Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_623_Библиотеки_им_академика_М_И_Перельмана
.pdf
The breast 385
https://t.me/medicina_free
• Axillary node sampling (ANS) is indicated if the
sentinel node cannot be identified, either because
of failure of the localizing injections or due to previous surgery in the axilla. A sample of a minimum
of four lymph nodes are removed for histological
analysis.
When the sampled nodes are free of tumour, no further axillary surgery is required. If there are positive
nodes following SLN biopsy or ANS, then further
treatment to the axilla might be required in the form
of axillary radiotherapy or axillary clearance.
Positive axillary nodes at
presentation
Positive axillary nodes at presentation implies the
possibility of onward nodal spread. There are two surgical options for such patients:
Axillary node clearance (ANC), removing all the
•
nodes lateral and deep to the pectoralis minor
muscle (a level I and II clearance) (see
Figure35.3).
• Targeted axillary dissection (TAD) is an evolving
approach for patients with 1–2 positive nodes at
presentation undergoing neoadjuvant chemotherapy. If there is evidence of good response to
neoadjuvant chemotherapy, then the previously
positive nodes can be removed along with the sentinel nodes. If all the nodes are now negative for
cancer cells, then no further treatment is required
for the axilla.
Complications
Complications of axillary surgery include the risk of
lymphoedema, which is increased with the greater
extent of dissection (20% after ANC vs 6% after SLN
biopsy) along with the risks of pain, numbness, shoulder stiffness and damage to the axillary nerves and
vessels (e.g. winged scapula following damage to the
long thoracic nerve).
Breast reconstruction
Breast reconstruction may be performed either at the
time of mastectomy (immediate) or as a delayed procedure. The combination of skin- or nipple- sparing
mastectomy and immediate breast reconstruction
may produce better cosmetic results. Reconstruction
does not appear to impede the ability to detect local
recurrence and is of psychological benefit.
The choice of reconstruction for a suitable individual patient will depend on several factors, including
breast size, the adequacy of skin flaps, whether radiotherapy is planned or has previously been used,
abdominal size and previous abdominal operations,
smoking status, lifestyle, comorbidities, body mass
index and the patient’s preference. Common reconstructions include the following:
1
Implant based: a breast implant containing either sili-
cone, saline or both, is used to replace the excised
breast tissue. It is placed either above (prepectoral) or
below (subpectoral) the pectoralis major muscle. It
can be done as one or two stages. The latter involves a
tissue expander to increase the skin envelope, which
is later on replaced by a permanent implant.
Common complications of implants include the
risk of rupture and infection that can result in
implant loss, as well as the risks of rotation, animation and capsular contracture that may require
a revision. A very rare entity called breast implant
associated anaplastic large cell lymphoma (BIAALCL) is also included in the consent process.
2 Autologous flaps: skin and fat with or without the
underlying muscle is used to replace the breast,
based on its own vascular pedicle. A flap may be
pedicled (swung around on its existing blood supply) or free (pedicle removed and anastomosed to
vessels in the mastectomy site). These can be one
of the following:
a
Latissimus dorsi myocutaneous flap: pedicled
flap based on the thoracodorsal artery (a continuation of the subscapular artery).
Deep inferior epigastric artery perforator
b
(DIEP) flap: the most commonly used free flap,
where an island of skin and fat from the lower
abdominal wall is used to reconstruct the
breast. It includes an abdominoplasty for flap
harvesting and microsurgery for the anastomosis of the flap to the chest wall. The amount
of harvested tissue is usually sufficient for
bilateral breast reconstruction, if indicated.
c
Transverse rectus abdominis myocutaneous
(TRAM) flap: based on the inferior epigastric
vessels, a transverse skin ellipse with underlying fat and a portion of the rectus abdominis
muscles. It can be pedicled or free. However,
due to the implications to abdominal wall
weakening this flap is now less frequently used.
Complications of autologous reconstructions
include the scarring, infection and weakening
of the donor sites, as well as site-
related
386 The breast
https://t.me/medicina_free
complications. The risk of postoperative thromboembolism is also increased with these operations.
Combination of flap and implant.
3
Systemic therapy
Adjuvant systemic therapy (after the operation)
using cytotoxic agents and/or endocrine therapy
improves survival and reduces recurrence, with greatest benefit in those women at greatest risk of relapse.
Treatments are continuously evolving and have contributed in a dramatic increase in disease- free and
cancer- specific survival over the years.
The choice of adjuvant systemic therapy is individualized and based on disease factors, patient overall
status and patient preferences. Prognostic factors that
predict relapse and risk calculators, like PREDICT,
may help to categorize this risk and select appropriate
adjuvant therapy (see earlier in this chapter on prognostic factors).
Endocrine therapy is recommended in all patients
1
with ER- positive breast cancer. Duration of treatment is debatable; usual recommendation is for at
least 5 years if tolerated, with potential extension
to 10 years for higha Tamoxifen, an oestrogen receptor antagonist
in the breast tissue, is mainly used in premenopausal women. It is commonly associated
with menopausal symptoms, such as hot
flushes.
Aromatase inhibitors (AIs), like letrozole and
b
anastrozole, block extraduction in postmenopausal women. They may
result in bone loss and joint pains due to oestrogen deficiency, which requires monitoring.
Ovarian function suppression by drug ther-
c
apy (LHRH inhibition, e.g. goserelin), or by
oophorectomy and rarely irradiation, may be
indicated for premenopausal women with
high- risk ER- positive tumours, in addition to
tamoxifen or AIs.
2 Combination chemotherapy, with anthracyclines
and taxanes is used in different schemes. Regimen
choice varies according to institution and clinicians. Due to treatment toxicity, suitable patients
for chemotherapy should be carefully assessed.
3 Monoclonal antibody therapy: directed to the
HER2 improves prognosis in HER2- positive breast
cancer. These agents are Trastuzumab (Herceptin)
with or without Pertuzumab (Perjeta).
4 Bisphosphonates: like zoledronic acid and clo-
dronate, may reduce the risk of the breast cancer
risk tumours.
ovarian oestrogen pro-
spreading to the bones and improve survival in
risk postmenopausal women.
high-
A suggested outline for adjuvant systemic therapy is
as follows.
1
Premenopausal women.
Low- risk disease: tamoxifen if ER positive.
a
b
Intermediate- risk disease and ER- positive
tumours: tamoxifen possibly with ovarian
function suppression. Chemotherapy discussion or genomic assays if indicated. AntiHER2- directed treatment, if HER2 positive.
c High- risk disease and ER- positive tumours:
tamoxifen with ovarian function suppression,
likely extended duration. Chemotherapy. AntiHER2- directed treatment, if HER2 positive.
d Low/Intermediate/high- risk disease which is
ER negative: chemotherapy.
2
Postmenopausal women.
a Low- risk disease: AIs, usually Letrozole, if ER
positive. Tamoxifen, if AIs not tolerated or
contraindicated.
Intermediate- risk disease and ER- positive
b
tumours: letrozole. Chemotherapy discussion
or genomic assays if indicated. Antidirected treatment, if HER2 positive.
c High- risk disease and ER- positive tumours:
letrozole, likely extended duration chemotherapy and bisphosphonates. Antitreatment, if HER2 positive.
Low/Intermediate/high- risk disease which is ER
d
negative: chemotherapy and bisphosphonates.
Neoadjuvant systemic therapy (before any operation) usually refers to chemotherapy with or without
anti-
HER2- directed treatment; however, the role of
neoadjuvant endocrine therapy is also expanding.
Neoadjuvant systemic therapy is indicated for:
Downstaging the disease: this can allow for less
•
extensive surgery to the breast and axilla in locally
advanced disease. This can lead to improved cosmesis and decreased risk of postoperative complications i.e. can allow breast conservation versus
mastectomy or TAD versus axillary clearance.
• Assessing the response: this can determine the
prognosis; pathologic complete response (pcr)
signifies the best prognosis It can also allow the
selection of different agents, if there is only partial
or no response to neoadjuvant treatment.
HER2 positive breast cancers have the highest pcr
rates and neoadjuvant chemotherapy with antitreatment is also indicated in early- stage disease.
HER2- directed
HER2-
HER2
The breast 387
https://t.me/medicina_free
Adjuvant radiotherapy
• Following wide local excision. Following BCS, such
as wide local excision for invasive cancer, radiotherapy to the breast significantly reduces the risk
of recurrence within the breast.
Following mastectomy. Post- mastectomy radio-
•
therapy decreases the risk of local recurrence in
risk patients. These include patients with
highlarge tumour size, highlymphatic invasion and/or involvement of deep
margins.
•
Following axillary surgery. After axillary sampling,
the axilla can be irradiated if low volume node
positive disease (1–2nodes). After axillary clearance, the axilla is not routinely irradiated. Addition
of radiotherapy to regional nodes, like the internal
mammary and the supra/infra clavicular nodes, is
usually indicated in extensive disease.
grade, nodal involvement,
Survival
Several factors are thought to have contributed to
increased survival rates for breast cancer, including
breast screening, specialist multidisciplinary teams
and more individualized treatment plans that
optimize each aspect of patient treatment. The overall
10-
year survival is now 76%, with 64% of all women
surviving for 20 years, although survival for individual
tumours depends on stage and type, as discussed.
Cancers detected by screening have a better prognosis (83% at 15 years), due to detection of early cancers and less aggressive forms of breast cancer.
Paget’s disease of
thenipple
Presentation
Paget’s disease
middle- aged and elderly women and is present in
around 2% of breast cancers. It presents as a unilateral
red, scaly or bleeding, eczematous lesion of the nip-
12
Sir James Paget (1814–1899), Surgeon, St Bartholomew’s
Hospital, London, UK. He also described diseases of the
bone and penis, and discovered the parasite of trichinosis in
humans while a rst- year medical student.
1112
of the nipple mostly occurs in
ple and areola, often accompanied by a burning sensation. Diagnosis is confirmed by punch biopsy.
Histologically, the epithelium of the nipple contains numerous ‘Paget cells’: large cells with clear
cytoplasm and small eccentric nuclei. It is associated
with an intraductal carcinoma of the underlying
breast in 50% of cases, and DCIS in many of the others; a mammogram with or without a breast MRI
should be part of the workup.
Treatment
Treatment will be determined by any underlying
breast carcinoma detected on clinical or radiological
investigation. Surgical management may include
mastectomy and axillary surgery if associated with
invasive cancer. In the absence of invasive disease, or
if a small central tumour lies close to the nipple, cone
excision of the nipple and underlying tissue followed
by breast radiotherapy may be considered.
Inflammatory breast
cancer
Inflammatory breast cancer is a rare, aggressive disease, representing only 0.5–2% of breast cancers. The
breast appears swollen, red, firm and warm to touch,
all cardinal features of inflammation. Symptoms
appear quite quickly as cancer cells block the small
lymphatics in the breast, and produce the peau
d’orange appearance. The majority of these tumours
will be ER negative. Treatment involves a combination of neoadjuvant chemotherapy, surgery (usually,
mastectomy and axillary clearance) and chest wall
radiotherapy. Prognosis is poorer; 5vival rates of the order of 50% and 30%, respectively,
although improvements are being made with the
introduction of new systemic treatments.
and 10- year sur-
Patients unfit forsurgery
These will usually be elderly patients with significant
comorbidity, and some may have locally advanced
tumours. The principles of management are closer to
those for metastatic disease, the aim of therapy being
to control the primary tumour while maintaining the
best quality of life. Many patients will respond to an
aromatase inhibitor or other hormonal therapy.
388 The breast
https://t.me/medicina_free
Metastatic disease
The aim of treatment is to prolong survival and control symptoms while maintaining a good quality of
life. All patients with metastatic disease should be
considered for some form of systemic therapy.
Receptors for ER and HER2 should be repeated at the
metastatic site and treatment should be directed
accordingly. Hormone therapy, chemotherapy and
HER2-
directed treatment can be used alone or in
combination. With the current advances, patients can
live for many years with metastatic breast cancer.
Prognosis is worse if the relapse is within 2 years from
initial diagnosis and if it involves visceral disease (i.e.
liver metastases).
As the disease progresses, patients may require
referral to palliative care specialists for control of
symptoms and to enhance support for patients and
carers.
Carcinoma ofthe
malebreast
This accounts for less than 1% of all cases of breast
cancer. In men, breast cancer affects an older age
group than in women, with a peak incidence at 60
years. Clinically, it usually presents as a firm, painless,
subareolar lump, although gynaecomastia and breast
tenderness may also be present. Most aspects of management have many similarities to that of women.
Treatment usually consists of a mastectomy due
to the limited amount of breast tissue, but a wide
local excision can also be performed if feasible. SLN
biopsy or axillary lymph node clearance is performed for node negative and node positive disease,
respectively.
Most tumours are oestrogen receptor positive, and
the recommended agent is tamoxifen for men if there
are no contradirected treatments, as well as radiotherapy, mirror
the indications applied to women.
Due to the rarity of male breast cancer, genetic testing is recommended for all newly diagnosed cases.
The prognosis for men is worse than for women,
probably because of the sparse amount of breast tissue present, which allows rapid dissemination of the
growth into the regional lymphatics.
indications. Chemotherapy and HER2-
Breast screening
Screening women aged 50–70 years with mammography every 3 years results in detection of early breast cancers and DCIS and a reduction in mortality, estimated to
be 1300 patients a year in the UK. Screencers tend to be smaller and node negative with an
increasing detection rate of in situ disease. Screening
may also detect some cancers that are very early and
slow growing that would probably not be problematic in
the woman’s lifetime, but this is outweighed by the
many other significant cancers that are detected (2 to
2.5lives saved for every over diagnosed case).
The success of the screening programme has led
toit being expanded to include women aged 47–73in
England, whereas emerging data suggest this to
be beneficial for women aged 40–49 years as well.
Screening may also start at an earlier age in women
who have a higher risk, due to family history or are
known carriers of high- risk genes; these patients are
offered yearly MRI scans from the age of 30 to 40 to
avoid repeated irradiation and improve accuracy due
to the increased breast density at this age.
detected can-
Prophylactic mastectomy
Women at high and very high risk for developing a
breast cancer may be offered prophylactic mastectomy. This includes women with a strong family history of breast cancer with or without a confirmed
inherited mutation (like BRCA1/2, TP53 genes). In
these cases, bilateral mastectomy can be discussed,
whereas contralateral prophylactic mastectomy can
be offered to women with a history of breast cancer
that remain high risk. The procedure may be either a
simple mastectomy or a subcutaneous nipple or skinsparing mastectomy with or without breast reconstruction. It is rarely possible to remove all breast
tissue so surveillance for this and other gene-
mutation- related cancers is necessary.
Additional resources
Case 97: A frightened girl with a breast lump
Case 98: Breast screening
Case 99: An ulcerating breast lesion
Case 100: A sinister break
Case 101: A woman with a sore nipple
The neck
https://t.me/medicina_free
Ekpemi Irune
Learning objectives
✓ To understand the dierent causes of neck lumps.
✓ To know about the origin, presentation and management of branchial
cysts.
38
The thyroid gland is considered separately in
Chapter 39, and the parathyroids in Chapter 40.
A summary of the possible causes of a lump in the
neck is given in Box38.1.
Branchial cyst andsinus
Anatomy
There are six arches and five clefts in the branchial
system (Figure 38.1). The first arch forms the lower
face, its external cleft the external auditory meatus,
and its internal cleft the Eustachian tube. The second
arch grows down over the third and fourth arches to
form the skin of the neck. Normally, there is no external cleft, while the internal cleft forms the tonsillar
fossa.
Aetiology
Persistence of remnants of the second branchial arch
may lead to formation of a branchial cyst, sinus or fistula. The external cleft remnants open just anterior to
the sternocleidomastoid, at the junction of the upper
one- third and lower two- thirds. A sinus or fistula
Ellis and Calne’s Lecture Notes in General Surgery, Fourteenth Edition.
Edited by Christopher Watson and Justin Davies.
© 2023 John Wiley & Sons Ltd. Published 2023 by John Wiley & Sons Ltd.
Companion website: www.wiley.com/go/Watson/GeneralSurgery14
represents a patent second branchial arch sinus,
which passes between the internal and external
carotid artery to the tonsillar fossa. That a branchial
cyst is a remnant of the second branchial arch has
been questioned, based on the observation that the
cysts are lined with stratified squamous epithelium
rich in lymphatic tissue. This countertheory suggests
that the cyst arises from cystic degeneration of lymphoid tissue in the neck and is thus better termed a
‘lateral cervical cyst’.
Clinical features
A branchial cyst usually presents in early adult life
and forms a soft swelling ‘like a halfbottle’, which bulges forward from beneath the anterior border of the sternocleidomastoid. It is lined by
squamous epithelium and contains pus- like material,
which is in fact cholesterol. It often presents following
an upper respiratory tract infection. Clinical diagnosis can be clinched by aspirating a few drops of this
fluid from the cyst and demonstrating cholesterol
crystals under the microscope. Occasionally, the cyst
may become infected.
Differential diagnosis is from a tuberculous gland
of the neck or from an acute lymphadenitis.
The rare first branchial arch cyst may present just
below the external auditory meatus at the angle of the
jaw, with extension closely related to the VII nerve.
A branchial sinus presents as a small orifice, discharging mucus, which opens over the anterior
filled hot water
390 The neck
https://t.me/medicina_free
Box 38.1 A lump inthe side ofthe neck
When considering the swellings that may arise in
any anatomical region, one enumerates the
anatomical structures lying therein and then the
pathological swellings that may arise from them.
The side of the neck is an excellent example of
thisexercise.
Skin and superficial fascia
•
Sebaceous cyst.
•
Lipoma.
Lymph nodes
•
Infective.
•
Malignant.
•
Lymphoma, lymphatic leukaemia (see Chapter36).
Lymphatics
•
Cystic hygroma.
Artery
•
Carotid body tumour.
•
Carotid artery aneurysm.
Neural elements
•
Neuroma– greater auricular neuroma.
•
Paraganglioma.
Salivary glands
•
Submandibular salivary tumours or sialectasis or
sialadenitis.
•
Tumour of the parotid gland.
Pharynx
•
Pharyngeal pouch.
Branchial arch remnant
•
Branchial cyst.
Bone
•
Cervical rib.
Other soft tissue and cartilaginous structures
•
Thyroid mass– goitre, thyroid cancer.
•
Parathyroid mass– adenoma or carcinoma.
•
Mass arising from the laryngeal cartilages–
laryngeal cancer.
border of the sternocleidomastoid in the lower part of
the neck. The majority are present at birth but a secondary branchial sinus may form if an infected
branchial cyst ruptures, or if part of the cyst is left
behind at operation. The sinus extends upwards
between the internal and external carotid arteries to
the sidewall of the pharynx. It may open into the tonsillar fossa (which represents the second internal
cleft) to form a branchial fistula.
Investigation
In patients over the age of 40 years, cystic lymph node
metastases should be considered. It is also not
uncommon for squamous cell carcinomas of human
papilloma virus (HPV) type to present with cystic
cervical lymph nodes in younger patients. Caution
should be paid to obtaining a full clinical history,
thorough oropharyngeal examination and flexible
nasolaryngoscopy. Crossneck (by CT or MRI scan), ultrasound characterization of the neck lump combined with fineaspiration cytology or core- biopsy are essential to
exclude malignancy in this patient group.
sectional imaging of the
needle
Treatment
Where no evidence of tumour is found on imaging
and biopsy of the branchial cyst, the patient may
undergo a neck dissection alone. Where there
remains suspicion of malignancy, the neck dissection
is undertaken in conjunction with a pharyngoscopy
to examine the upper aero- digestive tract for a primary cancerous lesion, bilateral tonsillectomy and a
tongue base mucosectomy. All specimens from surgery are sent for histological analysis to confirm the
pathological diagnosis.
Tuberculous cervical
adenitis
Once an extremely rare disease in the UK, a diagnosis
of tuberculosis (TB) was made in over 8 900 people in
the year 2011. Actively raising awareness, surveillance
and comprehensive treatment in affected individuals
has ensured that new cases of TB in the UK have fallen
to the lowest levels since records began in 1960: dropping to approximately 4458 cases in 2020. Individuals
at risk of contracting TB include the elderly, the
immunocompromised, non- immunized migrants
from countries with high a incidence of TB, deprived
individuals residing in crowded conditions, those
with high risk lifestyles such as drug and alcohol
Pouch I
https://t.me/medicina_free
Eustachian tube
and middle ear
The neck 391
1
Pouch II
Tonsil
Pouch III
Inferior
parathyroid
and thymus
Pouch IV
Superior
parathyroid
2
3
4
dependence, and cases that arise due to unexpected
contact with infected individuals.
Cervical nodes are usually secondarily involved
from a focus originating in the upper aero-
digestive
tract such as the tonsils and adenoids. The dental
roots may occasionally be the primary source of infection. The organisms may be human or bovine, and
occasionally the disease is secondary to active pulmonary infection (pulmonary TB). The upper jugular
chain of lymph nodes is most commonly affected in
pulmonary and extra-
pulmonary TB.
Clinical features
At first, the nodes are small and discrete; then, as they
enlarge, they become matted together and caseate
with abscess formation, which eventually bursts
through the deep fascia into the subcutaneous tissues. This results in a pocket of pus deep to and
another superficial to the deep fascia, both connected
by a small track: a ‘collar stud’ abscess. Left untreated,
this discharges onto the skin, resulting in a chronic
tuberculous sinus.
Differential diagnosis
Extra- pulmonary TB commonly affects lymph
nodes, especially in the neck. Solid nodes must be
differentiated from acute lymphadenitis, lymphoma
or secondary malignant deposits. The abscess
Foramen
caecum
Thyroid
Figure38.1 The derivatives of the
branchial pouches and clefts. Reproduced
from Ellis H, Mahadevan V (2010)
Clinical Anatomy, 12
Wiley- Blackwell.
th
edn. Oxford:
originating from a necrotizing lymph node must be
differentiated from a branchial cyst (see earlier in
this chapter).
Diagnosis may be facilitated with the use of ultrasound scan, as the chronic tuberculous nodes show
flecks of calcification and core needle biopsy samples
may be obtained simultaneously for microbiological
and histological analysis.
Treatment
The mainstay of TB treatment is non- surgical. Input
from Infectious Diseases clinicians and the respiratory physicians should be sought in the management of these patients. Most institutions have a
specialist team dedicated to overseeing the investigation and management of patients with suspected
tuberculosis within a multidisciplinary setting. The
decision to treat is taken by experts in TB management and includes a full course of multi- drug antituberculous chemotherapy. Small nodes are treated
conservatively and the patient is kept under observation. Significantly enlarged nodes greater than
3cm with significant abscess burden and/or fistula
may be treated surgically with neck dissection in
tandem with ongoing TB chemotherapy. This should
only be offered in selected cases in discussion with
the primary TB team due to the risk of creating a
non- healing wound in an already immunocompromised patient.
392 The neck
https://t.me/medicina_free
Carotid body tumour
(chemodectoma)
Pathology
Also called carotid glomus tumours or carotid paragangliomas, these are slowarise from the chemoreceptor cells in the carotid
body at the carotid bifurcation. Most behave in a
benign fashion; in a few patients, the tumour becomes
locally invasive and may metastasize. There is a familial tendency to development of the tumour. They may
also occur sporadically.
Macroscopically, it is a lobulated, yellowish tumour
closely adherent to the internal and external carotid
arteries at the bifurcation.
Microscopically, it is made up of large chromaffin
polyhedral cells in a vascular fibrous stroma.
Clinical features
The tumour presents as a slowly enlarging mass in a
patient over the age of 30 years, which transmits the
carotid pulsation. The mass itself may be so highly
vascular that it too demonstrates pulsation with a
bruit on auscultation. Occasionally, pressure on the
carotid sinus from the tumour produces attacks of
faintness. Extension of the tumour may lead to cranial
nerve palsies (VII, IX, X, XI and XII), resulting in dysphagia and hoarseness.
growing tumours that
the carotid artery, the bifurcation of which is
splayed open by a richly vascularized mass.
•
Genetic Testing for the patient and family mem-
bers should be carried out via referral to the
Medical Genetics team. This is specifically aimed
at uncovering tendency to and diagnosis of further
paraganglioma in patients found to have genetic
mutations. Approximately a quarter of paragangliomas are hereditary, with mutations in genes
associated with succinate dehydrogenase.
Treatment
These cases are usually managed within a multidisciplinary team (MDT) of surgeons, geneticists, radiologists, pathologists, endocrinologists and other allied
healthcare professionals.
Where surgery is offered, it is often possible to dissect the tumour away from the carotid sheath. If the
carotid vessels are firmly involved, resection can be
performed with graft augmentation or replacement of
a segment of the artery. There is a risk of up to 5%
ofcerebrovascular complications, including a higher
risk of damage to adjacent cranial nerves. Thus,
patients must be counselled appropriately and the
option of conservative management with surveillance scanning may even be offered.
In the elderly, slow- growing tumours can be left
untreated. In other cases, stereotactic radiosurgery
may be offered to arrest the growth of the tumour.
This may be by way of targeted radiotherapy in more
recent times, with the benefits being the avoidance of
surgery and its potential life- changing complications.
Special investigations
• Duplex ultrasound gives precise localization of the
tumour and its relation to the carotid and its
bifurcation.
• Magnetic resonance imaging and computed
tomography show the tumour and its relation to
Additional resources
Case 102: A painless lump in the neck
Case 103: A young immigrant with a lump in the
neck
The thyroid
https://t.me/medicina_free
Brian Fish
Learning objectives
✓ To know the embryological course of the thyroid and related remnants.
✓ To understand the management of benign and malignant thyroid
conditions.
Congenital anomalies
Embryology
The thyroid gland forms as a diverticulum originating in
the floor of the pharynx, and descends through the
tongue, past the hyoid bone, to its position in the neck.
The diverticulum usually closes, leaving a pit at the base
of the tongue (the foramen caecum, which lies in the
midline at the junction of the anterior two- thirds and the
posterior third of the tongue). Failure of the thyroid to
descend or incomplete descent along the track may result
in ectopic thyroid tissue (Figure39.1). Incomplete obliteration of the track may result in fistula or sinus formation.
In all cases of unexplained midline nodules in the neck,
thyroid tissue should be suspected. A neck ultrasound
with or without a thyroid uptake scan should be considered before removal of any ectopic thyroid tissue to
ensure that there is normal thyroid tissue present in the
correct place before the ectopic thyroid tissue is removed.
39
of the tongue. This is termed a ‘lingual thyroid’, and
usually represents the sum total of thyroid tissue.
Treatment may not be required, although it can cause
obstructive symptoms and rarely can undergo malignant
change. Treatment with levothyroxine may suffice
if associated with hypothyroidism and occasionally
excision may be required.
Thyroglossal cyst
A thyroglossal cyst forms in the embryological remnants of the thyroid and presents as a fluctuant swelling in or near the midline of the neck. It is diagnosed
by its characteristic physical signs.
1
It moves upwards when the patient protrudes the
tongue, because of its attachment to the tract of
the thyroid descent.
2 It moves on swallowing, because of its attachment
to the larynx by the pretracheal fascia.
Lingual thyroid
Rarely, the thyroid fails to descend into the neck. Such
a patient presents with a lump at the foramen caecum
Ellis and Calne’s Lecture Notes in General Surgery, Fourteenth Edition.
Edited by Christopher Watson and Justin Davies.
© 2023 John Wiley & Sons Ltd. Published 2023 by John Wiley & Sons Ltd.
Companion website: www.wiley.com/go/Watson/GeneralSurgery14
Treatment
Such cysts should be removed surgically, together
with remnants of the thyroglossal tract, up to the foramen caecum and the body of the hyoid bone, to which
the tract is closely related (Sistrunk’s procedure
1
Walter Ellis Sistrunk (1880–1930), Associate Professor
of Surgery, Mayo Clinic, Rochester, MN. Described the
procedure in 1928.
1
).
394 The thyroid
https://t.me/medicina_free
Lingual
thyroid
Hyoid
cartilage
Suprahyoid
thyroglossal cyst
Thyroid
cartilage
There is an associated risk of malignancy of approximately 1%. Infection of the cyst or incomplete excision
can lead to a thyroglossal fistula.
Track of thyroid
descent and of a
thyroglossal fistula
Thyroglossal cyst
or ectopic thyroid
Pyramidal lobe
Retrosternal goitre
Thyroid physiology
The thyroid gland is concerned with the synthesis of
the iodine- containing hormones thyroxine (tetraiodothyronine, T4) and tri- iodothyronine (T3), which
control the metabolic rate of the body; T3 is the active
hormone and T4 is converted to T3 in the periphery.
The thyroid gland also secretes calcitonin from the
parafollicular C cells, which reduces the level of serum
calcium and is, therefore, antagonistic to parathormone.
Iodine in the diet is absorbed into the bloodstream
as iodide, which is taken up by the thyroid gland. After
entering the follicle, the iodide is converted into
Figure39.1 The descent of the
thyroid, showing possible sites of
ectopic thyroid tissue or thyroglossal
cysts, and also the course of a
thyroglossal stula. (The arrow shows
the further descent of the thyroid that
may take place retrosternally into the
superior mediastinum.)
organic iodine, which is then bound with the tyrosine
radicals of thyroglobulin to form the precursors of the
thyroid hormones. The colloid within the thyroid vesicles is composed of thyroglobulin, which is synthesized in the follicular cells, and T3 and T4. These
hormones are released into the bloodstream after
being separated from thyroglobulin within the follicular cells. In the general circulation, about 99% of
T3and T4 is bound to protein, and it is the minute
amount of unbound ‘free’ thyroid hormones in the
circulating blood that produces the endocrine effects
of the thyroid gland.
Physiological control ofsecretion
The immediate control of synthesis and liberation of
T3 and T4 is by thyroid- stimulating hormone (TSH)
produced by the anterior pituitary. TSH is secreted in
Соседние файлы в папке Библиотека им академика М.И. Перельмана