Endo/Neuroendo/Urol Flashcards
How should patients with suspected pheochromocytoma be initially investigated?
Plasma free metanephrines (from supine position) and/or urinary fractionated metanephrines
Note this is not vanillymandelic acid (VMA) - which has a high false positive rate
(Endocrine Society Clinical Practice Guidelines 2014)
When is a MIBG scintigraphy indicated in management of phaeo/paraganglioma?
With metastatic disease when radiotherapy using I-MIBG is planned, otherwise use PET-CT
(Meta-iodobenzylguandidine)
(Endocrine Society Clinical Practice Guidelines 2014)
What germline mutation should be tested for in patients with Paragangliomas?
Succinate dehydrogenase (SDH) - about 50% prevalence if present
(Endocrine Society Clinical Practice Guidelines 2014)
How should functional phaeochromocytomas/paragangliomas be managed in the preoperative setting?
A-adrenergic blockers first choice, allowing 7-14 days prep.
Advice re high sodium/fluid diet (to combat intravascular depletion post op)
(Endocrine Society Clinical Practice Guidelines 2014)
A blockers - phenoxybenzamine (irreversible), phentolamine, doxazosin
Often give beta blockade after establishing alpha blockade (labetolol)
How should patients with resected PPGL be monitored?
Annual plasma/urine metanephrines
(Endocrine Society Clinical Practice Guidelines 2014)
When should an open approach be taken to resection of pheochromocytoma?
Large >6cm, invasive tumours - minimise rupture, complete margins
Most paraganlgiomas
Partial can be considered rarely
(Endocrine Society Clinical Practice Guidelines 2014)
How does a phaeochromocytoma differ from a Paraganglioma?
Phaeo is tumour arising adrenomedullary chromatin cells (producing one or more of epinephrine, norepinephrine and dopamine) - about 80-85%.
Paraganglioma 15-20% - extra-adrenal chromatin cells of sympathetic paraveterbral ganglia of thorax, abdomen and pelvis. Can also arise from parasympathetic ganglia along IX and X nerves and base of skull - do not produce catecholamines
What is the prevalence of PPGL among adult hypertensive outpatients?
0.2-0.6% — 1.7% children
5% of incidental adrenal masses
Which syndromes are associated with PPGL?
MEN2a - MTC, HPTH, lichen amyloidosis
MEN2b - MTC, neuromas, intestinal gangliomas (Hirschprungs)
vHL - HAemangiomblasoma, retinal angioma, clear cell RCC, pancreatic NETs and cyst adenomas, papillary cyst adenomas of epididymis
NF1 - neurofibromas, cafe-au-lait spots, freckling, iris harmartomas (Lisch nodules)
What proportion of phaeochromocytomas are bilateral?
10%
10% children, 10% malignant, 10% not hypertensive
How are appendiceal neuroendicine neoplasms most frequently detected?
Incidentally during appendicectomy
(ENETS consensus guidelines 2016)
Which patients with incidentally identified neuroendocrine tumours at appendicectomy do not require further treatment?
<1cm size
Invasion up to subserosa or up to 3mm in mesoappendix
clear surgical margins
Those at base or larger also more likely to recur
(ENETS consensus guidelines 2016)
Where do appendiceal NENs most often appear?
70% at tip
What tumour markers are useful in appendiceal NEN?
Chromogranin A (CgA) - useful to differentiate from goblet cell carcinoma, follow up with metastatic
urinary 5-HIAA in rare patients with carcinoid
(ENETS consensus guidelines 2016)
How are Neuroendocrine tumours graded?
WHO 2010 classification
Ki67 Index (%) and Mitotic Rate (HPF)
G1 NET - Ki ≤2%, MR <2/10
G2 NET - KI 3-20%, MR 2-20/10
G3 NET - KI >20, MR >20
G3s - either poorly differentiated or carcinoma
What is the metastatic rate for appendiceal NETS >2cm?
about 40%
When should a right hemicolectomy be considered with appendiceal NETs 1-2cm in size?
if Base or R1,
or if risk factors - V1,L1, G2/3
(ENETS consensus guidelines 2016)
How often do small intestinal NETs present with metastasis?
50%
How do metastatic small intestinal NETs usually present?
With vague nonspecific symptoms - the carcinoid syndrome is still rare
What symptoms are associated with Carcinoid syndrome?
Secretory diarrhoea (60-80%)
Flushing (60-85%)
Intermittent bronchial wheezing (<10%)
Right heart valve fibrosis - Carcinoid Heart disease, Hedinger syndrome (20%)
Seen with liver metastatic disease bypassing hepatic clearance of serotonin
5% of patients can have retroperitoneal/ovarian tumours/metastases
How should patients be optimally investigated for small intestinal NET?
CT/MRI followed by Ga-DOTATOC PET or SRS Spect
For G3 a FDG PET may be useful
(ENETS consensus guidelines 2016)
What biochemical tests are useful in SI NETs?
Serum Chromogranin A
Urinary 5-HIAA (product of serotonin metabolism) highly sensitive
What are the types of well differentiated gastroduodenal NETs? (3)
Type 1 - ECLoma (Enterochromaffin like cell) - chronic atrophic gastritits
Type 2 - ECLoma -Zollinger Ellison
Type 3 - rare, sporadic, often high grade
If <1cm - endoscopic resection
How should rectal NETs be managed?
If <1cm - Endoscopic resection (unless G3)
>2cm - Anterior resection
1-2cm variable
(ENETS consensus guidelines 2016)
How is Zollinger Ellison syndrome diagnosed?
Elevated fasting serum gastrin (x10 normal) in the presence of hypergastrinaemia when gastric pH<2
60-80% in duodenum (90-100% in those with MEN1)
(ENETS consensus guidelines 2016)
How is an insulinoma diagnosed? (4)
Plasma glucose <3mmol
Plasma insulin ≥3uU
C-peptide ≥0.6ng
Proinsulin ≥5pmol
For non-functioning p_NETs Chromogranin A can be useful
How should pNETs be localised?
68GA labelled somatostatin analog
PET-CT is better than SR SPECT, except for insulinoma - GLP1-receptor analogue scintigraphy or intra-arterial injection and measurement of some gradient
What surgical approach can frequently be used for insulinoma?
Enucleation
When should non-functioning P-nets be excised?
≥2cm when major pancreatic resection required
What are the types of appendiceal neoplasm?
1) Mucinous epithelial neoplasm
-Serrated polyp
-Low grade Mucinous neoplasm (LAMN)
-High grade mucinous neoplasm (HAMN)
-Mucinous adenocarcinoma
2) Non-mucinous epithelial neoplasm (adenoma/adenocarcinoma)
3) Epithelial with neuroendocrine features (NET or Goblet cell)
4) Mesenchymal neoplasms
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What are the types of appendiceal neoplasm?
1) Mucinous epithelial neoplasm
-Serrated polyp
-Low grade Mucinous neoplasm (LAMN)
-High grade mucinous neoplasm (HAMN)
-Mucinous adenocarcinoma
2) Non-mucinous epithelial neoplasm (adenoma/adenocarcinoma)
3) Epithelial with neuroendocrine features (NET or Goblet cell)
4) Mesenchymal neoplasms
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What tumour markers should be measured in appendiceal PMP?
CEA + CA19-9 +/- CA125
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What is the risk of synchronous tumours when colonic cancer is diagnosed?
3-5%
When should a right hemicolectomy be performed for goblet cell carcinoma of the appendix?
Any of:
Not Tang A
Tumour ≥20mm
Involved margins
Mesoappendix invasion ≥3mm
V1/L1
Ki62>2%
If perforated consider adjuvant CRS/HIPEC
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
If a pseudomyxoma is suspected as an incidental finding at surgery, how should it be managed?
Appendicectomy (?caecetomy?lymph node resection) + sampling of mucin
Avoid right hemicolectomy
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
In patients where pseudomyxoma is suspected who are undergoing a laparoscopy, where should trocars be placed?
In the midline, so incisions can be excised
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
When is CRS/HIPEC indicated with a completely excised LAMN?
pM1a/pM1b - acellular/cellular mucin PCI≤3
A right hemicolectomy is not indicated
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
When should a right hemicolectomy be performed with a HAMN?
Probably in all cases, definitely if perforated.
Similar for CRS and HIPEC
Also for mucinous adenocarcinoma and GCC
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What defines complete cytoreduction?
CC0 - no visible disease or
CC1 - remaining nodules <2.5mm
achieved in 73.8% –> 87.4% 5 year survival
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What are the absolute (2) and relative (6) contraindications to cytoreductive surgery?
Absolute:
- Extensive small bowel serosal involvement
- Mesenteric involvement causing retraction
Relative:
- Age>75
- Aggressive histologies - high grade with signet ring, mucinous, GCC, PCI>20
- Involvement of liver hilum
- Infiltration of anterior pancreatic surface
- Ureteric obstruction
- Need for total gastrectomy
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
How should ovaries be managed in patients with appendiceal PMP?
In postmenopausal women bilateral salpingoophrectomy, probably in premenopausal too
(Peritoneal Surface Oncology Group International (PSOGI) Guidelines 2021)
What imaging is indicated for patients with suspected primary hyperparathyroidism?
Usually Ultrasound and Sestamibi scan.
SPECT may be useful, particularly if reoperation is being considered
If not localised or scans discordant, consider 4 gland exploration anyway, no need for further scans first.
NICE (2019)
How can primary hyperparathyroidism be differentiated from familial hypocalciuric hypercalcaemia?
24 hour urinary calcium excretion or
random renal calcium:creatinine excretion ratio
Random serum calcium:creatinine clearance ratio (>0.01)
NICE (2019)
When should surgery be considered in patients with primary hyperparathyroidism?
adjusted Ca>2.85 or
symptoms of hypercalcaemia or
end organ disease (renal stones, fragility fractures or osteoporosis - t score -2.5 or less
How should patients be followed up after parathyroidectomy?
adjusted Ca and PTH before discharge
adjusted Ca at 3-6 months and then annually if normal
When is cinacalcet indicated for primary hyperparathyoidism?
If surgery failed or inappropriate and:
aCa>2.85 + symptomatic
aCa>3 regardless
Why does a thyroglossal cyst move on extension of tongue?
Arises from descent from foramen cecum of tongue
What are the likely positions of the superior parathyroid gland?
1) In fat pad on thyroid surface caudal to inferior thyroid artery
2) Inferiorly behind inferior thyroid artery and oesophagus
3) behind upper pole
What are the likely positions of the inferior parathyroid gland?
1) Along thyrothymic axis (30%)
2) Under capsule of lower thyroid pole (50%)
3) down to accessible mediastinal thymus
4) within carotid sheath
5) intrathymic
6) within thyroid lobe
What is the recommended first line treatment for Graves disease?
If mild and uncomplicated –> Carbimazole (12-18months) or radioiodine
If severe radio iodine
Surgery, only if concerns re compression, malignancy or others unsuitable
NICE (2019)
What is the recommended first line treatment for toxic nodular goitre?
Radioactive iodine.
If unsuitable, total thyroidectomy or antithyroid drugs
NICE (2019)
When should propylthiouracil be considered over carbimazole?
- patients with allergy to carbimazole
- pregnant or within 6 months
- history of pancreatitis
Do not use either if history of agranulocytosis
NICE (2019)
What is Conns syndrome?
Primary aldosteronism - 33% adenoma, 66% bilateral adrenal hyperplasia
For adenoma –> surgery, bilateral –> spironolactone
Present with hypertension, depressed renin-angiotensin axis, hypokalaemia (increased urinarly losses)
Plasma aldosterone:renin ratio is diagnostic
about 5-10% of hypertensive patients
What is the embryological origin of the inferior parathyroids?
Third pharyngeal pouch, along with the thymus
Supplied by glossopharyngeal nerve (IX)
What is the embryological origin of the superior parathyroids?
Fourth pharyngeal pouch, along with parafollicular thyroid C-cells + larynx
supplied by superior laryngeal nerve (vagus derivative)
What is the staging peculiarity for patients with differentiated thyroid cancer?
Patients under 45 are all stage 1 if M0 and stage 2 if M1.
Stages 1-3 have a 10 year survival of >98%
What is the incidence of permanent recurrent laryngeal nerve injury after total thyroidectomy?
0.2%
2% risk of permanent hypocalcaemia
What proportion of patients with sporadic hyperparathyroidism have a single adenoma to explain their symptoms?
85%
What is the most useful biomarker of medullary thyroid disease?
Calcitonin - derived from the parafollicular C-cells
Can be used to screen in familial cases and monitor for metastatic disease
What proportion of patients with an adrenal nodule <4cm will have a carcinoma?
2%
25% >6cm
Age, sex, FH and functional studies are not a reliable indicator of malignancy
What is the incidence of pheochromocytoma in adrenal incidentalomas?
about 5%
30% of phaeos are diagnosed in this fashion
What is the genetic abnormality in Li-Fraumeni syndrome?
Autosomal dominant p53 mutation
- Sarcoma
- Breast cancer
- Leukaemia
- Adrenocortical adenocarcinoma
SBLA syndrome
What are the common manifestations of MEN-1?
Parathyroid, pituitary and pancreatic tumours, foregut carcinoids
What are the common manifestations of MEN2a?
Parathyroid adenomas, Medullary thyroid cancer, pheochromocytoma
RET oncogene mutation
What are the common manifestations of MEN2b?
Mucosal neuromas, marfinoid habitus, Medullary thyroid cancer, pheochromocytoma
RET oncogene mutation
How is malignant phaeochromocytoma diagnosed?
Requires presence of distant metastases
Likelihood is increased by 3+ of Weiss criteria.
What is the other name for Chronic Lymphocytic thyroiditis?
Hashimotos disease (hypothyroidism, elevated thyroid autoantibodies)
What is deQuervain’s thyroiditis?
Post viral thyroiditis - treat with NSAIDs +/- beta blockers if necessary
What is Reidel’s thyroiditis?
Woody hard swelling of thyroid as an isolated abnormality
F>M
Usually treat with high dose steroids
Which type of thyroid cancer characteristically metastasises by the haematogenous route?
Medullary
When does tertiary hyperparathyroidism require surgery?
If persists >12 months beyond resolution of CRF - about 40%
How are thyroglossal cysts best treated?
Due to recurrent infection, formal excision with part of hyoid bone (Sistrunk procedure)
What is the gender disparity of thyroid nodules?
5:1 F:M
What are risk factors for a thyroid nodule being malignant?
- Age <20 or >60
- ‘Firmness’
- Rapid growth
- Fixation to adjacent structures
- Vocal cord paralysis
- Lympadenopathy
- History of neck irradiation
- History of Hashimotos (lymphoma)
When should a core biopsy of a thyroid lump be performed?
If lymphoma is suspected, otherwise FNAC
How are USS findings for thyroid nodules graded?
U1-U5
FNAC for 3-5, discharge 1-2 unless other risk factors
How are thyroid nodule FNACs categorised?
Thy 1 - non diagnostic –> repeat
Thy 2 - benign –> no follow up
Thy 3F - follicular lesion –> hemithyroidectomy (with isthmus) or total thyroidectomy
Thy 3A - atypia -> repeat, if still present –> hemithyroidectomy
Thy 4 - suspicious –> diagnostic hemithyroidectomy
Thy 5 - malignant –> total thyroidectomy
In PTC/FTC, when is hemithyroidectomy sufficient?
<4cm, age <45, no other high risk factors (inc not pT3/T4a)
When should a level 6 lymph node dissection be conducted in PTC?
High risk cancers, or if lateral or other nodes confirmed to be involved
Cervical lymph nodes should be managed by selective node dissection
For FTC, only conduct level 6 nodal dissection if nodes are clinically involved
What treatment do patients require after total thyroidectomy for cancer?
Suppressive doses of levothyroxine 20ug/kg or liothyronine
Calcium check within 24 hours
Thyroglobulin >6weeks post surgery and then 6-12 monthly
When is I131 ablation performed after total thyroidectomy for cancer?
In all cases, unless tumour <1cm or minimally invasive with either no high risk papillary forms or medullary
What proportion of cases of medullary thyroid cancer are familial?
25% (MEN2a, MEN2b, Familial MTC) - therefore screening for RET mutation
Where MTC is suspected what preoperative investigations are required?
Calcitonin, CEA
Urinary metanephrines (24hr)
Calcium and PTH
CT/MRI/USS neck
RET (?after surgery)
What is the recommended surgical treatment of medullary thyroid cancer?
Total thyroidectomy with central compartment node clearance (level 6), even in the presence of disseminated metastasis
If there are central lymph node metastasis, ipsilateral neck dissection should be performed (70% involved)
All T2-T4 tumours also have bilateral selective neck dissections (IIa-Vb)
What USS features are suggestive of thyroid malignancy?
Hypoechoity
Microcalcifications
Lymphadenopathy
Loss of halo
Irregular margins
What are the histological features of papillary thyroid cancers?
Most common sub type
Psammoma bodies (microcalfication)
Orphan Annie Nuclei
Metastasise via lymphatics
What are the skin manifestations of Glucagonoma?
Necrolytic migratory erythema (70%)
(erythematous blisters of abdomen/buttocks with irregular border and intact/ruptured vesicles)
Serum glucagon of >1000pg/ml
produced by alpha cells
90% malignant
How should incidental adrenal lesions be managed?
75% non-functioning adenomas
Risk of malignancy related to size - if >4cm, 25% malignant
If suspected metastasis then biopsy as long as not phaeo
Otherwise excise or monitor
Also needs:
Cortisol (morning/midnight)
1mg overnightDexamethasone suppression test - Cushing?
24 hour urinary cortisol and metnephrines - Phaeo
Serum potassium (low) aldosterone (high) and renin (low) levels - Conns
What is the risk of hypocalcaemia following thyroidectomy?
5% requiring treatment, 80% resolve over 12 months (therefore 1-2% at 12 months)
Which tumour type is most likely to metastasise to the thyroid?
Renal cell carcinoma - clear cell morphology
How does PTH cause its effects?
Secreted by parathyroid chief cells
Increases calcium level by:
Bone - Osteoblast binding –> osteoclasts –> bone resorption
Kidney - active reabsorption of ca and mg from distal convoluted tubule
Intestine via kidney - increasing activated Vitamin D
Increases activity of 1-a-hydroxylase enzyme (converts 25-hydroxycalciferol to 1,25-dihydroxycholecalciferol)
Which antibiodies are seen in patients with Hashimotos and Graves disease?
Hashimotos - Thyroid peroxidase (100%)
Graves - Thyroid peroxidase (70%), TSH receptor (95%)
For patients with suspected parathyroid cancer on USS, what is the optimum treatment?
Straight to surgery, no tissue diagnosis.
Hemithyroidectomy + gland - 89% 5 year survival
Gland only 53% 5 year survival
How does Aldosterone exert its effects?
Produced by Zona glomerulosa of adrenal
Controls sodium reabsorption in distal renal tubule via Na+/K+ and H+ pumps
Where are thyroglossal cysts most commonly found?
Immediately Inferior to hyoid bone
What are the types of Cushings syndrome?
ACTH dependent - pituitary (Cushing disease) or ectopic (mostly lung ca)
ACTH independent - adenoma/carcinoma of adrenal
How is Cushings disease investigated?
24 hour urinary cortisol
Dexamethasone suppression test (CT/MRI)
What medical treatment is effective for advanced/mestastatic adrenal cortical cancers?
Mitotane
What histological findings are often seen in Follicular carcinoma of the thyroid?
Hurthle cells (adverse prognosis)
What is the most common presentation of Cushing syndrome?
Obesity 95%
Hirsuitism/hypertension 80%
Myopathy 60%
Buffalo hump 55%
Easy bruising 40%
Which thyroid tumour type is most common after non- therapeutic irradiation?
Papillary
What morphological charactestics on CT suggest a benign adrenal lesion?
Homogenous and lipid rich
HU<10 and less than 4cm, no further imaging
In patients with indeterminate adrenal lesions, what are indications for excision?
Increase in size by >20% + at least 5mm in 6-12 months
What additional tests should be performed for patients with bilateral adrenal nodules?
17-hydroxyprogesterone (exclude CAH)
What is the most common aetiology of an adrenal incidentaloma?
80% Adenoma (75% non functioning, 12% cortisol secreting, 2.5% aldosterone)
7% Phaeochromocytoma
8% Adrenocortical carcinoma
5% Metastasis
What are the chraracteristic findings of benign adrenal lesions on CT?
<4cm, <10Hu, >60% contrast washout
What enzymes are affected in CAH?
11a hydroxlase - aldo/test
17a hydroxylase - aldo
21ahydroxylase - test
What is the chloride to phosphate ratio in hyperparathyroidism?
Elevated, at >33
Which neuroendocrine tumours tend to present at youngest age?
Appendiceal - median 39 (39% male)
Most others are mid-late 60s
What is the most frequent type of NET?
Lung > SB > Appendix
Which NETs are more common in women (3)?
Appendix, caecum and lung
Women have a globally much better prognosis than males? why
What are the causes of diarrhoea in patients with NET (6)?
Pancreatic malabsorption
short bowel
drug related
bile salt related
bacterial overgrowth
hormonal (gastrin or 5-HT)
How should patients with NETS be managed perioperatively?
Consider octreotide IV/infusion
If non functioning - IV if major surgery
If history carcinoid will need IV for minor surgery (inc biopsies) and preop infusion for major
Where can NETs occur (3)?
1) Isolated neuroendocrine cells (bronchopulmonary, GI tract, skin)
2) Aggregates of neuroendocrine cells (pancreatic islets)
3) Classic endocrine glands (adrenal, pituitary)
What proportion of gastrointestinal NETSs are ‘functioning’?
about 30%
This is a difficult distinction though because they often release hormones when handled anyway
What proportion of patients with Small bowel NETs have carcinoid disease?
20% - 20% of these have carcinoid heart disease (check pro-BNP)
How long should patients with small bowel NETs be followed up for?
Minimum of 8 years - life
What is the differential diagnosis of an adrenal incidentaloma?
Functional
-cortex - adenoma, nodular hyperplasia, carcinoma
-medulla - phaeochromocytoma, ganglioneuroma/blastoma
Non-functional
-Adrenal masses - lipoma, cyst, haematoma, harmartoma, teratoma, amyloid, neurofibroma
-Metastases - breast, lung, lymphoma, renal
-Leukaemia
What investigations should be performed for an adrenal incidentaloma?
-Standard bloods
-Urinary/plasma metanephrines
-Overnight dexamethasone suppression test
-If hypertensive renin/aldosterone levels
-If virilised plasma sex steroids
What are the characteristics of a benign adrenal lesion on CT?
HU<10 and 60% contrast washout at 15 minutes
What are the indications for completion thyroidectomy after lobectomy for T3F?
If confirmed follicular carcinoma and any of:
Large tumour >4cm
Extracapsular extension/angioinvasion
Hurthle cell (secretes thyroglobulin)
What proportion of Insulinomas are benign?
About 90% therefore can be treated with enucleation. CF glucagonomas, which are usuallyy malignant
Best diagnostic test is EUS
5-10% have MEN1
75% of those with MEN1 will have Pancreatic Islet tumours
How should adrenal incidentalomas be assessed for cortisol excess?
1mg overnight Oral Dexamethasone test
If Cortisol <50 - normal
51-138 - possible
>138nmol/L probable (low ACTH)
What additional treatment will patients receiving Mitotane require?
Steroids - as lyses normal side as well
What proportion of U5 thyroid lesions are malignant?
80%
In which situations is monitoring of thyroglobulin inaccurate?
Remaining thyroid
Positive thyroid antibodies (can monitor trend)
What proportion of patents with Graves disease have eye signs?
30% - chemises, proptosis, opthalomplegia
(nb lid lag present in all thyrotoxicosis)
What are the broad indications for surgery in primary hyperparathyroidism?
Any <50
>50 if symptomatic or end organ damage
How often are Thy3f malignant on final histology?
About 20%
From which thyroid cells does thyroglobulin originate?
Follicular
Where is the largest store of body Calcium?
Bones!
What are the effects of PTH?
-To increase Ca and decrease PO4
-Immediate action on osteoblasts to increase Ca, also they signal the osteoclasts to resorb bone
-Increase renal tubular absorption of caclium
-Increased synthesis of 1,25(OH)2D –> bowel absorption
-Decreased renal phosphate
Where is Calcitonin made?
C- cells of thyroid
Which type of parotid malignancy has the worst outcomes?
Adenoid cystic (5 year 35%)
Acinic cell 80%, Adenocarcinoma up to 75%
Between which muscles does a pharyngeal pouch occur?
Thyropharyngeus and cricopharyngeus
From which branchial structure do branchial cysts originate?
2nd branchial cleft
What proportion of CO goes to the kidney?
About 25%
How is the GFR calculated?
(Conc of solute in urine x volume of urine/min)/plasma conc
Total volume of plasma leaving capillaries –> Bowman’s capsule
What substances are absorbed in the proximal convoluted tubule?
-Glucose, amino acid, phosphate co-transported with Na+ and water
- Up to 2/3 of water
What substances are regulated at the distal convoluted tubule?
Sodium
Potassium
H+
Calcium
Describe the physiology of the Loop of Henle?
-Isotonic fluid enters LoH
-Thin descending limb permeable to water but not Na/CL
-Thin ascending limb impermeable to water but permeable to ions
-Thick ascending limb active resorption of na and cl ions
What factors stimulate renin release?
From juxtaglomerular cells –> angiotensinogen to angiotensin 1
-Hypotension (reduced RPP)
-Hyponatraemia
-Sympathetic nerve stimuation
-Catecholamines
-Erect posture
What drugs reduce renin secretion?
Beta blockers
NSAIDs
What factors are likely to make postoperative renal failure more likely?
-Elderly
-PVD
-High BMI
-COPD
-Vasopressors
-Nephrotoxic medication
-Emergency surgery
What are the characteristics of prerenal renal failure?
Kidneys retain sodium,
Therefore
Urine sodium low (<20mmol/l)
Urine concentrated (>1.5 osmolality ratio) with high SG
What are the types of testicular cancer?
95% Germ cell tumours
- Seminoma (commonest)
-NSGT (42% - teratoma, yolk sac, choriocarcinoma, mixed germ cell)
What are the features of testicular seminoma?
Normal AFP
HCG/LDH elevated in 10-20%
Advanced disease 5- year 73%
Sheet like lobular patterns of cells with fibrous component and septa.
What are the features of testicular NSGT?
Younger (20-30)
Worse prognosis
May need retroperitoneal lymph nod dissection
AFP raised in 70%
40% HCG
Heterogenous texture
What drug can characteristically cause epididymitis?
Amiodarone
What is the peak incidence of testicular torsion?
13-15 years
What is the most common cause of acute epidiymo-orchitis?
Chlamydia
What are indications for commencement of dialysis?
Intractable hyperkalaemia
Acidosis
Uraemia symptoms (nausea, pruritus, malaise)
Therapy resistant fluid overload
CKD 5
What are the borders of the anterior triangle of the neck?
Anterior border of SCM
Lower border of Mandible
Anterior midline
What sub triangles are contained within the anterior triangle?
Digastric Triangle (Submandibular gland/nodes, facial vessels, IX)
Muscular triangle (Straps, EJV)
Carotid Triangle (carotid sheath, ansa cervicali)
What is the blood supply of the parathyroids?
Inferior thyroid artery, inserting medially
What is the blood supply to the thyroid?
-Arterial
Superior thyroid artery - 1st branch from external carotid artery (Superior Laryngeal Nerve)
Inferior thyroid artery - thyrocervical trunk (RLN)
-Venous
Superior thyroid vein - IJV
Middle thyroid vein - IJV
Inferior thyroid vein - brachiocephalics
How does parasympathetic and sympathetic stimulation affect the parotid gland?
Para - water saliva
Symp - enzymatic
What muscles are controlled by Trochlear and Abducens CNs?
SO 4 LR 6
Which is the largest cranial nerve?
Trigeminal
- ophthalmic
- maxillary
- mandibular (sensory/motor)
What nerves supply taste to the tongue?
Anterior 2/3 - Facial
Posterior 1/3 - Glossopharyngeal
What are the borders of the posterior triangle of the neck?
Anterior - post SCM
Posterior - anterior Trap
Base - middle 1/3 of clavicle
What are the contents of the posterior triangle of the neck?
-Nerves
Accessory nerve
Phrenic nerve
Three trunks of brachial plexus
- Vessels
EJV
SCA
-Muscles
Inferior belly of omohyoid
Scalene
Which embryological structures does the vagus supply?
4th/6th pharyngeal arches (fore/midgut sections of embryonic gut tube)
What is the lymphatic drainage of the tongue?
Anterior 2/3 ipsilateral submental –> deep cervical
Posterior 1/3 bilateral submandibular –> deepcervical
From which structures are the coverings of the spermatic cord formed?
Internal spermatic fascia –> Transversalis
Cremastic fascia –> IO
External spermatic fascia –> EOA
What are the contents of the spermatic cord?
Three vessels
- Testicular artery
- cremasteric artery
- artery to vas
Three other
- vas deferens
- pampiniform plexus
- lymphatics
Three nerves
- genital branch of genitofemoral
- sympathetic
- ilioinguinal (on outside)
What are the four parts of the male urethra?
Pre-prostatic
Prostatic
Membranous (narrowest, external sphincter)
Penile (longest)
Transitional urothelium –> squamous distally
What are the histological findings for anaplastic thyroid carcinoma?
Rhabdoid cells, multi nucleation, nuclear pleomorphism
what is the most common pancreatic tumour in MEN1?
Gastrinoma > Insulinoma
On which bones is a DXA scan performed?
Radius
Upper Lumbar spine
Lower Lumbar spine
Hip
What can increase 5 HIAA levels?
-Food
Avocados
Bananas
Kiwi
Plantains
Tomatoes
-Medicines
Paracetamol
What can decrease 5HIAA levels?
Heparin
MAOIs
Aspirin
What is the agent of choice for metastatic medullary thyroid cancer?
Vandetanib (TKI) also cabozantinib
How should patients with adrenal cancer be followed up?
3 monthly CT for 2 years
What adjuvant treatment should be considered for adrenal cancers?
Mitotane if Ki67>10%
+ Radiotherapy if Stage 3/R1
In thyroidectomy, what factors increases the risk of postoperative hypocalcaemia?
Central node dissection (20–>35%)
What is the result of a low dose dexamethasone suppression test in Cushings?
Lack of suppression of cortisol
How are the results of the high dose dexamethasone suppression test interpreted?
If suppresses
- Pituitary tumur (CD)
If not then:
-Ectopic ACTH
-Adrenal adenoma
What is the most common presentation of hyperparathyroidism?
Fatigue (>stones/asymptomatic)
What happens to potassium with Cushings?
Hypokalaemia - weak mineralocorticoid effect
What is the most common cause of Cushings after steroids?
Pituitary adenoma
How frequently is a serum calcium of <2.1 on POD 1 seen after thyroidectomy?
25%
When should a paediatric hydrocele be fixed?
IF not going by 2-3 years
How should Thy1 results be managed?
Repeat FNAC, usually after 3 months to allow inflammation to settle
With a normal calcium on POD 1 after thyroidectomy, what supplemental calcium is required?
None
How should patients be prepared for radio iodine remnant ablation post thyroidectomy?
Suppression of TSH, so:
-Levothyroxine (e.g. 100mcg OD) then stop 4 weeks prior
-Liothyronine (e.g. 20mcg TDS) then stop 2 weeks prior
-Low iodine diet post stopping
-Could have levo followed by Lio if timings work
-Could continue Levo then give recombinant TSH at 48/24hours prior
How do the parathyroids relate to the RLN?
Superior above and lateral
Inferior below and medial
In which patients after thyroidectomy is hypocalcaemia most common?
Hungry bone syndrome - screen with ALP (also check and replace Vit D)
What is the blood supply to the adrenal?
Superior adrenal artery from inferior phrenic
Middle adrenal artery from aorta
Inferior adrenal artery from renal artery
Right –> IVC
Left –> Renal vein
What preoperative treatment should patients undergoing pituitary surgery receive?
Steroids
What history and examination findings are relevant in patients with adrenal incidentilomas?
Phaeo - anxiety, palpitations, headaches, hypertension
Hyperaldosteronism - hypokalaemia, hypertension
Hypercortisolism - diabetes, weight gain, hypertension
FH - Endocrinopathy (MEN)
Examination - obesity, facial plethora, hirsutism, proximal muscle weakness
How may adrenal incidentalomas be classified?
Functional
Medulla- phaeo
Cortex - adenoma, carcinoma
Non-functional
Metastasis, lipoma, cyst, haematoma
What features are important in a history and examination of thyroid goitre?
History
–Upper airway symptoms (Cough, stridor, SOB, change in voice)
–Dysphagia
–Rapid growth
–History of irradiation
–Thyroid symptoms (heat/cold intolerance, weight loss/gain, insomnia/tiredness)
–FH of MEN
Examination
- Dominant nodule
- Cervical lymphadenopathy
- retrosternal extension
- bruit
- tracheal deviation, signs of SVC/thoracic outlet obstruction
- thyroid eye signs
How Is a thyroid uptake scan helpful in acute thyrotoxicosis?
Uptake bilateral - Graves
Uptake unilateral - toxic nodule/adenoma
No uptake - thyroiditis
Carbimazole for 6 weeks, if urgent need then potassium iodide and propranolol for 7-10 days
What is Ki-67?
Marker of cell proliferation
What is the differential diagnosis of a parotid lump?
Benign
–Pleomorphic adenoma
–Warthin tumour
–Lipoma
–Neuroma
Malignant Primary
– Adenoid cystic
– Adenocarcinoma
– Mucoepidermoid
– SCC
– Acinic cell carcinoma
Malignant Secondary (SCC, Lymphoma)
How is MEN1 hyperparathyroidism characterised?
–Multigland disease, hyperplasia and adenomas.
–Often ectopic and supernumerary
–Subtotal/total + cervical thymectomy
What is the risk of complications after thyroidectomy?
Hypoparathyroidism/hypocalcaemia 20% transient, 4% permanent
RLN damage 5-10% temporary, 2% permanent, 0.5% bilateral
((can treat with injection of vocal cords with autologous fat))
Superior laryngeal N. 0.5%
Haemorrhage –> theatre 1-2%
How is recurrent Medullary Thyroid cancer managed?
Surgery if feasible
Chemotherapy and radiotherapy can be used but less effective
Tyrosine Kinase inhibitors e.g. Cabozantinib and Vandetinib now licensed
How is recurrent differentiated Thyroid cancer managed?
Papillary or follicular
Surgery if feasible
Chemotherapy or radio-iodine
Can use Lenvatinib (VEGFR)/ sorafenib, then cabozantinib
What are the complications of adrenalectomy?
Overall about 10%
Mortality <0.5%
Major haemorrhage requiring transfusion 5%
Damage to viscera - pancreas, liver, kidneys, diaphragm 2%
Addisonian crisis <1%
What are the subdivisions of the anterior triangle of the neck?
Muscular
Carotid
(posterior belly of digastric)
Submandibular
Submental
What are the boundaries of level 6 neck nodes?
Inf- manubrium
Sup - hyoid
Ant - platysma
Post - prevertebral fascia/trachea
What are branchial cleft cysts?
Anomalies arising from 1-4th branchial clefts
Most common is 2nd (anteromedial to superior SCM), may be associated with IX and XII
1 - Parotid area, 3-middle SCM, 4 lower SCM
Present as cysts, sinuses or fistulae
Do USS +/- CT
Excise (infection, malignancy), can do blue dye or fistula probes
What is the mechanism of carbimazole and how can it cause agranulocytosis?
Thyroid peroxidase inhibition (iodination of tyrosine residues in thyroglobulin)
Causes agranulocytosis via direct toxicity with reactive oxygen species and possibly by immune reactions with ANCA
What are the types of nerve injury?
Sunderland Classification
Grade 1 - neuropraxia
Grade 2 - axontmesis
Grade 3-5 - neurotmesis
How should you examine a neck?
–Inspection
General – scars, cachexia, dyspnoea/stridor/hoarseness/exophthalmos
Neck Lump – anterior/posterior triangle, movement on swallowing or tongue protrusion
–Assessment of lump
Site, size, shape, consistency, mobility/fixity
Pulsatility/bruit, tenderness, transillumination
–Palpate all lymph node basins
–Examine thyroid from behind – general, tongue, swallow
