain and CNS tumors in the US and 5,855 in Taiwan.

The most common histologic group for both countries was GBM; 47.8% of all tumors in the US and 34.9% of all tumors in Taiwan (Figure 3).

The IR of GBM was 2.9 times in the US (2.48 per 100,000) as compared with Taiwan (0.85 per 100,000). The second highest histologic group was astrocytoma (excluding GBM and AA) in both the US (0.95 per 100,000) and Taiwan (0.44 per 100,000).

In the US, the IRs by primary site were highest for tumors located in the frontal lobe (1.34 per 100,000), followed by tumors located in all other sites within the brain, temporal lobe, parietal lobe, and the other parts of brain and CNS. In Taiwan, the IRs were highest for tumors located in all other parts of the brain (0.70 per 100,000), followed by tumors located in the frontal lobe, temporal lobe, and cerebrum.

In this study, the lower age-adjusted IRs of malignant brain and CNS tumors in Taiwan was less likely due to differences in imaging diagnostic techniques as the standards for imaging for brain and CNS tumors was the same in both countries.


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Adolescent and Young Adult Primary Brain and Central Nervous System Tumors Diagnosed in the United States in 2008-2012

Ostrom QT, Gittleman H, de Blank PM, Finlay JL, Gurney JG, McKean-Cowdin R, Stearns DS, Wolff JE, Liu M, Wolinsky Y, Kruchko C, Barnholtz-Sloan JS. American Brain Tumor Association Adolescent and Young Adult Primary Brain and Central Nervous System Tumors Diagnosed in the United States in 2008-2012. Neuro Oncol. 2016 Jan;18 Suppl 1:i1-i50. http://www.ncbi.nlm.nih.gov/pubmed/26705298


The incidence of the most common non-malignant tumors (e.g., meningioma, pituitary) has increased in recent years among adolescents and young adults (AYA) in the U.S; however, some of this increase may be due to better reporting over time.

“Collection of data on non-malignant brain and CNS tumors began in 2004, after the passage of the Benign Brain Tumor Act in 2002. Previous analyses have suggested that increased incidence in the time period between 2004 and 2006 may be the result of the initiation of this collection rather than a ‘true’ increase in incidence.”
  • "Incidence of oligodendroglioma (APC = 22.9) and anaplastic oligodendroglioma (APC = 24.1) in AYA has significantly decreased from 2004-2012. 
  • Incidence of tumors of the meninges in AYA has significantly increased from 2004-2012 (APC = 2.5), which is largely driven by the increase of meningioma incidence during that time (APC = 2.6).  
  • Incidence of lymphomas and hematopoietic neoplasms has significantly decreased from 2004-2012 (APC = 22.8) in AYA. 
  • Incidence of tumors of the sellar region in AYA has significantly increased from 2004-2008 (APC = 8.5), which is largely driven by the increase of tumors of the pituitary incidence from 2004-2009 (APC = 7.6).
  • Incidence of unclassified tumors in AYA has significantly increased from 2004-2012 (APC = 5.5), which is largely driven by the increase of hemangioma incidence from 2004-2010 (APC = 18.8)."
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Malignant Brain Tumors Most Common Cause of Cancer Deaths in Adolescents & Young Adults

Press Release, American Brain Tumor Association, Feb 24, 2016

A new report published in the journal Neuro-Oncology and funded by the American Brain Tumor Association (ABTA) finds that malignant brain tumors are the most common cause of cancer-related deaths in adolescents and young adults aged 15-39 and the most common cancer occurring among 15-19 year olds.

The 50-page report, which utilized data from the Central Brain Tumor Registry of the United States (CBTRUS) from 2008-2012, is the first in-depth statistical analysis of brain and central nervous system (CNS) tumors in adolescents and young adults (AYA). Statistics are provided on tumor type, tumor location and age group (15-19, 20-24, 25-29, 30-34 and 35-39) for both malignant and non-malignant brain and CNS tumors.

"When analyzing data in 5-year age increments, researchers discovered that the adolescent and young adult population is not one group but rather several distinct groups that are impacted by very different tumor types as they move into adulthood," said Elizabeth Wilson, president and CEO of the American Brain Tumor Association.

"For these individuals -- who are finishing school, pursuing their careers and starting and raising young families -- a brain tumor diagnosis is especially cruel and disruptive," added Wilson. "This report enables us for the first time to zero-in on the types of tumors occurring at key intervals over a 25-year time span to help guide critical research investments and strategies for living with a brain tumor that reflect the patient's unique needs."

Although brain and CNS tumors are the most common type of cancer among people aged 15-19, the report shows how other cancers become more common with age. By ages 34-39 years, brain and CNS tumors are the third most common cancer after breast and thyroid cancer.

"What's interesting is the wide variability in the types of brain tumors diagnosed within this age group which paints a much different picture than what we see in adults or in pediatric patients," explained the study's senior author Jill Barnholtz-Sloan, Ph.D., associate professor, Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine and Scientific Principal Investigator for CBTRUS.

"For example, the most common tumor types observed in adults are meningiomas and glioblastomas, but there is much more diversity in the common tumor types observed in the adolescent and young adult population. You also clearly see a transition from predominantly non-malignant and low-grade tumors to predominantly high-grade tumors with increasing age," Barnholtz-Sloan said.

There are nearly 700,000 people in the U.S. living with brain and CNS tumors and approximately 15 percent of these tumors occurred in the AYA population during the 2008-2012 time frame analyzed in this report. Approximately 10,617 brain and CNS tumors are diagnosed among adolescents and young adults each year and are the cause of approximately 434 deaths annually.

"The American Brain Tumor Association's recognition of this understudied population, and their commitment to data and information sharing should be applauded," added Barnholtz-Sloan. "There are clearly unique characteristics of the 15-39 age group that we need to more comprehensively understand and the information in the ABTA report starts that important dialogue."

The full report is available at http://www.abta.org/about-us/news/brain-tumor-statistics/.

To learn more or access additional statistics, go to http://www.abta.org.

http://bit.ly/1OvDHYy

Brain Tumor Statistics

Brain tumors are the:
  • most common cancer among those age 0-19 (leukemia is the second).
  • second leading cause of cancer-related deaths in children (males and females) under age 20 (leukemia is the first).
  • Nearly 78,000 new cases of primary brain tumors are expected to be diagnosed this year. This figure includes nearly 25,000 primary malignant and 53,000 non-malignant brain tumors.
  • It is estimated that more than 4,600 children between the ages of 0-19 will be diagnosed with a primary brain tumor this year.
  • There are nearly 700,000 people in the U.S. living with a primary brain and central nervous system tumor.
  • This year, nearly 17,000 people will lose their battle with a primary malignant and central nervous system brain tumor.
  • There are more than 100 histologically distinct types of primary brain and central nervous system tumors.
  • Survival after diagnosis with a primary brain tumor varies significantly by age, histology, molecular markers and tumor behavior.
  • The median age at diagnosis for all primary brain tumors is 59 years.
Tumor-Specific Statistics:
  • Meningiomas represent 36.4% of all primary brain tumors, making them the most common primary brain tumor.  There will be an estimated 24,880 new cases in 2016.
  • Gliomas, a broad term which includes all tumors arising from the gluey or supportive tissue of the brain, represent 27% of all brain tumors and 80% of all malignant tumors.
  • Glioblastomas represent 15.1% of all primary brain tumors, and 55.1% of all gliomas.
  • Glioblastoma has the highest number of cases of all malignant tumors, with an estimated 12,120 new cases predicted in 2016.
  • Astrocytomas, including glioblastoma, represent approximately 75% of all gliomas.
  • Nerve sheath tumors (such as acoustic neuromas) represent about 8% of all primary brain tumors.
  • Pituitary tumors represent 15.5% of all primary brain tumors. There will be an estimated 11,700 new cases of pituitary tumors in 2016.
  • Lymphomas represent 2% of all primary brain tumors.
  • Oligodendrogliomas represent nearly 2% of all primary brain tumors.
  • Medulloblastomas/embryonal/primitive tumors represent 1% of all primary brain tumors.
  • The majority of primary tumors (36.4%) are located within the meninges.
http://www.abta.org/about-us/news/brain-tumor-statistics/

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Central Brain Tumor Registry of the United States: 2015 Fact Sheet

One in 161 Americans (0.62%) will be diagnosed with brain or other central nervous system (CNS) cancer during their lifetime according to the Central Brain Tumor Registry of the United States. 

The risk is greater for males (1 in 144 or 0.69%) than females (1 in 182 or 0.55%): About three out of four people (74%) who develop brain or CNS cancer will die from this disease.

The risk of being diagnosed with a non-malignant (i.e., non-cancerous) brain or CNS tumor is about twice as great (14.75 vs. 7.23 per 100,000 per year).


Excerpts
The incidence rate of all primary malignant and non-malignant brain and CNS tumors is 21.97 cases per 100,000 for a total count of 356,858 incident tumors; (7.23 per 100,000 for malignant tumors for a total count of 117,023 incident tumors and 14.75 per 100,000 for non-malignant tumors for a total count of 239,835 incident tumors). The rate is higher in females (23.95 per 100,000 for a total count of 206,565 incident tumors) than in males (19.82 per 100,000 for a total count of 150,271 incident tumors).

An estimated 77,670 new cases of primary malignant and non-malignant brain and CNS tumors are expected to be diagnosed in the United States in 2016. This includes an estimated 24,790 primary malignant and 52,880 non-malignant that are expected to be diagnosed in the US in 2016.

Pediatric Incidence (Ages 0-14 Years)
The incidence rate of childhood primary malignant and non-malignant brain and CNS tumors in the US is 5.37 cases per 100,000 for a total count of 16,366 incident tumors. The rate is higher in males (5.61 per 100,000) than females (5.11 per 100,000).

An estimated 4,630 new cases of childhood primary malignant and non-malignant brain and CNS tumors are expected to be diagnosed in the US in 2016.
Pediatric & Adolescent Incidence (Ages 0-19 Years)
The incidence rate of childhood and adolescent primary malignant and non-malignant brain and CNS tumors in the US is 5.57 per 100,000 for a total count of 23,113 incident tumors. The rate is higher in males (5.60 per 100,000) than females (5.54 per 100,000).

An estimated 4,620 new cases of primary malignant and non-malignant brain and CNS tumors are expected to be diagnosed in the US in 2015.
Adolescent & Young Adult (AYA) Incidence (Ages 15-39 Years)
The incidence rate of AYA primary malignant and non-malignant brain and CNS tumors is 10.47 cases per 100,000 for a total count of 53,083 incident tumors.1 The rate is higher for non-malignant tumors (6.17 per 100,000) than malignant tumors (3.26 per 100,000).

An estimated 10,390 new cases of AYA primary malignant and non-malignant brain and CNS tumors are expected to be diagnosed in the US in 2016.
Mortality
The average annual mortality rate in the US between 2008 and 2012 was 4.31 per 100,000 with 71,831 deaths attributed to primary malignant brain and CNS tumors.

An estimated 16,616 deaths will be attributed to primary malignant brain and CNS tumors in the US in 2016.
Lifetime Risk
From birth, a person in the US has a 0.62% chance of ever being diagnosed with a primary malignant brain/CNS tumor (excluding lymphomas, leukemias, tumors of pituitary and pineal glands, and olfactory tumors of the nasal cavity) and a 0.46% chance of dying from the primary malignant brain/CNS tumor.

For males in the US, the risk of developing a primary malignant brain/CNS tumor is 0.69%, and the risk of dying from a primary malignant brain/CNS tumor (excluding lymphomas, leukemias, tumors of pituitary and pineal glands, and olfactory tumors of the nasal cavity) is 0.51%.

For females in the US, the risk of developing a primary malignant brain/CNS tumor is 0.55%, and the risk of dying from a primary malignant brain/CNS tumor (excluding lymphomas, leukemias, tumors of pituitary and pineal glands, and olfactory tumors of the nasal cavity) is 0.41%.
Prevalence
The prevalence rate for all primary brain and CNS tumors was estimated to be 221.8 per 100,000 (61.9 per 100,000 for malignant; 177.3 per 100,000 for non-malignant) in 2010. It was estimated that more than 688,096 persons were living with a diagnosis of primary brain and central nervous system tumor in the United States in 2010 (malignant tumors: more than 138,054 persons; non-malignant tumors: more than 550,042 persons).

The prevalence rate for all pediatric (ages 0-19) primary brain and central nervous system tumors was estimated at 35.4 per 100,000 with more than 28,000 children estimated to be living with this diagnosis in the United States in 2004.

Note
Estimated numbers of incidence of malignant and non-malignant brain and CNS tumors and deaths due to these tumors were calculated for 2015 and 2016 using age-adjusted annual tumor incidence rates generated for 2000-2012 for non-malignant tumors by state, age, and histologic type.
http://bit.ly/cbtrus2015
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Brain Tumors in Children and Adolescents

According to a recent studythere has been a significant increase in the incidence of primary malignant brain and central nervous system (CNS) tumors in American children (0-14 years of age) between 2000-2010, with an annual percentage change (APC) of 0.6%. In adolescents (15-19 years old), there was a significant increase in the incidence of primary malignant brain and CNS tumors between 2000-2008, with an APC of 1.0%. Adolescents also experienced an increase in non-malignant brain and CNS tumors from 2004-2010, with an APC of 3.9%.

The four-nation CEFALO case-control study found a 36% increased risk of brain tumors among children and adolescents 7-19 years of age who used mobile phones at least once a week for six months. Since this risk estimate was not statistically significant (OR = 1.36; 95% CI = 0.92 to 2.02), the authors dismissed this overall finding. However, in a subsample of 556 youth for whom cell phone company records were available, there was a  significant association between the time since first mobile phone subscription and brain tumor risk. Children who used cellphones for 2.8 or more years were twice as likely to have a brain tumor than those who never regularly used cellphones (OR = 2.15, 95% CI = 1.07 to 4.29). 

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Trends in Incidence of Non-Malignant Head and Neck Tumors in the U.S.

The likelihood of developing a non-malignant brain tumor has increased in recent years in the U.S. According to newly-released data from the Centers for Disease Control and Prevention (CDC), the overall age-adjusted incidence (per 100,000 persons) of non-malignant brain tumors significantly increased from 2004 through 2012. The increase was observed among children 0-19 years of age (1.7 in 2004; 2.3 in 2012) and among adults 20 years and older (15.9 in 2004; 19.7 in 2012).

Almost 200 people per day in the U.S. were diagnosed with brain tumors in 2012 including 67,612 adults and 4,615 children. Among adults, 70% of these tumors were nonmalignant, and among children, 42% were nonmalignant.

The overall incidence of malignant tumors in the U.S. has been stable for children (3.4 in 2004; 3.3 in 2012) and has slightly decreased for adults (9.1 in 2004; 8.4 in 2012). However, lags in reporting to tumor registries are common in the U.S. so official statistics may underestimate the actual incidence of tumors for more recent years (see August 5, 2015 post below). 

A peer-reviewed study reported a significant Increase over time in the incidence of specific types of malignant brain tumors among adults in the U.S. (see May 7, 2015 post below).

The age-adjusted incidence of the most common non-malignant tumor, meningioma, significantly increased among adults from 2004 through 2012 (8.7 in 2004; 10.6 in 2012). 

A recent study reported a significant increase in meningioma incidence for the period 2004 through 2009 (Doleceket al., 2015). Several case-control studies have found a significant association between risk of meningioma and wireless phone use (see May 7, 2015 post below).

The age-adjusted incidence of pituitary gland tumors significantly increased among children (0.4 in 2004; 0.6 in 2012) and among adults (3.4 in 2004; 4.7 in 2012). 

A prospective study of 790,000 women in the United Kingdom reported that the risk pituitary gland tumors was more than twice as high among women who used a cell phone for less than five years as compared to never users (Bensonet al., 2013).

The web-based report, United States Cancer Statistics: 1999-2012 Incidence and Mortality Web-based Report (USCS) is available at www.cdc.gov/uscs. Although the report includes cancer cases diagnosed (incidence) from 1999 through 2012, brain tumor incidence data are available only since 2004. In 2012, cancer incidence information came from central cancer registries in 49 states, 6 metropolitan areas, and the District of Columbia, covering 99% of the U.S. population.

The Interactive Cancer Atlas (InCA), with exportable data, shows how rates differ by state and change over time. InCA is available at https://nccd.cdc.gov/DCPC_INCA/.

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Limitations of Cancer Registries

Cancer registries are developed to collect data on malignant tumors and often do not collect data on non-malignant (sometimes called benign) tumors. Since about half of primary brain tumors are non-malignant, these tumors are may not be monitored by public health surveillance systems (e.g., Canada).

The U.S has a Central Brain Tumor Registry (CBTRUS): "a resource for gathering and disseminating current epidemiologic data on all primary brain tumors, benign and malignant, for the purposes of accurately describing their incidence and survival patterns, evaluating diagnosis and treatment, facilitating etiologic studies, establishing awareness of the disease, and ultimately, for the prevention of all brain tumors." However, "CBTRUS makes no representations or warranties, and gives no other assurances or guarantees, express or implied, with respect to the accuracy or completeness of the data presented." 

There is a good reason for the disclaimer on the CBTRUS home page. Tumor registries are useful in monitoring disease incidence only to the extent that all procedures are well implemented. Registries are highly dependent upon reporting agencies (e.g., hospitals) to do an accurate and complete job in reporting tumors to the registry.

Registry data typically suffer from various problems: 
"Users must be aware of diverse issues that influence collection and interpretation of cancer registry data, such as multiple cancer diagnoses, duplicate reports, reporting delays, misclassification of race/ethnicity, and pitfalls in estimations of cancer incidence rates." (Izqierdo, JN, Schoenbach, VJ. The potential and limitations of data from population-based state cancer registries. Am J Public Health. 2000;90:695-698. URL: http://1.usa.gov/1IHO8FM)
Delays in reporting and late ascertainment are a reality and a known issue influencing registry completeness and, consequently, rate underestimations occur, especially for the most recent years.22 CBTRUS also recognizes that the problem may be even more likely to occur in the reporting of non-malignant brain and CNS tumors, where reporting often comes from non-hospital based sources and mandated collection is relatively recent (2004). Ostrom et al. (2014). URL: http://1.usa.gov/1PTmpaD).
For a discussion of the factors that undermine the data quality and completeness of cancer registry coverage of diagnosed tumors see Bray et al (2015)Coebergh et al (2015)and Siesling et al (2015)

The shortcomings of cancer registries are not just hypothetical. For example, Hardell and Carlberg (2015) recently reported that brain cancer rates have been increasing in Sweden based upon the Swedish National Inpatient Registry but not according to the Swedish Cancer Registry. Based upon their results they "postulate(d) that a large part of brain tumours of unknown type are never reported to the Cancer Register ... We conclude that the Swedish Cancer Register is not reliable ..."