Poorer Treatment Response in Cancer Patients
Evidence exists for substantial
medical advantage to an individual quitting smoking once cancer is diagnosed. There is substantial
evidence that continued smoking may reduce the effectiveness of treatment and
increase the likelihood of a second cancer (refer to the Smoking as a Risk for Second Malignancy section of this summary for further information). Continued smoking may also worsen
side effects of treatment,[1] though the direct evidence for this is
surprisingly limited because few studies have evaluated this issue. If one
extrapolates, however, from the extensive evidence of the effects of smoking on
cardiovascular disease, pulmonary functioning, immunosuppression, and wound
healing due to vasoconstriction, as well as the fairly rapid reduction of some effects
following smoking cessation,[2] these results might also apply to cancer
patients, particularly if surgical management or lung functioning is involved.
More specifically, one study outlines a model of cardiopulmonary toxicities in
response to various antineoplastic therapies that may be potentiated by tobacco
use; for example, smokers treated with bleomycin or carmustine would evidence
higher levels of pulmonary fibrosis and restrictive lung disease, and the
anthracyclines would lead to higher risk of cardiomyopathy in smokers.[3] In a
study of advanced head and neck cancer patients receiving radiation therapy,[4]
patients who continued to smoke suffered mucositis for a longer
time (23.4 weeks) than did either patients who quit at the time of radiation
therapy and remained abstinent (13.6 weeks) or patients who remained abstinent for at
least a month after treatment (18.3 weeks). Extended mucositis may be associated
with permanent alteration in appearance. In one study, patients receiving induction chemotherapy for acute myeloid leukemia who continued to smoke were more likely to experience severe pulmonary infection (26% vs. 18%), although overall survival rates did not differ in adults older than 60 years.[5] Following radiation therapy for
laryngeal carcinoma, patients who continue to smoke may be less likely to
regain satisfactory voice quality.[6] Another area of reasonable concern for
patients who continue to smoke is the rate of general complications
following any type of surgery; it is documented that wound healing postsurgery is slowed in smokers because both nicotine and carbon monoxide cause
vasoconstriction, inhibition of epithelization, and creation of a cellular
hypoxia.[7,8] In one study of predictors of complications following resection
in lung cancer patients, a history of smoking doubled the likelihood of
complications, but smoking at time of admission for surgery did not.[9] No
detailed information is provided, however, regarding the time since smoking
ceased.
One study found decreased response rates and survival rates in head and neck
cancer patients who continued to smoke. Patients who continued to smoke had a
significantly lower rate of complete response to radiation therapy (45% vs.
74%) and 2-year survival (39% vs. 66%). Recent quitters were more similar to
long-term quitters than to continued smokers in survival likelihood at 18
months.[10]
Another study also showed an effect on survival rates of continued smoking in
head and neck cancer patients.[11] Those who stopped
smoking had double the chance of survival, irrespective of extent of disease at
diagnosis; after 2 years, survival of quitters approached that of
nonsmokers. Relative risk for recurrence was about double in quitters and
quadrupled in those who continued to smoke, regardless of the amount they
smoked. One study failed to find significant differences in prognosis in
resected stage I non-small cell lung cancer patients dependent on smoking
status; the recurrence and death rates in both former and current smokers did
not differ but were double to triple those of newer smokers.[12] These
differences failed, however, to reach statistical significance because of the small
number of newer smokers; in addition, the lack of differences between former versus current
smokers is hard to interpret because no definitions are provided. One study found a
consistent trend in small cell cancer patients: continued smokers had the
poorest survival, followed by patients who quit at diagnosis, then by
patients who had quit on average 2.5 years before diagnosis.[13] Although
survival curves of recent ex-smokers did not differ statistically from
continued smokers, perhaps because of small numbers, no continued smokers (n = 57)
survived past 131 weeks, whereas 6 of those who quit at diagnosis (n = 35) were
in complete remission at 1 to 2 years. The relationship between smoking and
progression of prostate cancer has also been examined. Another study found a
much higher 5-year tumor-specific mortality rate among smokers with stage D2
disease (88% vs. 63%) or non–stage A disease (39% vs. 17%), which was attributed
to the effects of continued smoking as an immunosuppressant.[14] Yet another
study found longer survival rates in prostate cancer patients who are
nonsmokers, but this study did not examine the effects of quitting.[15]
Survival and recurrence data for lung cancer are mixed.
References
-
Des Rochers C, Dische S, Saunders MI: The problem of cigarette smoking in radiotherapy for cancer in the head and neck. Clin Oncol (R Coll Radiol) 4 (4): 214-6, 1992.
[PUBMED Abstract]
-
U.S. Department of Health and Human Services.: The Health Benefits of Smoking Cessation. A Report of the Surgeon General. Rockville, Md: 1990. DHHS Publ No. (CDC) 90-8416.
-
Tyc VL, Hudson MM, Hinds P, et al.: Tobacco use among pediatric cancer patients: recommendations for developing clinical smoking interventions. J Clin Oncol 15 (6): 2194-204, 1997.
[PUBMED Abstract]
-
Rugg T, Saunders MI, Dische S: Smoking and mucosal reactions to radiotherapy. Br J Radiol 63 (751): 554-6, 1990.
[PUBMED Abstract]
-
Chelghoum Y, Danaïla C, Belhabri A, et al.: Influence of cigarette smoking on the presentation and course of acute myeloid leukemia. Ann Oncol 13 (10): 1621-7, 2002.
[PUBMED Abstract]
-
Karim AB, Snow GB, Siek HT, et al.: The quality of voice in patients irradiated for laryngeal carcinoma. Cancer 51 (1): 47-9, 1983.
[PUBMED Abstract]
-
Gritz ER, Kristeller J, Burns DM: Treating nicotine addiction in high-risk groups and patients with medical co-morbidity. In: Orleans CT, Slade J, eds.: Nicotine Addiction: Principles and Management. New York, NY: Oxford University Press, 1993, pp 279-309.
-
U.S. Department of Health and Human Services.: The Health Consequences of Smoking: Cardiovascular Disease. A Report of the Surgeon General. Rockville, Md.: DHHS Publication No. (PHS) 84-50204, 1983.
-
Kearney DJ, Lee TH, Reilly JJ, et al.: Assessment of operative risk in patients undergoing lung resection. Importance of predicted pulmonary function. Chest 105 (3): 753-9, 1994.
[PUBMED Abstract]
-
Browman GP, Wong G, Hodson I, et al.: Influence of cigarette smoking on the efficacy of radiation therapy in head and neck cancer. N Engl J Med 328 (3): 159-63, 1993.
[PUBMED Abstract]
-
Stevens MH, Gardner JW, Parkin JL, et al.: Head and neck cancer survival and life-style change. Arch Otolaryngol 109 (11): 746-9, 1983.
[PUBMED Abstract]
-
Gail MH, Eagan RT, Feld R, et al.: Prognostic factors in patients with resected stage I non-small cell lung cancer. A report from the Lung Cancer Study Group. Cancer 54 (9): 1802-13, 1984.
[PUBMED Abstract]
-
Johnston-Early A, Cohen MH, Minna JD, et al.: Smoking abstinence and small cell lung cancer survival. An association. JAMA 244 (19): 2175-9, 1980.
[PUBMED Abstract]
-
Daniell HW: A worse prognosis for smokers with prostate cancer. J Urol 154 (1): 153-7, 1995.
[PUBMED Abstract]
-
Bako G, Dewar R, Hanson J, et al.: Factors influencing the survival of patients with cancer of the prostate. Can Med Assoc J 127 (8): 727-9, 1982.
[PUBMED Abstract]
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