Pheochromocytoma

Clinical findings of a pheochromocytoma: 6 P's of Pheochromocytoma
Pressure/Paroxysmal bursts
Pounding Pain (headaches)
Perspiration
Pallor
Panic
Palpitations

Rule of 10's:
10% familial (Men 2a, 2b syndromes)
10% bilateral
10% malignant
10% calcify
10% located outside the medulla (a common site is the bladder. If patient gets episodic hypertension with urination, think about this possibility)

Look for urinary VMA (breakdown of NE) and plasma catecholamines!

Oncology2

Knowing where some cancers metastasize, and what metastases go to which organs, can be important. So I've got a few mnemonics and trends to help me memorize these places and organs associated.

First off, notice that Lung and Breast cancers are involved in all these metastases. They are, in fact, the top cancers. (Lung is the top killer, but breast is the top incidence in women)

Metastasis to the brain:

First Aid uses "Lots of Bad Stuff Kills Glia," but I like using "Cancer: Some Love Killing Brain Glia" ...I don't know why, but I can remember that one better.

Lungs

Breast

Skin

Kidney

GI

Metastasis to the liver:

GI related cancers + your most common cancers (lung and breast). Makes sense with the portal system and all.

Cancer Sometimes Penetrates Benign Liver, most common to least common:

Colon > Stomach > Pancreas > Breast > Lung

*Note that Dr. Goljan (amazing pathologist extraordinaire) says that Lung cancer is the most common, more than all the others. Take that info the way you like. I think I'm gonna go with colon cancer as more likely to metastasize to the liver through the portal circulation, it just makes sense (sorry Dr. Goljan)

Metastasis to the bone:

-Make an association with GU cancers, which are able to access the vertebral column through the batson paravertebral venous plexus. The vertebral column is the most common site of bone metastasis.

P.T. Barnum Loves Kids.

Prostate

Testes

Breasts

Lungs

Kidney

Metastasis to the lungs:

"Real Hardcore Cancers Fill Both My Lungs" (I like to read it HardCore cancers, to remind me the "core" is "choriocarcinomas)

Renal Cell Carcinoma

Hepatocellular Carcinoma (which, btw, is also known as a Hepatoma)

Choriocarcinoma

Follicular Thyroid Carcinoma

Breast

Melanoma

Metastasis FROM the liver

Loves the Adrenals. Also your common ones that receive metastasis get their revenge on the lungs: Breast, Brain, Liver.

Metastasis to the heart

You don't often think about the heart, so I thought I'd just say that Melanoma loves the heart. You also get a lot of Lymphomas metastasizing to the heart. And your two commons: Lung and Breast. Note that metastasis is more common than primary heart cancer.

Whew, that's a lot of mnemonics. Hope you enjoy!

Oncology1

Cancer's a pretty huge subject on the USMLE! I wish I had a mnemonic for all the different tumor suppressors, oncogenes, tumor markers, metastases, cancer associated syndromes, and what not, because they can be so hard to flat out memorize. However, I DO have a few tricks that I've found to be useful, that you may find useful, too.

Keep in mind this is not as high yield as most topics. I'd get a general feel, but to be honest, knowing what chromosome the tumor suppressor genes are on is very low yield. I'm not sure why I memorized it. But I did, so I thought I'd share how I did. If you're just starting on oncology, I'd actually look at oncology2 first. In fact, maybe don't even worry about oncology1. It's my OCD showing through.

Oncogenes


Okay, so you've probably memorized that erb-B2/HER2/Neu is related to breast and ovarian cancer. But did you know that the gene product is a tyrosine kinase? I've seen some questions that actually test on this fact. Now, it may not be worth your time, but if you're wanting to score extraordinarily high, it probably is. Anything extra thing you can know adds fuel to your arsenal against these step 1 questions. So without further adieu, here are some mnemonics and trends I've noticed for oncogenes.

"Able, Tyred (tired) Erb Retired." (I like to read it 'although still able, Erb retired because he was tired')

Tyrosine Kinases:
Abl - CML
Erb-B2 - breast, ovarian
Ret- MEN 2A, 2B

Myc:
all of these are transcription factors. Sorry, just a trend, no good mnemonic.
L-myc: Lungs
N-myc: Neuroblastoma
c-myc: Burkitt's (duh, you've got this one memorized by now. Don't forget t(8, 14)!)

Anti-Apoptosis
bcl-2: follicular lymphoma. Again, you've probably already memorized this, the two are like lamb and tuna fish (or maybe spaghetti and meatballs? Perhaps that's a better analogy?)

c-kit: cytokine receptor. Note also it's a tyrosine kinase receptor.

GTPase:
Ras: colon carcinoma. No good mnemonic for this. Sorry... but you should remember the the Ras is a GTPase involved in signal transduction from biochem. Or maybe it's just me that remembers that. Mmmm mmmmm biochem is AWEsome. Maybe you can think Ras --- GTPase? Now I'm stretching.

Tumor Suppressor Genes (TSG)


No great mnemonic for all of them, and for some reason I made a mnemonic relating to the chromosome that they're on. I had a qbank question that I think scarred (and scared) me into memorizing the chromosomes/tumor suppressor gene associations. This may not be worth your time.

p53: 17p. Note that the TSG's that begin with p will be on the p arm (short arm) of the chromosome. All the rest of the TSG's are on the q arm, except WT1 and VHL (ah, exceptions). Also note, 53 + 17 is a nice round number, 70. Works for me (sorry, some of my math tricks are lame. But when you have to flat out memorize numbers, I guess relating numbers to math is a way that helps).
-Another mnemonic for this to relate it to LI-Fraumeni: Take the LI and rotate it 180 degrees and you should have: 17.

RB: associated with bilateral retinoblastoma and osteosarcomas. On chromosome 13 (break down the initials RB, and highlight the left side of the R and the right side of the B. You get the number 13. Write RB on a piece of paper and you'll see what I mean).

VHL: VHL, 3 letters, 3rd chromosome. (and don't forget, on p arm!)

BRCA1, BRCA2: I just related these to the 2 main TSG's, p53 and Rb, which are 17 and 13. Alphabetically, p53 and Rb are in order, just like BRCA1 and BRCA2. So, BRCA1 is 17, and BRCA2 is 13. Another OCD mnemonic for you.

NF1: again, a lot of these important TSG's seem to be on chromosome 17, as is NF1. Maybe you can make the link that NF1 and BRCA1 are both on 17.
NF2: Take the 2, make 22. Chromosome 22.

p16: 9p. Again, it's on the p arm because it begins with p. And again, we want to add up to a nice number: 16 + 9 = 15. I don't know, multiples of 5 and 10 are just nicer, I guess. Somehow, remember this has to do with Melanoma.

DPC: Deleted in Pancreatic Cancer.
DCC: Deleted in Colon Cancer.
Both of these TSG's are on chromosome 18. Can't think of a good way to make this association.

APC: associated with FAP. Think polyp. 5 letters. Chromosome 5.

WT1: Just like we did for NF2, we take the 1, and make 11. Just write it twice. Also, it's easy to remember this is Wilm's Tumor, right? And RCC (that's also from the kidney, easy association). It's on the p arm!
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And that's it! Hope that benefits somebody.

Psammoma bodies

Here's a good mnemonic to figure out which cancers have psammoma bodies (concentric, laminated, calcified spheres):

PPSSaMMoma

Papillary carcinoma of the thyroid (and, if you want more detail, papillary renal cell carcinoma)

Prolactinoma

Serous cystadenocarcinoma of the ovary

Somatostatinoma

Meningioma

Mesothelioma

The somatostatinoma, prolactinoma, and RCC are not as high yield. So you'd be safe with the mneomnic "PSaMMoma"

Wiskott-Aldrich and CGD

Wiskott-Aldrich Syndrome

Think "WAX TIE"

WA: Wiskott-Aldritch

X: X-linked Recessive

T: Thrombocytopenia

I: Infections

E: Eczema

Also, this helps with the immunoglobulins present:

WAX TIE... decreased IgM (think of the W as an upside down M, suggesting a decreased IgM), Increased IgA, Increased IgE

Chronic Granulomatous Disease

I don't have much to say about this, it's lack of NADPH oxidase, leading to increased infections to microbes that have catalase. So what are the catalase organisms? There are questions that are tricky, giving you names of organisms that you don't normally think about. Really, nocardia, aspergillus, and pseudomonas capecia are high yield (since they usually won't give you Staph aureus). So for the catalase positive organisms, remember this:

SNAPE

Staph aureus

Nocardia

Aspergillus

Pseudomonas (capeciae)

E. coli... or generally, Enterobactericiae

Check out my mnemonic on Enterobactericiae if you want to go even more detailed.

Microbiology part2

Just some more random mnemonics of microbiology:

Obligate Aerobes: Nagging Pests Must Breathe
Nocardia
Pseudomonas
Mycobacterium
Bacillus

Anaerobes: Can't Breathe Air (aka your ABC's of anaerobic bacteria)
Clostridia
Bacteroides
Actinomyces

5 bacterial produces transferred by phages: ABCDE
ShigA-like toxin (this is aka Verotoxin)
Botulinum toxin
Cholera toxin
Diphtheria toxin
Erythrogenic toxin (Strep pyogenes)

This last one's not my favorite of mnemonics... especially with that "A" being shigA toxin... but what can you do. Note that Staph aureus' bacterial resistance is also conferred through a phage!

Microbiology part 1

To remember the relevant medical microbial producers of urease, remember:

"Urease PUNCH"

Proteus mirabilis
Ureaplasma urealyticum
Nocardia asteroides
Cryptococcus neoformans
Helicobacter pylori

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Actinomyces israelii vs Nocardia asteroides- both are gram +, and form long, branching hyphae, which is characteristic.

So what differentiates them? Actinomyces is anaerobic, colonizes mouth and vagina normally, and causes abscesses that drain with sulfur granules.  Nocardia is aerobic, lives in water and soil, and causes cutaneous (through trauma), respiratory, or disseminated (e.g. brain/meningeal, kidney) involvement. Only the cutaneous problems are seen in immunocompetent people.

Treatments: SNAP

SMX/TMP - Nocardia
Actinomyces - Penicillin G

Actinomyces israelii: There is a lot of sand in Israel. The yellow sulfur granules look like sand.

Nocardia asteroides: Asteroids are foreign to Earth, just like this bacteria is foreign to the human body (not grown in normal flora)