Breast and Endocrine
CASE 41: a painleSS lump in the neCK
history
A 40-year-old woman has been referred to the surgical outpatients with a painless lump in the neck. She had noticed the lump 2 weeks previously when looking in the mirror. She had not noticed any other lumps and does not complain of any other symptoms. She has not gained or lost any weight recently, and her bowel habit has remained normal.
examination
Examination reveals a solitary 2 × 2-cm swelling to the left of the midline just above the manubrium. The swelling is firm, smooth and fixed. The swelling moves on swallowing, but does not move on protrusion of the tongue. There are no associated palpable lymph glands. General examination reveals no further abnormalities.
INVESTIGATIONS
|
|
Normal |
haemoglobin |
12.0 g/dl |
11.5–16.0 g/dl |
mean cell volume |
77 fl |
76–96 fl |
White cell count |
10.4 × 109/l |
4.0–11.0 × 109/l |
platelets |
250 × 109/l |
150–400 × 109/l |
Sodium |
137 mmol/l |
135–145 mmol/l |
potassium |
3.7 mmol/l |
3.5–5.0 mmol/l |
urea |
5 mmol/l |
2.5–6.7 mmol/l |
Creatinine |
71 μmol/l |
44–80 μmol/l |
tSh |
0.62 mu/l |
0.5–5.7 mu/l |
Free t3 |
3.4 pmol/l |
2.5–5.3 pmol/l |
Free t4 |
19 pmol/l |
9–22 pmol/l |
Questions
•What is the differential diagnosis for a lump in the anterior triangle of the neck?
•Where is this lump likely to be originating from?
•What steps would you take in the assessment of this lump?
•Which factors may suggest malignancy?
•What are the most common types of malignancy?
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100 Cases in Surgery
ANSWER 41
!Differentials for a swelling in the anterior triangle of the neck
•Multiple: lymph nodes
•Solitary: does it move with swallowing?
•Yes:
−thyroid origin
−thyroglossal cyst (moves with protrusion of the tongue)
•No:
−Salivary gland
−Dermoid cyst
−Carotid body tumour
−lymph node
−branchial cyst
−Cold abscess (tuberculosis)
Clinical examination indicates that the swelling is likely to be a palpable thyroid nodule. The majority of patients are clinically euthyroid and have normal thyroid function. The presence of abnormal thyroid function suggests a benign diagnosis. Factors that increase the suspicion of malignancy include:
•Age younger than 20 years or older than 70 years
•Male sex
•Recent origin and rapid growth or increase in size
•Firm, hard, or immobile nodule
•Presence of cervical lymphadenopathy
•Associated symptoms of dysphagia or dysphonia
•History of neck irradiation
•Prior history of thyroid carcinoma or a positive family history
Less than 20 per cent of thyroid nodules are malignant, with the majority being cystic or benign. Many solitary thyroid nodules are dominant nodules in a multinodular goitre, which carry a 5 per cent risk of malignancy. Ultrasound is used to distinguish between solid and cystic nodules as well as differentiating a solitary nodule from a dominant nodule in a multinodular goitre. Fine-needle aspiration has a high sensitivity and specificity for distinguishing benign from malignant lumps in the thyroid. The main limitation of fine-needle aspiration is in the differentiation of benign follicular adenoma from malignant follicular cancer. If a follicular neoplasm is diagnosed on fine-needle aspiration, the lesion will need to be fully excised to exclude malignancy. Radio-isotope scanning provides a functional assessment of the thyroid nodule, which can be classified as cold or hot. Most solitary thyroid nodules are cold, with a risk of cancer at around 20 per cent.
Table 41.1 Types of thyroid cancer
Type |
Frequency |
Age (years) |
Behaviour |
Prognosis |
Papillary |
70 per cent |
20–40s |
Slow growing, lymphatic |
good, approximately 80 |
|
|
|
spread to nodes |
per cent 10-year survival |
Follicular |
20 per cent |
35–50s |
bloodstream spread, |
good, approximately 60 |
|
|
|
metastasises to lung or |
per cent 10-year survival |
|
|
|
bone |
|
Anaplastic |
5 per cent |
60–70s |
aggressive, local spread |
poor, approximately 10 |
|
|
|
|
per cent 10-year survival |
Medullary |
5 per cent |
Familial |
From parafollicular C |
|
|
|
|
cells, associated with the |
|
|
|
|
multiple endocrine neo- |
|
|
|
|
plasia (men) syndrome |
|
|
|
|
|
|
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Breast and Endocrine
KEY POINTS
•less than 20 per cent of thyroid nodules are malignant.
•Follicular adenomas should be excised to rule out malignancy.
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