Perceptual and Motor Skills, 1991, 72, 112-1 14. O Perceptual and Motor Skills 1991
BREAST CANCER AND CEREBRAL LATERALITY ' WAYNE P. LONDON
Dartmouth Medical School
AND
SUSAN A. ALBRECHT
School of Nursing University of Pittsburgh
Summary.-In reviewing and summarizing work at our institution, we have identified some surprising consistencies in patients with breast cancer. Breast cancer shows four features of cerebral laterality: excess left-handedness, atypical season-of-birth patterns, the risk factor of advanced maternal age, and an association with prenatal sex hormones. Since hypopigmentation also relates to cerebral laterality, a consequence of the association of breast cancer and cerebral laterality is chat eye color should be measured as a function of side of disease and age at diagnosis in women with breast cancer.
Breast cancer shows four features associated with cerebral laterality: excess left-handedness, atypical season-of-birth patterns, the risk factor of advanced maternal age, and an association with prenatal sex hormones. Excess left-handedness: In a pilot study in 1981, Sister Mary Albert Kramer observed an association between handedness and left-sided breast cancer (5). In 1985 Kramer, Albrecht, and Miller (6) extended the study to a sample of 1,027 women and showed that left-handedness was nearly a two-fold risk factor for developing breast cancer prior to age 45, and nearly a thee-fold risk factor for developing left-sided breast cancer prior to age 45. These findings require replication. [Left-sided breast cancer differs from right-sided breast cancer in several important ways (1, 7).] Atypical season-of-birth patterns: Many biological phenomena associated with increased frequency of left-handedness also show an atypical season-of-birth pattern and vice versa, that is, individuals showing the phenomena are not born unifordy throughout the year as are individuals in the general population. These phenomena include neurological disorders (schizophrenia, manic-depressive illness, alcoholism, Alzheimer's disease, and autism); left-handedness; blue and hazel eyes; immune disorders (thyroid disorder and allergy); birth defects (cleft palate and neural tube defects); chromosomal abnormalities [Down syndrome (trisomy of chromosome 21), Klinefelter syndrome (XX, Y), and Turner syndrome (X, 0)l;twins, lower life expectancy, and superior mathematical ability (1, 2, 3, 4, 8). Six samples of women with breast cancer show atypical season-of-birth patterns-samples from Greece, Japan, United States, Pennsylvania, New Hampshire, and Pittsburgh (2). Four samples-from Japan, Pennsylvania, New Hampshire, and Pittsburgh-show atypical season-of-birth patterns in
'Send requests for reprints to Dr. Susan A. Albrecht, 330 Wray Large Road, Jefferson Boro., Pittsburgh, PA 115025.
BREAST CANCER AND CEREBRAL LATERALITY
113
women with premenopausal or perimenopausal disease. Three samplesPennsylvania, New Hampshire, and Pittsburgh-show the dual pattern of excess winter and summer births in early-onset breast cancer. Two samples-Pennsylvania and Pittsburgh-show excess winter births in premenopausal left-sided disease. Maternal age and prenatal sex hormones: Advanced maternal age, which is a risk factor for left-handedness and for two phenomena associated with cerebral laterality-Down syndrome and schizophrenia (3)-is also a risk factor for breast cancer (9). In addition, levels of prenatal sex hormones are associated with advanced maternal age (9) and the development of both left-handedness (3, 4) and breast cancer (9). Hypopigmentation also relates to cerebral lateral it^ (8). Left-handed men are more frequently blue-eyed, and individuals with blond hair, particularly men, are more frequently left-handed. Males with the attention deficit disorder or learning disabilities show an increased frequency of both lefthandedness and light pigment. Finally, in the USA eye color shows an atypical season-of-birth pattern: hazel-eyed females and blue-eyed males are born more frequently in the spring and summer, according to unpublished work by W. P. London, entitled Excess spring-summer births of hazel-eyed females and blue-eyed males (submitted for publication). The association of both breast cancer and hypopigmentation with cerebral laterality suggests that eye color should be measured as a function of side of disease and age at diagnosis of women with breast cancer. Like excess left-handedness and atypical season-of-birth patterns, hypopigmentation might be found in early onset, that is, premenopausal or perimenopausal breast cancer. In addition, hypopigmentation might also be associated with premenopausal left-sided disease, which is associated with both excess left-handedness and excess winter births. Other consequences of the association of breast cancer and cerebral laterality include: (a) prenatal environmental factors, such as season of birth (or season of conception) and advanced maternal age, which possibly involve levels of prenatal sex hormones, are implicated in the development of breast cancer as an adult. (b) If some women develop breast cancer because of these prenatal environmental factors, their offspring . - need not be considered at increased risk for breast cancer. (c) Women having traits associated with cerebral laterality such as left-handedness, learning disorders, alcoholism, or thyroid disorders (3, 4, 8), might be more prone to develop, and should be more closely screened for, early-onset breast cancer.
1. ALBRECHT, S. A., & LONDON,W. I? Remrch, 1990, 39, 118-120.
REFERENCES Season of birth and laterality of breast cancer. Nursing
114
W. P LONDON & S. A. ALBRECHT
2. ALBRECHT, S. A,, & LONDON, W. I? Season of birth and earlv-onset breast cancer. (Submitted for publication) 3. COREN,S. (Ed.) Left-handedness: behauioralimplicationsand anomalies Amsterdam, The Netherlands: Elsevier, 1990. 4. GESCHWIND, N., & G A I . ~ U R DA A M. , Cerebral Lferalization, biological mechanisms, associations and pathology Cambridge, M A : MIT Press, 1987. 5. KRAMER,SR. M. A I-landeclness and the laterality of female breast cancer. (Unpublished manuscript, Umver. of Pittsburgh, School of Nursing, Pittsburgh) 6 . KMER, M A., ALBRECHT, S., & MILLER,R. A. Handedness and the laterality of breast cancer m women. Nursing Research, 1985, 34, 333-337. 7. KRAMER, M. A,, ALBRECHT, S., & MILLER,R. A. Higher frequency of left-sided breast cancer: a possible explanation. Perceptual and Motor Skills, 1985, 61, 583-588. 8. LONDON, W. P. Left-handedness and alcoholism. In S. Coren (Ed.), Left-handedness: behauioral implications and anomalies. Amsterdam, The Netherlands: Elsevier, 1990. Pp. 457-484. 9. TRICHOPOULOS, D. Hypothesis: does breast cancer originate in utero? Lancet, 1990, 335, 939-940.
Accepted January 21, 1991.
BREAST CANCER AND CEREBRAL LATERALITY ' WAYNE P. LONDON
Dartmouth Medical School
AND
SUSAN A. ALBRECHT
School of Nursing University of Pittsburgh
Summary.-In reviewing and summarizing work at our institution, we have identified some surprising consistencies in patients with breast cancer. Breast cancer shows four features of cerebral laterality: excess left-handedness, atypical season-of-birth patterns, the risk factor of advanced maternal age, and an association with prenatal sex hormones. Since hypopigmentation also relates to cerebral laterality, a consequence of the association of breast cancer and cerebral laterality is chat eye color should be measured as a function of side of disease and age at diagnosis in women with breast cancer.
Breast cancer shows four features associated with cerebral laterality: excess left-handedness, atypical season-of-birth patterns, the risk factor of advanced maternal age, and an association with prenatal sex hormones. Excess left-handedness: In a pilot study in 1981, Sister Mary Albert Kramer observed an association between handedness and left-sided breast cancer (5). In 1985 Kramer, Albrecht, and Miller (6) extended the study to a sample of 1,027 women and showed that left-handedness was nearly a two-fold risk factor for developing breast cancer prior to age 45, and nearly a thee-fold risk factor for developing left-sided breast cancer prior to age 45. These findings require replication. [Left-sided breast cancer differs from right-sided breast cancer in several important ways (1, 7).] Atypical season-of-birth patterns: Many biological phenomena associated with increased frequency of left-handedness also show an atypical season-of-birth pattern and vice versa, that is, individuals showing the phenomena are not born unifordy throughout the year as are individuals in the general population. These phenomena include neurological disorders (schizophrenia, manic-depressive illness, alcoholism, Alzheimer's disease, and autism); left-handedness; blue and hazel eyes; immune disorders (thyroid disorder and allergy); birth defects (cleft palate and neural tube defects); chromosomal abnormalities [Down syndrome (trisomy of chromosome 21), Klinefelter syndrome (XX, Y), and Turner syndrome (X, 0)l;twins, lower life expectancy, and superior mathematical ability (1, 2, 3, 4, 8). Six samples of women with breast cancer show atypical season-of-birth patterns-samples from Greece, Japan, United States, Pennsylvania, New Hampshire, and Pittsburgh (2). Four samples-from Japan, Pennsylvania, New Hampshire, and Pittsburgh-show atypical season-of-birth patterns in
'Send requests for reprints to Dr. Susan A. Albrecht, 330 Wray Large Road, Jefferson Boro., Pittsburgh, PA 115025.
BREAST CANCER AND CEREBRAL LATERALITY
113
women with premenopausal or perimenopausal disease. Three samplesPennsylvania, New Hampshire, and Pittsburgh-show the dual pattern of excess winter and summer births in early-onset breast cancer. Two samples-Pennsylvania and Pittsburgh-show excess winter births in premenopausal left-sided disease. Maternal age and prenatal sex hormones: Advanced maternal age, which is a risk factor for left-handedness and for two phenomena associated with cerebral laterality-Down syndrome and schizophrenia (3)-is also a risk factor for breast cancer (9). In addition, levels of prenatal sex hormones are associated with advanced maternal age (9) and the development of both left-handedness (3, 4) and breast cancer (9). Hypopigmentation also relates to cerebral lateral it^ (8). Left-handed men are more frequently blue-eyed, and individuals with blond hair, particularly men, are more frequently left-handed. Males with the attention deficit disorder or learning disabilities show an increased frequency of both lefthandedness and light pigment. Finally, in the USA eye color shows an atypical season-of-birth pattern: hazel-eyed females and blue-eyed males are born more frequently in the spring and summer, according to unpublished work by W. P. London, entitled Excess spring-summer births of hazel-eyed females and blue-eyed males (submitted for publication). The association of both breast cancer and hypopigmentation with cerebral laterality suggests that eye color should be measured as a function of side of disease and age at diagnosis of women with breast cancer. Like excess left-handedness and atypical season-of-birth patterns, hypopigmentation might be found in early onset, that is, premenopausal or perimenopausal breast cancer. In addition, hypopigmentation might also be associated with premenopausal left-sided disease, which is associated with both excess left-handedness and excess winter births. Other consequences of the association of breast cancer and cerebral laterality include: (a) prenatal environmental factors, such as season of birth (or season of conception) and advanced maternal age, which possibly involve levels of prenatal sex hormones, are implicated in the development of breast cancer as an adult. (b) If some women develop breast cancer because of these prenatal environmental factors, their offspring . - need not be considered at increased risk for breast cancer. (c) Women having traits associated with cerebral laterality such as left-handedness, learning disorders, alcoholism, or thyroid disorders (3, 4, 8), might be more prone to develop, and should be more closely screened for, early-onset breast cancer.
1. ALBRECHT, S. A., & LONDON,W. I? Remrch, 1990, 39, 118-120.
REFERENCES Season of birth and laterality of breast cancer. Nursing
114
W. P LONDON & S. A. ALBRECHT
2. ALBRECHT, S. A,, & LONDON, W. I? Season of birth and earlv-onset breast cancer. (Submitted for publication) 3. COREN,S. (Ed.) Left-handedness: behauioralimplicationsand anomalies Amsterdam, The Netherlands: Elsevier, 1990. 4. GESCHWIND, N., & G A I . ~ U R DA A M. , Cerebral Lferalization, biological mechanisms, associations and pathology Cambridge, M A : MIT Press, 1987. 5. KRAMER,SR. M. A I-landeclness and the laterality of female breast cancer. (Unpublished manuscript, Umver. of Pittsburgh, School of Nursing, Pittsburgh) 6 . KMER, M A., ALBRECHT, S., & MILLER,R. A. Handedness and the laterality of breast cancer m women. Nursing Research, 1985, 34, 333-337. 7. KRAMER, M. A,, ALBRECHT, S., & MILLER,R. A. Higher frequency of left-sided breast cancer: a possible explanation. Perceptual and Motor Skills, 1985, 61, 583-588. 8. LONDON, W. P. Left-handedness and alcoholism. In S. Coren (Ed.), Left-handedness: behauioral implications and anomalies. Amsterdam, The Netherlands: Elsevier, 1990. Pp. 457-484. 9. TRICHOPOULOS, D. Hypothesis: does breast cancer originate in utero? Lancet, 1990, 335, 939-940.
Accepted January 21, 1991.
