Impact of medical and demographic factors on long-term quality of life and body image of breast cancer patients

K. Härtl+, W. Janni, R. Kästner, H. Sommer, B. Strobl, B. Rack and M. Stauber

I. Frauenklinik, Klinikum der Ludwig-Maximilians-Universität München, Munich, Germany

Received 30 August 2002; revised 3 March 2003; accepted 17 March 2003


    Abstract
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Background:

The impact of various medical and demographic factors on the quality of life (QoL) of breast cancer patients has been discussed controversially. We investigated the influence of six different factors on long-term QoL and body image of women with primary breast cancer.

Patients and methods:

Two-hundred and seventy-four breast cancer patients were administered the QoL questionnaire following a mean interval of 4.2 years after primary diagnosis. All women had been primarily treated for stage I to III breast cancer without evidence of distant metastases. QoL was evaluated by using the QLQ-C30 questionnaire Version 2.0. Supplementary scales included body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence. We analyzed the impact of tumor stage, surgical treatment, adjuvant radiotherapy, adjuvant cytotoxic therapy, age and length of follow-up period on the examined outcome parameters.

Results:

At the time of the follow-up examination, patients showed minor impairment of QoL (mean 67.8) and body image (mean 24.8), but more fear of recurrence (mean 60.7). None of the studied factors had a significant impact on overall QoL (P >0.05) according to the QLQ-C30 questionnaire. In contrast, with the exception of the factors ‘cytotoxic therapy’ and ‘radiotherapy’ all investigated variables influenced at least one of the additional psychological scales (P <0.05). The primary surgical treatment modality had the strongest impact and affected all four scales. Patients treated with breast conservation reported a more favorable body image, compared to those treated with mastectomy (17.2 versus 37.5, P <0.01), more satisfaction with surgical treatment (4.0 versus 10.7, P = 0.01), rated a better cosmetic result (75.5 versus 57.1, P <0.01), but presented more fear of recurrence (63.9 versus 55.3, P = 0.04).

Conclusion:

Current QoL questionnaires do not sufficiently cover all relevant aspects of QoL, but might be complemented by breast cancer specific aspects such as body image and fear.

Key words: body image, breast cancer, fear of recurrence, follow-up study, quality of life


    Introduction
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Diagnosis and treatment of breast cancer can affect psychological, sexual and physical functioning to a great extent, and therefore health-related quality of life (QoL) is included in many studies as an outcome parameter to compare different breast cancer treatments [1, 2]. It can be argued that the improvement of QoL should be a primary goal of cancer care [2]. However, QoL addresses multiple dimensions of life with a wide variety of divergent definitions of the construct. As a consequence, a vast range of assessment tools is available and often heterogeneous results in different studies are found [35]. In this study QoL includes, in line with other studies [69], the patients’ subjective view of their current physical, social, emotional and cognitive functioning as well as psychological parameters of fear, body image, satisfaction with health care and attitudes towards the cosmetic result of the surgical treatment.

There is a lack of data on possible interactions between psychological, medical and sociodemographic factors and QoL [1, 7]. The findings on QoL among long-term survivors of breast cancer are heterogeneous, often contradictory [5, 7, 8, 10]. Several studies investigated the impact of a single parameter, mainly compounds of primary treatment, on QoL of breast cancer patients. Most major studies focused on the impact of primary surgical treatment modality [3, 6, 11, 12], age [1315] and adjuvant chemotherapy [7, 16] on QoL, while other factors, such as tumor stage, adjuvant radiotherapy or follow-up period were often neglected. However, the impact of these factors on the QoL has been discussed controversially. In addition, there is a lack of studies which investigate the differential impact of several oncological and demographic factors on long-term QoL within one clinical trial.

The purpose of the present study was to evaluate the impact of various tumor and treatment associated variables, as well as demographic factors on long-term QoL, fear of recurrence, body image, satisfaction with surgical treatment and cosmetic result.


    Patients and methods
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Patients
Two-hundred and seventy-four women with breast cancer were administered QoL questionnaires at the I. Frauenklinik, Ludwig-Maximilians-Universität München as part of routine follow-up examinations. Eligible patients included those women who had previously undergone primary surgical therapy, breast conservation or mastectomy at our hospital at the time of primary diagnosis of stage I to III breast cancer. Only patients without any evidence of recurrence of the disease during the follow-up interval were included in the study. Twenty-two patients who had initially took part in the study, but had a relapse during the follow-up interval were excluded. Thus, at time of examination, all 274 patients were without evidence of active breast cancer disease.

Primary treatment
The primary surgical treatment consisted of either breast conserving therapy (BCT; 171 patients) or modified radical mastectomy (103 patients) leading to R0 resection in all reported cases. Routine axillary dissection included lymph nodes of levels I and II, while those of level III were excised only in cases with macroscopic metastatic involvement of the lower levels. For the diagnosis of lymph node metastasis, single embedded lymph nodes were screened at up to three levels. Breast reconstruction was not available at the study site and was not offered to the patients. Telecobalt radiotherapy was administered to 164 of 171 patients (95.9%) treated with breast conservation. Chest wall irradiation following mastectomy was performed in 35 patients (34.0%) with large tumors of extensive lymphangiosis carcinomatosa. Postmenopausal patients with positive hormone receptor status (29 patients) received adjuvant endocrine therapy with tamoxifen (20 mg/day). The duration of tamoxifen was 5 years; 21 of the patients were still receiving tamoxifen at the time of assessment. According to local policies, all premenopausal patients with axillary lymph node metastases received adjuvant chemotherapy (69 patients). Patients with one to three involved axillary lymph nodes received cytotoxic therapy that consisted of six cycles of CMF [cyclophosphamide (600 mg/m2 body surface area), methotrexate (40 mg/m2), 5-fluoruoracil (600 mg/m2)] every 21 days. In patients with four or more regional lymph nodes four sequential courses of EC [epirubicin (90 mg/m2) and cyclophosphamide (600 mg/m2)] followed by three courses of CMF were given in some cases, while other patients received six courses of DE [epirubicin (90 mg/m2) and docetaxel (75 mg/m2)]. No systemic adjuvant therapy was given to 109 node-negative patients.

Assessment of quality of life, body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence
Quality of life was evaluated by using the QLQ-C30 questionnaire, Version 2.0 of the European Organisation for Research and Treatment of Cancer (EORTC) Study Group on Quality of Life [17, 18]. The questionnaire is composed of the Global Health Status/QoL scale and five functional scales that evaluate physical functioning, role functioning, emotional functioning, cognitive functioning and social functioning. Higher mean scores on these scales represent better functioning and QoL. Three symptom scales measure nausea and vomiting, pain and fatigue. Six single items assess financial impact and physical symptoms of dyspnea, insomnia, appetite loss, constipation and diarrhea. Higher mean values on the symptom scales and single items translate into an increased extent of symptoms.

In addition to the EORTC QLQ-C30 questionnaire, six supplementary items were appended. The hypothesized scale structure of the added items included a body image scale consisting of two questions, a scale that evaluates satisfaction with the primary surgical treatment consisting of two questions, a single item concerning fear of recurrence and a single item on cosmetic result. Higher mean scores on the additional scales represent a more negative body image, less satisfaction with surgical treatment, higher fear of recurrence and a greater satisfaction with the cosmetic result. Variations of these questions have also been used in other studies [6].

Medical and demographic factors
We investigated the following tumor and treatment associated factors: tumor stage at the time of primary diagnosis, primary surgical treatment modality (BCT versus mastectomy), adjuvant radiotherapy (no radiotherapy versus radiotherapy) and adjuvant cytotoxic therapy (no cytotoxic therapy versus cytotoxic therapy). The tumor stage at the time of primary diagnosis was classified according to the International Union Against Cancer (UICC) tumor node metastasis (TNM) classification [19, 20]. The investigated demographic factors comprised the patient’s age at time of follow-up examination and length of follow-up period, i.e. the interval between primary diagnosis of breast cancer and study visit. Patients’ age was dichotomized in the two categories <=59 years and >59 years. The follow-up period was categorized as <1, 1–2, 3–6 and >6 years.

Statistical analysis
Linear transformation was used to standardize the raw scores of the psychological variables so that all scores ranged from 0 to 100. In accordance with ‘The EORTC QLQ-C30 Scoring Manual’ [21], the questionnaire items were encapsulated in scales of the categories ‘Global Health Status QoL, Functional Scales and Symptom Scales’. The additional scales were evaluated statistically in analogy to the symptom scales [21]. Multitrait scaling analysis was employed to verify the hypothesized scale structure of the ‘body image’ scale and the ‘satisfaction with the primary surgical treatment’ scale. Evidence of item convergent validity was defined as a correlation of >=0.40 between an item and its own scale, corrected for overlap [6]. In addition, the reliability of the two scales was assessed using Cronbach’s {alpha}-coefficient. To confirm the discriminative validity of the additional variables we examined correlations among the four scales. Substantial correlation between the scales was ruled out if Pearson’s correlation coefficient was r <0.40.

We performed analyses of variance (ANOVA) to test for associations between the tumor and treatment associated variables as well as demographic factors and various psychological parameters at the time of the follow-up examination. For this analysis we assessed each of the tumor and treatment associated variables (tumor stage, primary surgical treatment, radiotherapy, cytotoxic therapy) and demographic factors (age, follow-up period), creating a separate ANOVA model for each of the QoL measures (QoL and four functional scales) and for each of the additional scales (body image, satisfaction with surgical treatment, cosmetic result, fear of recurrence). No adjustment was made for multiple comparisons. We used two-sided P-values as descriptive statistics to identify associations between the dependent variables and the independent factors. If the ANOVA indicated significant impact of the observed factor on the QoL and additional scales (P <0.05), we reported means and standard deviations (SDs) within each comparison. In addition, correlation analyses (Spearman-Rho-coefficients and Phi-coefficients) of the six independent variables were calculated and if two independent variables were interrelated (r >0.4), an analysis of covariance (ANCOVA) was conducted. The computer software ‘Statistical Package for the Social Sciences 10.0’ (SPSS Inc., Chicago, USA) was used for all calculations.


    Results
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Patients’ characteristics at time of primary diagnosis
The mean age of the 274 participating patients at time of primary diagnosis was 55.8 years (range 27.5–99.5, SD 11.5). According to the UICC, 48.9% of the patients were diagnosed with stage I disease, 25.5% with stage IIA, 13.5% with stage IIB, 10.9% with stage IIIA and only 1.1% with stage IIIB. Of the 274 patients, 171 (62.4%) were treated with BCT and 103 (37.6%) with mastectomy. Patients’ clinical characteristics at time of primary diagnosis are summarized in Table 1.


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Table 1. Clinical characteristics of the 274 patients at time of primary diagnosis
 
Reliability and validity of the additional scales
Corrected for overlap, all item scale correlations of the appended ‘body image’ scale and the ‘satisfaction with surgical treatment’ scale showed a correlation coefficient >=0.58 and thus exceeded the 0.40 limit for item-convergent validity for both scales. Cronbach’s {alpha}-reliability coefficients of the two scales (0.75 and 0.64) were adequate. Concerning inter-scale correlations of the four additional scales, all Pearson r correlation coefficients were moderate (r <=0.34), indicating that the scales assess distinct psychological variables.

Quality of life, body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence at the time of follow-up examination
The questionnaires were answered after a mean interval of 4.2 years (SD 4.5) following primary treatment. The average age of the patients at the time of the follow-up examination was 60.0 years (SD 11.6). Table 2 shows the mean values and SDs of the QoL scale, functional scales and symptom scales according to the QLQ-C30 questionnaire and of the additional scales.


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Table 2. Quality of life, body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence evaluated by the QLQ-C30 questionnaire and additional scales (274 patients)
 
The mean values of the overall QoL scale (67.8) and of the functional scales (all >60) were above average, and thus demonstrated moderate impairments. The symptom scales in general showed a low degree of symptoms. The most frequent complaints were insomnia (41.4), fatigue (34.5) and pain (27.4). Nausea and vomiting (5.7), diarrhea (5.4), appetite loss (8.5) and constipation (9.9) were rarely reported. The additional scales demonstrated little impairment of the patients’ body image (24.8), high satisfaction with surgical treatment (6.5) and favorable cosmetic results (68.6). However, a considerable amount of fear of recurrent breast cancer (60.7) was observed.

Correlation analyses of the independent variables
With two exceptions, all correlations of the six independent variables were low: the Spearman-Rho-coefficients and Phi-coefficients were <0.3. The Spearman-Rho correlation between tumor stage and cytotoxic therapy was moderate (0.40, P <0.01). Patients with better tumor stage classification had less treatment with cytotoxic therapy than patients with worse tumor stage. The variables ‘primary surgical treatment’ and ‘radiotherapy’ were highly interrelated (Spearman-Rho –0.67, P <0.01). Women having BCT were more often treated with radiotherapy than women with mastectomy. Because of the interaction of primary surgical treatment and radiotherapy analyses of covariance were conducted.

Impact of medical and demographic factors on quality of life
Tables 3 and 4 illustrate the impact of tumor and treatment associated variables and demographic factors on QoL and the functional scales of the QLQ-C30 questionnaire. Table 3 shows the two-sided P-values of the ANOVA, while Table 4 shows the mean values and SDs of the functional scales according to the various subgroups.


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Table 3. Impact of medical and demographic factors on quality of life and the functional scales of the QLQ-C30 questionnaire: ANOVA (two-sided P-values) (274 patients)
 

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Table 4. Functional scales according to age, follow-up period, tumor stage, primary surgical treatment, radiotherapy and cytotoxic therapy (274 patients)
 
Overall, the studied tumor and treatment associated variables and demographic factors had little impact on the functional scales. None of the tumor and treatment associated variables and demographic factors showed an impact on overall QoL, emotional functioning and cognitive functioning (P >0.05). The follow-up interval had a significant impact on physical functioning. Patients with a longer disease-free interval reported better physical functioning (86.1) in comparison to the other three subgroups with shorter intervals (80.9, 82.1, 76.7; P = 0.03). Considering the impact of radiotherapy as a covariate the significant impact of primary surgical therapy on physical functioning and social functioning was no longer observed (P = 0.25 and 0.55). An effect of adjuvant radiotherapy was observed on role functioning: patients assigned to receive adjuvant radiotherapy had higher scores in role functioning (71.8, P = 0.03) than those without radiotherapy (62. 9). The significant impact of radiotherapy on cognitive functioning and social functioning disappeared (P = 0.20 and 0.14) if the covariance of primary surgical treatment was considered in an ANCOVA. Social functioning was affected by age, tumor stage and cytotoxic therapy. Older patients reported better social functioning (85.6) compared with younger patients (78.2, P = 0.01). Patients with stage I disease had higher scores in the social functional scale (85.7) than patients with stage IIIB disease (61.1, P = 0.04). Women with cytotoxic therapy reported worse social functioning (76.3, P = 0.04) compared with women without cytotoxic therapy (83.2).

Impact of medical and demographic factors on additional psychological aspects of quality of life
Tables 5 and 6 summarize the impact of tumor and treatment associated variables and demographic factors on body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence in the follow-up examination. Table 5 shows the two-sided P-values of the ANOVA, Table 6 the mean values and SDs of the additional scales according to the observed independent factors.


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Table 5. Impact of medical and demographic factors on body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence: ANOVA (two-sided P-values) (274 patients)
 

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Table 6. Additional scales according to age, follow-up period, tumor stage, primary surgical treatment, radiotherapy and cytotoxic therapy (274 patients)
 
With the exception of the factors ‘cytotoxic therapy’ and ‘radiotherapy’, all tumor and treatment associated variables and demographic factors had an impact on at least one psychological parameter. Primary surgical treatment had the strongest impact and affected all four additional scales. Patients treated with mastectomy showed a significantly less favorable body image compared with those treated with BCT (37.5 versus 17.2, P <0.01), less satisfaction with primary surgical treatment (10.7 versus 4.0, P = 0.01) and less satisfaction with the cosmetic result (57.1 versus 75.5, P <0.01), but also reported less fear of recurrence (55.3 versus 63.9, P = 0.04). Tumor stage had a significant impact on body image and cosmetic result. Stage I was associated with the most favorable body image (20.6), stage IIIB with the least favorable (44.4, P = 0.04). Patients with stage I or IIA were pleased with the cosmetic result more frequently (71.0 and 74.3) than those with stage IIIB (38.9, P = 0.02). Age had a significant impact on cosmetic result and fear of recurrence. Younger patients reported a better cosmetic result (72.6, P = 0.04), but more fear of recurrence (64.4, P = 0.04) compared with older patients (64.6 and 55.8). Furthermore, there was an impact of the length of the disease-free interval on body image. Patients with a disease-free interval <1 year reported a significant better body image (16.2) than patients with a longer disease-free interval (26.5, 29.5, 27.0, P = 0.02). The significant impact of radiotherapy on body image, satisfaction with operation and cosmetic result was no longer observed (P = 0.40, 0.38 and 0.68) if analyses of covariance with primary surgical treatment as a covariate were conducted.


    Discussion
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
We analyzed the impact of tumor and treatment associated variables, as well as demographic factors, on different aspects of QoL in breast cancer patients after an average follow-up period of 4 years following primary surgical treatment. At the time of the follow-up examination, patients showed minor impairment of QoL and body image, but a considerable amount of fear of recurrence. None of the studied factors had a significant impact on overall QoL according to the QLQ-C30 questionnaire. In contrast, with the exception of the factors ‘cytotoxic therapy’ and ‘radiotherapy’ all investigated variables presented an impact on at least one of the additional psychological scales. Primary surgical treatment had the strongest impact and affected all four scales. Patients treated with BCT reported a more favorable body image compared to those treated with mastectomy, more satisfaction with surgical treatment, rated a better cosmetic result, but presented more fear of recurrence.

The QLQ-C30 questionnaire used in our study has been developed as a quantitative measure of health-related QoL for cancer patients [17]. Its validity has previously been well established [18]. We added scales to investigate important psychological aspects of QoL in breast cancer patients, neglected in the standardized questionnaire: body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence. Cronbach’s {alpha}-reliability, convergent and discriminative validity of our subscales were acceptable. The psychometric properties of the additional scales were established so far only within our sample. However, our study group aims at a broad validation of these scales in other clinical samples. In this retrospective, cross-sectional study the follow-up examination was assessed contemporaneously. Because of the retrospective study design and the fact that the surgery was not randomly assigned, our results should be interpreted with caution. The study’s use of (univariate) analysis of variance to test for associations between various oncological and psychological factors is in line with the methodology of international cancer clinical trials [1].

Results concerning long-term QoL in breast cancer patients are heterogeneous. Some studies find long-term negative changes of overall QoL and its dimensions [5, 8], others do not demonstrate a permanently and globally impaired QoL of breast cancer patients [7, 10]. In comparison to a sample of the general population without cancer disease [22], patients in our study showed similar overall QoL values. One reason for this observation might be that patients with stage IV tumors at time of primary diagnosis and recurrent breast cancer at time of follow-up examination were excluded. Rather, the vast majority of patients (74.4%) were diagnosed with stage I or IIA tumors. Yet, our sample presents impairments of QoL in comparison to the general population [22] concerning emotional functioning, fatigue and insomnia. One aim of our study was to analyze the psychological long-term impact of the primary surgical treatment. At the time of follow-up examination, body image was moderately impaired, satisfaction with surgical treatment was high and cosmetic results were rated favorably. Remarkably, the patients described a considerable amount of fear of recurrence despite their disease-free interval. In summary, our data suggest that 4 years after diagnosis tumor and primary treatment still influence patients’ life concerning fear and emotional coping.

Comparing the QLQ-C30 questionnaire and our self-implemented scales, we found a remarkable discrepancy between the two instruments. The studied tumor and treatment associated variables and demographic factors had no significant impact on overall QoL of the standardized questionnaire, but did have an impact on our additional scales. This leads us to two conclusions. First, our scales assess distinct constructs of QoL, not covered by the QLQ-C30 questionnaire. Secondly, our QoL factors might present a more breast cancer specific QoL concept in comparison to the QLQ-C30 questionnaire, including a more general health-related QoL concept. However, one has to keep in mind that other workers, including the EORTC study group, have developed scales specific to breast cancer, for example a breast cancer version of the Rotterdam Symptom Checklist [23], the Functional Assessment of Cancer Therapy—Breast [24] and the breast cancer module of the EORTC to be used in addition to the core questionnaire QLQ-C30 [25]. We did not use one of these standardized breast cancer modules because none of them covered the psychological variables we were interested in, in a sufficient and brief module.

The impact of two of the six studied factors on long-term QoL should be discussed in more detail: the time interval between primary diagnosis and follow-up examination, and the primary surgical treatment modality. Patients with a longer follow-up interval reported better physical functioning, whereas patients with a short interval described less body image problems, which is in line with other studies [8]. This observation might be explained by the nature of disease coping at the time of primary diagnosis, which predominantly addresses stress caused by life-threatening and adverse effects of primary therapy. Later on, psychological strains might increase, and thus the patient’s focus might shift increasingly towards body image problems.

Fallowfield and colleagues found comparable incidence of anxiety states or depressive illness in breast cancer patients irrespective of surgical treatment offered [26, 27]. In our study, in line with previous publications [3, 28, 29], the standardized QoL questionnaire failed to demonstrate a difference in long-term QoL between patients receiving BCT or mastectomy. However, primary surgical treatment modality still strongly influences a patient’s life. Patients with BCT reported better physical and social functioning, better body image, more satisfaction with surgical treatment and perceived the cosmetic result more positively. Yet, these patients significantly reported more fear of recurrence. The superiority of BCT in terms of body image and satisfaction with treatment is in line with the majority of publications [3, 6, 27, 29], while the question of differences in fear of recurrence between the two subgroups is discussed controversially [11, 30, 31]. In summary, the results of our study confirm that the advantages of BCT prevail even several years after primary diagnosis.

Overall, the impact of oncological and demographic factors on QoL in breast cancer patients is discussed heterogeneously with partly contradicting conclusions. This may be explained by methodological differences between the studies. The variety of measuring instruments and the array of different components of the QoL construct result in difficulties in comparing different studies [1, 29]. Current measurement tools should be required to give physicians and cancer patients clinically relevant information about daily care, assist them in therapeutic decision-making and in identifying the needs concerning psychosocial interventions [2, 9]. Combining the standardized QoL concepts with breast cancer specific psychological variables, namely body image, fear, satisfaction with treatment and cosmetic evaluation, may improve the ability to meet these requirements.

This is the first study to have used the QLQ-C30 questionnaire in conjunction with supplementary psychological scales to analyze the impact of various tumor and treatment associated variables and demographic factors on long-term QoL within one trial. In summary, our results support the hypothesis that current QoL questionnaires do not sufficiently cover breast cancer specific aspects of QoL.


    Footnotes
 
+ Correspondence to: Dr K. Härtl, Department of Gynecology and Obstetrics, Klinikum der Ludwig-Maximilians-Universität München, Maistrasse 11, 80337 Munich, Germany. Tel: +49-89-5160-4139; Fax: +49-89-5160-4186; E-mail: kristin.haertl{at}fk-i.med.uni-muenchen.de Back


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 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
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