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Research
Risk of breast cancer in women with palpable breast cysts
Breast Cancer References:
I. Lymphatic Flow
II. Fibrocystic Changes
III. Effects of Clothing
IV. Hormone Effects
V. Oxidative Stress, Hypoxia, Glutathione
VI. Cup Size, Obesity
VII. References on breast ligament atrophy
VIII. Miscellaneous
Research relating to bras, breast cancer, and fibrocystic disease
Note: This is a partial listing, by no means exhaustive. Dr. Vaughan's comments are in italics.
In exploring the possibility that bras relate to breast cancer, we are about where we were in the 1950s with respect to cigarettes causing lung cancer. Doctors began to see men present with lung cancer who had a long history of smoking. It took 20-30 years to "prove" the connection and 40 years to prove causation.
I am not alone in my opinion that brasÑparticularly tight bras and underwire brasÑare not good for your breasts.
Dr. Christiane Northrup, M.D., Univ. of Vermont College of Medicine author of "Women's Bodies, Women's Wisdom," wrote: "Stop wearing an underwire bra. Too often this kind of bra cuts off circulation of both blood and lymph fluid around the breast, chest wall, and surrounding tissue."
Dr. Jesse Hanley, M.D., in her book called "What Your Doctor May Not Tell You About Premenopause," Warner Books, 1999, wrote that she encourages her patients not to wear underwire bras or even tight bras, except for special occasions because they block the lymph glands underneath the breast. Lymph glands play an important role in draining toxins from the breast.
The debate is: How does wearing a bra increase one's risk?
Some researchers feel that the connection is that bras cause breast congestion and slow down lymphatic drainage of the breasts. Toxins that we eat, drink, inhale and absorb through our skin tend to collect in our fat cells. Our breasts are made of breast tissue and fat. So any constricting garment that slows down lymphatic drainage increases the amount of time that these toxins can damage our breast cells.
I've personally treated at least 100 patients who chose to go bra free after yet another biopsy of a lump in their breasts or aspiration of a cyst. Over 3-6 months, their breast cysts/lumps got smaller and less tender and they developed no new lumps that we could detect..
An article in Lancet showed a 5.9 fold increased risk of breast cancer in premenopausal women who had palpable breast cysts compared to those that did not have breast cysts.
Lancet 1999 May 22;353(9166):1742-5
Risk of breast cancer in women with palpable breast cysts: a prospective study. Edinburgh Breast Group.
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Dixon JM, McDonald C, Elton RA, Miller WR Edinburgh Breast Unit, Western General Hospital, UK.
BACKGROUND: 7% of women in the western world develop palpable breast cysts. Studies of the relation between cysts and breast cancer have conflicting results. There are two clearly defined types of cyst. We investigated whether one cyst type is associated with a higher rate of breast-cancer development than the other.
METHODS: We studied 1374 women with palpable breast cysts presenting between 1981 and 1987, who had cysts aspirated between 1981 and 1989. Cysts were classified as type I if the sodium/potassium (Na+/K+) ratio in the cyst fluid was less than 3, or type II if the Na+/K+ ratio was 3 or more. Data on incidence of breast cancer were available until January, 1995, and we compared them with the expected numbers of cancers calculated from age-specific breast-cancer incidence in Scotland in 1988.
FINDINGS: 65 cancers developed during follow-up. The overall standardised incidence rate of breast cancer in patients with palpable cysts was 2.81 (95% CI 2.17-3.59). The relative incidence rate was increased for all cyst types. The standardised incidence rate of developing breast cancer among women younger than 45 years was highest at 5.94 (2.97-10.63), with a significant trend for decreasing relative incidence rate with age (p<0.05). Women older than 54 years had a standardised incidence rate of 1.73 (0.86-3.10). The standardised incidence rate of breast cancer was highest in the first year after aspiration (7.02 [3.73-12.00]) but the risk was still raised after 5 years (2.68 [1.84-3.76]).
INTERPRETATION: Women with breast cysts are at an increased risk of breast cancer, especially at younger ages. The type of cyst did not alter the associated relative incidence rate of breast-cancer development.
PMID: 10347986, UI: 99275742
So my question is: If cysts get smaller when you go brafree, doesn't this logically reduce a women's risk of getting breast cancer or at least delay the development of breast cancer?
Some researchers think it is because the breasts are over-heated when wearing a bra. There is definite evidence that men have lower sperm counts and testosterone levels when they wear briefs instead of boxers. It is well documented in medical textbooks that undescended testicles in little boys are at higher risk of developing cancer (because of being overheated?):
The Lancet, November 4, 1978, P. 1001
Dr. John M. Douglass Department of Internal Medicine, S. Calif. Permanente Med. Center Los Angeles, California
Dr. Adami and Dr. Rimsten (Se 5, p. 677) address a multifactorial problem. Consider these findings: women in upper socioeconomic brackets have more breast cancer than women in lower socioeconomic brackets; women with large breasts have more breast cancer than women with small breasts; nuns have more breast cancer than non-nuns; and Taiwan women, who nurse only on one side, have little cancer in that breast, but a great deal in the other. The common denominator in those women seems to be overheated glandular tissue. I tested this hypothesis by tactually noting breast temperatures of 550 women patients within 30 seconds, if wearing bras, after bra removal. I found that women in upper socioeconomic brackets tended to wear heavier, more expensive bras, making their breasts hotter than lighter-bra-wearing or braless women in lower socioeconomic brackets. Large, bra-encased breasts were hotter than smaller ones, but braless breasts--large, medium, or small--were cool. In addition, I found that nuns bind their breasts, flattening them; this coupled with black, heat-absorbing clothes overheats their breasts. And, of course, nursing Taiwan women have one breast exposed often, making it cooler than the one remaining at a constant hotter temperature.
It is well known that undescended testes have a high cancer incidence due to glandular tissue overheating. Also, testicular cancer increased markedly after men began wearing hotter, jockey-type underwear. I suggest a similar mechanism as one factor in breast cancerÑi.e., if one keeps the breasts hot, they develop more cancer than if one leaves them cool as Nature intended.
Several years ago, when feminists burned their bras, it seemed peculiar; however, they may have been decreasing the risk of breast cancer. Perhaps doctors should encourage them, or at least recommend net or other cool bras when women insist on wearing them.
November 4, 1978 The Lancet, p. 1001
Bujan, L. and R.Mieusset, R. Contraception Fertilite Sexualite 23:611-4(1995) "Male Contraception by Testicular Heating" Holding testes close to the trunk with specific underwear was an effective form of birth control for human couples. The underwear was only worn during waking hours and it only caused a temperature rise of 1 to 2 degrees Centrigrade.
Parazzini, F. et al. Int. J. Andrology 18:137-40 (1995) About twice the rate of dyspermia was found in men who wear tight underpants. They are speaking only of commercially-available underwear and looked at loose versus tight. "Likewise, the odds ration of dyspermia was 1.6 in men reporting usually wearing tight trousers (including jeans), in comparison with those wearing loose trousers."
Lastly, it is well accepted that women who exercise have a lower risk of breast cancer. So, movement of the breasts reduces breast cancer. Breasts move less in a constricted bra. Lymphatic flow is enhanced by movement.
No one is saying that bra abstinence will eradicate breast cancer, or even all cases of fibrocystic breast disease. However, the evidence for a connection is certainly sufficient for further study by the medical community. Meanwhile, individual women with or without fibrocystic conditions have a promising alternative that they can try for themselves.
Who, I ask, will be harmed by women going bra free or wearing less constrictive bras?
Here is a long list of articles that suggest a connection between wearing bras and deterioration in breast health.
Breast Cancer References
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This list of references was inspired by the work of Singer and Grismaijer, who, in a study of almost 5000 women, demonstrated a link between breast cancer rates and the wearing of bras. Since no other studies have been published, this list of medical and scientific references was assembled to provide a background for discussion and further research.
I. Lymphatic Flow
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One hypothesis is that restriction of lymphatic flow by bras could, by several possible mechanisms, cause breast disease.
Schmid-Schonbein, G.W. - Lymphatic text - Lymphatic circulation is dependent on muscle contraction and movement. Even the passive movement of a limb causes an increase in lymph flow rates.
Ikomi, F. et al. Radiology 196:107-13(1995) Lymph flow rates increased substantially with massage in studies of the hind feet of rabbits. "External tissue movement contributes substantially to the rate..."
Zawieja, D.C. et al. Am. J. Physiol. 260:H1935-43(1991) "Exposure to oxyradicals inhibited the lymphatic pumping mechanism." "We conclude that oxyradicals significantly inhibit the lymph pump and that this inhibition could be a factor contributing to the function of interstitial edema during inflammation." [Consider that constriction by garments -- hampered lymph flow -- anoxia -- buildup of toxins and cellular waste products --oxyradical buildup -- more reduction in lymph flow.]
II. Fibrocystic Changes
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Some types of fibrocystic lumps are correlated with higher breast cancer rates. Some unpublished preliminary studies by S. Singer and colleagues shows that fibrocystic breasts can be successfully treated by the stopping of bra wearing. Much anecdotal evidence also supports this.
Gross, A. et al. Radiol.-Med.-Torino 91:194-7 (1996) Type I cysts (apocrine)(potassium greater than sodium) correlated with higher risk of breast cancer.
Ardizzoja, M. et al. Anticancer Res. 14:555-9 (1994) "Natural killer (NK) cell activity of women with gross cystic disease is inhibited in vitro by breast cyst fluid." Breast cyst fluid aspirated from patients with gross cystic disease was able to inhibit natural killer cell activity of NK cells from the same woman. "Our data are compatible with an immunosupressive effect of BCF, potentially leading to altered local immunosurveillance."
J.M. Dixon, et al. Breast, 6: pp. 12-16 "The uptake of DHA sulphate into human breast cyst fluids." This research showed that breast cysts can concentrate steroids from the blood plasma and that the steroids can remain trapped there for at least TWO YEARS. "Even at 2 years after infusion detectable levels of radioactivity were present in breast cyst fluids. Although the clinical significance remains to be determined, it demonstrates that breast epithelium many actively concentrate and retain substances from plasma. This means that breast epithelium may be exposed to high concentrations of xeno-biologicals for prolonged periods." Basically, they are saying that breast cysts (type I in this case) are very stagnant pools and that they can concentrate steroids.
Bodian, C. et al., Cancer, 71: 3896-97 (1993) "Benign proliferative breast disease recognized in biopsy specimens is associated with an increased risk of future breast cancer." Depending on the type of cyst or lump, the relative risk is as high as 3.9.
Lai, L.C. Cancer-Detect.-Prev. 19:441-5 (1995) Breast cyst fluid has high concentrations of androgens and estrogens, some of which have been implicated in mammary carcinogenesis. "Steroid metabolism by breast cysts may play a role in the development of breast cancer." [consider constriction by bras -- lower lymph flow -- blocked ducts -- cysts -- altered hormone metabolism]
Deschamps, M. et al. Cancer Detect.-Prev. 20:610-9 (1996) "Cyclical tenderness and breast swelling may carry an increased breast cancer risk."
Torrisi, R. et al. Breast Cancer Res. Treatment 33:219-24 (1995) "Epidermal growth factor levels are higher in cysts aspirated from breasts with an associated pathology, either benign or nepotistic." [This supports the increased risk of breast cancer of some types of benign breast lumps.]
Simiockova, M. et al. Neoplasma 41:245-52 (1994) "The occurrence of breast cancer in patients with gross cystic disease is two to five times higher as compared to control groups of women."
Fiorica, J.V. Obstet.-Gynecol.-Clin.-North-Am. 21:445-52 (1994) "Fibrocystic changes" Fibrocystic changes are defined as "a condition where there are palpable lumps in the breast, usually associated with pain and tenderness that fluctuate with the menstrual cycle." Risk factors for fibrocystic changes are nulliparity, late age of natural menopause, and high social class [these are also proven risk factors for breast cancer.] The authors recommend 24-hour wear of a support bra!, but they give no supporting data for this. "Vitamin E has been shown to be effective in controlling mastalgia." Women with lumps with cellular atypia and a family history of breast cancer have an 11- fold higher risk of breast cancer. "Most women have fibrocystic changes in their breasts. Patients with proliferative changes with atypia are at an increased risk of breast cancer. Clinically the types and variants of fibrocystic changes are sometimes difficult to distinguish."
"The fluid aspirated from the cyst may be straw colored or dark brown to green. The color varies according to the chronicity of the cyst."
Zanardi, Z. et al. Int. J. Cancer 59:725-7 (1994) Type I benign breast cysts "contain high levels of EGF, a growth-stimulating factor, and very low levels of TGF-beta 1, a growth inhibiting factor."
Angeli, A. et al. J.Steroid Biochem. Mol. Biol. 49:333-0 (1994) The fluid from macrocysts contains high amounts of steroid conjugates (metabolites of bodily steroids).
Hockenberger, S.J. Plast-Surg-Nurs 13: 37-40 (1993) "Ninety percent of all women experience evidence of pathophysiologic changes in the breast during their lifetime."
III. Effects of Clothing
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The harmful effects of certain articles of clothing have been documented throughout history, from the deformities caused by foot binding to the damage to internal organs caused by corsets. Here are some recent articles:
Hsieh, C.C. and D. Trichopoulos, D. Eur. J. Cancer 27:131-5 (1991) "Breast size, handedness and breast cancer risk" Premenopausal women who do not wear bras had less than half the risk of breast cancer compared with bra wearers. [The authors suggested that this might be due to braless women being thinner; however, many subsequent studies have shown that cup size is not related to breast cancer risk.] Cup size was not related to breast cancer risk in pre-menopausal women. In postmenopausal women, the slight increase risk with cup size was largely accounted for by obesity.
Singer, S. and Grismaijer, S. "Dressed to Kill: The connection between bras and breast cancer" Avery Press, 1995Institute for the Study of Culturogenic Disease, P.O. Box 1880, Pahoa, Hawaii 96778 A study of almost 5000 women, half of whom had been diagnosed with cancer. Breast cancer rates are related to the number of hours per day that women wear bras. More hours of bra wear per day had higher rates. Women who wore bras 24 hours per day had a breast cancer rate 125 times higher than braless women. More red marks and grooves left by bras were reported by women with breast cancer.
Bujan, L. and R.Mieusset, R. Contraception Fertilite Sexualite 23:611-4(1995) "Male Contraception by Testicular Heating" Holding testes close to the trunk with specific underwear was an effective form of birth control for human couples. The underwear was only worn during waking hours and it only caused a temperature rise of 1 to 2 degrees Centrigrade.
Parazzini, F. et al. Int. J. Andrology 18:137-40 (1995) About twice the rate of dyspermia was found in men who wear tight underpants. They are speaking only of commercially-available underwear and looked at loose versus tight. "Likewise, the odds ration of dyspermia was 1.6 in men reporting usually wearing tight trousers (including jeans), in comparison with those wearing loose trousers."
Shafik, A. Urological Research 21:367-70 (1993) Loosely-fitted polyester underpants on dogs caused dramatic decreases in sperm counts and an increase in degeneration of the testes. "Polyester pants had a deleterious effect on spermatogenesis in all dogs of the test group. This is evident from the defective character of the semen collected while the animals were wearing the polyester pants, as well as from the testicular biopsies." Some changes were permanent (persistence of degeneration of the seminiferous tubules). Groups of dogs with cotton pants and controls without underwear were normal.
Tanabe, N. et al. J. Dermatol. 23:648-51 (1996) "Lymphadema due to chronic penile strangulation: a case report" [penile ring led to lymphadema and nodules that had to be surgically removed]
Kochenour, N. Clinical Obst. Gynecol. 23:1045-1059 Lactation Suppression "The suppression of lactation in the postpartum period can be accomplished in approximately 60-70% of females by the use of a tight brassiere and avoidance of stimulation of the nipples."
IV. Hormone Effects
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Hormones have been related to breast cancer risk.
Birkenfeld, A. and Case, N. Obstet.-Gynecol.-Clin.-North-Am. 21:433-444 (1994) "Functional anatomy and physiology of the female breast" Oxytocin leads to contraction of myoepithelial cells and emptying of the alveolar lumen. Tactile sensors in the areola cause the hypothalamus to synthesize oxytocin.
Murrell, T.G. Breast Cancer Res. Treatment 35:225-9 (1995) "The potential for oxytocin to prevent breast cancer: a hypothesis" Regular nipple stimulation should increase oxytocin levels, prevent ductal obstruction, and help drain away carcinogens from the breast.
Murrell, T.G. Med.-Hypotheses 36:389-96 (1991) "Epidemiological and biochemical support for a theory on the cause and prevention of breast cancer" "Localized hypoxia could cause the production of superoxide free radicals, the products of which are carcinogenic. This could lead to fibroblast proliferation and breast cancer. Oxytocin from nipple stimulation would reduce hypoxia by relieving acinal gland destention. Draining the breasts of the products of superoxide free-radical release by the encouragement of regular nipple erections may prevent such breast disease." "This pathway is initiated by hypoxia of local tissue and results in free radical production." "Stimulation of the breast in non-lactating women is not thought to elevate prolactin levels, but to lower them." "Love and Rose were able to demonstrate up to 15 times the levels of prolactin in women at risk of familial breast cancer." [Breasts that are bound in a bra would get less stimulation. Braless breasts would receive plenty of stimulation from bouncing and rubbing against fabric. Nipple erections would be expected to occur more often when braless.]
Sipe, H.J. et al Carcinogenesis 15:2637-43 (1994) "...the futile metabolism of micromolar quantities of estradiol catalyzes the oxidation of much greater concentrations of biochemical reducing cofactors, such as glutathione and NADH, with hydrogen peroxide produced as a consequence. The accumulation of intracellular hydrogen peroxide could explain the hydroxyl radical-induced DNA base lesions recently reported for female breast cancer tissue."
Simpson, H.W. et al. Breast Cancer Res. Treat. 37:169-78 (1996) A natural monthly temperature cycle in the human breast. This cycle was abnormal, had less amplitude, and had a higher temp in cancerous breasts than in non-cancerous breasts. [This temperature cycling may be related to prevention or progression of disease.]
Veronesi, U. et al. Lancet 343:1545-7 (1994) Breast cancer surgery is more successful during the luteal phase of the menstrual cycle.
V. Oxidative Stress, Hypoxia, Glutathione
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Local hypoxia (lack of normal oxygen levels) can happen when circulation is compromised (as in a heart attack or stroke). Hypoxia can reduce the effectiveness of cellular antioxidant mechanisms and has been related to altered gene expression and DNA damage.
Chen, J. et al Int. J. Epidemiol. 21:625-35 (1992) "Plasma levels of dietary antioxidants are consistently negatively correlated with cancer mortality rates."
Reed, D.J. and Savage, M.K. in K.J.A. Davies and F. Ursini (eds.) The Oxygen Paradox, Cleup Univ. Press, Padova, Italy, 1995 Normal metabolism in cells produces extremely toxic compounds that must be dealt with. If detoxification does not keep pace, chain reactions can lead to cell death. "Without mitochondrial antioxidant defense systems such as the glutathione redox cycle, aerobic metabolism, an essential process for life in many species, would likely be impossible due to the endogenous formation of reactive oxygen species (ROS)." "Detoxification of endogenously produced hydrogen peroxide is critical for redox maintenance of mitochondrial as well as cellular homeostasis.:
Rupec, R.A. and Baeuerle, P.A. European J. Biochem. 234:632-640 (1995) "In tumors, hypoxia and oxidative stress are regarded as triggers for enhanced proliferation and metastasis. Hypoxia and reoxygenation exert part of their biological effects by inducing the expression of novel genes..."
Reynolds, T.Y. et al. Cancer Research Dec.15, 1996 Hypoxia in tumors causes an increase in mutation rates. This explains why tumors tend to become more malignant with time. The hypoxic environment may damage DNA directly or there may be a secondary mechanism, such as increased acidity.
Malins, D.C. et al. Proceedings of the National Academy of Sciences-USA 93:2557-63 (1996) "Progression of human breast cancers to the metastatic state is linked to hydroxyl radical- induced DNA damage." Metastatic breast tumors had twice the hydroxyl radical DNA damage of non-metastatic tumors.
J.Clinical Nutrition 48:575-86 (1994) "Diet and oxidative stress in breast, colon, and prostate cancer."
Am. J. Kidney Dis. 22:308-13 (1993) "Evidence for increased cancer deaths in chronic dialysis patients."
Perry, R.R. et al. Cancer 72:783-7 (1993) GSH levels were higher in breast tumors and affected lymph nodes. "GSH appears to be a marker of breast malignancy that is independent of hormonal receptor status and stage...." GSH levels varied over 11-fold in various areas of the same breast tumor.
Reed, D.J. review article, source not known,-- "The toxicity of oxygen even during normal environmental conditions requires constant cellular resources to detoxify toxic oxygen metabolites, including superoxide radicals and hydrogen peroxide. Failure to provide or maintain the cellular protective systems is now known to cause serious human diseases that can be greatly exacerbated by exposures to toxic chemicals." Superoxide and hydrogen peroxide, if not reduced, can cause the formation of lipid hydroperoxides and damage to membranes, nucleic acids, proteins and their functions.
VI. Cup Size, Obesity
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Some people might think that women who do not wear bras would be smaller breasted and therefore have lower cancer rates because of size. However, cup size has been shown to not be significant.
Frankest, S. et al. Int. J. Cancer 67:181-6 (1996) Cup size is not related to breast cancer risk. "Bra cup size and weight in adolescence and in young adulthood did not exert a significant or consistent influence on breast cancer risk. The apparent relationship with body mass index at middle age and weight gain between age 30 years and diagnosis was eliminated by allowance for body mass index at diagnosis."
Gateley, C.A. et al. Eur. J. Cancer 28:125-7 (1992) The occurrence of breast cysts was correlated with a small bra and bra cup size.
Wynder , E.L. et al. Cancer 13, 559-601 (1960) Cup size not related to breast cancer risk.
Soini, I. Int. J. Epidemiol. 6, 365-73 (1977) Cup size not related to breast cancer risk.
Hirohata, T. et al. Br. Med. J. 2, 641 (1977) Cup size not related to breast cancer risk.
Katariya R.N. et al. Br. J. Cancer 29, 270-73 (1974) Breast volumes in cancer of the breast. Mammogram studies showed that cup size was not related to breast cancer risk.
VII. References on breast ligament atrophy
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The myth that bras prevent the breast ptosis (sagging) has no scientific support. Medical research actually shows that weight-bearing and movement is necessary to the maintainence of healthy ligaments. And, ligaments are responsible for supporting and giving shape to the breasts:
J.G. Gamble et al. Am J. Sports Med. vol. 12, 22-28 (1984). "Like muscle and bone, ligaments are dynamic, undergoing hypertrophy with excercise and atrophy with immobilization." Ligaments are a composite of fibroblasts and collagen in a proteoglycan matrix. Immobilization of knee joints in rabbits caused changes after 2 weeks. "The cells switch from an anabolic synthetic state to a catabolic, degradative state during immobility." Enzymes that degrade a tissue component increased in activity. [ This article shows that ligaments need to have movement in order to keep from atrophy (getting thinner and weaker). This suggests that if you immobilize a bodily part, such as knee or a breast, that the ligaments will get thinner & weaker, because they will switch to a degradative state. Ligaments are largely responsible for holding the shape of the breast. ]
S. Bayati and B.R. Seckel Plast. Reconstr. Surg. vol.9, 501 (1995) "The horizontal position of this ligament determines the medial versus lateral fall of the ptotic breast." (Ligaments support the breast and determine how they sag.)
F.L. Harwood and D. Amiel J. Appl. PHysiol. vol. 72, 1687-91 (1992) Ligamentous tissues are susceptible to the effects of stress deprivation. "After 12 weeks (of immobilization), all three tissues experienced significant losses of collagen mass, which resulted in tissue atrophy." Both ligaments and tendons experienced atrophy. [ Ligaments need to be under some amount of stress (weight-bearing), in order to keep their strength. ]
W.H. Akeson et al. Clin. Orthop. vol 219, 28 (1987) "Stress deprivation alters the morphologic, biochemical and biomechanical characteristics of various components of synovial joints." Weakening of ligament insertion sites and disorganization of cellular and fibrallar ligament alignment were found. Collagen decreased 10%; atrophy of cartilage was seen. "Reduced load-to-failure and reduced energy-absorbing capacity of the bone-ligament complex progresses to about 1/3 that of controls." [ Stress-deprived ligaments become less strong and more likely to stretch and break under a load. ]
D. Amiel et al. Clin. Orthop. vol.172, 265 (1983) "Immobilization causes atrophy with reduction of collagen mass and increased collagen degradation. The matrix composition, as reflected by collagen turnover, changed dramaticallly as the period of immobilization was increassed from 9 to 12 weeks. A large decrease in total collagen mass (-27%) is observed at the end of 12 weeks. Exponential degradation has occurred as immobilization has continued, and ligament regenerative capacity apparently has failed."
L. Klein et al. J. Bone Joint Surg. vol 64, 225 (1982) Isotopic evidence for resorption of soft tissues and bone in immobilized dogs. "We have demonstrated significant atrophy of soft tissue (lateral meniscus and ant. curc. ligament) as well as of bone in immobilized joints of dogs."
L. Klein et al. J. Orthop. Res. vol. 7, 80 (1989) Prevention of ligament and meniscus atrophy by active joint motion in a non-weight bearing model. Models of immobilization have shown that resorption of isotope and atrophy of mass occurred for hard tissue (bone) and soft tissues (ligament, tendon, and meniscus). In dogs, this model showed bone loss, but the active joint motion protected ligaments and tendons.
P. Diekstall et al. Sportverlitz Sportchaden, vol 9, 35-43 (Jun 95). Prolonged immobilization can threaten the surgical results. The reduction in muscle diameter is reported to be 10 to 60 % after 4 weeks of immobilization depending on the different muscle groups. The result of immobilization is shortening of all fibrous tissues. The loss of ligament-specific orientation of fibrils leads to significant reduction in tensile strength.
VIII. Miscellaneous
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Mary Wolff et al. Ann. Rev. Pharmacol. Toxicol. 36: 573-96 (1996) "Breast Cancer and Environmnetal Risk Factors" p.576 "Mammary gland susceptibility to radiation-induced breast cancer thus appears to be related to stages of breast development. Susceptibility during various time periods in a woman's life may be related to the extent of breast cell proliferation and hormonal status at the time radiation damage occurs." [nulliparous women might have much higher rates of mammogram- induced breast cancer] "Because relatively little is known about breast cancer causation, it is important to increase efforts for determining the contributions of chemical exposures and physical agents to the development of this disease."
Snedeker, S.M. and Diaugustine, R.P. Prog.-Clin.-Biol.-Res. 394:211-53 (1996) "Animal studies indicate that there are critical periods of susceptibility to chemical carcinogens, since the number and malignancy of tumors are increased when carcinogens are administered to young virgin animals during the proliferative period of ductal morphogenesis."
Clark, R.M. et al. J.Natl. Cancer Inst. 84:683-9 (1992) "Breast irradiation significantly reduces breast (tumor) relapse, but it does not influence survival.
Law, J. British Journal of Radiology 66:691-8 (1993) "Variations in individual radiation dose in a breast screening programme and consequences for the balance between associated risk and benefit."
Crowell, E.B. W.Virginia Medical Journal 89:448-51 (1993) "Breast Cancer -- A Medical Disease?" "It is now believed that breast cancer usually spreads early and that removal of neither lymph nodes nor the breast prolongs survival."
Tokunaga, M. et al. Cancer 72:1657-65 (1993) "The risk of female breast cancer in association with radiation dose is well established, on the basis of follow-up studies of the atomic bomb survivors and other exposed populations." "...especially strong for women exposed before 20 years of age." "Prevalence of proliferative disease in general and atypical hyperplasia in particular were positively associated with radiation dose. The associations were strongest for subjects who were between 40 and 49 years of age at the time of the bombing."
Pelton, R., Pelton, T.C. and Vinton, V.C. (M.D.) "How to Prevent Breast Cancer" Fireside Books , 1995. This book is a "lifestyle guide for the prevention of breast cancer and its recurrence, with an investigation of the critical risk factors" Chapter 22 gives a discussion of the lymphatic system and the positive effects of non-sexual breast massage.
Proctor, Robert N. "Cancer Wars" published by BasicBooks (HarperCollins Publishers), 1995. How politics shapes what we know and don't know about cancer.
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