Men with a certain type of baldness may be at a higher risk of developing aggressive prostate cancer, according to a new analysis from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.
The risk was observed in men who had moderate baldness that affected both the front and the crown of their head by age 45 years, as compared with men with no baldness.
Other patterns of baldness were not significantly associated with overall or subtypes of prostate cancer.
There was a suggestion of a higher risk for overall prostate cancer (~20%) related to frontal plus vertex balding at age 45 years, compared with no balding at age 45 years, but this was not statistically significant, commented senior study author Michael B. Cook, PhD, an investigator in the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Bethesda, Maryland.
He noted that that they did not have confidence that it deviated from "no association."
"However, when we split the prostate cancer cases into aggressive and nonaggressive, aggressive prostate cancer risk was increased by 40% while there was no altered risk of nonaggressive prostate cancer," Dr. Cook told Medscape Medical News.
The study was published online September 15 in the Journal of Clinical Oncology.
Male pattern baldness and prostate cancer appear to share common pathophysiologic mechanisms, and although some research has suggested a link, results from previous studies have been inconsistent.
The current article is the largest individual study to assess male pattern baldness in relation to prostate cancer risks, but Dr. Cook cautions that these results are not practice changing. "There is a wide confidence in our estimated 40% increased risk of aggressive prostate cancer in those with frontal plus moderate vertex balding at age 45 years, compared with men with no balding at age 45 years," he said. "The lower confidence limit suggests just a 7% increased risk in these men."
Replication of these results is required, as is a better mechanistic understanding. "It is conceivable that in the future, male pattern baldness may play a small role in estimating risk of prostate cancer and may contribute to patient-doctor discussions about whether to opt for prostate cancer screening," Dr. Cook added. "At this time, however, these results should be interpreted in a conservative fashion. Men with any pattern of male pattern baldness at age 45 years should not be additionally concerned about their individual risk of prostate cancer."
Study Details
Dr. Cook and colleagues analyzed male pattern baldness in relation to prostate cancer risk in a cohort of 39,070 men from the US PLCO Cancer Screening Trial who were between the ages of 55 and 74 years at enrollment. The men received a questionnaire that asked them to recall what their hair-loss patterns were at age 45, using a pictorial tool.
Male pattern baldness at age 45 years was reported by 53.4% of the cohort, with 46.4% reporting only frontal baldness, 23.5% with frontal plus mild vertex baldness, 18.1% with frontal plus moderate vertex baldness, and 12.0% with frontal plus severe vertex baldness.
At a median follow-up of 2.78 years, a total of 1138 incident prostate cancers were diagnosed, and of these, 571 were aggressive (Gleason score equal to or greater than 7, stage III or IV, or prostate cancer as the cause of death). The mean age at the time of prostate cancer diagnosis was 72.
As compared with men who were not bald, those with frontal plus moderate vertex baldness at age 45 years did not have a significantly higher risk for prostate cancer overall (hazard ratio [HR], 1.19; 95% confidence interval [CI], 0.98 - 1.45) or with nonaggressive disease (HR, 0.97; 95% CI, 0.72 - 1.30). It was, however, significantly associated with an increased risk for aggressive prostate cancer (HR, 1.39; 95% CI, 1.07 - 1.80).
Adjusting for covariates did not substantially alter these results, note the authors.
No Changes in Practice Yet
"Previous research linking baldness and prostate cancer has been inconclusive, but this large study suggests a significant link between high-risk prostate cancer and hair loss ― and suggests that men with hair loss may need to be followed more closely," commented Charles Ryan, MD, professor of clinical medicine and urology at the Helen Diller Family Comprehensive Cancer Center at the University of California, San Francisco, in a statement. Dr. Ryan was not involved in the study.
He agrees with Dr. Cook that these results are not yet practice changing and that more evidence is needed "before we can routinely consider baldness in prostate cancer screening recommendations."
The study was supported by the Intramural Program of the Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health. The authors have disclosed no relevant financial relationships.
J Clinical Oncol. Published online Sept. 15, 2014. Abstract
Medscape Medical News © 2014 WebMD, LLC
Send comments and news tips to news@medscape.net.
Cite this: Male Pattern Baldness Linked to Aggressive Prostate Cancer - Medscape - Sep 15, 2014.
Comments