GH de Bock, PhD (1) (2)
CJ van Asperen, MD (3)
JM de Vries, MD (1)
GCHA Hageman, MD (4)
MP Springer, PhD, MD (1)
J Kievit, PhD, MD (2)

Leiden University Medical Centre
(1) Department of General Practice
(2) Department of Medical Decision Making
(3) Department of Clinical Genetics
(4) Health Care Centre "Wantveld"
 

Correspondence to:
GH de Bock
Department of General Practice, Leiden University Medical Centre
P.O. Box 2088
2301 CB Leiden
The Netherlands

Telephone: -31-71-5275318
Facsimile: -31-71-5275325

E-mail: G.H.de_Bock@LUMC.NL
 

Summary

Objectives: To study the compliance with genetic advice given by GPs to women with a family history of breast cancer.

Design and setting: A longitudinal study in general practice.

Subjects: The compliance with a GP’s genetic advice was studied in 63 female patients.

Intervention: In 1995 these patients were interviewed about their familial breast cancer risk and were given a risk-specific genetic advice by their GP.

Main outcome measures: Three years later the GP registration about these patients was studied regarding the patient’s use of health care as a consequence of the GP’s genetic advice. Additionally, 42 patients were interviewed about factors related to their compliance with this advice.

Results: GP-surveillance was started more frequently than prescribed by the genetic centres. The patients appreciated it more when they were checked by their GP than when they were reassured or referred to a family cancer clinic. Nearly 25% of the women (10 out of 42) reported they performed monthly breast-self examination. One third of the women (15 out of 44) were compliant with the advice regarding GP-surveillance. Two thirds of the women (16 out of 24) discussed the genetic advice with family members.

Conclusion: The value of the genetic advice may be questioned, given the discrepancy between the GP’s advice and the accepted policy of genetic centres, in addition to the poor uptake of the GP’s advice by the patient and the lack of a clear result of the genetic advice.

Introduction

Breast cancer is the most common form of cancer in Western women, accounting for one-third of all cancer cases in women. A Dutch woman’s lifetime risk of developing breast cancer is 10%, whereas the risk of dying from breast cancer is about 5%. (1, 2) In the United States a woman’s lifetime risk for developing breast cancer is about 8%, whereas the lifetime risk of dying from breast cancer is 3.6%. (3) About 5% to 20% of all cases of breast cancer are thought to be familial (4, 5, 6), while about 5%-10% of these cases is attributed to the inherited cancer-susceptibility genes BRCA1 and BRCA2. (7)

As publications about hereditary breast cancer increase, and testing for these genetic mutations becomes more widely available, women with a family history of breast cancer will seek more information from their family physicians about risk assessment, genetic testing, and surveillance. (8,9) General practitioners (GPs) have an important role in identifying women at increased risk for breast cancer who might benefit from other preventive strategies than are recommended for the general population, such as surveillance under the age of 50.

Our aim was to study the compliance with genetic advice provided by GPs to women with a family history of breast cancer in a prospective longitudinal study with three years of follow-up. Additionally, women were interviewed about factors relating to their compliance with the GP’s genetic advice.

Methods

Setting

This study was performed in a university-linked primary health care centre in the Leiden area in The Netherlands serving 11,500 patients of whom 2,220 women were between 25 and 50 years of age (1995). In this centre, GPs use computerised medical records in which patients with specific risk factors and diseases can be marked and selected.

Patient cohort

The cohort consisted of women (n=81) consulting their family physician between April 1994 and July 1995 for advice about their risk of developing breast cancer because of a positive family history. (De Bock, 97) In the summer of 1995 these women were invited by letter to participate in a study about breast cancer in the family. If they wished to participate, they sent back an informed consent (n=67).

Design

After they gave informed consent, the participating women (n=67) were subsequently contacted by a trained interviewer for an interview. This interview consisted of a structured questionnaire on known familial risk factors for developing breast cancer. For each case of breast cancer in the family the following items were recorded: information about the age of onset, family relationship, bilaterality and breast cancer mortality. Information on ovarian cancer, and other cancers in the family was also recorded. For each woman a family tree was drawn. A clinical geneticist reviewed these family trees and assessed a personalised breast cancer risk for each woman based on the available data. Risk estimates were communicated as relative risks (RR) and were divided into three groups: a normal or slightly increased familial breast cancer risk (RR<2), a moderately increased familial breast cancer risk (2 £ RR < 3), a highly increased familial breast cancer risk (RR ³ 3). A normal or slightly increased familial breast cancer risk implied reassurance. A moderately increased familial breast cancer risk implied an advice for GP-surveillance (annual screening by mammography and palpation by the GP). A highly increased familial breast cancer risk implied a referral to a family cancer clinic. All women received an advice for monthly breast self-examination. Autumn 1995, the GPs discussed the GP’s genetic advice with each woman (n=63). In the computerised medical records a summary of the advice was written down. Four patients did not receive a genetic advice because they had left the practice during this period.

In the autumn of 1998, the computerised medical records (n=63) of all participating women who had received a genetic advice, were analyzed regarding the use of health care services. For 60 women, there was a three-year period of follow-up, for three women there was only a one-and-a half year-period of follow up, as two women left the practice and one woman died of leukemia. The 60 remaining women were invited for a second interview about the following topics: satisfaction with the advice given, breast self-examination in daily life, use of health care utilities, and reasons for being compliant (or not) with the GP’s genetic advice. As a genetic advice may affect a whole family, the women were asked whether or not they had discussed the GP’s genetic advice spontaneously with their (female) family members, as this is no explicit part of a genetic advice. All interviews (n=42) were performed by a trained interviewer. Due to the semi-structured nature of the interviews, they were taped and double transcribed. A summary of the interview was sent back to the women with a request for comments. In this paper the results regarding the compliance with the GP’s genetic advice and the factors related to the compliance with the GP’s genetic advice will be presented. The results of the first interview have already been published. (10)

Analysis

With respect to the advice given, we analysed 1) how the GP’s advice was related to the genetic risk assessment, 2) how it was appreciated, 3) whether patients were compliant with the advice and how they felt about the health care provided, and 4) to what extent they discussed matters with members of the family. To analyse compliance, three types of genetic advice were discerned:

1. An advice for a monthly breast self-examination. This advice was given to all women and compliance was assessed in 42 women during the interview.
2. An advice for GP-surveillance, including palpation and yearly mammography. This advice was given to 44 women (in several cases in combination with an advice for referral to a family cancer clinic). Compliance with this advice was assessed based on the GP registration. A woman was considered compliant if she had had at least two mammographies and had visited the GP twice for palpation when the follow-up had been three years, or at least one mammographies and one GP’s palpation when the follow-up had been one or two years. This shorter follow-up was due to the National Breast Cancer Screening programme (n=2), to the follow-up being transferred to the family cancer clinic (n=2), and to moving to another city (n=3).
3. An advice for referral to a family cancer clinic. Compliance with this advice was also based on the GP registration.

Results

Relation between GPs’ genetic advice and risk assessment

Based on the family trees as reviewed by the clinical geneticist, 30 (45%) women had a normal or slightly increased risk (RR<2), 18 (27%) had a moderately increased risk (2 £ RR < 3), and 19 (28%) women had a highly increased familial breast cancer risk (RR ³ 3) (Table 1). The genetic advice the GP actually gave was not in line with the policy by genetic centres in 30% of the cases. On the one hand, the GP started surveillance in eight women, whereas according to the clinical geneticist, reassurance was indicated (RR<2). On the other hand, the GP started surveillance in another 11 women, whereas according to the clinical geneticist, there was an indication to refer these women to a family cancer clinic (RR ³ 3).

How the advice was appreciated

Of the 19 reassured women, 12 were interviewed. Eight of these women were completely reassured by the advice, four were partly reassured. The main reason for being only partly reassured was that monthly breast-self examination was thought to provide less reassurance than yearly mammography.

Of the 36 women who had received the advice for GP-surveillance, 24 were interviewed. Most of them were more reassured by the genetic advice for yearly mammography than by the advice for palpation by the GP. A remark often heard was "can the GP feel more than I can myself?".

Of the eight women who got a GP’s genetic advice for GP-surveillance as well as a referral to a family cancer clinic, six were interviewed. Most of these women felt more comfortable with the genetic advice regarding GP-surveillance than with being referred to a family cancer clinic.

Compliance with the advice, and how women feel about it

Breast-self examination: 42 women were interviewed about the frequency of breast-self examination (Table 2). Nearly 25% of the women (n=10) reported they performed monthly breast-self examination, whereas more than 40% of the women (n=18) reported they never (or hardly ever) did that. Reasons mentioned for not doing a regular breast-self examination were: forgotten (n= 7); difficult to perform (n= 6); creepy, feels all kinds of lumps (n= 3); no time (n= 2).

GP’s palpation and yearly mammography: 44 women received an advice for GP’s palpation and yearly mammography. One third (n=15) of the women were compliant with the GP’s genetic advice regarding GP’s palpation and mammography, whereas 18 (40%) women neither went for palpation nor underwent mammography. 24 women (55%) did not undergo any palpation by the family physician (Table 3). Another 53% of the women (n=23) did not undergo mammography in the follow-up (Table 4). The compliance of the women had no statistically significant relation with the size of the RR. Reasons for not going for GP’s palpation or mammography were: forgotten; the problem of familial breast cancer is of no importance at this moment in life; no time. Of the compliant women that were interviewed (n=12), five performed monthly breast self-examination. Of the non-compliant women that were interviewed (n=18), 10 (nearly) never performed breast self-examination.

Referral: Eight women were offered GP-surveillance and were in addition also referred to a family cancer clinic. Five women actually visited the family cancer clinic. In two cases the family cancer clinic decided, after detailed examination of the patients’ family history, that the risk was not high enough to offer DNA-blood-testing. In three cases, the risk was high enough to offer DNA-blood-testing. For two of these patients the care regarding follow-up was transferred to the family cancer clinic, whereas for one patient the care was given by both the family cancer clinic and GP. Reasons for not visiting the family cancer clinic were: the family had no wish to participate (n=1); no time (n=1); no interest in DNA-blood-test-results (n=1).

To what extent did women discuss the advice with their family members

Of the 10 interviewed women with a moderately increased familial breast cancer risk (2 £ RR < 3), eight spontaneously discussed the GP’s genetic advice with their (female) family members. Of the 14 interviewed women with a highly increased familial breast cancer risk (RR ³ 3), nine discussed the GP’s genetic advice with their (female) family members.
 

Discussion

GPs gave an advice regarding surveillance more frequently than the accepted policy by genetic centres prescribes, in 70% of the patients (44 out of 63) the GP was compliant with the accepted policy. This discrepancy went two ways. On the one hand, the GP started surveillance in eight women, whereas according to the clinical geneticist reassurance was indicated. On the other hand, for another 11 women, the GP started surveillance, whereas according to the clinical geneticist there was an indication to refer these women to a family cancer clinic. This discrepancy is in line with a recently developed and published Dutch set of GP guidelines to assess the genetic risk of breast cancer among relatives without breast cancer. (11) Regarding the indication for referral to a family cancer clinic, this set of GP guidelines was very specific, and regarding surveillance, the set of GP’s guidelines was very sensitive. (11)

The compliance with the GP’s genetic advice was poor. Nearly 25% of the women (10 out of 42) reported they performed monthly breast-self examination, and one third of the women (15 out of 44) were compliant with the GP’s genetic advice regarding GP’s palpation and mammography. The findings of this study are in line with those of other studies. (12, 13, 14, 15) Although relatives of breast cancer patients selected from a family cancer clinic adhere to the recommended mammography screening guidelines (12), low compliance was reported with yearly mammography for a-symptomatic breast cancer relatives in general practice. (13) Moreover, it was reported that as far as screening behaviour is concerned, relatives of breast cancer patients did not differ substantially from women in the general population. (14, 15)

The GP’s genetic advice included performing monthly breast-self examination, yearly palpation by the GP and yearly mammography. In recent studies no reduction in mortality was found due to breast self-examination, even when there had been a good instruction. (16, 17) There are no randomised prospective trials in which the diagnostic value of palpation by a physician was studied. In two randomised trials in which the diagnostic value of palpation by a physician in combination with breast self-examination was studied no reduction in mortality was found. (18, 19, 20) Moreover, there is no better stage distribution in tumours detected by palpation by a physician as than detected by breast self-examination. (21) The diagnostic value of mammography in women without breast symptoms is lower in women under 50 years of age, due to higher breast densities and tumour growth rates in younger women. (22, 23, 24, 25) For these reasons, it is unclear to what extent the women may truly benefit from the advice. (26) The diagnostic value of mammography for women under 35 years of age without breast symptoms is doubtful. (27)

Given the discrepancy between the GP’s genetic advice and the accepted policy by genetic centres, the poor uptake of the GP’s genetic advice by the patient and the lack of a clear result of the genetic advice, it can be questioned whether this genetic advice is valuable. More research is needed to see which elements in this advice can improve the length and quality of the life of a woman with a family history of breast cancer, and how the uptake of the genetic advice in general practice can be improved.

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