Sample
From the 436 patients on endocrine treatment originally surveyed in 2009-11, 27 patients (6.2%) have deceased, this corresponds to an OS of 93%. A total of 290 breast cancer long-term survivors participated in the follow-up study. The remaining 119 patients did either not agree to fill out questionnaires because of personal reasons (11.9%) or could not be contacted due to logistic reasons (15.4%). Hence, a response rate of 70% could be achieved.
Among the patients in the final analysis, a total of 8% reported a relapse (3.4% in the AI group and 4.5% in the tamoxifen group). We excluded those patients from the further analysis to provide group homogeneity. Hence, we report data of a final sample of 268 BCS. Please find details in the flow chart below.
Patients participated after a median follow-up period of 8 years (range 6–9 years; mean = 8.02). At the time of the follow-up assessment, patients were aged 65 years on average and 90% were postmenopausal. Patients who had received tamoxifen were significantly younger than patients with AI therapy (p < 0.001) as tamoxifen has been the first-line ET for premenopausal patients at the time the original study was performed (and AIs for postmenopausal patients). Details on clinical data are presented in Table 1.
Table 1
Clinical patient data (n = 268) at follow-up
| Patients with AI treatment N = 159 | Patients with tamoxifen treatment N = 109 | All BCS N = 268 |
| Frequency (%) | Frequency (%) | Frequency (%) |
Age at follow-up | Mean (SD) Range | 72.8 (SD 7.2) years# 56–94 | 54.5 (SD 5.3) years# 36–68 | 65.3 (SD 11) years (36–94 years) |
Time since diagnosis | Median (SD) Mean Range | 10.4 (SD 2) years 10.9 years 7–17 years | 9.2 (SD 1.3) years 9.4 years 7–13 years | 10 (SD 1.9) years 10.3 (SD 1.9) years 7-17.6 years |
Time between assessments | Median (SD) Mean Range | 8.2 (SD 0.5) years 8.2 years 6.9-9 years | 7.9 (0.6) years 7.8 years 6.4–9.10 years | 8 (SD 0.6) years 8 years 6.4–9.1 years |
Time between ET termination and follow-up | Median (SD) Mean Range | 4.93 (SD 2) years 4.9 years ongoing − 9 years | 3.8 (SD 1.8) years 3.9 years ongoing − 8 years | 4.5 (SD 2) years 4.4 (SD 2) years ongoing − 9 years |
Menopausal state | Premenopausal postmenopausal | -- 159 (100%) | 27 (25%) 81 (75%) | 27 (10%) 240 (90%) |
Overall duration of adjuvant endocrine therapy (months) Treatment duration – groups ET intake ET ongoing at follow-up | Mean (SD) Range < 5 years Regular 5 years Extended yes | 5.8 (SD 1.9) years 2.7–15 years 10 (6.4%) 110 (70.1%) 37 (23.5%) 7 (4.4%) | 5.3 (SD 1.7) years 1.7–13 years 16 (14.8%) 76 (70.4%) 16 (14.8%) 8 (7.3%) | 5.5 (1.8) years 1.7–15 years 26 (10%) 186 (70%) 53 (20%) 15 (5.6%) |
# Significant difference between patients treated with tamoxifen vs. AIs regarding age (p < 0.001) |
Table 1 Clinical patient data (n = 268) at follow-up
# Significant difference between patients treated with tamoxifen vs. AIs regarding age (p < 0.001)
Changes of ET related toxicity
We observed a significant improvement of the overall endocrine symptomatology in the long-term (FACT-ES baseline mean = 59 vs. follow-up mean = 62, p < 0.001); this significant improvement was found for both, patients who had received tamoxifen (FACT-ES baseline mean = 58.4 vs. follow-up mean = 61.2) as well as those with previous AI treatment (FACT-ES baseline mean = 59.7 vs. follow-up mean = 62.7).
In detail, vasomotor symptoms including hot flashes and cold/night sweats decreased significantly with time in both groups. In contrast, gynecologic symptoms did not change over time except for vaginal discharge, which decreased significantly; loss of interest in sex even increased in long-term in percentages. Interesting to note, of the overall sample 9.3% did not complete both questions on sexuality and 20.7% answered only one of both questions (i.e. pain with intercourse and loss of interest in sex) at the second assessment.
No significant change over time was observed for gastrointestinal symptomatology; a total of 38.4% and 30.4% of patients reported persistent weight problems in the tamoxifen and AI group, respectively. Finally, the typically ET-related symptoms joint pain, lack of energy and mood swings were highly prevalent at the follow-up assessment time point. Details are presented in Tables 2–4.
Table 2
Prevalence physical and psychological symptoms in BCS (entire sample)
| All BCS N = 268 |
| 1st assessment | Follow-up | Difference in % |
Median time since diagnosis | 1.9 (SD 1.7) years | 10.0 (SD 1.9) years | |
| % (CI95%) | % (CI95%) | |
Vasomotor symptoms | | | |
Hot flashes | 68.7% (62–74) | 39.5% (33–46)* | -29.2% |
Cold sweats | 30.0% (24–36) | 16.3% (12–21)* | -13.7% |
Night sweats | 47.0% (40–53) | 24.3% (19–30)* | -22.7% |
Sleeping difficulties | 14.9% (11–20) | 9.5% (6–14)# | -5.4% |
Gynecologic symptoms | | | |
Vaginal discharge | 12.4% (9–17) | 4.6% (2–8)* | -7.8% |
Bleeding or spotting | 1.6% (0.5-4) | 1.4% (0.3-4) | -0.2% |
Vaginal itching/irritation | 9.8% (6–14) | 10.3% (7–14) | + 0.5% |
Vaginal dryness | 30.2% (25–36) | 33.0% (27–39) | + 2.8% |
Breast sensitivity/tenderness | 24.4% (19–30) | 19.1% (14–24) | -5.3% |
Pain or discomfort with intercourse | 16.5% (12–22) | 20.5% (15–27) | + 4% |
Lost interest in sex | 40.4% (34–46) | 48.7% (42–55)* | + 8.3% |
Gastrointestinal symptoms | | | |
Weight gain | 36.8% (31–43) | 33.9% (28–40) | -2.9% |
Emesis | 1.2% (0–3) | 0.9% (0–2) | -0.3% |
Diarrhea | 5.2% (3–9) | 5.8% (3–10) | + 0.6% |
Feeling bloated | 14.7% (11–19) | 9.5% (6–14) | -5.2% |
Nausea | 4.5% (2–8) | 3.6% (2–7) | -0.9% |
Pain | | | |
Headaches | 16.4% (12–21) | 14.7% (10–20) | -1,7% |
Joint pain | 45.5% (40–51) | 44.2% (38–50) | -1.3% |
Psychological symptoms | | | |
Feeling lightheaded (dizziness) | 13.9% (10–19) | 13.9% (10–19) | -- |
Mood swings | 36.8% (31–43) | 30.2% (24–36)* | -6.6% |
Being irritable | 30.6% (25–36) | 27.5% (22–33) | -3.1% |
Lack of energy | 36.4% (30–42) | 33.8% (28–40) | -2.6% |
*Significant difference on a p < 0.01 (based on the Sign Test) |
#Significant difference on a p < 0.05 (based on the Sign Test) |
Table 3
Prevalence physical and psychological symptoms in BCS having received ET with tamoxifen
| Patients with TAM treatment N = 159 |
| 1st assessment | Follow-up | Difference in % |
Median time since diagnosis | 1.2 (SD 1.0) years | 9.2 (SD 1.3) years | |
| % (CI95%) | % (CI95%) | |
Vasomotor symptoms | | | |
Hot flashes | 83.8% (75–89) | 50.0% (40–59)* | -33.8% |
Cold sweats | 39.6% (30–49) | 21.6% (14–30)* | -18.0% |
Night sweats | 60.6% (51–69) | 29.9% (21–39)* | -30.7% |
Sleeping difficulties | 14.2% (8–22) | 5.9% (2–12)* | -8.3% |
Gynecologic symptoms | | | |
Vaginal discharge | 25.0% (17–34) | 5.2% (2–12)* | -19.8% |
Bleeding or spotting | 3.8% (1–9) | 2.1% (0–7) | -1.7% |
Vaginal itching/ irritation | 14.3% (8–22) | 13.3% (7–21) | -1% |
Vaginal dryness | 21.9% (15–30) | 35.1% (26–45)# | + 13.2% |
Breast sensitivity/ tenderness | 21% (14–29) | 19.4% (13–28) | -0.6% |
Pain or discomfort with intercourse | 14.4% (8–22) | 21.5% (14–31) | + 7.1% |
Lost interest in sex | 21.4% (14–30) | 34.7% (26–44)# | + 13.3% |
Gastrointestinal symptoms | | | |
Weight gain | 37.5% (29–47) | 38.4% (29–48) | + 0.9% |
Emesis | 1.0% (0–5) | 0.0% (0) | -1% |
Diarrhea | 2.9% (0.6-8) | 3.0% (0.6-8) | -0.1% |
Feeling bloated | 14.3% (8–22) | 10.2% (5–18) | -4.1% |
Nausea | 3.9% (1–10) | 2.1% (0–7) | -1.8% |
Pain | | | |
Headaches | 13.3% (8–21) | 12.1% (7–20) | -1.2% |
Joint pain | 30.5% (22–40) | 35.1% (26–45) | + 4.6% |
Psychological symptoms | | | |
Feeling lightheaded (dizziness) | 8.6% (4–15) | 6.1% (3–19) | -2.5% |
Mood swings | 38.2% (30–48) | 34.0% (25–44) | -4.2% |
Being irritable | 34.6% (26–44) | 25.8% (18–35) | -8.8% |
Lack of energy | 32.7% (24–42) | 27.5% (20–37) | -5.2% |
*Significant difference on a p < 0.01 (based on the Sign Test). |
#Significant difference on a p < 0.05 (based on the Sign Test) |
Table 4
Prevalence physical and psychological symptoms in BCS having received ET with aromatase inhibitors
| Patients with AI treatment N = 109 |
| Baseline | Follow-up | Difference in % |
Median time since diagnosis | 2.2 (SD 1.9) years | 10.4 (SD 2) years | |
| % (CI95%) | % (CI95%) | |
Vasomotor symptoms | | | |
Hot flashes | 57.8% (49–65) | 31.2% (23–39)* | -26.6% |
Cold sweats | 23.2.% (17–30) | 12.1% (7–19)* | -11.1% |
Night sweats | 37.4% (30–45) | 19.8% (13–27)* | -17.4% |
Sleeping difficulties | 15.4% (10–22) | 12.4% (7–19) | -3% |
Gynecologic symptoms | | | |
Vaginal discharge | 3.4% (1–8) | 4.1% (1–9) | + 0.7% |
Bleeding or spotting | 0.0% (0) | 0.8% (0–5) | + 0.8% |
Vaginal itching/ irritation | 7.5% (4–13) | 7.1% (3–13) | -0.4% |
Vaginal dryness | 36.1% (28–44) | 31.5% (24–40) | -4.6% |
Breast sensitivity/ tenderness | 26.9% (20–34) | 18.9% (12–27)# | 8% |
Pain or discomfort with intercourse | 18.3% (12–26) | 19.6% (13–29) | + 1.3% |
Lost interest in sex | 55.3% (46–63) | 61.5% (52–70) | + 6.2% |
Gastrointestinal symptoms | | | |
Weight gain | 36.3% (29–44) | 30.4% (23–39) | -5.9% |
Emesis | 1.4% (0–5) | 1.6% (0–6) | + 0.2% |
Diarrhea | 6.9% (3–12) | 8.0% (4–14) | + 1.1% |
Feeling bloated | 15.1% (10–21) | 9.0% (5–15) | -6.1% |
Nausea | 4.9% (2–10) | 4.6% (2–9) | -0.3% |
Pain | | | |
Headaches | 18.6% (13–25) | 16.7% (11–24) | -1.9% |
Joint pain | 56% (48–63) | 51.2% (42–60) | -4.8% |
Psychological symptoms | | | |
Feeling lightheaded (dizziness) | 17.7% (12–25) | 20.0% (14–28) | + 2.3% |
Mood swings | 35.8% (28–43) | 27.2% (20–35) | -8.6% |
Being irritable | 27.7% (21–35) | 28.8% (21–37) | + 1.1% |
Lack of energy | 38.9% (31–47) | 38.5% (30–47) | -0.4% |
*Significant difference on a p < 0.01 (based on the Sign Test) |
#Significant difference on a p < 0.05 (based on the Sign Test) |
Regarding the effect of age - independent from the treatment received - on symptom change over time, we found no difference for most symptoms across age groups (results not shown) with the exception of vaginal discharge (p < 0.001), headaches (p = 0.023) and mood swings (p < 0.001) (details in Table 5).
Table 5
Mean symptom difference from baseline to follow-up across age groups (significant results p < 0.05)
Symptoms | vaginal discharge mean difference (SD) | Headaches mean difference (SD) | mood swings mean difference (SD) |
< 50 years | -1 (1.13) | -0.3 (0.9) | -0.9 (1.6) |
50–59 years | -0.4 (0.9) | 0.12 (0.9) | -0.014 (1.6) |
60–69 years | -0.23 (0.7) | -0.35 (0.9) | 0.54 (1.7) |
>=70 years | 0.03 (0.5) | -0.04 (0.9) | 1 (1.5) |
QOL outcome
Overall, QOL according to the FACT-global score was significantly higher in long-term BCS compared to QOL in patients on ET-treatment (mean baseline = 88.3 vs. mean follow-up = 90.9, p = 0.011). This was true for patients who had received tamoxifen (mean baseline = 89.3 vs. mean follow-up = 92.8) as well as those with previous AI treatment (mean baseline = 87.5 vs. mean follow-up = 89.5). However, in terms of clinical relevance the improvement seems to be minor [21].
BCS reported significantly higher levels of physical well-being (FACT-physical well-being baseline = 23.9 mean vs. follow-up mean = 24.8, p < 0.01) and functional well-being (FACT-functional well-being baseline mean = 21.7 vs. follow-up mean = 22.7, p = 0.013) than patients on ET-treatment. For functional well-being, we observed a trend towards a higher increase in patients who had received tamoxifen, i.e. in the younger patient group (interaction effect p = 0.079) compared to patients in the AI-group.
No changes were observed for emotional well-being (FACT-emotional well-being baseline = 19.7 mean vs. follow-up mean = 20, p > 0.05) and social well-being (FACT-emotional well-being baseline mean = 22.5 vs. follow-up mean = 22.5, p > 0.05) (Fig. 2). This was true for both ET groups.