Document Dd8g6x2g4Vn6rxnxMNnbrX415
FILE NAME Talc TALC
DATE 1992
DOC TALC029 DOCUMENT DESCRIPTION Journal Article - Mineral Fiber
Exposure and the Development of Ovarian Cancer
GYNECOLOGIC ONCOLOGY 45 20-25 1992
Mineral Fiber Exposure and the Development of Ovarian Cancer o
The
KARIN A. ROSENBLATT PH.D MOYSES SZKLO M.D. DR.P.H NEIL B. ROSENSHEIN M.D.
*
material Department of Epidemiology The Johns Hopkins School of Hygiene and Public Health Baltimore Maryland 21218 and +
Gynecology and Obstetrics The Johns Hopkins Hospital Baltimore
21218
Department of
Maryland
on
Received July 10 1991
this
A hospital control study of the association between fiber exposure and the development of epithelial ovarian cancer
was performed at the Johns Hopkins Hospital in Baltimore Mary-
land Genital and respiratory fiber exposures were ascertained from incident cases N = 77 and race matched controls N = 46 using a structured questionnaire Cases were ascertained
between 1981 and 1985. An increased risk was observed for ex-
posure to talc on sanitary napkins OR = 4.79 95 CI = 1.2917.79 genital fiber exposure from different sources for a long cumulative exposure 37.y4ears length of time OR = 2.35 95 CI = 0.95 5.8a0nd occupational fiber exposure in relatives OR = 2.81 95 CI = 0.90 8.7A 5 negative association was observed for antecedent tubal ligation OR = 0.15 95 CI = 0.027-0.88 Findings from this study should be confirmed in larger investigations '1992 Academic Press Inc.
INTRODUCTION
Occupational exposure to asbestos has been identified as a risk factor for ovarian cancer in several studies 13 Similarly containing substances such as talc have also been implicated as risk factors 4-9 A matched control study of epithelial ovarian cancer was conducted in which the role of both genital and respiratory
sources of fiber was assessed to confirm these findings
STUDY POPULATION
Cases and controls were ascertained from the Johns
Hopkins Hospital between 1981 and 1985. This analysis
is restricted to the 77 cases who were matched to 46
hospital controls and treated for conditions other than gynecologic or malignant diseases Originally 140 newly diagnosed cases of epithelial ovarian cancer who met the
'
Present address Department of Health and Safety Studies University of Illinois at Champaign 120 Huff Hall 1206 S. Fourth St. Champaign IL 61820 Correspondence to Dr. Rosenblatt at this address
page eligibility criteria were ascertained from the Johns Hop- :
. was kins Hospital One hundred eight 77.1 of these cases
were successfully interviewed These cases were diag-
copied nosed within 6 months of admission were pathologically
confirmed by examination of the ovaries were admitted -
as patients for treatment or diagnosis and were resi- from
dents of the United States Controls were patient fe- the males without gynecologic or malignant conditions who
colection were initially matched to cases by age within 5
years race and date of diagnostic admission within 1 year%
Since it was difficult to find controls meeting all of
of
the matching criteria a control could not be found for all + the
cases
teriori and 1
National within
Unmatched cases were therefore matched a pos-= to controls to form matched triplets of 2 cases
control A posteriori matching was performed ; the same year interval by race and by closest
Library date of diagnostic admission The matching procedure ~
allowed for the inclusion of 77 cases in the study There of
were 46 matched sets of which 31 consisted of 2 cases
and 1 control No matched control could be found for 13
cases which were excluded from the analysis
Medicne
by
METHODS
a
third Data were ascertained primarily from a questionnaire ~
party that was administered to participants both by telephone |
and and in the hospital Information on previous abdominal -
and gynecologic operations was also ascertained from .
medical records
may
The questionnaire elicited information on the presence ; be
and length of genital fiber and respiratory fiber exposure |
protected reproductive factors estrogen use family history of can- *
cer in degree relatives and other contraceptive use
Descriptions of the questions used to ascertain fiber ex- by
posure are listed in Appendix 1. Fiber exposure was de- US US
fined as exposure to asbestos talc which may contain
Copyright asbestos and fiberglass An attempt was made to estimate the overall effect of
20 0090-8258 1.50
Copyright '1992 by Academic Press Inc. All rights of reproduction in any form reserved
law
.
FIBERS AND OVARIAN CANCER
21
dose or length of genital and respiratory fiber exposure This was accomplished by adding the number of years of each type of genital or respiratory exposure from all
sources Since many of these exposures occurred at the
same time these variables should be considered as crude measures of dose rather than the true length of exposure
Conditional logistic regression 10 was used to determine the strength of the association Odds ratios were calculated to describe the relationship of genital and respiratory fiber exposure to ovarian cancer The odds ratio is an estimate of the relative risk for relatively rare dis-
eases such as ovarian cancer and in this paper is referred
to as the relative risk estimate RR The following variables were assessed as potential
confounders
Tobacco use
Number of cigarettes per day Ovulatory time period Number of pregnancies
Cancer in mother or father
Obesity 1 year prior to diagnosis Obesity 20 years prior to diagnosis Obesity at highest weight during the 20 years prior to diagnosis Obesity according to average weight during the 20 years prior to diagnosis Husband's and subject's education
Previous cancer
Marital status
Religion Use of oral contraceptives Use of contraceptive foams creams and jellies by
themselves
Use of an IUD
On the basis of the strength of their relative risk estimates and the difference in frequency with which they were observed in cases and controls the following variables were identified as potential confounders measures of obesity socioeconomic status subject's education RR = 0.5 95 CI = 0.2-1.1 and religion Jewish RR 2.9 95 CI = 0.6-13.8 Catholic RR = 0.5 95 CI = 0.2-1.5 reproductive status total live births 1-2
RR = 0.7 95 CI = 0.2-1.9 live births > RR =
0.4 95 CI = 0.2-1.3 and oral contraceptive use OR = 0.9 95 CI = 0.3-23.0
Obesity 1 year prior to diagnosis RR = 2.3 95 CI = 0.9-6.1 obesity 20 years prior to diagnosis RR = 2.1 95 CI = 0.7-6.9 and obesity according to highest weight during the 20 years prior to diagnosis RR = 1.5 95 CI = 0.7-3.2 were also found to be potential confounders Obesity was defined as a weight index greater than that exhibited by women in the 85th percentile 11 of the population
TABLE 1 Distribution of Matched Cases and Controls
Cases
Controls
N
%
N
%
The
The
Age years
material
Less than 30
311235
30-39
31 235
40-49
311235
3.9 1.3 14.3
21822
4.4 material
2182
material
21822
17.4
50-59
311235
27.3
21822
21.7
60-69
311235
45.4
21822
this
70-79
311235
6.5
3
page
80 or higher
-
1.3
-
2.2
Total
Race
White
Black
Total
77
46
was
was
- copied
27F
90.9
41
89.1
copied 10.S 27F
9.1
5
10.S
77
45
from
"the
If a potential confounder changed the relative risk es
col ection timate associated with a fiber exposure by more than %colection
it was retained in the multivariate model Confoundercolection
depend of were sequentially added to multivariate models
of
the
rati ing on the level with which they changed the odds
of a fiber related exposure
ththe e :
National Interaction between fiber exposures and potential conNational
founders was evaluated by comparing the deviance o
models with and without the interaction term 12 Library
RESULTS
of
Medicine Age and Racial Distribution ke Table 1 lists the age and racial distribution of cases an controls Most cases and controls were in the age group a
40 to 69. It was difficult to obtain controls that did nc third
expecte have a chronic disease resultingin a lower than
number of controls
and
Diagnoses of Controls
themaiy Controls were selected so that they did not have be
Tabl primary diagnostic condition for more than 1 year
2 lists the
the study
primary
diagnosis of the controls included
protectedprotecprtoteecdted
Genital Fiber Exposure
ty
2by
es Different sources of genital fiber exposure were
amined Table 3 Exposure from any of the
Copyright
potentia sources of genital fiber was highly prevalent 91.1 Copyright
controls and not found to be related to ovarian canceCopyright
RR= 1.0 95 CI = 0.2-4.0 Since it was felt thalalwaw
this index did not accurately characterize cumulative ex
posure the median length of exposure from all genita
sources with the time since tubal ligation subtracted was
22
ROSENBLATT SZKLO AND ROSENSHEIN
TABLE 2
Distribution of Matched Controls by Primary Diagnosis
Diagnosis of restricted controls
N
%
Infectious and parasitic diseases Diseases of the digestive system Opthamologic disorders Diseases of the circulatory system Symptoms signs and defined conditions
Diseases of musculoskeletal and connective
tissue
Diseases of the endocrine system or metabolic or immunologic disorders
Diseases of the respiratory system
Benign neoplasms Injury and poisoning
Total
1
2.2
6
13.0
15
32.6
11
23.9
8
17.4
1
2.2
1
2.2
1
2.2
1
2.2
1
2.2
46 = 100.00
used to categorize the dose of genital fiber exposure A relative risk estimate of borderline significance was seen for exposure above the median length of time 37.4 years RR = 2.4 95 CI = 1.0-5.8 A significant negative association was observed for previous tubal ligation RR = 0.2 95 CI = 0.03-0.9
A history of several gynecologic and abdominal operations given by responses to the questionnaire was examined to determine if exposure to talc from surgeon's gloves increased risk 13 No statistically significant relationships were detected but with the exception of ovarian biopsies relative risk estimates were generally below 1. An attempt was made to combine information from the questionnaire and medical records with no important changes in the relative risk estimates
Moderately elevated relative risk estimates which were not statistically significant were observed with use of condoms diaphragms when powder was used and genital
bath talc The level of association observed with exposure
to talc on sanitary napkins RR = 4.8 95 CI = 1.318.0 was significantly greater than unity
Respiratory Fiber Exposure
Numerous sources of respiratory fiber exposure were evaluated Table 4 the only such source showing an important effect was occupational fiber exposure in relatives RR = 2.8 95 CI = 0.9-8.8 This relative risk
estimate was calculated after three cases who were both
exposed to asbestos themselves and received asbestos ex-
posure from their relatives were excluded
DISCUSSION
Genital talc exposure has been proposed as an etiologic agent of ovarian cancer 14 because talc was observed more frequently in cancerous ovaries 15 than in noncancerous ovaries occupational studies of containing
asbestos showed an increased risk of lung cancer 16
asbestos has been observed in cosmetic face powders 17-
19 and papillary growth has been observed after im-
plantation of asbestos 20 and tale 21 into the peritoneal
"
cavity We found an increased relative risk 4.8 for talc use
on sanitary napkins with a smaller effect for genital bath The
talc exposure RR = 1.7 This is in accordance with the
material original finding of a significant increased risk for perineal
talc exposure RR = 1.9 95 CI = 1.3-2.9 by Cramer et al 4 Preliminary findings from a Chinese study also on
suggest that perineal application of containing dusting this
page powder increased the risk of epithelial ovarian cancer RR
= 3.9 95 CI = 1.1-13.8 5 A nonsignificant effect
for genital talc exposure on genitals sanitary napkins was
or underwear was detected in the study of Hartge et al
copied 6 RR = 2.5 95 CI = 0.7-10.0 Whittemore et al
7 detected an increased risk RR = 1.4 P = 0.06 for
from perineal exposure In a study of borderline ovarian tu-
mors an increased risk was also observed with talc ex- the
posure from use on sanitary napkins RR = 1.9 95
cumulaticovleection CI= 0.9-6.9 8 We also investigated the relationship with duration of all forms of genital fiber exposure with the of
= time since tubal ligation subtracted The positive asso- the
ciation RR 2.35 in our study for exposure longer
National than the median length of time contrasts with the lack of
association with duration observed by Whittemore et al
Library 7 Whittemore et al 7 however did observe a positive
response relationship with frequency of exposure 1-20 times per month RR = 1.3 95 CI = 0.8-2.0 of
20 times per month RR = 1.4 95 CI - 0.9-2.2
Although Booth et al 9 did not observe a significant P= 0.05 trend of increasing risk with more frequent
Medicne
use weekly genital talc use RR= 2.0
3.4 was associated with an increased
cancer
95 risk
= CI 1.3 by a
of ovarian
third
The
results
of
our
study
and
others
suggest
that
genitalgenital
party party
fiber exposure may be associated with an adverse effect party
4-8 but further study is needed to determine if this and
may relationshipis causal in nature
negative The present study also showed a significant
association with tubal ligation RR= 0.15 Harlow 22 protected
= protected = 0.3 95 CI 0.3-1.1 Booth et al 9 RR
RR = = protected =
0.2 95
CI
0.1-0.6 Mori et al
23 RR
0.4
protected
95 CI= 0.2-1.0 Whittemore et al 7 RR= 0.6 P = 0.07 and Irwin et al 24 RR= 0.7 95 CI by
0.5-1.0 also observed negative associations Although
the findings of our study differ from the positive associ- Copyright
Copyright ation observed by Koch et al 25 the comparison rateCsopyright
26 used in Koch's cohort study may have been
protect underestimated Tubal ligation may
l| aw
law
against ovarian cancer by
inhibiting the carcinogenic action of talc through blockage
FIBERS AND OVARIAN CANCER
23
TABLE 3
Number and Frequency Distribution of Cases and Controls with Odds Ratios for Genital Fiber Exposure
and Other Related Variables
Exposure interval
Attribute
Cases
S UEEEEEEEEEEEEEEEEET
N
/
Controls
os
N
%
Genital fiber use
Length of use of genital fiber years
Median of cases and controls
Ovarian biopsies Unilateral oophorectomy Tubal ligation
Hysterectomy
Condom use
Diaphragm use with
powder
Genital bath talc
Sanitary napkin with talc
exposure
Yes
No
Missing
37.4 37.4
Missing Median
Yes No Yes No
Yes
No Yes No
Yes
No
Missing
Yes No
Missing
Yes No
Missing
Yes No
Missing
67
87.0
40
10
13.0
5
0
1
39
55.7
16
31
44.3
25
7
5
41.9
6
7.8
3
71
92.2
43
8
10.4
5
69
89.6
41
4
5.2
6
73
94.8
40
19
24.7
12
58
75.3
34
35
49.3
22
37
50.7
21
5
3
14
18.9
5
60
81.1
39
3
2
22
28.9
8
54
71.0
35
1
:
21
30.0
6
49
70.0
38
7
2
a
After subtraction of the time since tubal ligation for those
b
Adjusted for number of live births
--
Adjusted for religion
d
Adjusted for years of education on subject
*
Adjusted for highest weight 20 years prior to diagnosis
Adjusted for highest weight 1 year prior to diagnosis
who
had
ligation
88.0 11.1
39.0 61.0
24.0
6.5 93.5 10.9 89.1 13.0 87.6 26.1 73.9 51.2 48.8
11.4 88.6
18.6 81.4
13.6 86.4
Odds ratio 1.0 2.4
1.1 0.8 0.2 0.7 1.6 3.0 1.7 4.8
;
*
95 confidence
interval
The
0.2-4.0
material
1.0-5.8
on
this
page
0.3-4.4
was
:
0.2-2.5 . copied
0.3-0.94
from
0.3-1.74
* the
0.6-3.9
.
*
col
ection
0.8-10.874
of
: the
x
0.7-3.9
-
National
1.3-17.8
Library
of
Medicne
by
a
third
of the fallopian tube or through a screening effect 27 The effects of antecedent tubal ligation should be eval-
uated in future studies of ovarian cancer to determine if
a negative association is consistently observed and to de-
termine the reason for this
Several cohort studies of women with respiratory ex-
posure to asbestos detected an increased relative risk for
ovarian cancer 1-3 We elicited information about em-
ployment by relatives in occupations with asbestos or fi-
berglass exposure 28 and the relative risk was found to
be elevated RR = 2.8 In a previous control study
of ovarian cancer the relative risk for occupational as-
bestos exposure in relatives
though the authors did not
was not describe
elevated how the
29 al-
asbestos
exposure was ascertained Our initially suggestive findings
regarding asbestos or fiberglass exposure in relatives
should be evaluated further in additional studies
In summary our study shows that the development of
ovarian cancer may be associated with genital fiber ex-party
posure especially talc on sanitary napkins and occupa- and
may tional exposure to fibers in relatives Given its small sam-
ple size and the potential selection bias stemming from inclusion of patients from only one hospital further re- be
search needs to be performed in order to confirm our
findings
protected
by
APPENDIX 1
U
S.
Questions Asked to Ascertain Fiber Exposures
Copyright Genital Fiber Exposure
1. Have you had any of the following operations prior
law
to your hospitalization in
?
.
-Biopsy or removal of part of an ovary
-Removal of one ovary
-Removal of uterus hysterectomy
24 ROSENBLATT SZKLO AND ROSENSHEIN
TABLE 4
Number and Frequency Distribution of Cases and Controls with Odds Ratios for Selected Characteristics Related to Respiratory Fiber Exposure
Exposure interval
Attribute
Cases
N
%
Controls
N
%
Odds ratio
95 confi interv The
Respiratory fiber exposure
Cosmetic face powder use
Yes No Yes No
69
89.6
41
89.1
1.3
ww
10.4
3222EX
10.4
54.5 ww
50.7
3222EX
1.1
ww
49.3
3222EX
45.4
Insulation installed at residence
Missing
~
3222EX
Yes
w
39.5
3222EX
37.8
1.2
No
*
60.5
3222EX
62.2
Missing
1
1
Living in the vicinity of a fi-
Yes
7
9.2
4
8.9
1.0
90.8 emitting industrial
No
69
41
91.1
establishment
Missing 1
1
Applied bath talc to body respiratory exposure
Fiber exposure in relatives
Yes
47
61.8
24
55.8
1.6
No
Missing
29
38.2
19
44.2
1
3
Yes
18
24.3
5
10.9
2.8
Missing No
Use of spackling and taping
Yes
compounds
No
56
75.7
41
89.1
20
29.0
14
31.1
1.6
49
71.0
31
68.9
8
1
*
0.3-3.1 material
material
0.4-2 on this
this
0.3-4 page
was
0.3-3,4 was
copied
copied
0.6-2.1 from
from
the
0.9-8 . the
collection
0.5-3.4 colection collection
of
Adjusted for highest weight 1 year prior to diagnosis
b
Adjusted for years of education on subject
Adjusted for number of live births
the National
National d
Three cases were excluded because they had been directly exposed to fibers and had a household household
National
ex. posed to fibers Fiber exposure included asbestos talc or fiberglass exposure
occupati member who had been
National
National
Adjusted for religion
Library
-Tubal ligation
-Any other abdominal operation These items were confirmed by examination of medical
records
2. Did you use a diaphragm prior to your hospitalization
in
?
If yes Did you use a powder to dust and dry the diaphragm
If yes Was it talc
3. Did you and your sexual partner ever use a condom
prior to your hospitalization in
?
4. Have you regularly applied talcum powder to your
body after bathing or for other reasons prior to your
hospitalization in
?
Did you commonly apply the talcum powder to your genital area
5. Have you used talc on sanitary napkins or any other
sanitary products used during your menstrual period prior
to your hospitalization in
?
Respiratory Fiber Exposure 1. Prior to your hospitalization in
had you ever
of
3. Have you ever lived in the vicinity of a shipyard Medicine asbestos or talc mine or an asbestos talc or fiber~flMedicine processing plant prior to your hospitalization in __2 Medicine
4. Have you regularly applied talcum powder to by body after bathing or for other reasons prior to third
hospitalization in
?
i third
party Did you commonly apply the talcum powder to4 party
face upper torso or legs and feet
5. Have you or anyone who has ever lived in 3 and
may household including your husband been employe
any of the following industries prior to your hospi
zation in
?
be
:
protec d materia a Installation or removal of insulation
b Brake lining manufacture
c Automobile repair involving brake repair
d Roofing using asbestos materials
by
U
e Asbestos milling or mining
S.
f Asbestos textile or paper manufacture
Copyright g Building construction
h Other industries where asbestos is used
i Talc mining and milling
law
j Other industries where talc is used
regularly used cosmetic face powder
2. Have you ever had insulation installed in a place
that you lived in prior to your hospitalization in
?
k Fiberglass or mineral wool manufacture 1 Other industries where fiberglass or mineral wool
was used
FIBERS AND OVARIAN CANCER 25
6. Did you ever use spackling and taping compounds
If the respondent answered yes to any of these questions they were asked when the exposure started and stopped If they could not answer this question they were asked how long the exposure occurred
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a
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Copyright
law