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Breast cancer chemotherapy and cognitive impairment
Los Angeles, CA. The authors of this paper introduce their study by pointing out that cognitive complaints among women who have received chemotherapy as part of the primary treatment for breast cancer are appearing with “concerning frequency.” Of eight recently published studies involving breast cancer survivors undergoing cognitive performance assessment, half have found memory to be particularly affected. This study from the University of California at Los Angeles and the VA Healthcare System of Los Angeles used positron emission tomography to compare control subjects with women having received chemotherapy. Subjects were scanned while performing control and memory related tasks in order to evaluate cognition-related cerebral flood flow. Specific alterations in activity were found for the frontal cortex, cerebellum and basal ganglia in breast cancer survivors by this approach to functional neuroimaging 5-10 years after the subjects had completed chemotherapy.
Silverman, D. H. S. et al. Altered Frontocortical, Cerebellar and Basal Ganglia Activity in Adjuvant-treated Breast Cancer Survivors 5-10 years after Chemotherapy. Breast Cancer Research and Treatment, 2006. Published electronically ahead of print.
Dangers of radiation therapy for breast cancer
BETHESDA, MD. It is well known that radiation is implicated in the process of carcinogenesis. An increase of breast cancer has been linked to ionizing radiation used for treatment of non-malignant and malignant diseases and in addition, excess cancers were documented among atomic bomb survivors. Thus an interesting question involves what if any risk of new primary cancers might be due to the therapeutic use of radiation along with surgery for breast cancer. A very large study has been recently reported in a document from the National Cancer Institute (in press) which is based on a huge database known as Surveillance Epidemiology and End Results (SEER), which in the case of this study covered the period from 1973 to 2000 with follow-up on over 300,000 women. Increased cancer rates for women having had radiation as part of their initial treatment were calculated by comparing with rates observed for non-irradiated patients. For those surviving 5-10 years, risk of cancer of the esophagus was increased 3-fold, bone 6-fold, and soft tissue 3-fold. For angio-sarcoma the ratio of observed to expected cases was over 17 and there was a correlation between the side irradiated and the location of the soft tissue sarcomas. This same correlation was observed with lung cancer where the 10-year relative risk was about 1.5. These increased risks were in general consistent with those observed in smaller studies. The authors do not discuss the risk-benefit aspect issue raised by this study.
Curtis, R. E. et al. New Malignancies among Cancer Survivors: SEER Cancer Registries, 1973-2000. NCI Publication # 05-5302, Chapter 7. (Free download available—“Google” NIH Publication 05-5302, identify the document and click “PDF available”)
Breast cancer – The importance of a second opinion
ANN ARBOR, MI. Breast cancer can present a diagnostic challenge, especially regarding such issues as the extent and histological nature of the disease. This in turn impacts management recommendations. In many cases, the initial diagnosis will not originate at a multidisciplinary breast cancer clinic. This study reviewed the medical records of 149 consecutive (to avoid bias) patients referred to such a clinic over a 1-year period. The records were reviewed retrospectively for changes in radiologic, pathologic, surgical and medical interpretations and the effect of these alterations on recommended surgical management was examined. The review of imaging studies resulted in changes in interpretations in 45% of patients studied, and this resulted in changes in surgical management in 11% of patients. Pathological reinterpretation resulted in 9% of patients having changes made in recommended surgical management, and for 34% of the patients, changes in surgical management resulted only from the multidisciplinary discussion with the surgeons, medical oncologists and radiation oncologists. Six patients were actually downgraded to benign disease. In all, approximately half the patients had a change in management as the result of this second opinion from a multidisciplinary center and for 32% of the women, the changes were based not on a disagreement about the radiology or pathology findings but rather on a different view of what constitutes the standard of care.
Newman, E.A. et al. Changes in Surgical Management Resulting from Case Review at Breast Cancer Multidisciplinary Tumor Board. Cancer, 2006, Vol. 107, pp. 2364-51.
NEWSBRIEF -
Olive oil helps combat breast cancer. There is ample evidence that the diet consumed
in Mediterranean countries helps protect women against breast cancer. Now Professor Javier Menendez
and his team at Northwestern University in Chicago suggest that olive oil may be the main protector. Dr.
Menendez found that oleic acid, the major fatty acid in olive oil, is highly effective in killing the Her2/neu
protein, a major factor in the growth of breast cancer tumours. The oil is, as a matter of fact, just as effective
as the anticancer drug Herceptin and, when combined with this drug, results in a reduction of 70% in
Her2/neu levels (in test tube experiments). Dr. Menendez suggests that olive oil manufacturers should
begin to list the total oleic acid content on their products so that consumers can select the best brand for
cancer prevention.
New Scientist, January 15, 2005, p. 7
Mastectomy versus lumpectomy – No survival difference
WASHINGTON, DC. There are two major alternatives for the surgical treatment of breast cancer. One,
mastectomy, involves removal of the entire involved breast while the other, breast conservation therapy
(BCT), involves removing just the tumour (lumpectomy) and subsequent radiation therapy. If the lymph
nodes in the armpits (axillary lymph nodes) are found to be affected they are usually removed as well.
Researchers at the National Cancer Institute undertook a study between 1979 and 1987 to evaluate the
survival rate of women who had undergone mastectomy as compared to women who had been treated
with BCT. The 237 study participants have now been followed up for a median of 18.4 years. The
survival rate for mastectomy patients over this period was 58% versus 54% in the BCT group – a
difference that was not statistically significant. The disease-free survival rate was 67% for the
mastectomy group and 63% for the BCT group – again a difference that was not statistically significant.
There was no statistically significant difference in the number of women who developed cancer in the
previously unaffected breast (7 in the mastectomy group and 5 in the BCT group). There was also no
difference in the number of women who developed cancer at sites other than the breast (10 in each
group).
The researchers conclude that there are no statistically significant differences in the survival rate or in the
incidence of the development of new cancers between women treated with mastectomy and those treated
with breast conservation therapy.
Poggi, MM, et al. Eighteen-year results in the treatment of early breast carcinoma with mastectomy versus breast
conservation therapy. Cancer, Vol. 98, August 15, 2003, pp. 697-702
Curcumin and chemotherapy
CHAPEL HILL, NORTH CAROLINA. There is growing evidence that curcumin, a component of the spice
turmeric, may be effective in the prevention of breast, prostate, colon, and oral cancers. Extracts
containing curcumin have been used in India for generations in the treatment of inflammation, skin
wounds, liver and gallbladder disorders, and persistent coughs. It is estimated that the average dietary
intake of curcumin in India and certain parts of Southeast Asia is 200 mg/day or more.
Curcumin is a highly effective scavenger of reactive oxygen species (ROS) and also inhibits the JNK (c-
Jun NH2-terminal kinase) pathway. Both ROS and an activated JNK pathway are crucial elements in
successful chemotherapy. Researchers at the University of North Carolina now report that curcumin may
interfere with the action of several chemotherapy drugs used in the treatment of breast cancer. Culture
experiments showed that curcumin inhibited the cancer cell destroying capability of several chemotherapy
drugs (mechlorethamine, Adriamycin, and camptothecin) by as much as 70%. The results were
confirmed in experiments with laboratory mice. It is believed that curcumin exhibits its effect through ROS
scavenging and inhibition of the JNK pathway.
The researchers conclude that more research is urgently needed to establish whether breast cancer
patients undergoing chemotherapy should be told to limit their intake of curcumin and turmeric
extracts.
Somasundaram, S., et al. Dietary curcumin inhibits chemotherapy-induced apoptosis in models of human
breast cancer. Cancer Research, Vol. 62, July 1, 2002, pp. 3868-75
Hot chemotherapy Encasing chemotherapy drugs in liposomes (hydrated phospholipid
globules) before injecting them is becoming increasingly popular as it encourages the drugs to enter only
cancer cells and leave healthy ones alone. Researchers at the Duke Cancer Center in North Carolina
have found that heating up the tumours with microwaves or hot water (in the case of breast cancer) while
injecting the liposomes make them far more effective. In a trial involving 21 women with breast cancer
the researchers found that a combination of heat and chemo drug/liposomes shrank or completely
destroyed all 21 tumours involved. Other medical centers have had equally encouraging results and work
is now underway to test the technique on prostate cancer.
New Scientist, May 25, 2002, p. 13
Tamoxifen and endometrial cancer
AMSTERDAM, THE NETHERLANDS. Tamoxifen therapy has long been used in the treatment of
metastatic breast cancer and in the prevention of recurrence of breast cancer. It is known that tamoxifen
increases the risk of developing endometrial cancer, but so far it has been assumed that this "side effect"
was of relatively little importance. Now researchers at the Netherlands Cancer Institute question this
assumption. Their study involved 299 women who had developed endometrial cancer subsequent to
being diagnosed with breast cancer and 860 matched controls who had been diagnosed with breast
cancer, but had not developed endometrial cancer.
The researchers found that 36.1 per cent of the women with endometrial cancer had used tamoxifen as
compared to 28.5 per cent in the control group. This translates into a 50 per cent greater risk among
tamoxifen users. The risk increased with duration of use and was almost seven times higher for women
who had taken tamoxifen for at least five years when compared to the controls. The severity of the
cancer and the presence of sarcomas were also much higher among long-term users. The three-year
endometrial-cancer-specific survival was 76 per cent for long-term tamoxifen users versus 94 per cent for
non-users. The researchers calculate that 20 excess cases of endometrial cancer would develop in 1000
tamoxifen users followed up for 10 years.
They conclude that the benefits of tamoxifen therapy still outweigh the risks in the treatment of metastatic
breast cancer and in prevention of contralateral cancer. However, they seriously question widespread
use of tamoxifen as a preventive agent against breast cancer in healthy women.
Bergman, Liesbeth, et al. Risk and prognosis of endometrial cancer after tamoxifen for breast cancer.
The Lancet, Vol. 356, September 9, 2000, pp. 881-87
Gelmon, Karen. One step forward or one step back with tamoxifen? The Lancet, Vol. 356, September 9,
2000, pp. 868-69 (commentary)
Breast cancer surgery revisited
AMSTERDAM, THE NETHERLANDS. Breast conserving therapy (lumpectomy followed by radiation) has
been shown to be as effective as mastectomy (removal of entire breast) in the treatment of breast tumors
with a diameter of 2 cm or less. A team of medical researchers from Belgium, the Netherlands, South
Africa, and the UK now report that breast conserving therapy (BCT) results in similar survival rates as
mastectomy when dealing with larger tumors (2.1-5 cm) as well. Their study involved 868 women with
stage II breast cancer who were randomly assigned to receive either BCT or radical mastectomy. After
10 years of follow-up there was no significant difference in the rate of survival among the BCT patients
(65 per cent) and the mastectomy patients (66 per cent). The incidence of distant metastasis was also
similar in the two groups over the 10-year follow-up period; 39 per cent for the BCT patients and 34 per
cent of the mastectomy patients. There was, however, a significant difference in the recurrence of local
tumors among the two groups. Among the BCT patients six per cent had a recurrence as compared to
only 3.3 per cent in the mastectomy group. The 13-year survival rates were 60 per cent in the
mastectomy group and 55 per cent in the BCT group. The researchers conclude that BCT and radical
mastectomy result in similar survival rates among patients with stage II breast cancer.
van Dongen, Joop A., et al. Long-term results of a randomized trial comparing breast-conserving therapy
with mastectomy: European Organization for Research and Treatment of Cancer 10801 trial. Journal of
the National Cancer Institute, Vol. 92, July 19, 2000, pp. 1143-50
Tamoxifen may induce asthma attacks
DUNDEE, UNITED KINGDOM. Doctors at the Kings Cross Hospital warn that
asthmatic women being treated for breast cancer with tamoxifen may aggravate
their asthma. They describe the case of a 53-year old woman who had suffered
from asthma for over 20 years. She was able to control her attacks with
salbutamol. In 1990 she underwent surgery for breast cancer and was started
on tamoxifen. Her asthma control subsequently deteriorated particularly a
few hours after taking the tamoxifen. The doctors caution against
prescribing tamoxifen to asthma sufferers without adequate
precautions.
Smith, R.P., et al. Tamoxifen-induced asthma. The Lancet, Vol. 341, March
20, 1993, p. 772
Tamoxifen increases the risk of endometrial cancer
AMSTERDAM, NETHERLANDS. Researchers at the Dutch Cancer Institute have
concluded that women who are given tamoxifen as part of their breast cancer
therapy have a slightly increased risk (1.3 fold) of developing cancer of the
endometrium. The risk increases markedly with the duration of the treatment;
thus breast cancer patients who received 30 or 40 mg per day of tamoxifen for
more than two years were found to have a 2.3 fold greater risk of developing
endometrial cancer than did patients who had never received tamoxifen. The
study involved a total of 383 breast cancer patients, 98 of which had
developed endometrial cancer at least three months after the diagnosis of
primary breast cancer. The researchers emphasize that the benefits of using
tamoxifen in breast cancer therapy clearly outweighs the risk of developing
endometrial cancer. However, they do question the wisdom of prescribing
tamoxifen to healthy women in order to possibly reduce their future risk of
developing breast cancer.
van Leeuwen, Flora E., et al. Risk of endometrial cancer after tamoxifen
treatment of breast cancer. The Lancet, Vol. 343, February 19, 1994, pp.
448-52
Tamoxifen trial halted
PITTSBURG, PENNSYLVANIA. The National Cancer Institute has suspended a large
scale study aimed at determining if tamoxifen will prevent breast cancer in
women at special risk. The study which was started in 1992 was to involve
16,000 healthy women. Half would be given tamoxifen for five years, the
other half, a placebo. All participants would be followed for seven years.
The Cancer Institute halted the study when it found out that its leader, a
renowned surgeon and cancer researcher, had been involved in another trial in
which data had been falsified and suppressed. The falsified data occurred in
a smaller trial of tamoxifen involving about 3,000 women with breast cancer.
The researchers found that the rate of fatal endometrial cancer was much
higher among the women taking tamoxifen than in the general population. They
delayed the publication of the data and continued to sign up people for the
large scale trial on healthy women without informing them of the danger. A
congressional hearing is now underway to determine if the tamoxifen study
should be permanently cancelled.
Marshall, Eliot. Tamoxifen: Hanging in the balance. Science, Vol. 264, June
10, 1994, pp. 1524-27
Breast-sparing surgery is as effective as mastectomy
BETHESDA, MARYLAND. The National Cancer Institute has just released a major
study comparing the survival rates of breast cancer patients who had been
treated with breast-sparing surgery (lumpectomy) and patients who had had a
full mastectomy (removal of entire breast, lymph nodes in the armpit and part
of the upper chest muscle). The researchers studied the outcome of almost
4,000 cancer operations and found that the survival rate amongst women who
had undergone breast-sparing surgery followed by radiation treatment was
equivalent to the survival rate of women who had had a full mastectomy. The
researchers conclude that "Breast conservation treatment is an appropriate
method of primary therapy for the majority of women with stage I and II
breast cancer and is preferable because it provides survival equivalent to
total mastectomy and axillary dissection while preserving the breast."
Abrams, Jeffrey, et al. Survival after breast-sparing surgery versus
mastectomy. Journal of the National Cancer Institute, Vol. 86, No. 22,
November 16, 1994, pp. 1672-73
Timing of breast cancer surgery is important
MILAN, ITALY. Scientists at the Italian National Cancer Institute have
confirmed that the timing of breast cancer surgery in relation to the
menstrual cycle is an important factor in preventing relapse. The
researchers studied 1175 premenopausal women who had been diagnosed with
breast cancer involving the axillary (armpit) lymph nodes. They found that
36.6 per cent of the women who had their surgery in the first half of their
menstrual cycle (days 0-14) had a recurrence of their disease within five
years. The recurrence rate was particularly high if surgery was performed
immediately before ovulation (days 12-14). In contrast, women who had
surgery during the latter phase of their menstrual cycle had a relapse rate
of only 29.6 per cent. The researchers recommend that breast cancer surgery
on premenopausal women be performed in the latter part of the cycle when
axillary lymph node removal is involved.
Veronesi, Umberto, et al. Effect of menstrual phase on surgical treatment of
breast cancer. The Lancet, Vol. 343, June 18, 1994, pp. 1545-47
Fentiman, Ian S., et al. Effect of menstrual phase on surgical treatment of
breast cancer (letters to the editor). The Lancet, Vol. 344, August 6, 1994,
pp. 402-04
Alpha-linolenic acid prevents breast cancer from spreading
TOURS, FRANCE. Medical doctors at the University Hospital in Tours have
discovered that breast cancer victims who have a high content of alpha-
linolenic acid (9,12,15-octadecatrienoic acid) in their breast tissue are
less likely to develop metastases (cancer in distant organs such as the
stomach, intestines, etc.). The study involved 121 women who had been
diagnosed with localised breast cancer. The researchers analyzed samples of
adipose (fatty) tissue taken close to the tumor at the time of surgery. They
found that the cancer was more likely to have spread to the lymph nodes in
the armpits in women with a low level of alpha-linolenic acid in their
tissue. They found no relationship between alpha-linolenic acid content and
tumor size. After an average follow up of 31 months, 21 of the women
developed metastases. The researchers discovered that women who had a high
adipose tissue content of alpha-linolenic acid at the time of surgery were
five times less likely to have developed metastases than did women with a low
content (less than 0.38 per cent). Original tumor size was also an important
factor in predicting risk of metastasis which is the main cause of death
among breast cancer patients. Women who had a tumor with a diameter greater
than 5 cm had a 4.7 times greater risk of developing metastases than did
women with smaller tumors. The researchers conclude that dietary
supplementation with alpha-linolenic acid might delay or prevent the
development of metastases in breast cancer patients. They also point out
that previous research has shown that a high intake of dietary fat
originating from fish helps prevent breast cancer in the first place and also
improves survival among breast cancer patients. NOTE: Flax oil, pumpkin oil
and purslane are good sources of alpha-linolenic acid.
Bougnoux, P., et al. Alpha-linolenic acid content of adipose breast tissue:
a host determinant of the risk of early metastasis in breast cancer. British
Journal of Cancer, Vol. 70, No. 2, August 1994, pp. 330-34
Diet is important for breast cancer survival
TORONTO, CANADA. Researchers at the National Cancer Institute of Canada have
found that diet and vitamin intake are important factors in determining
survival from breast cancer. Their study involved 678 women who were
diagnosed with breast cancer between January 1982 and June 1992. Seventy-six
of the women died from the cancer during the review period. After studying
the dietary habits of the women prior to their cancer diagnosis, the
researchers concluded that the risk of dying from breast cancer increases by
50 per cent for every 5 per cent (per cent of energy) increase in the intake
of saturated fat. They also found that women who had a relatively high
intake of beta-carotene (greater than 7690 IU/day) had half the risk of dying
from breast cancer than did women with a low intake (less than 3607 IU/day).
Vitamin C was also found to be protective. Women consuming more than 210
mg/day had a 57 per cent lower risk of dying from breast cancer than women
getting less than 110 mg/day. Vitamin E also showed a slight protective
effect despite the fact that the amounts consumed by the women were very
small, ie. 24 IU per day or less.
Jain, Meera, et al. Premorbid diet and the prognosis of women with breast
cancer. Journal of the National Cancer Institute, Vol. 86, No. 18, September
21, 1994, pp. 1390-97
Mind-body connection gains acceptance
BETHESDA, MARYLAND. The effects of relaxation therapy and visualization on
the immune system were the subject of a recent symposium sponsored by the
National Institutes of Health. Dr. Mary Banks Jasnoski of the George
Washington University reported that relaxing and imagining a powerful immune
system can actually increase T-cell levels in people who are able to
concentrate intently and who respond intensively to experiences and
imagination. Dr. David Spiegel of Stanford University reported that women
with metastatic breast cancer who participated in group therapy as part of
their treatment survived twice as long as women who received medical
treatment but no group therapy. Dr. Fawzy Fawzy of the University of
California reported on a study he had done to evaluate the effect of
psychological treatment on melanoma patients. The patients who all had had
surgery for stage I melanoma were split into two groups. One group had a
weekly 90-minute session of psychological treatment while the other group
received no psychological support. The patients in the treatment group had
half the rate of recurrence as the control group and about a third fewer
deaths over five to six years. Work is now going on at Temple University to
determine what psychological, social, and neuroendocrine factors are
responsible in the development or avoidance of cervical cancer.
Flach, Jennifer and Seachrist, Lisa. Mind-body meld may boost immunity.
Journal of the National Cancer Institute, Vol. 86, No. 4, February 16, 1994,
pp. 256-58
Estrogen therapy may promote metastatic breast cancer
ROCHESTER, MINNESOTA. The administration of estrogen in low doses is
believed to stimulate the growth of breast cancer cells. For this reason
most doctors do not recommend estrogen replacement therapy for women with a
history of breast cancer. Researchers at the Mayo Clinic now report that
withdrawal of estrogen replacement therapy in postmenopausal women with
metastatic breast cancer can lead to a regression of the cancer. Their study
involved four postmenopausal women, three of whom had previously been
diagnosed with breast cancer and operated upon. All four women were on
estrogen replacement therapy to alleviate menopausal symptoms when they
developed cancer in the bones or lungs. The reseachers stopped the estrogen
therapy when the metastatic cancers were discovered and the cancers then
regressed to the point where they almost disappeared; the improvement lasted
for two to three years. The researchers recommend that estrogen withdrawal
be the first treatment option for women who develop metastatic breast cancer
while on estrogen replacement therapy.
Dhodapkar, Madhav V., et al. Estrogen replacement therapy withdrawal and
regression of metastatic breast cancer. Cancer, Vol. 75, No. 1, January 1,
1995, pp. 43-46
Acceptance of lumpectomy growing
BETHESDA, MARYLAND. Radical mastectomy (removal of entire breast and lymph
nodes) has long been the method perferred by surgeons in the treatment of
breast cancer. This is now changing. Between 1983 and 1991 the use of
lumpectomy (removal of tumor only) in breast cancer surgery rose from 16 per
cent to 37 per cent while the use of radical mastectomy decreased from 75 per
cent to 58 per cent. The preferential use of lumpectomy in in situ and in
stage I cancers has grown even more pronounced. More than 50 per cent of all
in situ cancers and slightly less than 50 per cent of all stage I cancers
were treated with lumpectomy in 1991.
Ries, Lynn. Use of lumpectomy for breast cancer. Journal of the National
Cancer Institute, Vol. 87, No. 5, March 1, 1995, p. 339
Melatonin blocks the growth of breast cancer cells
TUCSON, ARIZONA. A team of American and French researchers report some
exciting developments concerning the ability of melatonin to retard the
growth of breast cancer. Melatonin has previously been found to block the
tumor-promoting effects of the hormone estradiol. Now it appears that
melatonin also inhibits the tumor-promoter prolactin. The researchers
carried out an experiment using human breast cancer cells grown in
vitro. Human prolactin was found to increase the growth of the cancer
cells by a factor of two. Melatonin completely inhibited the effects of
prolactin although it had no effect on the growth rate of the cancer in the
absence of prolactin. The tumor-promoting effects of human growth hormone
was also found to be inhibited by melatonin. It is of significant interest
that the greatest benefit of melatonin was found at levels equal to those
normally found in the blood during the night. Higher concentrations of
melatonin proved completely ineffective in inhibiting the prolactin-
stimulated tumor growth. The researchers speculate that the normal nighttime
secretion of melatonin is part of a natural mechanism which suppresses the
growth of breast cells including cancerous ones. (NOTE: A completely dark
bedroom is required for optimum secretion of melatonin).
Lemus-Wilson, A., et al. Melatonin blocks the stimulatory effects of
prolactin on human breast cancer cell growth in culture. British Journal of
Cancer, Vol. 72, No. 6, December 1995, pp. 1435-40
Tamoxifen trial halted
BETHESDA, MARYLAND. The National Cancer Institute has advised physicians to
limit tamoxifen use to a maximum of five years for women with node-negative
(non-involvement of lymph glands), estrogen-receptive breast cancers who have
had lumpectomy and radiation treatment or mastectomy. The announcement
follows the termination in November 1995 of the National Surgical Adjuvant
Breast and Bowel Project's study of long-term use of tamoxifen. The project
concluded that there are no additional benefits for women taking the drug for
more than five years.
NSABP halts B-14 trial: no benefit seen beyond 5 years of tamoxifen use.
Journal of the National Cancer Institute, Vol. 87, No. 24, December 20, 1995,
p. 1829
Breast cancer overdiagnosed and overtreated
SAN FRANCISCO, CALIFORNIA. Ductal carcinoma in situ (DCIS) of the breast is
a fairly common non-invasive form of breast cancer. Most cases of DCIS are
detected through the use of mammography. It is estimated that DCIS accounts
for about 30 to 40 per cent of all mammographically detected breast cancers
and constitutes about 12 per cent of all diagnosed breast cancers in the
United States. Almost all cases of DCIS are treated with some form of
disfiguring surgery - this despite the fact that it is unknown whether the
detection and treatment of DCIS actually extend the lives of the patients.
The number of detected and surgically treated DCISs has risen astronomically
since the introduction of screening mammography. Between 1973 and 1983 the
age-adjusted rate for DCIS rose by 53 per cent in the United States.
Following the introduction of mammographic screening in 1983, the incidence
of DCIS increased by 328 per cent in the period between 1983 and 1992. It is
estimated that at least 200 per cent of this 328 per cent increase is due to
the use of mammography. The increase in diagnosed DCIS has been particularly
high in women under 50 years of age where the growth in annual incidence rate
was about 4,000 per cent greater for the period 1983-1992 than for the period
1973-1983.
In 1992, about 44 per cent of all cases of DCIS were treated with mastectomy
(removal of entire breast), 23 per cent were treated with lumpectomy (removal
of affected area only) plus radiation, 30 per cent were treated with
lumpectomy alone, and about 3 per cent were not surgically treated at all.
Survival rates during the first one to nine years were generally 100 per cent
irrespective of type of treatment. The use of mastectomy was found to vary
widely by geographical area from 28.8 per cent in Connecticut to almost 60
per cent in New Mexico. The authors of the recent report from the University
of California express serious concerns about the increasing number of DCIS
cases being detected through screening mammography especially since almost
all of these cases are treated with disfiguring surgery. The concern is
particularly acute in the case of younger women (30 to 39 years of age) where
92 per cent of all cancers detected by mammography are classified as DCIS.
The authors conclude that there is an urgent need to study the
appropriateness of the various treatment options from mastectomy to watchful
waiting.
Ernster, Virginia L., et al. Incidence of and treatment for ductal carcinoma
in situ of the breast. Journal of the American Medical Association, Vol.
275, No. 12, March 27, 1996, pp. 913-18
Page, David L. and Jensen, Roy A. Ductal carcinoma in situ of the breast.
Journal of the American Medical Association, Vol. 275, No. 12, March 27,
1996, pp. 948-49
Timing critical in breast cancer surgery
LONDON, ENGLAND. Recent research has shown that the timing of breast cancer
surgery is critical. Women who have surgery during the latter part of their
menstrual cycle have a significantly better survival rate than do women who
undergo surgery early in the cycle. Patients who are operated upon during
the first 3 to 12 days of the cycle have the poorest survival while patients
who have surgery between days 18 and 20 have the best survival rate. Now
researchers at Guy's Hospital have found that blood serum levels of
progesterone is an excellent indicator of the optimum time for surgery. A
study of 289 premenopausal women who underwent mastectomy or lumpectomy
showed that women whose progesterone level was higher than 4 nanograms/mL had
a 76 per cent better survival rate (up to 18 years of follow-up) than did
women with a progesterone level of less than 4 nanograms/mL. (Note:
Progesterone levels rise as the menstrual cycle progresses and are highest in
the luteal phase). Operating when progesterone levels are high is
particularly important in cases where the lymph nodes are involved in the
cancer. Here the survival rate was twice as good for women who had surgery
when their progesterone levels were greater than 4 nanograms/mL.
Mohr, P.E., et al. Serum progesterone and prognosis in operable breast
cancer. British Journal of Cancer, Vol. 73, No. 12, June 1996, pp. 1552-
55
Vitamin E succinate kills breast cancer cells
FREDERICK, MARYLAND. Several fat-soluble vitamins, namely vitamins A, D, E
and K, have been found to inhibit the growth of cancer tumors. Now
researchers at the National Cancer Institute report that vitamin E succinate
(d-alpha-tocopherol succinate) actually kills certain types of human breast
cancer cells in vitro. Their experiment involved two breast cancer cell
lines (MDA-MB-231 and SKBR-3) which do not respond to antiestrogen therapy.
The researchers found that vitamin E succinate (VES) inhibited the growth of
the two cell lines in a dose-dependent manner. At VES concentrations of 5,
10 and 20 micrograms/mL the number of MDA-MB-231 cells decreased by 24, 67
and 85 per cent respectively after 48 hours. Similar results were obtained
for the SKBR-3 culture. The researchers conclude that VES induces apoptosis
(programmed cell death) through activation of a specific cell surface protein
(Fas) rather than through any antioxidant or prooxidant effect. The
researchers conclude that vitamin E succinate may be of use in the treatment
of aggressive human breast cancers.
Turley, Jennifer M., et al. Vitamin E succinate induces Fas-mediated
apoptosis in estrogen receptor-negative human breast cancer cells. Cancer
Research, Vol. 57, March 1, 1997, pp. 881-90
Melatonin needs glutathione to combat breast cancer
COOPERSTOWN, NEW YORK. Melatonin, a hormone secreted by the pineal gland,
has been shown to inhibit the growth of human breast cancer cells in
concentrations (1 nM) similar to those encountered during the night when
melatonin production is at its peak. Now researchers at the Bassett Research
Institute report that the oncostatic (cancer-cell killing) effect of
melatonin depends on an adequate concentration of the body's natural
antioxidant glutathione. The researchers treated samples of breast tumor
cell lines in vitro with melatonin (1 nM) and found that the number of
cancer cells in the melatonin-treated substrates declined by 51 per cent
after five days in incubation when compared to the control samples. They
also observed that the glutathione levels remained much higher in the
melatonin-treated cells than in the control cells. Conversely, when
glutathione synthesis was artificially inhibited melatonin treatment no
longer retarded the growth of breast cancer cells. The researchers also
found that glutathione levels in cancer cells fell dramatically as the cells
multiplied. They conclude that glutathione is required in order to produce
the oncostatic effect of melatonin.
Blask, David E., et al. Physiological melatonin inhibition of human breast
cancer cell growth in vitro: Evidence for a glutathione-mediated pathway.
Cancer Research, Vol. 57, May 15, 1997, pp. 1909-14
Stress and cancer progression
COLUMBUS, OHIO. A diagnosis of breast cancer and subsequent surgery are
highly stressful events which can lead to chronic stress. Reseachers at the
Ohio State University now report that chronic stress in breast cancer
patients decreases the effectiveness of their immune system and may reduce
the benefits of adjuvant treatments such as radiation and chemotherapy. The
study involved 116 women with stage II or III breast cancer who had recently
undergone surgery. Before starting on additional treatments the patients
completed a questionnaire designed to evaluate their stress level. They also
gave blood samples which were analyzed for natural killer (NK) and T-
lymphocyte activity. The researchers found that women with higher stress
levels had impaired immune function as indicated by lower NK cell lysis
(ability to destroy cells), diminished response to recombinant interferon
gamma, and decreased T-cell activity. They speculate that patients with
impaired immune systems may be less able to resist progression of the cancer
and metastatic spread. Three studies are now underway to determine whether
stress reduction through support group intervention can indeed slow tumour
growth and disease progression.
Andersen, Barbara L., et al. Stress and immune responses after surgical
treatment for regional breast cancer. Journal of the National Cancer
Institute, Vol. 90, January 7, 1998, pp. 30-36
Cohen, Sheldon and Rabin, Bruce S. Psychologic stress, immunity, and cancer.
Journal of the National Cancer Institute, Vol. 90, January 7, 1998, pp. 3-4
(editorial)
McNeil, Caroline. Stress reduction: three trials test its impact on breast
cancer progression. Journal of the National Cancer Institute, Vol. 90,
January 7, 1998, pp. 12-14 (news)
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