Keywords
head and neck cancer - carotid artery stent - carotid blowout syndrome - pectoralis
major myocutaneous flap - complication
Introduction
Head and neck cancer (HNC) is a major cause of morbidity and mortality in the United
States with an estimated 61,000 new cases and 13,000 deaths annually.[1] Treatment options for HNC have evolved in recent decades, allowing for longer survival:
the 5-year survival rate for oral cavity and pharyngeal cancers has increased from
52.7% in 1975 to 66.2% in 2008.[2] As survival from these cancers continues to improve, an increase in associated treatment-
and disease-related complications is expected.
Carotid blowout syndrome (CBS), that is, rupture of the extracranial carotid arteries
or their major branches, is one of the most feared complications, with a reported
incidence of 3 to 4% in patients with HNC.[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10] CBS is associated with 60% morbidity and 40% mortality.[3]
[4]
[6]
[7]
[10]
[11]
[12]
[13] In patients with advanced HNC, risk factors for the development of CBS are radiation,
stripping of the carotid artery during surgery, skin breakdown, and development of
mucocutaneous fistula.[14] CBS has historically been managed with surgical carotid artery ligation. However,
more recently developed endovascular techniques, including selective embolization
and reconstruction with covered stent grafts, have become the mainstay of treatment.[3]
[4]
[5]
[6]
[7]
[8]
[10]
[11]
[15]
Immediate complications associated with the use of covered stent grafts after CBS
have been extensively reported and include acute thromboembolism and iatrogenic dissection.
Mid- and long-term complications may involve rebleeding (13–44% incidence) and stent
thrombosis associated or not symptomatic ischemic cerebrovascular accidents.[3]
[5]
[7]
[8]
[10]
[13]
[14]
[15]
[16] Nevertheless, the literature on cutaneous exposure of CAS and its management are
scarce.[4]
[17]
In this retrospective series, we describe our experience with recurrent unresectable
HNC that underwent CAS placement for CBS treatment and complicated with cutaneous
exposure of the stent. The use and rationale behind selecting the pectoralis major
myocutaneous flaps (PMMF) for reconstruction in this particular cohort are discussed.
Methods
A single-institution retrospective analysis was performed to identify recurrent HNC
patients who underwent CAS placement for CBS and complicated with cutaneous exposure
of the stent between 2014 and 2016. Medical records were reviewed with attention to
cancer diagnosis, treatment history, pre-, intra-, and postoperative courses, anticoagulation
needs, and durability of the reconstruction. The study was approved by the Rush University
Medical Center Institutional Review Board.
Results
We identified three male patients with diagnosis of head and neck squamous cell carcinoma,
age ranged from 59 to 64 years, who presented with a right CAS exposed in a large,
ulcerative wound. Treatment history for all patients involved at least one oncological
surgery in addition to adjuvant chemotherapy and radiation.
Timing between CAS placement and cutaneous exposure ranged from 6 to 156 weeks. All
patients underwent a right PMMF to cover the exposed stent within 30 days of presentation
to our institution.
Reconstruction Technique
Initially the skin edges surrounding the wound of the exposed stent were debrided
and freshened to allow for an inset of the planned flap. If the surrounding tissue
can be cleared of gross malignancy, this was performed as in case 1 of our series.
A myocutaneous pectoralis flap was harvested in the standard fashion centered on the
pectoralis branch of the thoracoacromial artery. Sternal attachments and humerus attachments
were released to allow for appropriate rotation and inset. Innervations to the pectoralis
major muscle was transected during the harvest to allow for thinning of the flap.
The skin paddle was fashioned to be inset to the surrounding tissue and the bulk of
the pectoralis muscle overlying the stent and inset to the deeper tissue. The donor
site was closed with local flaps in all cases and given the anticoagulated states
of the patient's appropriate drains were used. ([Figs. 1]–[3])
Fig. 1 Preoperative photo exhibiting the severity of the defect, with visible exposed mesh
of the right carotid artery stent. This is Case 1.
Fig. 2 Intraoperative photo demonstrating exposed carotid artery stent immediately prior
to reconstruction with PMMF. PMMF, pectoralis major myocutaneous flap. This is Case
1.
Fig. 3 Intraoperative photo taken prior to reconstruction with harvested PMMF, highlighting
exposed right common carotid artery stent with visible mesh (white arrow). This is
Case 2. PMMF, pectoralis major myocutaneous flap.
Outcomes
Two of three patients attained adequate coverage of the stent for more than 30 days,
while one experienced partial flap dehiscence within 12 days requiring surgical revision
for wound debridement. Despite the flap dehiscence, the stent was still covered and
the wound was managed conservatively with dressing changes and topical ointment. Two
patients developed postoperative chest hematomas that were managed conservatively.
Two of three patients were able to undergo further palliative adjuvant treatments
within 60 days of the initial surgical procedure. Wound healing time and, most significantly,
the patient debilitating status were the reasons for adjuvant treatment delay.
Case 1 returned to work and upheld a reasonable quality of life within 3 weeks of
surgery. Palliative treatment with immunotherapy was started 6 weeks after PMMF surgery
due to problems with his port-a-cath. His follow-up in clinic was approximately 4
months after surgery showed adequate wound coverage ([Fig. 4]), and he eventually expired of regional and metastatic disease progression.
Fig. 4 Postoperative photo demonstrating well-healed reconstruction approximately 4 months
after surgery. This is Case 1.
Despite the partial flap dehiscence requiring debridement and wound care, case 3 was
able to start palliative treatment with immunotherapy 3 weeks after PMMF surgery.
He also underwent subsequent palliative systemic chemotherapy, palliative radiation
to metastatic lung lesion and ultimately died in hospice care due to regional and
metastatic disease progression 7.5 months after surgery.
The details on each case are summarized in [Table 1].
Table 1
Summary of cases with exposed CAS
|
Case no.
|
1
|
2
|
3
|
|
Age at presentation (y)/gender
|
59/male
|
64/male
|
61/male
|
|
1-degree cancer site
|
SCC of tongue
|
SCC: 1-degree site unknown
|
SCC of right tonsil
|
|
HPV status
|
Unknown
|
Unknown
|
Positive
|
|
Smoking status
|
Former smoker
|
Former smoker
|
Never smoker
|
|
Number of prior oncologic surgeries
|
2
|
1
|
2
|
|
Prior adjuvant treatments
|
Chemotherapy, radiation
|
Chemotherapy, immunotherapy, radiation
|
Chemotherapy, radiation
|
|
Prestent radiation dose
|
N/A
|
70 Gy to lesion; 60 Gy to bilateral neck
|
70 Gy to lesion; 30 Gy neck recurrence (×2)
|
|
Time from carotid stent placement to cutaneous exposure (wk)
|
16
|
6
|
152
|
|
Reconstruction method
|
PMMF
|
PMMF
|
PMMF
|
|
Excised skin margins positive for SCC?
|
No
|
Yes
|
Yes
|
|
Site of distant metastatic disease
|
Right neck
|
Right neck
|
Right neck, right lung
|
|
Postoperative anticoagulation
|
Aspirin, clopidogrel, enoxaparin (for PE)
|
Aspirin, clopidogrel
|
Aspirin, clopidogrel
|
|
Postoperative complications
|
Chest wall hematoma, cellulitis of neck with mild dehiscence
|
Mild flap dehiscence (stent remained covered)
|
Flap dehiscence, chest wall hematoma
|
|
Durable flap coverage[a]?
|
Yes
|
Yes
|
No, 12 days
|
|
Further postoperative adjuvant treatments?
|
Palliative with chemotherapy and immunotherapy
|
No
|
Palliative with chemotherapy, immunotherapy and palliative radiation to the lung
|
Abbreviations: CAS, carotid artery stents; HPV, human papillomavirus; N/A, not available;
PE, pulmonary embolism; PMMF, pectoralis major myocutaneous flap; SCC, squamous cell
carcinoma.
a Greater than 30 days of flap coverage is considered durable in this series.
Discussion
Endovascular techniques designed to treat CBS have more recently come into favor,
as they are less invasive than surgery and avoid the need to operate in a field often
complicated by prior neck dissection and/or radiation therapy.[3]
[9]
[11]
[12] Covered stent grafting is the preferred alternative in those who cannot tolerate
occlusion of the offending carotid artery such as patients with contralateral carotid
artery disease.[4]
[5]
[7]
[12]
[13]
[14]
[16]
Considering the potential catastrophic consequences of a hemispheric ischemic stroke,
we believe all attempts should be made to preserve the internal carotid artery (ICA)
and intracranial blood flow. Balloon test occlusions (BTO) may be challenging to perform
in an emergency setting of a CBS. In addition, 15% of elective BTOs may have false
negative results,[18] so ICA sacrifice should be used as a last resort to control bleeding.
In a CBS scenario, embolization or vessel sacrifice is a preferred treatment method
when dealing with hemorrhage from external carotid artery or its branches. However,
a reconstructive technique with stent is the preferred method when the bleeding source
is the common or internal carotid arteries.
The most commonly reported mid- and long-term complications related to CAS in this
patient population are rebleeding, infection, and stent thrombosis associated or not
symptomatic ischemic cerebrovascular accidents. The complication of exposed CAS is
an uncommonly reported in literature,[4]
[17] and minimal published information exists regarding the management of such cases.
As observed in our patient cohort, we believe this complication is likely associated
with extensive history for the HNC treatment (multiple surgeries, radiation therapies,
and chemotherapies), advanced disease, comorbidities, and poor nutritional status.
We will likely see an increase in treatment- and disease-related complications as
HNC survival continues to improve with better immunotherapies and chemotherapies.
Despite the widespread use of vascularized flaps to cover persistent soft tissue wounds
in which the carotid artery is exposed,[4]
[10]
[13] there are no reports on the impact of having an exposed implant in these reconstructions.
To the best of our knowledge, this is the first reported case series delineating the
use of PMMF in this patient cohort.
Warren et al[4] published an excellent review and report of three patients with carotid blowout
managed with endovascular stents and questioned the long-term safety of indwelling
stents in the setting of head and neck malignancy. Although initial results in this
article were favorable, two patients extruded their stent resulting in cerebrovascular
accident in one case and thrombosis in the second.
Simental et al[17] reported two patients with poor outcomes with CAS exposure after treatment of CBS.
The wound defect was covered with a total arm myocutaneous flap in the first case.
The patient had new bleeding within 30 days after procedure requiring sacrifice of
the common carotid artery, which resulted in an ischemic stroke and death. The second
patient presented with CAS exposure after 8 weeks of placement. The common carotid
artery had thrombosed and the patient subsequently expired to generalized inanition
from recurrent carcinoma with no further bleeding.
Although microvascular surgery in vessel-depleted necks has been described in head
and neck reconstruction, the extent of disease and severely debilitated and the anticoagulated
state of this particular patient cohort persuaded us against free-tissue transfer.
Our goal was to achieve an extremely low incidence of complete flap failure; as such,
a pedicled flap was an ideal choice. The PMMF is particularly useful in salvage procedures,
where the neck is vessel depleted, and also may allow for shorter operative times
for wound coverage that is critical in this patient cohort. Often selected for its
reliability, versatility, ease of harvest, and ability to cover large tissue defects
in the head and neck region, the PMMF is easily mobilized and far reaching with the
thoracoacromial artery as the axial vessel.[19] One distinct advantage of the short postoperative recovery period is the ability
to undergo further systemic treatments after surgery, as seen in two patients in this
series.
In the present series of salvage procedures, all patients faced posttreatment complications,
including two patients who experienced postoperative bleeding and two with mild flap
dehiscence. Patients with advanced HNC who have undergone numerous salvage treatments
suffer treatment-related complications more readily, and rates of partial PMMF necrosis
after salvage surgery tend to be higher than those undergoing primary surgery.[20] Therefore, discussion of the risks and benefits of palliative treatments is crucial.
In this case series, PMMF was used to cover exposed CAS and resulted in durable coverage
in two of three cases. All patients experienced greater than 30 days of survival (range:
73–232 days) and were able to be discharged from the hospital after flap placement,
and two of the three patients were able to undergo further palliative adjuvant therapies
within 60 days of surgery. Although uncommon, cutaneously exposed intraluminal CAS
present critical management considerations that are not yet well elucidated in the
literature.
Conclusion
Our experience suggests PMMF provide a durable, safe, and reliable option for coverage
of exposed CAS, allowing patients to pursue further therapeutic or palliative treatments.
Future comparative studies will aid in guiding the management of HNC patients with
neck wounds containing exposed endovascular carotid artery stents.
