February 24, 2012
Mr. David B. Clissold
Hyman, Phelps & McNamara, P.C.
700 13th Street NW
Washington, D.C. 20005
Re: Information Quality Request for Correction: The National Cancer Institute (NCI) Fact Sheet Cigar Smoking and Cancer
Dear Mr. Clissold:
Thank you for your “Information Quality Request for Correction” letter, dated June 1, 2011, that was submitted under the National Institutes of Health (NIH) Guidelines for Ensuring the Quality of Information Disseminated to the Public. This office received your letter on June 29, 2011. The following is NCI’s response to your request.
NCI is part of the NIH, which is one of 11 agencies that comprise the U.S. Department of Health and Human Services (HHS). NCI was established under the National Cancer Institute Act of 1937, and it is the Federal Government's principal agency for cancer research and training. NCI coordinates the National Cancer Program and conducts and supports research, training, health information dissemination, and other programs related to the causes, diagnosis, prevention, and treatment of cancer; rehabilitation from cancer; and the continuing care of cancer patients and their families.
NCI Fact Sheets
The NCI fact sheet collection (http://www.cancer.gov/cancertopics/factsheet) addresses a wide variety of cancer-related topics. These topics include risk factors, prevention, detection/diagnosis, treatment, and coping/support. NCI’s Office of Communications and Education regularly reviews and revises all of the fact sheets in the collection based on the most current cancer research findings. Similar to all other NCI information products disseminated to the public, NCI fact sheets undergo rigorous scientific review by relevant experts to ensure their factual accuracy. The Cigar Smoking and Cancer fact sheet was last reviewed and updated on October 27, 2010.
NCI fact sheets are intended for a broad, general audience. The information is presented concisely and in “plain language.” Therefore, the text cannot provide detailed explanations of highly complex scientific issues. In addition, although references are frequently provided to give readers sources of additional information, the fact sheets are not intended to provide large or comprehensive lists of scientific citations on the covered topics.
In response to your request, we carefully reviewed the scientific literature on the subject of cigar smoking and cancer. We appreciated the opportunity to ensure that the content of our fact sheet on this topic is as accurate and as up-to-date as possible.
Scientific Evidence on Cigars
As stated in the Cigar Smoking and Cancer fact sheet, cigars comprise a diverse class of tobacco products. They vary in shape, size, and the type of tobacco used and contain from 1 to 20 grams of tobacco. Large cigars can measure more than 7 inches in length and may contain the same amount of tobacco as an entire pack of cigarettes. At the other end of the spectrum, little cigars are typically the same size and shape as cigarettes and are often sold in packs of twenty, like cigarettes. Some little cigars have a filter that may lead smokers to use them like a cigarette, such as by inhaling the smoke. Because of differences in size and other characteristics, cigars also vary substantially in the amount of nicotine and harmful constituents they contain and deliver to the smoker. This diversity makes it difficult to draw broad generalizations about the degree of exposure to smoke toxicants and the harms associated with cigar smoking relative to other tobacco products, or to draw risk-based comparisons between users of different products. Moreover, cigar smokers exhibit a variety of smoking patterns and behaviors that influence the exposures they receive.
Previous reports and scientific studies have provided a substantial body of evidence on the health effects of cigar smoking:
The NCI Monograph Cigars: Health Effects and Trends (Smoking and Tobacco Control Monograph 9, 1998) reviewed the data available at the time on the health effects of cigar smoking. Key overall conclusions in that volume included the following:
- “Cigar smoking can cause oral, esophageal, laryngeal and lung cancers. Regular cigar smokers who inhale, particularly those who smoke several cigars per day, have an increased risk of coronary heart disease and chronic obstructive pulmonary disease.” (p. 19)
- “Regular cigar smokers have risks of oral and esophageal cancers similar to those of cigarette smokers, but they have lower risks of lung and laryngeal cancer, coronary heart disease and chronic obstructive pulmonary disease.” (p. 19)
The International Agency for Research on Cancer (IARC) Monograph Tobacco Smoke and Involuntary Smoking (Volume 83, 2002) provided a comprehensive review of the evidence available at the time on cigar smoking and cancer.1 IARC’s summary conclusion stated:
“Cigar and/or pipe smoking is strongly related to cancers of the oral cavity, oropharynx, hypopharynx, larynx and oesophagus, the magnitude of risk being similar to that from cigarette smoking. These risks increase with the amount of cigar and/or pipe smoking and with the combination of alcohol and tobacco consumption. Cigar and/or pipe smoking is causally associated with cancer of the lung and there is evidence that cigar and/or pipe smoking are also causally associated with cancers of the pancreas, stomach and urinary bladder.”
The IARC Monograph Smokeless Tobacco and Some Tobacco-Specific N-Nitrosamines (TSNAs) (Volume 89, 2007) described studies of the carcinogenic content of cigars.2 In particular, the report stated that, under several different laboratory smoking regimens tested, cigars yielded higher levels of TSNAs than cigarettes. Specifically:
“Under standard ISO/FTC machine-smoking conditions, the levels of NNK in the mainstream smoke of premium cigars were 17 times higher than those of medium-yield cigarettes; NNN levels were 22.4 times higher (931 versus 41.5 ng/unit) (Rickert & Kaiserman, 1999). Djordjevic et al. (1997) also explored the levels of TSNA in the mainstream smoke of small cigars using methods that mimic human smoking patterns and compared the data with those obtained by standard machine-smoking methods. Under human smoking conditions, the emissions of NNK, NNN and NAT were 1.7-fold, 2.1-fold and 1.8-fold higher, respectively, than those obtained under standard protocols.” (p. 443)
The 2010 U.S. Surgeon General’s report How Tobacco Smoke Causes Disease3 also summarizes scientific evidence on the effects of cigar smoking. This report states:
“Compared with persons who smoke cigarettes, smokers who exclusively smoke pipes or cigars have lower risk for many smoking-related diseases (NCI 1998). Smoke from pipes and cigars contains the same toxic substances as cigarette smoke, but those who use a pipe or cigar usually smoke at lower intensity; observation indicates that they tend not to inhale the smoke, thus reducing their exposure to its toxic substances (USDHEW 1979; NCI 1998; Shanks et al. 1998). Most current cigar users are young males who often smoke less than one cigar daily (NCI 1998); no data on risk for this population are available. For older adults who regularly use cigars, particularly those who smoke more than one cigar per day or inhale the smoke, risk of CHD is modestly higher than that for nonsmokers (NCI 1998; Iribarren et al. 1999; Jacobs et al. 1999b; Baker et al. 2000).” (p. 632)
Additional Research Findings
A number of recent research studies have added to this body of evidence and raised further concerns about the public health impact of cigar smoking. Recent findings, not cited in the Cigar Smoking and Cancer fact sheet, further strengthen the statements and conclusions made in the fact sheet.
Consumption and Use
- Overall annual cigar consumption in the United States continues to increase and more than doubled between 1990 and 2007.4
- Data from the National Youth Tobacco Survey and state youth tobacco surveys from 2001-2002 (representative of middle school and high school students in 50 states and the District of Columbia) showed that cigar smoking was the second most prevalent form of tobacco use after cigarettes.5
- Past-month cigar use is highest among adolescents and young adults compared with older age groups.4
- Several surveys and focus group studies show that some youth and young adults prefer cigars to cigarettes, identify with particular brands or flavors, and have erroneous beliefs about the health hazards of cigar smoking.
- A recent analysis by McCormack et al., using data from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study, reported cancer risks among cigar and pipe smokers (n = 102,395). Their results confirm previous findings that cigar smoking causes lung, upper aerodigestive tract, and bladder cancers. Risk was raised with increasing duration of smoking, greater intensity of smoking, and with the inhalation of smoke. The researchers concluded that the differences in cancer risk observed between cigar smokers and cigarette smokers may be explained by differences in smoking inhalation and intensity. However, they cautioned that cigarette smokers who switch to smoking cigars may not lower their risk if they do not change their smoking intensity or inhalation patterns and conclude that “cigar and pipe smoking is not a safe alternative to cigarette smoking.”9
- An international case-control study of pancreatic cancer involving approximately 6,000 cases and 11,000 controls provided further confirmation of an association between cigar smoking and pancreatic cancer. The odds ratio observed in the study for cigar-only smokers, compared with never smokers, was similar to that observed for cigarette-only smokers (OR 1.6 for cigar-only and 1.5 for cigarette-only).10
- A study of 3,500 U.S. adults without clinical cardiovascular disease at enrollment found that current cigar smokers exhibited higher urinary cotinine levels, decreased lung function, and increased odds of airflow obstruction, even in participants who had never smoked cigarettes.11
Nicotine Content and Delivery
- A study by Henningfield et al. examined characteristics related to nicotine delivery for 17 cigar brands, ranging from small cigars to large premium cigar brands. There was considerable variation in total nicotine content, which ranged from 5.9 to 335.2 mg per cigar. The pH values of cigar tobacco and cigar smoke also varied substantially, which would affect nicotine absorption. The researchers found that all of the cigars studied were capable of delivering sufficient amounts of nicotine to maintain nicotine dependence.12
Responses to Specific Comments in the “Information Quality Request for Correction” Letter
Requestor comment 2a): “Thus, although the FactSheet notes a difference in inhalation between cigars and cigarettes, the important health consequences of this difference are never mentioned for context. Thus, the FactSheet is incomplete and biased in violation of the HHS Guidelines.”
NCI Response: Differences in inhalation practices may provide a partial explanation for differences in observed disease outcomes among regular cigarette smokers and regular cigar smokers. However, disease risk among cigar smokers depends on the manner in which they smoke, smoking duration and intensity, and concurrent use of other tobacco products. In fact, NCI’s Monograph Cigars: Health Effects and Trends cautions that observations of smoking behavior from studies of adult cigar users may not apply to those who begin cigar use as adolescents or to cigarette smokers who switch to cigar use. Thus, it is inaccurate to conclude that cigars are inherently less harmful than cigarettes.
Requestor comment 2b): “The FactSheet does not mention this data demonstrating that occasional cigar smokers (comprising as much as 75% of the population of cigar smokers) are at no greater risk for disease than non-smokers. According to the FactSheet, cessation is the only alternative that reduces risk. Thus, the FactSheet lacks appropriate context and is both incomplete and biased within the meaning of ‘objectivity’ in the HHS Guidelines.”
NCI Response: The requestor’s statement misinterprets the epidemiologic data on occasional cigar use. Risks among occasional cigar smokers are difficult to measure because of variability in patterns of use and in product characteristics. The lack of robust epidemiologic data characterizing the risks of occasional cigar use does not mean that there is no risk. NCI’s Monograph Cigars: Health Effects and Trends states, “The claim has been made that cigar smokers who smoke few cigars or do not inhale have no increased risk of disease. …A more accurate statement would be that the risks experienced by cigar smokers are proportionate to their exposure to tobacco smoke.” (p. 8) One of the major conclusions of the 2010 Report of the Surgeon General, How Tobacco Smoke Causes Disease, states that “[t]he evidence on the mechanisms by which smoking causes disease indicates that there is no risk-free level of exposure to tobacco smoke.” (p. 9) This conclusion applies to all smoked tobacco products, including cigars.
Requestor comment 2c): “Monograph 9 says that even if cigars may cause addiction, it is something lower than what is seen for cigarettes. ‘The pattern of cigar use in the population (infrequent use, low number of cigars smoked per day, and lower rates of inhalation compared to cigarette smokers), suggest that cigar use which begins in adulthood may be less likely to produce dependence than cigarette smoking’ (Monograph 9 at 191). In contrast, the FactSheet states definitively that cigars are addictive. Thus, the FactSheet is not an objective summary of the available data regarding addiction. Moreover, the FactSheet does not reference any source for such a definitive statement, which in itself is a violation of the HHS Guidelines.”
NCI Response: The requestor mischaracterizes the statements about addiction in NCI’s Monograph 9. The Monograph concludes that “There is sufficient nicotine absorption among regular heavy cigar smokers to expect that nicotine dependence might develop, but studies to document the frequency or intensity of nicotine dependence have not been published.” (p. 191) Additionally, the Monograph explains that cigars can deliver nicotine to the smoker in concentrations comparable to those delivered by cigarettes and smokeless tobacco. It is accurate to conclude that cigars are addictive while not all cigar users experience tobacco dependence; the likelihood of addiction will vary depending on the user’s behavior. Additionally, Monograph 9 also warns that the pattern of cigar use observed in the adult population may not apply to the potential for addiction with increasing adolescent cigar use.
Requestor comment 3d): “In fact, the FactSheet itself states: ‘Although cigar smokers have lower rates of lung cancer, coronary heart disease, and lung disease than cigarette smokers, they have higher rates of these diseases than those who do not smoke cigars.’ If cigar smokers have lower rates of disease than cigarette smokers, then cigars are less hazardous than cigarettes. Moreover, as noted above, Monograph 9 clearly concludes that people who smoke 1-2 cigars per day do not have higher rates of many diseases even when compared to nonsmokers. …Moreover, as noted above ‘as many as three-quarters of cigar smokers smoke only occasionally’ (Monograph 9 at iii). By not mentioning this data, the FactSheet implies that all cigar smokers are at increased risk, making the FactSheet both incomplete and biased within the meaning of ‘objectivity’ in the HHS Guidelines.”
NCI Response: Disease risk among cigar smokers depends on the characteristics of the product used, the manner in which the product is smoked, smoking duration and intensity, and concurrent use of other tobacco products. Thus, it is inaccurate to conclude that cigars are inherently less harmful than cigarettes, as the risks to the user depend on the user’s behaviors. Moreover, as noted in our previous response, several studies indicate that cigar consumption is increasing among youth, whose patterns of use may be very different from adult cigar smokers.
Requestor comment 2e): “Moreover, Monograph 9 recognizes that these health effects are not experienced by the occasional cigar smoker (1-2 cigars per day). Monograph 9 states that ‘regular cigar smoking causes cancer of the lung, oral cavity, larynx, esophagus, and probably cancer of the pancreas.’ (Monograph 9 at 155). However, most cigar smokers are not ‘regular’ smokers, as Monograph 9 recognizes, stating that as many as 75% are merely ‘occasional’ cigar smokers. The FactSheet does not recognize this important qualification, and thus, the statements regarding cancer risk are both incomplete and biased within the meaning of ‘objectivity’ in the HHS Guidelines.”
NCI Response: The overall volume conclusions for Monograph 9 include the statement that “Cigar smoking can cause oral, esophageal, laryngeal and lung cancers. Regular cigar smokers who inhale, particularly those who smoke several cigars per day, have an increased risk of coronary heart disease and chronic obstructive pulmonary disease.” (p. 19) Monograph 9 does not conclude that occasional cigar smokers are free from disease risk. The statement quoted from the fact sheet above accurately characterizes the conclusions of Monograph 9, including acknowledging that the degree of risk varies with the degree of exposure to cigar smoke.
Summary and Conclusions
Once again, we thank you for your comments and questions regarding the Cigar Smoking and Cancer fact sheet. As noted previously, NCI fact sheets are not intended to describe the state of the science on specific topics in the level of detail raised in your letter, but we are pleased to provide additional information herein. More information about the health risks of cigar use is provided in the reports referenced above.
In particular, your “Information Quality Request for Correction” letter suggests that, because cigar smokers typically do not inhale cigar smoke or may smoke infrequently, their health risks may be lower than those of cigarette smokers. As described above, a substantial body of evidence demonstrates that cigar smoking can cause oral, esophageal, laryngeal, and lung cancers. Although some epidemiologic studies have shown lower risks for some cancers among cigar smokers compared with cigarette smokers, there is substantial variability across products and cigar smoking behaviors that precludes drawing broad conclusions about differences in individual risk. For example, evidence suggests that a former cigarette smoker who switches to cigars or a smoker who smokes little cigars regularly may exhibit smoking behavior similar to that of a typical cigarette smoker. Thus, the evidence is insufficient to conclude that risks are necessarily lower for cigar smokers or that a cigarette smoker who switches to smoking cigars will reduce their risk of disease.
Furthermore, the available evidence is insufficient to confirm that there is any “safe” level of cigar smoking. Epidemiologic studies have shown that cancer risks increase with the amount of cigar smoking. The failure to detect an increased risk among cigar smokers at the lowest exposure levels in an epidemiologic study, or the lack of data for this low exposure group, is not adequate to conclude that there is no cancer risk.
In conclusion, we believe the Cigar Smoking and Cancer fact sheet is accurate and supported by the best available evidence. NCI plans no changes to this fact sheet based on your request. A list of references cited in this response is appended.
You may appeal this decision either in writing or electronically within 30 days of receiving this response. Your request should state the reasons for your appeal. It does not need to reference a tracking number. The request may be sent electronically toInfoQuality@od.nih.gov or in hard copy to the Associate Director for Communications, Office of the Director, National Institutes of Health, Building 1, Room 344, 1 Center Drive, Bethesda, Maryland 20892. If the appeal is sent in hard copy, please clearly mark the appeal and outside envelope with the phrase "Information Quality Appeal."
Finally, please note that we appreciate every opportunity to conduct additional reviews of our fact sheets and update them as needed.
Richard E. Manrow, Ph.D.
Associate Director, Office of Cancer Content Management
Office of Communications and Education
National Cancer Institute, National Institutes of Health
6116 Executive Blvd., Suite 300A
Rockville, MD 20852
1International Agency for Research on Cancer. Tobacco smoke and involuntary smoking: summary of data reported and evaluation.IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 83, 1179-87. International Agency for Research on Cancer, Lyon, France, 2002. Available at: http://monographs.iarc.fr./ENG/Monographs/vol83/mono83-6E.pdf.
2International Agency for Research on Cancer. Smokeless Tobacco and Some Tobacco-specific N-Nitrosamines. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 89 . International Agency for Research on Cancer, Lyon, France, 2007. Available at:http://monographs.iarc.fr/ENG/Monographs/vol89/mono89.pdf.
3U.S. Department of Health and Human Services. How tobacco smoke causes disease: the biology and behavioral basis for smoking-attributable disease. A report of the Surgeon General. Rockville: U.S. Dept. of Health and Human Services, Public Health Service, Office of Surgeon General; 2010. Available at: http://www.surgeongeneral.gov/library/tobaccosmoke/report/full_report.pdf.
4Delnevo CD, Bover-Manderski MT, Hrywna M. Cigar, marijuana, and blunt use among US adolescents: Are we accurately estimating the prevalence of cigar smoking among youth? Prev Med. 2011 Jun 1;52(6):475-6. PubMed link:http://www.ncbi.nlm.nih.gov/pubmed/21443900.
5Marshall L, Schooley M, Ryan H, Cox P, Easton A, Healton C, Jackson K, Davis KC, Homsi G; Centers for Disease Control and Prevention. Youth tobacco surveillance — United States, 2001-2002. MMWR Surveill Summ. 2006 May 19;55(3):1-56. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16708059.
6Malone RE, Yerger V, Pearson C. Cigar risk perceptions in focus groups of urban African American youth. J Subst Abuse. 2001;13(4):549-61. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11775082.
7Jolly DH. Exploring the use of little cigars by students at a historically black university. Prev Chronic Dis. 2008 Jul;5(3):A82. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/18558032.
8Soldz S, Huyser DJ, Dorsey E. Youth preferences for cigar brands: rates of use and characteristics of users. Tob Control. 2003 Jun;12(2):155-60. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12773725.
9McCormack VA, Agudo A, Dahm CC, Overvad K, Olsen A, Tjonneland A, Kaaks R, Boeing H, Manjer J, Almquist M, Hallmans G, Johansson I, Chirlaque MD, Barricarte A, Dorronsoro M, Rodriguez L, Redondo ML, Khaw KT, Wareham N, Allen N, Key T, Riboli E, Boffetta P. Cigar and pipe smoking and cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC). Int J Cancer. 2010 Nov 15;127(10):2402-11. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/20162568.
10Bertuccio P, La Vecchia C, Silverman DT, Petersen GM, Bracci PM, Negri E, Li D, Risch HA, Olson SH, Gallinger S, Miller AB, Bueno-de-Mesquita HB, Talamini R, Polesel J, Ghadirian P, Baghurst PA, Zatonski W, Fontham ET, Bamlet WR, Holly EA, Lucenteforte E, Hassan M, Yu H, Kurtz RC, Cotterchio M, Su J, Maisonneuve P, Duell EJ, Bosetti C, Boffetta P. Cigar and pipe smoking, smokeless tobacco use and pancreatic cancer: an analysis from the International Pancreatic Cancer Case-Control Consortium (PanC4). Ann Oncol. 2011 Jun;22(6):1420-6. PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/22104574.
11Rodriguez J, Jiang R, Johnson WC, MacKenzie BA, Smith LJ, Barr RG. The association of pipe and cigar use with cotinine levels, lung function, and airflow obstruction: a cross-sectional study. Ann Intern Med. 2010 Feb 16;152(4):201-10. PubMed link:http://www.ncbi.nlm.nih.gov/pubmed/22104574.
12Henningfield JE, Fant RV, Radzius A, Frost S. Nicotine concentration, smoke pH and whole tobacco aqueous pH of some cigar brands and types popular in the United States. Nicotine Tob Res. 1999 Jun;1(2):163-8. PubMed link:http://www.ncbi.nlm.nih.gov/pubmed/11072397.