The Impact of Bariatric Surgery on Breast Cancer Recurrence: Case Series and Review of Literature

Abstract

Background
Excess body weight has been associated with worsening breast cancer survival. While bariatric surgery has been associated with less incident of breast cancer, the role that bariatric surgery plays after breast cancer diagnosis in terms of both feasibility and in preventing breast cancer recurrence is unclear.

Methods
We report the outcomes of 13 individuals who underwent bariatric surgery after definitive breast cancer treatment at a single institution.

Results
Thirteen females diagnosed with breast cancer (69.2% stage I, 23.1% stage II) at a median age of 42 years received bariatric surgery between 2001 and 2017. The median age of bariatric surgery was 52 years. Of the 13 patients, 46.2% underwent laparoscopic Roux-en-Y gastric bypass and 38.5% laparoscopic sleeve gastrectomy. The median time from breast cancer treatment to bariatric surgery was 3 years. The procedures were well tolerated. One female developed an abdominal wall hematoma. The average weight loss after 1 year and 2 years was 28.1% and 28.2%, respectively. There was a single breast cancer recurrence with a median follow-up of 11.7 years after breast cancer diagnosis and 5.3 years after bariatric surgery.

Conclusions
Bariatric surgery after breast cancer treatment is feasible and well tolerated. Prospective trials evaluating bariatric surgery in obese breast cancer survivors should be considered.

Full text

BRIEF COMMUNICATION
The Impact of Bariatric Surgery on Breast Cancer Recurrence: Case
Series and Review of Literature
Shijia Zhang
1
&Sayeed Ikramuddin
2
&Heather C. Beckwith
1
&Adam C. Sheka
2
&Keith M. Wirth
2
&Anne H. Blaes
1
#The Author(s) 2019
Abstract
Background Excess body weight has been associated with worsening breast cancer survival. While bariatric surgery has been
associated with less incident of breast cancer, the role that bariatric surgery plays after breast cancer diagnosis in terms of both
feasibility and in preventing breast cancer recurrence is unclear.
Methods We report the outcomes of 13 individuals who underwent bariatric surgery after definitive breast cancer treatment at a
single institution.
Results Thirteen females diagnosed with breast cancer (69.2% stage I, 23.1% stage II) at a median age of 42 years received
bariatric surgery between 2001 and 2017. The median age of bariatric surgery was 52 years. Of the 13 patients, 46.2% underwent
laparoscopic Roux-en-Y gastric bypass and 38.5% laparoscopic sleeve gastrectomy. The median time from breast cancer
treatment to bariatric surgery was 3 years. The procedures were well tolerated. One female developed an abdominal wall
hematoma. The average weight loss after 1 year and 2 years was 28.1% and 28.2%, respectively. There was a single breast
cancer recurrence with a median follow-up of 11.7 years after breast cancer diagnosis and 5.3 years after bariatric surgery.
Conclusions Bariatric surgery after breast cancer treatment is feasible and well tolerated. Prospective trials evaluating bariatric
surgery in obese breast cancer survivors should be considered.
Keywords Bariatric surgery .Weight loss .Breast cancer .Recurrence
Introduction
It is estimated that overweight and obesity could account for
14% of all deaths from cancer in males and 20% of those in
females in the USA [1]. For those with a body mass index
(BMI) between 27.5–29.9 kg/m
2
, the risk of cancer increases
by 12%, while those with a BMI over 40 kg/m
2
have a 70%
increased risk of cancer compared to those with a normal BMI
[2]. On the contrary, dramatic weight loss from bariatric sur-
gery is associated with reduced cancer mortality by approxi-
mately 40% [3]. This suggests that promoting healthy weight
change in adults can have important health benefits and out-
comes from a cancer perspective.
Our interest is to look at the impact of weight loss on breast
cancer survivors. A recent meta-analysis of 82 studies that
included 213,075 women with breast cancer demonstrated
that for each 5 kg/m
2
increment in BMI, there was a 14 to
29% increased risk of breast cancer–specific mortality and an
8 to 17% increased risk of overall mortality [4]. Multiple trials
have been initiated to look at the impact of lifestyle interven-
tion and dietary modification to produce weight loss in
*Anne H. Blaes
blaes004@umn.edu
Shijia Zhang
shijia@umn.edu
Sayeed Ikramuddin
ikram001@umn.edu
Heather C. Beckwith
einho003@umn.edu
Adam C. Sheka
sheka015@umn.edu
Keith M. Wirth
wirth129@umn.edu
1
Division of Hematology, Oncology and Transplantation, Department
of Medicine, University of Minnesota, 420 Delaware Street, SE,
MMC 480, Minneapolis, MN 55455, USA
2
Department of Surgery, University of Minnesota, Minneapolis, MN,
USA
Obesity Surgery
https://doi.org/10.1007/s11695-019-04099-6

Table 1. Characteristics of patients in our cohort
No. Age at
BC dx
BMI at
BC dx
Stage ER
+
PR
+
HER2
+
BC surgery CT CT regimen RT ET Age
at
BS
Yrs from
BC dx to
BS
BMI
at BS
Type of BS Post-op
complications
from BS
%wt
loss in
1yr
%wt
loss in
2yrs
BC
recurrence
1 50 32.6 IA Y N N Right
lumpecto-
my
N–Y Y 56 6.0 37.1 Lap sleeve
gastrectomy
None 23.5 20.2 N
2 30 52.6 IIA N N N Bilateral
mastecto-
mies
Y Doxorubicin +
cyclophosphamide
then paclitaxel
N N 33 3.0 52.3 Lap adjustable
gastric band
None 18.7 18.7 N
3 47 37.8 IA Y Y N Left
lumpecto-
my
Y Doxorubicin +
cyclophosphamide
Y Y 52 5.5 43 Lap sleeve
gastrectomy
None 26.5 26.0 N
4 57 39.4 IA Y Y N Bilateral
mastecto-
mies
N–N Y 59 2.7 38.9 Lap
Roux-en-Y
gastric by-
pass
Abdominal
wall
hematoma
14.7 10.8 N
5 35 NA IIAYYN Left
mastecto-
my
Y Cyclophosphamide +
methotrexate
+5-fluorouracil
N Y 43 7.5 40.2 Lap
Roux-en-Y
gastric by-
pass
None 31.6 36.8 Y
6 50 31.0 IA Y Y N Bilateral
mastecto-
mies
Y Cyclophosphamide +
paclitaxel
N Y 52 2.3 36.4 Lap sleeve
gastrectomy
None 40.1 37.9 N
7 36 36.9 IA Y Y Y Right
lumpecto-
my
Y Doxorubicin +
cyclophosphamide
Y Y 45 9.2 39.3 Lap sleeve
gastrectomy
None 21.1 19.8 N
8 42 35.0 IIA Y Y N Left
lumpecto-
my
Y Paclitaxel then
doxorubicin +
cyclophosphamide
Y Y 43 1.3 36.6 Lap sleeve
gastrectomy
None 35.8 24.3 N
9 42 44.0 IA Y Y N Bilateral
mastecto-
mies
N–N Y 43 1.1 42.4 Lap
Roux-en-Y
gastric by-
pass
None 33.5 46.7 N
10 41 44.3 IA Y Y N Bilateral
mastecto-
mies
Y Cyclophosphamide +
methotrexate
+5-fluorouracil
N Y 44 2.2 46.9 Lap
Roux-en-Y
gastric by-
pass
None 35.0 43.5 N
11 53 43.7 IA Y Y N Right
lumpecto-
my
N–Y Y 56 2.4 43.8 Lap
Roux-en-Y
gastric by-
pass
None 29.2 28.8 N
12 42 NA NA NA NA NA Left
lumpecto-
my
Y NA Y NA 55 13.3 38.2 Lap duodenal
switch
None 38.0 38.7 N
13 49 NA IA N N N Y NA N N 63 14.2 33.8 Lap
Roux-en-Y
None 17.5 14.2 N
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patients with a history of breast cancer. The results of these
trials have been disappointing due to poor compliance with
the proposed intervention producing only modest weight loss
and questionable results in terms of local recurrence improve-
ment. Bariatric surgery has been shown to be the most effec-
tive tool to achieve and maintain long-term weight loss. In a
large multisite cohort study, the risk of postmenopausal breast
cancer was significantly lower (hazard ratio [HR] 0.58, 95%
confidence interval [CI] 0.44–0.77, P< 0.001) among patients
who had undergone bariatric surgery compared with matched
nonsurgical controls [5]. While bariatric surgery can improve
obesity-related health problems, such as type 2 diabetes, hy-
pertension, and sleep apnea, the impact on recurrence of breast
cancer is unclear. The aim of this study was to examine the
safety of bariatric surgery after breast cancer treatment on
breast cancer recurrence. Here, we report the outcomes of 13
patients, who had bariatric surgery after definitive breast can-
cer therapy.
Methods
Following approval from the Institutional Review Board of
our institution, a computerized search from the electronic
medical records of the University of Minnesota and
Fairview Health Systems was performed for patients who
have had a diagnosis of breast cancer and underwent bariatric
surgery from 2001 to 2017. Medical records of patients who
had definitive breast cancer treatment prior to bariatric surgery
were reviewed for data collection. Descriptive statistics were
used to describe the features of the data.
Case Series
Patients included in this analysis had to meet the following
two criteria: (1) had bariatric surgery (Roux-en-Y gastric by-
pass, sleeve gastrectomy, adjustable banding, or duodenal
switch) between 2001 and 2017, and (2) had definitive treat-
ment of breast cancer prior to bariatric surgery (Table 1). A
total of 13 patients met the study criteria. All were female. The
median age of initial breast cancer diagnosis was 42 (range
30–57) years. At the time of breast cancer diagnosis, 2
(15.4%) patients had BMI in the range of 30–34.9 kg/m
2
,4
(30.8%) in the range of 35–39.9 kg/m
2
, 4 (30.8%) in range of
40 kg/m
2
and above, and 3 (23.1%) with unknown BMI. At
least 10 (76.9%) of these patients were obese (BMI ≥30 kg/
m
2
) when they were diagnosed with breast cancer. Nine
(69.2%) patients had stage I breast cancer and 3 (23.1%) had
stage II disease. The breast cancer staging of 1 (7.7%) patient
was unknown. One (7.7%) patient had a tumor that was hor-
mone receptor (HR)–positive and human epidermal growth
factor receptor 2 (HER2)–positive, 9 (69.2%) HR-positive
Tab l e 1. (continued)
No. Age at
BC dx
BMI at
BC dx
Stage ER
+
PR
+
HER2
+
BC surgery CT CT regimen RT ET Age
at
BS
Yrs from
BC dx to
BS
BMI
at BS
Type of BS Post-op
complications
from BS
%wt
loss in
1yr
%wt
loss in
2yrs
BC
recurrence
Bilateral
mastecto-
mies
gastric by-
pass
BC, breast cancer; BMI, body mass index; BS, bariatric surgery; CT, chemotherapy; dx, diagnosis; ET, endocrine therapy; lap, laparoscopic; NA, not available; RT, radiation therapy; wt, weight; yr,year
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and HER2-negative, 2 (15.4%) triple negative, and 1 (7.7%)
with unknown HR and HER2 status. All patients had surgery
for breast cancer: 6 (46.2%) patients underwent lumpectomy,
1 (7.7%) unilateral mastectomy, and 6 (46.2%) bilateral mas-
tectomies. Six (46.2%) patients had radiation therapy, and 9
(69.2%) patients received adjuvant chemotherapy. Ten
(76.9%) patients were treated with adjuvant endocrine
therapy.
The median age at bariatric surgery was 52 (range 33–63)
years. The median time from breast cancer diagnosis to bariatric
surgery was 3 (range 1.1–14.2) years. At the time of bariatric
surgery, 1 (7.7%) patient had BMI in the range of 30–34.9 kg/
m
2
, 6 (46.2%) in the range of 35–39.9 kg/m
2
, and 6 (46.2%) in
the range of 40 kg/m
2
and above. For those with available BMI
at breast cancer diagnosis, 7 out of 10 (70%) gained weight
between the time of breast cancer diagnosis and the time of
bariatric surgery. Six (46.2%) patients underwent laparoscopic
Roux-en-Y gastric bypass, 5 (38.5%) laparoscopic sleeve gas-
trectomy, 1 (7.7%) laparoscopic adjustable gastric band, and 1
(7.7%) laparoscopic duodenal switch. These procedures were
generally well tolerated by the patients. In the postoperative
period, only 1 (7.7%) patient developed abdominal wall hema-
toma in the camera trocar site resulting in a large hemoglobin
drop that required red blood cell transfusions. For most patients,
the maximal weight loss occurred within 2 years of post-
bariatric surgery (Table 2). The average weight loss after 1 year
and 2 years was 28.1% (range 17.5–40.1%) and 28.2% (range
10.8–46.7%), respectively. Furthermore, most patients main-
tained durable weight loss (Fig. 1).
There was a single breast cancer recurrence with a median
follow-up of 11.7 (range 3.9–20.6) years after breast cancer
diagnosis and 5.3 (range 2.0–9.8) years after bariatric surgery.
This patient was diagnosed with stage IIA (T2N0M0), estro-
gen receptor (ER)-positive, progesterone receptor (PR)-posi-
tive, and HER-2-negative breast cancer at age 35. She was
found to be a carrier of BRCA2 mutation. She underwent left
mastectomy followed by chemotherapy (cyclophosphamide,
methotrexate, 5-fluorouracil). She was started on tamoxifen
and then switched to exemestane after she had total abdominal
hysterectomy and bilateral salpingo-oophorectomy at age 40.
She underwent laparoscopic Roux-en-Y gastric bypass at age
43 when her BMI was 40.2 kg/m
2
. About 4 weeks after her
bariatric surgery, she was found to have local recurrence of
breast cancer and then metastatic disease. She has received
multiple lines of therapy and has been doing well.
Discussion
As the worldwide obesity epidemic spreads, we are fac-
ing more and more challenges from diabetes, cardiovas-
cular diseases, cancers, and other health conditions re-
lated to obesity. Not only is the likelihood of develop-
ment of breast cancer linked to obesity; but equally as
concerning is the higher rate of reoccurrence following
definitive therapy for breast cancer. A meta-analysis of
43 studies showed that women who were obese at
breast cancer diagnosis had an approximately 33%
higher risk of mortality compared with normal-weight
women [6]. Attempts have been made to conduct pro-
spective interventional studies to look at the impact of
weight loss on overweight breast cancer survivors. The
Lifestyle Intervention in Adjuvant Treatment of Early
Table 2. Descriptive statistics of our cohort
Characteristic Overall (N=13)
Age, median (range)
At breast cancer diagnosis 42 (30–57)
At bariatric surgery 52 (33–63)
Years from BC dx to BS, median (range) 3.0 (1.1–14.2)
BMI at breast cancer diagnosis, N(%)
30–34.9 2 (15.4)
35–39.9 4 (30.8)
40 and above 4 (30.8)
Missing/NA 3 (23.1)
BMI at bariatric surgery, N(%)
30–34.9 1 (7.7)
35–39.9 6 (46.2)
40 and above 6 (46.2)
Type of bariatric surgery, N(%)
Laparoscopic Roux-en-Y gastric bypass 6 (46.2)
Laparoscopic sleeve gastrectomy 5 (38.5)
Laparoscopic adjustable gastric band 1 (7.7)
Laparoscopic duodenal switch 1 (7.7)
Post-op complication, N(%)
None 12 (92.3)
Abdominal wall hematoma 1 (7.7)
Breast cancer stage at diagnosis, N(%)
I9(69.2)
II 3 (23.1)
Missing/NA 1 (7.7)
Hormonal receptor (HR)/HER-2 status, N(%)
HR (+), HER-2 (+) 1 (7.7)
HR (+), HER-2 (−)9(69.2)
HR (−), HER-2 (−)2(15.4)
Missing/NA 1 (7.7)
Breast cancer surgery type, N(%)
Lumpectomy 6 (46.2)
Unilateral mastectomy 1 (7.7)
Bilateral mastectomies 6 (46.2)
Treated with adjuvant chemotherapy, N(%)
Yes 9 (6 9 .2 )
No 4 (30.8)
Treated with radiation therapy, N(%)
Yes 6 (4 6 .2 )
No 7 (53.8)
Treated with endocrine therapy, N(%)
Yes 10 (76.9)
No 2 (15.4)
Missing/NA 1 (7.7)
Recurrence of breast cancer, N(%)
Yes 1 (7 . 7)
No 12 (92.3)
BC, breast cancer; BMI, body mass index; BS, bariatric surgery; dx,di-
agnosis; NA, not available
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Breast Cancer (LISA) trial randomized overweight
breast cancer survivors receiving adjuvant letrozole to
mail-based delivery of general health information ±
telephone-based lifestyle interventions over a period of
24 months. The primary endpoint was disease-free sur-
vival. Unfortunately, the enrollment was discontinued
early at 338 of 2,150 planned participants because of
loss of funding. The average weight loss in the lifestyle
interventions arm was 5.5 vs 0.7% in the control arm
after 1 year, and 3.6% vs 0.4% after 2 years. The im-
pact of this modest weight loss on breast cancer recur-
rence and mortality remains unknown [7].
Bariatric surgery is the most robust and durable therapy
for obesity and its related complications. As shown in the
LISA study, the amount of weight loss mediated by life-
style intervention is usually modest (3.6% after 2 years).
On the contrary, in our cohort of breast cancer survivors,
bariatric surgery induced significantly greater and durable
weight loss (28.2% after 2 years) in most patients. In the
Diabetes Surgery Study Randomized Clinical Trial, pa-
tients in the Roux-en-Y gastric bypass group (N= 60) lost
26.1% vs 7.9% of their initial body weight at 1 year com-
pared with the lifestyle-medical management group (N=
60). The weight loss effect persisted at 5 years: 21.8% in
the Roux-en-Y gastric bypass group vs 9.6% in the
lifestyle-medical management group in an intent-to-treat
analysis (15% of the lifestyle intervention patients actual-
ly ended up getting bariatric surgery) [8].
Analysis of the International Breast Cancer Study
Group clinical trials I–V with 4105 eligible participants
showed that the breast cancer-free rate was around 43%
for patients with ER-positive disease and 46% for those
with ER-negative disease 12 years from random assign-
ment (estimated from the breast cancer-free interval
curves), indicating high breast cancer recurrence rate [9].
In our cohort, the disease recurrence rate was 7.7% (1 out
of 13 patients) with a median follow-up of 11.7 years. It is
noteworthy that this patient was found to have breast can-
cer recurrence only 4 weeks after her Roux-en-Y gastric
bypass surgery. Therefore, it was likely too soon to evalu-
ate the impact of bariatric surgery. Also, she carries a
BRCA2 mutation and only had unilateral mastectomy,
making her at high risk for recurrent or new breast cancer.
Bariatric surgery appears to be relatively safe in patients
who had definitive breast cancer treatment—only 1 (7.7%)
patient in our cohort had bleeding in the abdominal wall in
the postoperative period. Given the small sample size, it
would not be feasible to compare the postoperative complica-
tion rate with other large studies. In a study of 268,898 meta-
bolic and bariatric surgeries performed between 2007 and
2010, the 30-day serious complication rate was 1.25% for
gastric bypass, 0.96% for sleeve gastrectomy, and 0.25% for
gastric banding. The authors did not define “serious compli-
cation”in their abstract, and it is unclear if abdominal hema-
toma would qualify for “serious complication”[10].
This study is limited by small sample size, retrospective
analysis, and no patients with stage III breast cancer at
diagnosis. Although it appears relatively safe to have bar-
iatric surgery for breast cancer survivors and most of these
patients seem to have a good outcome from a breast cancer
perspective based on our study, larger studies are required
to confirm these results. Recently, we conducted a retro-
spective cohort study of breast cancer patients undergoing
bariatric surgery 2004–2017 using de-identified data from
a large U.S. commercial insurance database (OptumLabs®
Data Warehouse). The relative risk of breast cancer events
for patients who underwent bariatric surgery was 45% low-
er than the non-surgical group [11]. With these results,
proposing bariatric surgery for obese breast cancer survi-
vors in an effort not only to reduce comorbidities such as
diabetes and hypertension but also to help prevent breast
cancer recurrence should be considered [12].
20
25
30
35
40
45
50
55
60
0 yr 1 yr 2 yr 3 yr 4 yr 5 yr 6 yr 7 yr 8 yr 9 yr 10 yr
BMI (kg/m2)
Years aer bariatric surgery
Pt 1
Pt 2
Pt 3
Pt 4
Pt 5
Pt 6
Pt 7
Pt 8
Pt 9
Pt 10
Pt 11
Pt 12
Pt 13
Fig. 1 Body mass index (BMI) at
the time of bariatric surgery and
yearly after bariatric surgery
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Conclusion
In obese breast cancer survivors, weight management strate-
gies should be utilized to prevent recurrence. Our results sug-
gest that bariatric surgery is well-tolerated in breast cancer
patients who have undergone definitive treatment for their
malignancy. As bariatric surgery is significantly more effec-
tive in producing long-term weight loss than lifestyle manage-
ment, physicians should discuss this option with obese breast
cancer patients and refer appropriate patients to a bariatric
surgeon as part of ongoing preventative therapy. A random-
ized control trial of bariatric surgery versus best medical man-
agement in obese breast cancer survivors should be
considered.
Funding University of Minnesota Innovation Research Grant.
Compliance with Ethical Standards
Conflict of Interest Authors Shijia Zhang, Heather C. Beckwith, Adam
C. Sheka, Keith M. Wirth, and Anne H. Blaes have nothing to disclose.
Author Sayeed Ikramuddin received support from Medtronic for equip-
ment for research studies, and Reshape Lifesciences for the grant support
for clinical trials.
Ethical Approval All procedures performed in studies involving human
participants were in accordance with the ethical standards of the institu-
tional and/or national research committee and with the 1964 Helsinki
declaration and its later amendments or comparable ethical standards.
Informed Consent This was a retrospective de-identified study so in-
formed consent was not obtained.
Open Access This article is distributed under the terms of the Creative
Commons Attribution 4.0 International License (http://
creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided you give appro-
priate credit to the original author(s) and the source, provide a link to the
Creative Commons license, and indicate if changes were made.
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