Other antithyroid medications

Lugol's iodine (KI)
- short term antithyroid medication
- inhibits thyroglobulin proteolysis (which prevents release of T4/3)
- also prevents organification of thyroid hormone
- effects last 10-14 days

T3 production inhibitors
- major role of beta-blockers is to block the peripheral conversion of T4 to T3
- they do this in addition to treat symptomatic effects of hyperthyroidism.

Radioactive iodine.
- 131I
- trapped by follicular cells incorporated into tyrosine complex and deposited into colloid where beta dray destroys surrounding parenchyma

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Thionamide drugs

Two common antithyroid drugs used in north America
- propothiouracul (PTU)
- methimazole (tapazole)

PTU is preferred in the treatment of thyroid storm because it acts both on the thyroid and also peripherally

- in the thyroid both drugs inhibit TPO which converts iodide to iodine to be incorporated into thyroid hormone.
- PTU also prevents the peripheral conversion of t4 into the more active T3

Both drugs can cause skin rash. Agranulocytosis is rare but occurs with both
- 0.44% PTU
- 0.12% methimazole

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Amyloidosis Diagnosis

Diagnosis is via abdominal fat pad biopsy.
- easier and less morbid than biopsy of affected organ
- fat droplet place on glass slide and smeared to single layer
- sent air dried to lab for congo red staining which will allow pathologist to see amyloid deposits within fat

easiest to do an excisional biopsy of fat
core biopsy of fat also described.

http://www.amyloid.nl/investigations.htm

Pathological Subtypes of Breast Cancer

There are over 12 subtypes of breast cancer - though most of them are rare
- Invasive carcinoma (No Special Type) is by far the most common followed by Invasive lobular
- the remaining subtypes are quite rare

1) Invasive carcinoma: No Special Type
- majority 70-80%
Subtypes:
- Luminal A (ER +ve, HER2/neu -ve)
- Luminal B (Triple +ve)
- Normal Breast-Like (ER +ve, HER2/neu -ve)
- Basal-Like (ER -ve, PR -ve, HER2/neu -ve)
- HER2 positive (ER -ve, HER2/neu +ve; associated with brain mets)

2) Invasive Lobular Carcinoma
- increased bilateral

3) Medullary Carcinoma
- 6th decade of life
- slightly better prognosis than NST carcinomas despite negative histological features
- high nuclear grade, aneuploidy, absence of hormone receptors, high proliferative rate
- rapidly growing with smooth borders and thereforeon imaging can resemble a benign lesion

4) Mucinous (Colloid) Carcinoma
- older women
- grow slowly
- ER +ve, LN mets uncommon
- slightly better prognosis vs. NST

5) Invasive Papillary Carcinoma
- <1% of invasive ca
- ER +ve
- favorable prognosis
- much different outcome compared to micropapillary carcinoma

6) Micropapillary Carcinoma
- ER -ve, HER2/neu _ve
- LN mets
- poor prognosis

7) Metaplastic carcinoma
- rare type of breast cancer (<1% of cases)
- Matrix-producing carcinomas
- Triple negative
- LN mets infrequent but poor prognosis

Source:
Robbins

Neoadjuvant Therapy for Breast Cancer

Standard of care foe bulky breast or axillary disease:
- primary tumor 2-5cm
- <2cm but metastatic axillary LNs

Early skeptisism for this approach is unfounded: concern initially that pts would have poorer operative outcomes due to wound complications

McCready and Colleagues:
- ALN retains prognostic value after neoadjuvant Rx
- Not clear if neoadjuvant Rx impacts survival (but it's at least equivalent overall survival)
- 80% of pts have ~50% shriknage of tumor
- only 2-3% have signs of progression during neoadjuvant Rx

If there is complete pathologic regression there is a survival benefit

NSABP B-18:
- 4 cycles of doxorubicin and cyclophosphamide
- 5 year survival of complete response pts ~50%
- however, only 12% of pts achieve this kind of response

Advantages:
- Down size tumor in 80% of pts
- Determine which are chemo-responsive

Lower Limb 4 Compartment Fasciotomy

Compartments:
- Anterior
- Lateral
- Superficial Posterior
- Deep Posterior

Lateral incision: (Over fibula)
- releases anterior and lateral compartments
- watch out for superficial peroneal nerve which can be in lateral but also anterior compartment near intermuscular septum

Medial incision: (2-3 cm medial to edge of tibia)
- releases superficial and deep posterior compartments
- incise superficial compartment then release soleus muscle from posterior edge of tibia to arrive at deep compartment
- watch for saphenous vein which is superficial and runs at the posterior edge of tibia
- watch out for posterior tibial neurovascular bundle and achilles tendon which runs in superficial posterior compartment

http://www.youtube.com/watch?v=-1NDJkFH1vM&feature=related
http://www.youtube.com/watch?v=6c5r5brMOso

MELD score

MELD = 3.78[Ln serum bilirubin (mg/dL)] + 11.2[Ln INR] + 9.57[Ln serum creatinine (mg/dL)] + 6.43

In interpreting the MELD Score in hospitalized patients, the 3 month mortality is:

• 40 or more — 71.3% mortality
• 30–39 — 52.6% mortality
• 20–29 — 19.6% mortality
• 10–19 — 6.0% mortality
• <9 — 1.9% mortality

Branches of the Internal Iliac Artery

I Love Going Places In My Very Own Underwear:

Ileolumbar
Lateral sacral
Gluteal (superior and inferior)
Pudendal (internal)
Inferior vesicle (uterine in females)
Middle rectal
Vaginal
Obturator
Umbilical

Branches of the Long Saphenous Vein

6 tributaries off the long saphenous at the sapheno-femoral junction.
- important clinically when ligating and stripping the long saphenous for varicose veins
- also need to know and likely ligate when doing a superficial groin LND

2 circumflex femoral veins (medial and lateral)
2 circumflex iliac veins (superficial and deep)
superficial inferior epigastric
external pudendal