Keywords breast reconstruction - implant - capsular contracture
Introduction
Breast cancer is one of the most common malignancies in the female population,[1 ] and treatment regarding breast cancers involves mastectomy and immediate reconstruction
using implants or autologous tissue. Two-stage reconstruction using tissue expander
placement followed by implant insertion was once considered the most commonly used
method in breast reconstruction using implants.[2 ] However, with the advancement in skin flap viability during mastectomy and improvement
in skin- and nipple-sparing techniques in mastectomy,[3 ] reconstruction techniques have evolved from two-step reconstruction to the direct-to-implant
(DTI) technique, which is a one-step reconstruction, involving immediate insertion
of a breast implant after mastectomy.[4 ]
Over the years, breast reconstruction methods have evolved into more efficient and
less invasive techniques. The prepectoral technique has become a popular alternative
to traditional subpectoral approaches in implant-based breast reconstruction. Key
advantages include a reduced risk of breast animation deformities and less discomfort
from avoiding pectoralis major muscle elevation. Also, there are no significant differences
in postoperative complications, such as infection, skin flap necrosis, or capsular
contracture, between prepectoral and subpectoral methods.[4 ]
[5 ]
[6 ]
[7 ]
[8 ] Consequently, the prepectoral DTI technique is gaining traction as a reliable option
in breast reconstruction.
Capsular contracture is a common complication in implant-based breast reconstruction.
Various studies have investigated potential causes, including implant type, placement
plane, use of acellular dermal matrix (ADM), history of chemotherapy and radiotherapy,
and the impact of postoperative infections or biofilms.[7 ]
[8 ]
[9 ]
[10 ]
[11 ]
[12 ] Despite this, the exact mechanism and contributing factors remain unclear, as findings
are often inconsistent due to small sample sizes, differing reconstruction methods,
and the lack of matched control groups across studies. Our study aimed to investigate
the causes and surgical outcomes of capsular contracture in patients undergoing prepectoral
DTI. We focused specifically on prepectoral DTI interventions and the factors influencing
capsular contracture. Additionally, we analyzed the surgical outcomes of patients
who developed capsular contractures and required further procedures. Through this
analysis, we hope to provide guidelines for predicting, treating, and preventing capsular
contracture in prepectoral DTI patients, ultimately leading to more personalized and
improved reconstructive surgery.
Methods
Study Design and Population
Patients who underwent prepectoral DTI (robot-assisted DTI included) between August
2019 and July 2022 at XXX Hospital of the XXX University College of Medicine were
enrolled in the study. Our study design was approved by the Hospital Institutional
Review Board (IRB approval number 2023-2301-001). To create a homogenous patient population,
patients diagnosed with metastatic disease and with less than a 6-month follow-up
period were excluded from the study. We analyzed each patient's clinicopathological
features, including demographics, TNM (tumor, nodes, and metastases) stage, intraoperative
findings (mastectomy type), neoadjuvant and adjuvant therapies, and postoperative
complications. Pre- and postoperative clinical photographs were acquired and reviewed.
The capsular contracture in this study referred to the degree of grades III (a breast
firm to touch that appears distorted) and IV (a breast hard and painful to touch that
appears distorted) outcomes according to the Baker–Spear classification system.[13 ] Surgical infection was defined according to the Centers for Disease Control and
Prevention (CDC) surgical site infection definition criteria, which involves infection
occurring within 30 or 90 days after the operative procedure involving deep soft tissues
of the incision. Hematoma was defined as an incidence of intervention due to its cause,
such as negative drain insertion or surgical intervention. Therefore, we examined
the association between capsular contracture and these factors. Furthermore, a surgical
intervention was performed for patients who experienced discomfort in daily life due
to capsular contracture and wished for surgical correction, the decision to proceed
with surgery was based on the patient's subjective discomfort rather than the Baker–Spear
classification criteria. The surgical results of these groups were analyzed. Among
the patients who underwent surgical treatment, informed consents were obtained from
participants who agreed to provide pre- and postoperative photographs ([Figs. 1 ]
[2 ]
[3 ]).
Fig. 1 A case of a 51-year-old female, with a history of bilateral breast augmentation,
skin-sparing mastectomy, implant change, and radiotherapy. Partial capsulectomy was
performed, mainly focusing on the inframammary fold where capsular contracture was
noticeable in this patient. Figures during the procedure; before (left) and after
partial capsulectomy (right).
Fig. 2 A case of a 40-year-old female, with a history of bilateral prepectoral direct-to-implant
(DTI). The figure shows breasts previous to the first implant insertion (left), 31
months after the first implant insertion with noticeable capsular contracture on left
side of the breast (middle), and at the 8-month follow-up after capsulectomy was performed
(right).
Fig. 3 A case of a 41-year-old female, with a history of bilateral prepectoral direct-to-implant
(DTI) and radiotherapy. The figure shows breasts previous to the first implant insertion
(left), 15 months after the first implant insertion with noticeable capsular contracture
on right side of the breast (middle), and the 2-year follow-up after implant change
and capsulectomy was performed (right).
Surgical Techniques
Following mastectomy, a sizer implant was placed to assess the appropriate volume
of the breast implant. Indocyanine green was injected to assess the viability of the
mastectomy skin flap. After the surgeon determined the volume of the breast implant,
it was completely covered with human ADM (MegaDerm graft; L&C Bio Corp., Seoul, Korea)
and fixed to the pectoralis major muscle. Complete coverage with ADM was achieved
in all patients and a smooth cohesive mammary gel implant was used. The ADM-covered
implant was positioned in position by the surgeon, and after placing it in the right
position, it was fixed over the pectoralis muscle by fixing the ADM onto the pectoralis
muscle with sutures. Sutures were placed at four points on the upper part of the implant
to the pectoralis muscle, securing the implant's position. The suture was done from
the medial to the lateral side.
Among patients with capsular contracture, during postoperative follow-up, only those
patients who were willing to undergo surgery due to its discomfort or appearance underwent
surgical correction. An incision was made along the previous incision to remove the
implant. The condition of the capsule was examined by the operator and capsulectomy
was performed on relatively rigid and pathologically visible capsules as could be
seen in [Fig. 1 ]. After partial capsulectomy on relatively visible capsules, resolvement of capsular
contracture was noticeable by the operator as the pocket returned to original shape
and place during the operation. If the skin flap was too thin, ADM was grafted after
capsule removal. Once all pocket operations were completed, a new implant of the appropriate
size was reinserted and surgery was completed.
Statistical Analysis
Continuous variables are expressed as mean ± standard deviation, and nominal variables
are expressed as frequency (%). Comparative analyses were performed using the chi-square
test and Student's t -test. The significance of the differences between groups was assessed using a log-rank
test. Multivariate analysis was performed to identify risk factors for capsular contracture
using a Cox proportional hazards model. Statistical significance was set at p -values <0.05.
Results
General Characteristics of Patients
The medical records of 410 patients (a total of 512 breasts) were retrospectively
reviewed. To create a homogenous patient population, patients diagnosed with metastatic
disease (n = 3) and who were lost during the follow-up period (<6 month follow-up period) were
excluded (n = 15) from the study. Therefore, 392 patients and (472 breasts) were retrospectively
reviewed. [Table 1 ] shows the demographic and clinicopathological characteristics of the prepectoral
group. The mean follow-up period was 20.0 ± 13.9 months, and the patients had an average
age of 47.6 ± 9.4 years. The average body mass index (BMI) of the patients was 23.2 ± 3.4 kg/m2 , and the average specimen weight and implant sizes were 396.1 ± 179.0 g and 309.4 ± 100.6 mL,
respectively.
Table 1
Clinical characteristics, complications and adjuvant therapy concerning cancer
Variable
Mean ± SD
Age, years
47.6 ± 9.4
BMI, kg/m2
23.2 ± 3.4
Specimen weight, g
396.1 ± 179.0
Implant size, mL
309.4 ± 100.6
Mastectomy type
Nipple-sparing mastectomy
361 (76.5%)
Skin-sparing mastectomy
82 (17.4%)
Total mastectomy
29 (6.1%)
Stage
0
111 (23.5%)
IA
152 (32.2%)
IB
2 (0.4%)
IIA
92 (19.5%)
IIB
38 (8.1%)
IIIA
21 (4.4%)
IIIC
4 (0.8%)
Preventive
52 (11.0%)
Complications
Infection
11 (3.0%)
Capsular contracture
47 (9.9%)
Seroma
24 (5.1%)
Hematoma
28 (5.9%)
Implant rupture
13 (3.6%)
Exposure
12 (2.5%)
Rippling
49 (13.6%)
Malposition
23 (4.8%)
Skin flap necrosis
27 (5.7%)
Adjuvant therapy
Neoadjuvant CTx
65 (13.7%)
Post CTx
57 (12.1%)
Pre RTx
3 (0.6%)
Post RTx
78 (16.5%)
Anti-EST Tx.
146 (30.9%)
Target Tx.
21 (4.4%)
Abbreviations: anti-EST, anti-estrogen therapy; BMI, body mass index; CTx, chemotherapy;
RTx, radiotherapy; SD, standard deviation.
All data are expressed as mean ± sd or N (%).
Nipple-sparing mastectomy was performed in 361 breasts (76.5%), skin-sparing mastectomy
in 82 (17.4%), and total mastectomy in 29 (6.1%). Regarding postoperative complications,
47 breasts (9.9%) had capsular contractures, 24 (5.1%) showed signs of postoperative
seroma, and 11 patients (3.0%) had surgical site infections. Rippling was observed
in 54 breasts (11.4%). Approximately 30% of the patients underwent anti-hormonal therapy;
65 breasts (13.7%) underwent neoadjuvant chemotherapy, and 57 (12.1%) received postoperative
chemotherapy. Postoperative radiation therapy was administered to 78 breasts (16.5%;
[Table 1 ]).
Determining Correlating Factors of Capsular Contracture
A multivariate analysis was performed and adjusted for the following confounding factors:
age, BMI, tumor stage, mastectomy type, complications, and adjuvant therapies. The
analysis showed that age (OR = 0.95, [95% CI: 0.91–0.98], p = 0.002), incidence of seroma (OR = 3.57, [95% CI: 1.46–8.62], p = 0.004), incidence of rippling (OR = 0.34, [95% CI: 0.08–0.71], p = 0.011), and postoperative radiation therapy (OR = 5.29, [95% CI: 1.63–18.28], p = 0.007) were independent correlating factors of capsular contracture ([Table 2 ]). Higher age and incidence of rippling were independent correlating factors for
a lower risk of capsular contracture, whereas the incidence of seroma and postoperative
radiotherapy were independent factors leading to capsular contracture. However, due
to the association between thicker capsule presence and less pronounced rippling,
it is challenging to assert that rippling incidence affects capsular contracture,
despite what the analysis indicates.
Table 2
Determining risk factors of capsular contracture
Variable
OR
2.50%
97.50%
p -Value
Age, years
0.95
0.91
0.98
0.002
BMI, kg/m2
1.11
1.00
1.18
0.132
Stage
0
(Ref)
I
1.31
0.44
3.72
0.458
II
10.49
4.40
26.99
0.147
III
31.11
7.63
142.00
0.214
Preventive
3.32
1.24
9.11
0.018
Mastectomy type
Nipple-sparing mastectomy
(Ref)
Skin-sparing mastectomy
0.44
0.19
0.98
0.052
Total mastectomy
1.09
0.34
3.24
0.776
Complications
Infection
2.59
0.71
8.86
0.134
Seroma
3.57
1.46
8.62
0.004
Hematoma
0.10
0.05
0.23
0.141
Rupture
2.16
0.68
6.76
0.185
Rippling
0.34
0.08
0.71
0.011
Malposition
3.62
0.15
46.86
0.330
Necrosis
0.32
0.07
1.21
0.123
Infection
2.59
0.71
8.86
0.144
Adjuvant therapy
Neoadjuvant CTx
0.19
0.05
0.60
0.137
Post-CTx
0.22
0.07
0.60
0.155
Post-RTx
5.29
1.63
18.28
0.007
Anti-EST
0.77
0.36
1.56
0.444
Target
0.45
0.05
1.70
0.233
Abbreviations: Anti-EST; anti-estrogen therapy; BMI, body mass index; CTx; chemotherapy;
RTx, radiotherapy.
Management of Capsular Contracture
Among the 47 breasts diagnosed with capsular contracture, a partial capsulectomy was
performed in 18 breasts, and contractures resolved in 88.9% of the cases during an
average follow-up of 14.4 months ([Figs. 2 ] and [3 ]). Relatively visible and rigid capsules on the lateral side of the breast were observed
in 16.7% of the cases, whereas 77.8% of cases showed rigid, visible capsules mainly
on the lower side. One case (5.6%) showed rigid, visible capsules on both the lateral
and lower sides of the breast compared with other regions. Most of the patients did
not go through surgical procedures and were treated with tranilast to resolve capsular
contracture. Among patients who underwent surgical procedures, recurrence of capsular
contracture was observed in two cases. In these two cases, an improvement in the degree
of capsular contracture was observed: grade IV according to the Baker–Spear classification
system before surgery and grade III in both cases postoperatively.
Discussion
Our study distinguishes from other studies in that while most studies focus on resolving
capsular contracture in breast augmentation, we focused on its treatment in breast
reconstruction. Capsular contracture in breast reconstruction negatively impacts a
patient's quality of life in that it causes physical discomfort or pain, as the capsule
tightens around the implant. This can lead to a distorted breast shape, resulting
in aesthetic dissatisfaction. Additionally, the tightness and discomfort can restrict
movement, making daily activities more difficult. The need for corrective surgeries
also adds emotional and financial stress, further diminishing overall well-being.
Therefore, understanding the mechanisms behind capsular contracture is crucial not
only for improving patients' overall satisfaction with breast reconstruction but also
for ensuring the success of the reconstruction itself.
When an implant is inserted into the body, it is recognized as a foreign substance,
causing an inflammatory response and creating a fibrous capsule that encloses the
implant. The capsule created this way usually has a benign character, but in some
cases, it causes additional inflammatory reactions, compressing the implant, and causing
pain and deformation of the breast shape.
Factors associated with the etiology of capsular contracture include a history of
postoperative radiation and the presence of chronic inflammation, such as chronic
seroma and subclinical bacterial infection. Although there is a consensus among surgeons
on the inflammatory nature of capsular fibrosis, the diverse array of inciting events
initiating the inflammatory cascade renders it challenging to predict why some patients
develop capsular contracture while others do not.[14 ] Seroma, which is a potent medium for bacterial proliferation and known to harbor
a notably high concentration of proinflammatory cytokines, poses an elevated risk
of capsular contracture. This heightened risk stems from increased levels of proinflammatory
mediators within the periprosthetic capsule, which drives fibrosis. Additionally,
residual seroma fluid, rich in inflammatory mediators, may predispose to bacterial
infection and biofilm formation.[15 ]
History of radiation therapy is also known for its effect on capsular contracture
by inducing capsule contracture and fibrosis of surrounding tissues. Both prepectoral
and subpectoral breast reconstructions exhibit elevated rates of capsular contracture
with a history of radiation therapy.[16 ] Histological studies highlight heightened elastin and cellular infiltrates in native
capsules with a radiation therapy history, emphasizing its involvement in capsular
contracture development.[17 ]
Although age is not known to be a factor related to capsular contracture, the significant
difference observed in this study may be attributed to the high proportion of younger
patients among Korean breast cancer patients. It is generally known that collagen
synthesis decreases with age.[18 ]
[19 ] It can be inferred that older patients have relatively reduced collagen synthesis
activity, which in turn might influenced decreased incidence of capsular contracture.
Through multivariate analysis, which was adjusted for many confounders, our study
showed that the presence of seroma and a history of radiation therapy was an independent
correlating factor of capsular contracture. This finding supports the idea that the
presence of a seroma, rich in inflammatory mediators, is an independent correlating
factor of capsular contracture. When we examined our cases of partial capsulectomy
for capsular contracture, capsular contracture was observed mainly in the dependent
portion of the body, the location where the seroma was likely situated, further supporting
this idea.
While capsulectomy is commonly recommended for managing capsular contracture, a recent
meta-analysis found no significant difference in recurrence rates between capsulectomy
and capsulotomy.[20 ] Also, autologous reconstruction is often considered the definitive solution due
to its elimination of long-term risks and more natural results, our findings suggest
that partial capsulectomy could be a viable alternative.[21 ] In our study, partial capsulectomy in 18 cases achieved a resolution rate of approximately
90%, suggesting this approach may offer an effective solution for capsular contracture
in breast reconstruction.
Regarding the limitations of our study, this was a single-center, retrospective study
with a limited number of patients who underwent partial capsulectomy, and the results
would have been more accurate and powerful with a larger sample size. Therefore, further
studies with larger sample sizes are required to validate and generalize our findings.
Also, due to the retrospective nature of this study, the evaluation of Baker grade
was conducted by the operator during outpatient visits. This evaluation may hinder
the objectivity of the study in that when assessing capsular contracture, the evaluation
can vary among observers. Therefore, the frequency or stage of capsular contracture
may differ based on who is conducting the assessment.[22 ] The absence of alternative objective evaluation standards has left us with no choice
but to use such methods as most studies on capsular contracture do so.
Conclusion
Our multivariate analysis demonstrated that age, seroma, rippling, and radiotherapy
were independent correlating factors for capsular contracture in prepectoral DTI.
Partial capsulectomy, a relatively simple and less invasive option, could be considered
as an alternative to traditional capsulectomy or autologous tissue reconstruction
for managing capsular contract. Through our study, we hope to pave the way for larger,
more objective research on this topic, ultimately contributing to the establishment
of guidelines for the surgical management of capsular contracture in the future.
