Breast-conserving surgery is now commonly used in the treatment

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1 2260 The Effects of Radiation Therapy on Quality of Life of Women with Breast Carcinoma Results of a Randomized Trial Timothy J. Whelan, B.M., B.Ch., M.Sc. 1,2,3 Mark Levine, M.D. 2,3 Jim Julian, M.Math. 3 Peter Kirkbride, M.D. 4,5 Peter Skingley 3 for the Ontario Clinical Oncology Group 1 Cancer Care Ontario, Hamilton Regional Cancer Centre, Hamilton, Ontario, Canada. 2 Department of Medicine, McMaster University, Hamilton, Ontario, Canada. 3 Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada. 4 Ontario Cancer Institute, Princess Margaret Hospital, Toronto, Ontario, Canada. 5 University of Toronto, Toronto, Ontario, Canada. Presented at the 39th Annual Meeting of the American Society for Therapeutic Radiology and Oncology, Orlando, Florida, October 19 23, Other members of the Ontario Clinical Oncology Group are as follows: P. B. McCulloch, Cancer Care Ontario (CCO) Hamilton Regional Cancer Centre, Hamilton; M. Lipa, Toronto Hospital, Toronto; L. J. Mahoney, St. Michael s Hospital, Toronto; B. D. Nair, CCO Ottawa Regional Cancer Centre, Ottawa; F. Perera, CCO London Regional Cancer Centre, London; C. S. Wong, Ontario Cancer Institute, Princess Margaret Hospital, Toronto; Ontario, Canada. This study was performed at the Hamilton Civic Hospitals Research Centre, McMaster University, Hamilton, Ontario, Canada. Address for reprints: Timothy J. Whelan, B.M., B.Ch., M.Sc., Hamilton Regional Cancer Centre, 699 Concession Street, Hamilton ON L8V 5C2, Canada. Received July 14, 1999; revision received December 23, 1999; accepted January 21, BACKGROUND. The purpose of this study was to evaluate the effect of breast irradiation on quality of life, including cosmetic outcome, for patients enrolled in a clinical trial. METHODS. Between 1984 and 1989, a randomized trial was conducted in Ontario, Canada, in which women with lymph node negative breast carcinoma who had undergone lumpectomy and axillary lymph node dissection were randomized to either breast irradiation or no further treatment. A modified version of the Breast Cancer Chemotherapy Questionnaire (BCQ) was administered to women at baseline, 1 month (4 weeks), and 2 months (8 weeks) after randomization. Irritation of the skin of the breast, breast pain, and appearance of the breast to the patient were also assessed every 3 months for the first 2 years of the study. RESULTS. Of 837 patients, 416 were randomly allocated to radiation therapy and 421 to no further treatment. The mean change in quality of life from baseline to 2 months was 0.05 for the radiation group and 0.30 for the control group. The difference between groups was statistically significant (P ). Longer term radiation therapy increased the proportion of patients who were troubled by irritation of the skin of the breast and breast pain. Radiation therapy did not increase the proportion of patients at 2 years who were troubled by the appearance of the treated breast; 4.8% in irradiated and nonirradiated patients (P 0.62). CONCLUSIONS. Breast irradiation therapy had an effect on quality of life during treatment. After treatment, irradiated patients reported increased breast symptoms compared with controls. However, no difference was detected between groups at 2 years in the rates of skin irritation, breast pain, and being upset by the appearance of the breast. Cancer 2000;88: American Cancer Society. KEYWORDS: randomized trial, breast neoplasm, radiation therapy, quality of life. Breast-conserving surgery is now commonly used in the treatment of women with early stage breast carcinoma. 1,2 Five published randomized trials have demonstrated that breast irradiation after surgery substantially reduces the risk of recurrence of carcinoma in the breast. 3 7 In the Ontario trial, women with lymph node negative breast carcinoma treated by lumpectomy and axillary lymph node dissection were randomized to breast irradiation or no further treatment after surgery. 5 At a median follow-up of 7.6 years, the risk of local recurrence was reduced from 35% in nonirradiated patients to 11% in irradiated patients. No difference was detected in overall survival. Based on the results of these and other clinical trials, breast irradiation is commonly offered to women after lumpectomy to prevent local recurrence and the need for mastectomy American Cancer Society

2 Quality of Life with Breast Irradiation/Whelan et al Breast irradiation usually is given daily, except weekends, for weeks. It is associated with recognized short term side effects (within 3 months of completion of treatment) of fatigue and skin erythema, and more medium and long term side effects (3 months to 3 years after treatment) of breast edema, pain, fibrosis, and telangiectasia. 8 Many of the long term side effects are thought to impinge on cosmetic outcome. Recently in health care, there has been increased recognition of the need to measure the effects of treatment on a patient s quality of life. Quality of life refers to the wide variety of subjective experiences (such as symptoms, physical function, emotional function, and social function) that are related to health. 9 In clinical decision making, the benefits of radiation therapy in preventing local recurrence must be weighed against the impact of treatment on a patient s quality of life. Previous studies of patients treated by mastectomy have suggested that the addition of postoperative radiotherapy was associated with a higher incidence of psychologic morbidity, such as depression and anxiety. 10,11 Studies of breast-conserving therapy (lumpectomy plus breast irradiation) also have suggested that this treatment as compared with mastectomy or lumpectomy alone may be associated with an increase in affective symptoms. 12,13 Other studies have not shown an effect of postoperative radiation therapy on psychologic distress but have suggested significant effects on physical symptoms, in particular, fatigue Many of these studies have involved small numbers of patients, nonrandomized comparisons and multiple end points increasing the possibility of falsely attributing observed differences to the effect of treatment. The purpose of this study was to evaluate the effect of breast irradiation after lumpectomy on quality of life and cosmetic outcome in women with axillary lymph node negative breast carcinoma in a randomized controlled trial. METHODS Details of the study design have been published previously 17 but are outlined briefly. From April 1984 through to February 1989, consecutive patients with breast carcinoma treated by lumpectomy and axillary lymph node dissection who had been referred to the Princess Margaret Hospital in Toronto or the Ontario Cancer Treatment and Research Foundation Regional Cancer Centres in Hamilton, London, Ottawa, Windsor and Thunder Bay, Ontario, Canada were approached for study entry. Eligibility criteria required that the tumor be 4 cm in diameter, that local excision was microscopically complete, and that there was no evidence of histologic involvement of axillary lymph nodes. Informed consent was obtained from eligible patients before randomization. Eligible patients who agreed to participate were randomized to receive local breast irradiation or no further treatment. Patients assigned to radiation therapy received a dose of 40 gray (Gy), given by cobalt-60 over a period of 3 weeks with 16 daily fractions to the entire breast. Subsequently, a boost was given to the primary site using a direct field to give a dose of 12.5 Gy in 5 daily fractions. The breast was irradiated by a means of a parallel opposed pair of tangential, partially wedged fields. Bolus material was not used. Radiation therapy was delivered daily, Monday to Friday. Patients did not receive postoperative adjuvant systemic therapy. Quality of Life Acute phase (0 2 months after randomization) A modified version of the Breast Cancer Chemotherapy Questionnaire (BCQ) 18 containing 17 items (questions) was administered by a nurse. The BCQ is a disease specific instrument for measuring quality of life in patients with breast carcinoma and previously has been shown to be valid and reliable. 18 The original instrument, composed of 30 items, was based on the physical, emotional, and social problems identified by women receiving adjuvant chemotherapy for breast carcinoma. In the modified version, 15 items specific to chemotherapy were omitted, and 2 items specific to radiation therapy were added. These items were developed using a similar methodology to that used to develop the original questionnaire. A preliminary list of items considered likely to be important to women receiving breast irradiation was generated through a review of the literature, consultation with radiation oncologists and nurses, and structured interviews with axillary lymph node negative breast carcinoma patients. Two items (questions) were selected based on the frequency with which they were reported and the importance attributed to the item by patients. The first item was How much of the time during the past 2 weeks have you been troubled by pain, itchiness, or discomfort of the skin of your chest? with responses on a Likert scale from 1 (all of the time) to 7 (none of the time). The second item was How much trouble or inconvenience have you had during the past 2 weeks as a result of not being able to bathe or wash your chest? with responses on a Likert scale from 1 (a great deal of trouble or inconvenience) to 7 (no trouble or inconvenience). Hence, the version of the BCQ used in our study contained 6 domains including emotional dysfunction (6 items), social support (2 items), attractiveness (1 item), fatigue (5 items), physical symptoms (2 items),

3 2262 CANCER May 15, 2000 / Volume 88 / Number 10 and inconvenience (1 item). Each item was answered on a 7-point Likert scale, and the mean score of all items represented a summary score for overall quality of life. The BCQ was administered to women at baseline, 1 month (4 weeks) and 2 months (8 weeks) after randomization. Long term phase (3 months to 2 years after randomization) Originally, we intended to administer the BCQ every 3 months for the first 2 years after randomization, but this turned out to be logistically impractical. Three items regarding irritation of the skin, breast pain, and appearance of the breast to the patient were modified from the original instrument. Specifically, 3 questions were asked: 1. During the past 2 weeks, have you been troubled by pain, itchiness, or discomfort of the skin of your chest? 2. During the past 2 weeks, have you been troubled or inconvenienced as a result of pain in the breast that was operated on? 3. During the past 2 weeks, have you been troubled or upset as a result of feeling upset that the breast that was operated on is unattractive? Each of the items had a 4-point Likert scale ranging from 1 (not at all) to 4 (very often). Items were administered every 3 months for the first 2 years of the study. Statistical Methods Acute quality of life In the acute phase after randomization, quality of life scores were calculated for each patient for the entire 17-item BCQ instrument and for the 6 individual domains as means of the available responses. Mean change scores for each subject were calculated by subtracting the baseline response from the 2 postrandomization scores. Only patients who completed the questionnaires at baseline, 1 month, and 2 months were included in this analysis. Repeated measures mixed models were used to compare the effect of treatment on quality of life and to account for correlated within-person responses. 19 Various covariance structures were considered using SAS (version 6.12) PROC MIXED. In the model fitting stage, a nominal P value of 0.01 was used to determine statistical significance in view of the multiple comparisons performed. Previous studies using similarly derived instruments to measure quality of life associated with asthma and chronic lung disease have demonstrated that mean differences of 0.5, 1, or 1 on a 7-point Likert scale have been associated with small, moderate, or large changes, respectively, in patients reported quality of life To help interpret the differences observed in overall quality of life measured, we compared the proportion of patients who had deterioration in mean BCQ score 0.5 at 2 months relative to baseline for the control and radiation groups by using the chi-square test. Long term quality of life In the long term phase, the responses to the three 4-point scale questions at 3-month intervals over the 2 years after randomization were dichotomized. A response of 3 (occasionally) or 4 (very often) translated into a negative outcome, whereas a 2 (rarely) or 1 (not at all) answer was considered to be positive for each of the three questions on irritation of the skin of the breast, breast pain, and appearance of the breast to the patient. The data were summarized in terms of percent of patients with a negative response. All of the available long term data were used in this analysis. Like the acute phase data, repeated measures mixed models were used to compare the effect of treatment on irritation of the skin of the breast, breast pain, and appearance of the breast to the patient and to account for the within-person correlation. 19 Unlike the methods used for continuous measures, generalized linear models were fitted to the dichotomized outcomes using SAS (version 6.12) PROC GENMOD using the Generalized Estimating Equations (GEE) method of estimation. As above, P values 0.01 were declared statistically significant. RESULTS Eight hundred thirty-seven patients were randomly allocated to receive either radiation (n 416) or no radiation therapy (n 421). The treatment groups were comparable in terms of baseline characteristics, such as age, tumor size, nuclear grade, and levels of estrogen and progesterone receptors. 15 Acute Quality of Life Quality of life data at baseline, 1 month, and 2 months were available for 91% of patients. Fifty-seven percent of patients started radiation within 2 weeks of randomization. Thus, at the time of the 1 month assessment, 95% of patients were on treatment, and 56% had completed 2 weeks of treatment. By the 2 month assessment, 88% of patients had completed radiation, and 58% of patients were more then 2 weeks from the last radiation treatment. The mean BCQ score over time for patients in both treatment groups is described in Figure 1. In the control group, there was a steady increase in quality of life from baseline to 2 months

4 Quality of Life with Breast Irradiation/Whelan et al TABLE 2 Mean Change Score (t 2 t 0 ) at 2 Months by Domain Treatment groups Domain Radiation (n 344) Control (n 376) Difference P value Emotional dysfunction Social support Attractiveness Fatigue a Physical symptoms a Inconvenience a Overall score a a Statistically significant (P 0.01). FIGURE 1. Mean BCQ score over time and 95% confidence intervals are shown. BCQ: Breast Cancer Questionnaire. TABLE 1 Mean Change Score (t 1 t 0 ) at 1 Month by Domain Domain Treatment groups Radiation (n 344) Control (n 376) Difference P value Emotional dysfunction Social support Attractiveness Fatigue a Physical symptoms a Inconvenience a Overall score a a Statistically significant (P 0.01). after randomization likely representing patients recovering from the effects of diagnosis and surgery. In the radiation group, the mean score decreased minimally at 1 month and remained relatively unchanged at 2 months. In terms of mean change score from baseline, at 1 month, the control group increased to 0.21 whereas the radiation group decreased by 0.07 (Table 1). Similarly, at 2 months, the control group increased by 0.30, and the radiation group decreased by 0.05 (Table 2). The difference between groups was statistically significant for both time periods (P ). To reexamine the effect on individual domains, we looked at the mean change score from baseline for each domain (Table 1). At 1 month, statistically significant differences in mean change scores were noted for the fatigue, physical, and inconvenience domains. No differences were noted for the emotional, social, and attractiveness domains. A similar pattern was observed for the change scores between baseline and 2 months after randomization (Table 2). The proportion of patients who had a deterioration in mean BCQ score of 0.5 at 2 months relative to baseline was compared for the control and radiation groups. Ninety-three of 344 patients (27%) in the radiation group experienced a deterioration in quality of life of this magnitude, whereas only 60 of 376 patients (16%) in the control group experienced a similar deterioration (P ). Long Term Quality of Life Approximately 75% of patients responded to the 3 separate items administered during the 2 years after randomization. The 3-month (12 week) assessment was performed at a median of 7 weeks after the last radiation treatment (25 75%, range weeks). Radiation increased the proportion of patients who reported being troubled by skin irritation. This was most evident at the 3-month assessment, 28% in the radiation group versus 14% in the control group (P ) (Fig. 2). The number of patients who reported skin irritation decreased over time in both groups (P for trend) so that by 24 months only 7% in each group reported this symptom. With respect to breast pain (Fig. 3), a similar pattern was observed. Radiation therapy increased the number of patients who were troubled by breast pain. This was most evident at 6 months after randomization in which 33% of patients in the radiation group versus 20% in the control group reported this problem (P ). Again, reporting of this symptom decreased over time (P for trend), and at 24 months approximately 15% of patients in both groups reported breast pain. With respect to trouble or upset regarding the

5 2264 CANCER May 15, 2000 / Volume 88 / Number 10 FIGURE 2. Percentage of patients reporting irritation of the skin of the breast by treatment group is shown. FIGURE 3. Percentage of patients reporting breast pain by treatment group is shown. appearance of the breast to the patient (Fig. 4), this was reported less frequently, and no difference was detected between groups; 4.8% of patients in each group reported this problem at 2 years (P 0.62). DISCUSSION In view of the increasing use of breast-conserving therapy, we were interested in determining the additional morbidity associated with breast irradiation from the patient s perspective. Whereas some studies have suggested that patients may suffer from anxiety, depression, 12,13 and fatigue 16 in addition to local physical side effects of radiation therapy, other studies have not shown this effect. 15 Our results demonstrate a difference in overall quality of life between irradiated and nonirradiated patients during the acute period. Note that most of the data informing acute quality of life were collected during or shortly after radiation therapy. The difference in mean change scores between groups was 0.27 and 0.35 on a 7-point Likert scale at 1 and 2 months after randomization, respectively. When we looked at differences in a mean change score by domain, no differences were detected between groups for the domains of emotional dysfunction, social support, and attractiveness. Statistically significant differences were observed for the domains of physical symptoms, inconvenience, and fatigue. The differences in these 3 latter domains were primarily responsible for the differences observed in the overall quality of life score for the acute phase. The differences in these domains are consistent with clinical experience that breast irradiation is associated FIGURE 4. Percentage of patients reporting trouble or upset regarding the appearance of the breast by treatment group. with local physical symptoms and fatigue. These results also suggest that radiation has little effect on emotional and social well-being (aside from inconvenience). Although the differences in overall acute quality of life between groups were statistically significant, the question arises whether these differences are important to patients. Investigators have demonstrated that mean differences of 0.5, 1, or 1 in mean score on a 7-point Likert scale are associated with small, moderate, and large changes, respectively, in patients reported quality of life in asthma and chronic lung disease Similar differences using other quality of life measures also have been associated with important changes in cancer patients reported quality of life. 23 Using these values as a guide, we might interpret the

6 Quality of Life with Breast Irradiation/Whelan et al differences detected in this study between groups in overall quality of life as not important. If, however, we look at the number of patients who had a small but important deterioration in quality of life during the acute phase (over the 2-month period from randomization), a greater number of patients treated with radiation therapy deteriorated as compared with the controls. This suggests that whereas the overall mean difference in acute quality of life detected does not appear meaningful, 1 in 10 patients had an important deterioration in quality of life as a result of treatment. This type of information may be useful for physicians and patients when discussing the effect of breast irradiation after lumpectomy and for treatment decision making. Overall quality of life improved in the control group from baseline to 2 months whereas there was little change in quality of life in the radiation group over this 2-month period. The observed difference between groups may be due either to a more rapid resolution of postoperative effects in the control patients or to specific side effects associated with radiation therapy. It is likely that both factors are involved. Unfortunately, we do not have definitive overall quality of life data beyond the limited 2-month period to state that the observed early difference between groups resolves over time. However, we anticipate that irradiated patients ultimately attain the same quality of life as patients who did not receive radiation. This is supported by the observed decrease in the number of patients reporting symptoms of skin irritation and breast pain after radiation treatment. Results from the three items measured long term suggest that skin irritation and breast pain attributed to radiation therapy may be reported up to 3 6 months after initiation of treatment. It is important to note that these symptoms were also present in nonirradiated patients and continue to exist in a small proportion of patients up to 2 years after treatment. In previous studies of breast-conserving therapy, cosmetic outcome often has been assessed by an observer, usually a physician. The cosmetic outcome usually is scored excellent, good, fair, or poor The overall objective of our study was to examine the impact of radiation treatments on a patient s quality of life. We used a patient-based approach to develop a questionnaire to assess the impact of cosmetic outcome on quality of life. This questionnaire is not comparable to previous cosmetic rating scales and can be considered similar to quality of life instruments assessing appearance and body image. Other studies have reported on factors associated with patients satisfaction with cosmetic outcome. Our study was not designed to look specifically at factors that affect a woman s feelings about breast appearance, but presumably factors associated with patient satisfaction with cosmetic outcome, e.g., breast size and shape, contribute to this outcome. 26 Concern regarding the appearance of the breast was reported equally by both groups and tended to decrease over time. Breast irradiation delivered with relatively modern techniques did not result in an important deterioration in cosmetic outcome from the patient s perspective during the 2-year follow-up. These observations are reassuring because many of the late effects of radiation injury may be evident by this time. 27 As late sequelae of radiation may progress beyond 2 years, further follow-up will be necessary to be confident about this observation. This study is unique in that it represents the first randomized trial to our knowledge to report the quality of life associated with breast irradiation after lumpectomy in a large number of patients. However, some conditions should be noted. Radiation therapy to the whole breast and boost therapy were delivered with cobalt-60 at 2.5 Gy per fraction. This approach is not commonly used throughout North America at the current time; however, the results are likely to be generalizable to more conventionally used treatment strategies and fractionation schedules. 27 Unfortunately, detailed quality of life information was available only for the first 2 months of follow-up and other indices for only 2 years. Results from the BCQ indicate that differences in quality of life between radiation and control groups can be detected up to 2 months after randomization. Results from the single items administered for 2 years suggest that this effect may be more prolonged. In future studies, more detailed information regarding the longer term impact of treatment on patients overall quality of life would be useful. In summary, our results demonstrate that radiation therapy did impact on the quality of life of women with early breast carcinoma during treatment. After completion of treatment, irradiated patients reported increased breast symptoms compared with nonirradiated patients. These differences decreased over time. REFERENCES 1. Nattinger AB, Gottlieb MS, Veum J, Yahnke D, Goodwin JS. Geographic variation in the use of breast-conserving treatment for breast cancer. N Engl J Med 1992;326: Iscoe NA, Goel V, Wu K, Fehringer G, Holowaty EJ, Naylor CD. Variation in breast cancer surgery in Ontario. Can Med Assoc J 1994;150:

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