L.A. von Schuckmann , A.C. Green , J.C. van der Pol
Introduction: There is evidence that progenitor cells of
keratinocyte skin cancers (basal cell carcinoma (BCC) and
squamous cell carcinoma (SCC)) may originate from hair
follicle stem cells.
A high density of hair follicles on
human skin may therefore increase keratinocyte skin
cancer risk. Conversely, dense body hair coverage may
provide a barrier against ultraviolet radiation and may
decrease keratinocyte skin cancer risk.
Objective: To evaluate associations between the density of
body hair and development of keratinocyte skin cancers in
Method: Density and colour of hair on the mid forearm of
715 participants (originally randomly selected) in a
community-based cohort study of skin cancer, was assessed
clinically against reference photographs. Associations of
dense vs sparse forearm hair with occurrence of BCC and
SCC (237 and 115 persons affected respectively) in the 20
preceding years were assessed using multivariate regression
analysis with adjustment for age, sex, phenotypic characteristics
and markers of chronic sun exposure.
Results: After adjusting for confounders, participants with
dense forearm hair had higher incidence rate ratios of
BCC (IRR = 2.24, 95% CI: 1.20, 4.18, P = 0.01) and SCC
(IRR = 2.80, 95% CI: 1.20, 6.57, P = 0.02) compared to individuals
with sparse forearm hair. When stratiﬁed by sex,
women with moderate vs. sparse hair density were more
likely affected by BCC (IRR = 2.29, 95% CI 1.05, 5.00,
P = 0.04).
Conclusion: Dense forearm hair may be associated with
increased BCC and SCC risk. We found no evidence that
forearm hair affords protection against keratinocyte skin