28 Quick Hits 1 - Final Edit

Ladies and gentlemen, welcome back to Behind the Knives Abcite Review. We are thrilled to have you. Hopefully, you're still listening and haven't gotten too annoyed of us. We have a rapid fire review for you today. I'm here with our prolific surgical education fellows, Nina Clark and Dan Sheese. Seriously, we love them.

If you love surgical education too, you should think about joining our team. We are going to do a rapid fire review. So we're going to rip through some topics and we're going to think about keywords and associations things that are going to help you get that question right on the ab site. So we're going to start with Nina and we're going to start with breast.

There are five key nerves that we think about when it comes to breast surgery. What are those nerves and what happens when you injure those nerves? Yeah, Patrick. So the most commonly injured nerve in breast surgery is the intercostal brachiocutaneous nerve. So this is the one that's going to impact your inner arm sensation, and that's what you're going to look for in your post operative visit with those patients.

Next up, you've got the long thoracic nerve.

This is more medial in the axilla and innervates the serratus anterior, which can result in that classic winged scapula picture that you're going to see on ab site. Next up, a little bit more dorsal to that is the thoracodorsal nerve. This innervates the latissimus dorsi, and injury to this nerve results in weak adduction and internal rotation of the ipsilateral arm.

The last two are less commonly thought of when you think about breast surgery and these classic nerve injuries, but they can show up on abscesses. And those are the medial pectoral nerve, which innervates both the pec major and the pec minor, and actually lies more lateral on the chest wall, which is a little bit confusing because the lateral pectoral nerve only innervates the pec major and actually lies more medial.

That's a perfect abstract question, isn't it? Well, all right, that's in plexus. What is it? That's in plexus. That's the valvulous vein plexus that allows direct hematogenous spread of breast cancer to the spine. So if you see somebody with spine mets, that's usually how it got there. Yeah. How about you describe different nipple discharge and their

association with disease?

Oh, yes. Always a fun one and kind of terrifying to think about. So green discharge typically is in the context of fibrocystic changes and that can often show up as that more physiologic discharge. So think about bilateral multiple ducts, that kind of thing. Bloody discharge is more concerning in general.

Most commonly, it shows up in the context of an introductal papilloma, which is not premalignant, but still generally warrants a resection. Serous discharge can raise concern for malignant causes as well, especially if it's spontaneous. And in general, when you're thinking about discharge, get breast imaging, check a prolactin level, do the normal workup for breast masses.

But this can be in the context of non malignant causes. Unilateral discharge should always prompt breast imaging because this is more often in the context of a malignant or a premalignant diagnosis. Any breast imaging, if you find something that looks abnormal, biopsy it and get a full workup. When you think about this breast discharge, you'll sometimes see duct excisions or terminal duct excisions.

That's really a last resort that you'll go to if every other imaging workup that you've done so far is negative and you're still concerned about discharge. Fantastic. So, L. C. I. S. This is usually a marker for increased risk of cancer in either breast, actually, regardless of where you find it. So what are some other key points for lobular carcinoma inside to L.

C. I. S. Is this marker for risk of cancer? That's how I think about it. It's not pre malignant in and of itself. There's typically no imaging findings with L. C. I. S. Which I think is a little tricky. It's often just found incidentally when somebody is getting a biopsy or imaging for something else. And in general, you should do an excisional biopsy for a patient with a diagnosis of LCIS.

But the nice thing about this is because it's more a risk factor for cancer, you generally don't have to re excise even if you end up with positive margins after doing an excisional biopsy for LCIS. So you do not generally have to re excise for a positive margin. The only exception to that rule is pleomorphic subtype of LCIS, which we treat more like DCIS, which we'll talk about, I think, next.

And we would re excise if you have a positive margin. So pleomorphic LCIS treated as a pre malignant lesion, the rest you can generally leave, even if you have a positive margin. Okay. So how about DCIS? And what are some of the key findings and things we need to worry about there? Yeah. So DCIS is the classic, more of a pre malignant finding.

And so it's therefore treated more aggressively. So for these cases, you're doing a formal oncologic resection of the primary tumor. And DCIS has a two millimeter margin that you want to get on that lumpectomy. If you do a breast conserving therapy with a lumpectomy, you do follow that up with radiation therapy, postoperatively, just like you do with an invasive cancer.

If you do a breast conserving surgery with DCIS, you do not generally have to do a sentinel node biopsy. Again, because DCIS is premalignant. It's not invasive. However, if a patient is receiving a simple mastectomy or mastectomy for DCIS, then you do your sentinel node because you are basically getting rid of all the breast tissue that you would otherwise use to

get a sentinel node.

And if your pathology comes back as malignant, in that case, you've kind of screwed the pooch and you can't get that sentinel node biopsy after the fact. Postoperatively, patients with DCIS should also get adjuvant endocrine therapy if their tumors are ERPR positive. That's a fantastic summary. So L. C. I.

S. You don't necessarily need those negative margins unless it's a pleomorphic subtype. D. C. I. S. two millimeter margins. And you really talked about the overall treatment strategy very clearly. So thank you for that. I promise everyone listening. The rest of this is not as hard as the breast. We're starting off with the good stuff.

So Nina going on with another really complicated question. But really, we're talking about just the beginning of the workup for an individual with a breast lump. Yeah. And we want to cut that into folks with who are less than 30 years old and patients who are greater than 30 years old. What are some of the key thoughts there in terms of the approach?

Yep. Younger patients have dense breasts. So generally your first line imaging study in those patients is an ultrasound. You can also consider an MRI and most of these patients should also get a

mammogram just to see if it is showing up on mammogram if there's a palpable mass. If a patient over 30 years old has a palpable mass, get a mammogram as your standard of care and then augment that with an ultrasound.

Fantastic. What are the breast cancer screening recs now for the average risk patient? There's multiple, correct? There are so many and generally they all kind of change on a yearly basis. So this is definitely something I always have to look up right before abcite just to make sure I'm kind of on the right track.

So there's probably no exact cutoff and most of these questions won't ask you directly, like, right on the cusp of where some of these changing recommendations have been. But the American College of Surgeons recommends that you start annual mammograms at age 40. So most of these will start with annual mammograms or every two year mammograms around the ages of 40 to 45.

And you can use that as your general go to. Fantastic. So there's level one, two, and three lymph nodes. When we talk about breast and breast surgery where are those

located? Yeah, so level one is lateral to the pec minor. Level two is beneath the pec minor and level three is medial to the pec minor.

The standard for a modified radical mastectomy only removes levels one and two. Only level three gets removed if it's clinically positive. So if you're in the operating room and you see a positive node, but otherwise you leave it alone. All right, where does breast cancer most commonly metastasize to is the bone Patrick.

All right, so we have a we're thinking about hormone therapy And what's the difference between premenopausal and postmenopausal patients? What type of drug classes or specific drugs do we need to know? Yes, so this has been studied in a couple of randomized trials pre menopausal patients should generally be treated with a CIRM, which is the tamoxifens or the raloxifene, and these medications are associated with an increased risk of endometrial cancer and venous thromboembolic events.

Post menopausal patients, on the other hand, should get those aromatase inhibitors, and that's your anastrozole and your letrozole. Those are

associated with osteoporosis, which you should generally be watching for anyway in this population. Yeah, I feel like that's a good question, right? The serums associated with endometrial cancer and VTE.

I've seen that numerous times. So, what is the treatment for invasive carcinoma when it comes to the neoadjuvant aspect of care? This is something I, again, have to review almost every single year is who gets neoadjuvant treatment for breast cancer. So, these are going to be the patients who have an inoperable primary with distant metastasis.

locally advanced disease. So it's stage three with lymph node involvement or really bulky primary patients with inflammatory breast cancer all get neoadjuvant treatment, a large tumor that with a patient who wants breast conserving therapy. So the idea of being there being that you want to shrink that tumor so that they can become a candidate for lumpectomy and patients with early stage triple negative breast cancer all generally will be shunted towards getting neoadjuvant therapy.

And this generally involves chemotherapy as well as endocrine therapy if the tumor's

ERP are positive and trastuzumab or Herceptin if it's HER2 positive. So what's the rundown of some basic or the surgical approaches for primary tumors and breast cancer? Again, kind of a big picture view. Yes, I love this question because I feel like this is one of the very few things that is kind of simple about breast cancer.

But you basically have two options at all times. You have a breast conserving therapy, which is a lump, lumpectomy that always goes along with post op radiation and except for very, very few circumstances. So Post op radiation, just think of it as a must if you're doing a lumpectomy. The confusing part there, I guess, is that the margins for an invasive breast cancer is no tumor on ink as opposed to DACIS, which remember that was a two millimeter margin.

So for invasive cancer, you just don't want tumor on your ink. The other option for patients with primary breast cancer is mastectomy, which only needs radiation if the tumor was extremely large, or if there are other complicating factors. How about taking a stab at lymph nodes when it comes to breast cancer?

So there's gonna be a mouthful, and I think we have it nicely summarized

here. So why don't you go through it for everyone? Yeah, so this is where the surgery for breast cancer gets complicated. Generally, in patients who are clinically node negative, which means they have nothing on their exam or on any ultrasounds that you've gotten, they get a sentinel lymph node biopsy.

The way you manage that is this ACOGZ11 and the AMARUS trial that you've heard of 8 million times here at residency. So, if a patient has a sentinel node biopsy, one to two of their nodes come back positive and they have an early stage T1 or T2 primary and they got a lumpectomy, then you're all good.

You can just do radiation like you would anyway for breast cancer therapy and the patient does not require any additional axillary surgery. If they have one or two positive lymph nodes on a central node biopsy and they got a mastectomy, you also can generally do radiation therapy. This is at a MAROS trial and there don't need any additional axillary surgery.

If a patient, however, has three or more positive nodes or a very large primary, or for whatever reason they can't get radiation after surgery, then you would

proceed with an axillary lymph node dissection. In a patient who's clinically node positive, then you think getting neoadjuvant therapy on board early.

After neoadjuvant, if they've converted to becoming clinically node negative, and if they had early stage disease prior to getting neoadjuvant, so not like huge bulky metastasis in their nodes, then you can consider doing a sentinel node biopsy when they eventually get to the operating room. But if they're still clinically persistently positive nodes after neoadjuvant therapy.

Or if they had a ton of notes that were positive prior to getting their surgery and prior to getting their neoadjuvant, you would do an axillary node dissection in those cases, right? So I think the most common question that would come up on the test is for a patient who's clinically node negative, you do a sentinel lymph node biopsy and they're going to give you some results.

And if they have one to two nodes positive and they have a small tumor, Then you're good with your lumpectomy if they have one or two positive and they did a mastectomy. You're also looking at radiation therapy for those patients. If there are three or more

nodes positive, or there's a really large primary tumor, then you're thinking axillary lymph node dissection.

I think I got that correct. I think you did too. Okay. So let's move on to adjuvant therapy. So what kind of adjuvant therapy are out there and options for our breast cancer patients? So this falls into four categories in my mind, chemo, radiation, hormone therapy, and anti HER2 therapy.

Chemotherapy, generally if a patient has positive nodes or a greater than one centimeter primary, unless they're really low risk and hormone receptor positive, they're going to get chemotherapy after surgery. Radiation, again, this is always going to go alongside breast conserving therapy. So if you see somebody with a lumpectomy, give them radiation after surgery.

After a mastectomy, patients still might need radiation if they had a lot of nodal disease, or if they had nodal disease that you weren't able to surgically address. So those are like the internal mammary nodal metastases that you might see sometimes. Anybody with skin or chest wall involvement, a positive margin, or inflammatory breast cancer should also

get post op radiation therapy.

Hormone therapy, generally think about this for anybody who has those ERP or positivity on their tumors, even if it's DCIS. This generally works as a 5 10 year treatment course with either the CIRM or AI, depending on their age group. And then finally, the anti HER2 therapy is directed therapy for patients who have HER2 positive tumors, and it generally is used for a year after surgery.

All right. Fantastic. Again, we're getting the hard stuff out of the way. All right. What is Stu Trev's syndrome or Trev's syndrome. I like that you wrote Stewie Trev's, but I did comment on the side and said it's Stuart Trev's. And this is a lymphangiosarcoma of the upper extremity that happens after an axillary lymph node dissection.

So this is where you're going to look for a patient who comes into clinic postoperatively with a spreading or kind of bruise like looking lesion or a raised purplish reddish lesion on their skin on their arm. Excellent. Can you describe the BI RADS classification system?

Yes, also highly testable. So a BI RADS 0 is non diagnostic.

You need another type of imaging, so either a diagnostic mammogram or an ultrasound. BI RADS 1 is the normal mammogram, so you go right back to your normal screening. BI RADS 2 is a benign finding on a mammogram, so this also goes back to normal screening. BI RADS 3 is probably benign, these are patients where you're going to coordinate short interval follow up, generally in about six months with another mammogram.

BI RADS 4 is a suspicious finding, that's, you're going to get a biopsy for that. BI RADS 5 is highly suspicious and is also going to get a biopsy. And BI RADS 6 is for those tricky ones where you already know that they have a malignancy, it's biopsy proven and you're just re imaging it. Great. When it comes to lymph node staging, what's unique about pregnant patients?

Yes this is also often on abcite. So you can use your technetium radioactive injectable for your sentinel lymph node biopsy in pregnant patients. However, do not use blue dye. So avoid

methylene blue in any pregnant patient. Alright, we did it. Deep breath. Dan, you are up. Painful. Let's move on to abdominal wall.

Alright, you have a hernia between the lat, the external oblique, and the iliac crest. What is the name? This is a petite hernia. Okay, a hernia just lateral to the rectus, usually below the argument line. This is your spaghillion hernia. Gosh, this is so much easier than Nina's section. You have a little piece of bowel, but not the whole thing, stuck in a hernia.

And it happens to be the anti mesenteric side of that bowel. This is the Richter's hernia. You're right. And the incarcerated Meck Meckle's hernia. I would love to see this. The Latre's hernia. Okay. And last, the upper lumbar hernia that borders the 12th rib, the erector spinae muscles, and the posterior border of the inferior oblique.

This is Grinfeld's hernia. Okay, now this is a really hard one. The most common solid of mental tumor? That's a metastasis. Alright, Nina, you're back up. Let's hit up that endocrine. We're coming back for you, Dan. I hate this. Alright, there are three types of

congenital adrenal hyperplasia, or CAH, that we need to know.

The first is 21 hydroxylase deficiency. What do you see with that, Nina? So this is the most common that we see. And in these patients, you'll have salt wasting, hypotension, and precocious puberty in males. And then in females, you'll have virilization. Okay. What about deficiency in 11 beta hydroxylase?

So this one's the not salt wasting. So you've got a precocious puberty in males and virilization in females without any of the sodium issues. Right. And then last is 17 alpha hydroxylase deficiency. Yep. So this one's also not sodium wasting but these patients will have ambiguous male genitalia. I like to remember this with the ones being arrows.

So I make a chart with the first column being A for aldosterone and the second column being T for testosterone. And then for each one, you just draw a little, like, two and then an up arrow. And so for 21, you have... normal aldosterone and then high testosterone. For example, for 11,

they're both high. And for 17, the a column.

So your aldosterone is high and your T is not. Okay. So we got arrows, arrows for the ones. Yep. So Cushing syndrome, you're almost certain to get a question about this on the test. How do we start that workup? How do we verify hypercortisol in these patients? Yeah, I'm realizing with this one that I really made myself do a lot of painful work, whereas Dan got to just answer a bunch of herniatypes.

To work up somebody with suspected Cushing syndrome, you first want to verify that they actually have hypercortisolism. So you're going to get a 24 hour urine cortisol. You'd expect that to be three times the upper limit of normal or higher. You also can get a late night salivary cortisol. If those are inconclusive, you can use your low dose.

Dex suppression test and you would still see am levels of cortisol after giving dexamethasone, those would still be high. Then you want to localize. Is it an adrenal source or an extra adrenal source of all this extra cortisol floating around? So that's where you're going to get your serum. ACTH, if it's working correctly,

ACTH should work to decrease cortisol production from an adrenal gland.

So if your ACTH is low, you're looking at an adrenal source of cortisol. If your ACTH remains high, then you start looking for things like ectopic sources or pituitary adenomas. The third step is you have to localize your extragenal source of all this extra cortisol. So you're going to perform a high dose dexamethasone suppression test.

In the case of a pituitary source, you're going to see suppression. However, an ectopic source will not be suppressed with a high dose dex suppression test. And so there's something that's gone completely rogue, usually a lung tumor in that case. Fantastic. So first we're going to verify hyper cortisolism.

The most common ways are the 24 hour urine cortisol, which would be three times upper limit of normal. This is inconclusive. We can try the low dose dexamethasone suppression test. We then want to localize this lesion, whether to figure out whether it's adrenal or extra adrenal. We do this with serum ACTH.

And if we think it's extra adrenal, we can farther localize with a high dose

dexamethasone. Suppression test. We can also throw an MRI to the head when we're thinking pituitary and then CT scans of the chest. If we're trying to find that mass in the lungs that is acting as our topic source. So what is the number one cause of cushions?

The number one cause is actually iotogenic, followed after by pituitary adenomas, which is that classic Cushing's disease and third being adrenal adenomas. Right push, uh uh, pituitary adenoma is called C'S disease, which can get confusing. So what two drugs inhibit steroid formation, that would be ketoconazole and reone.

What is the wolf ticoff effect? This is when you give somebody luol solution or potassium iodide, and it ends up causing this paradoxical inhibition of TS h's. Action On the thyroid gland, I got a question stem with a 47 year old patient. They have metastatic papillary thyroid cancer, and I need to know what the stage is.

That's an easy one. And this is one of my favorite questions to show up on app site. This is a stage two disease.

Remember that for differentiated thyroid cancers, patients under 55 can only be two things. Stage one with no meds or stage two with meds. It's more complex in older patients, but usually they're trying to get at that when they ask you this question.

Boom. Love it. What is the most common type of thyroid cancer and how would you go about treating it? Yeah, so that's going to be your papillary thyroid cancer, which is makes up about 80 to 90 percent of your thyroid cancers. Overall, if it's a small tumor, so being under a centimeter and it's low risk pathology, then those patients might be able to get a thyroid lobectomy.

However, if it's larger than a centimeter bilateral tumor multi centric tumor or if there's any concern for positive margins or other high risk factors like a history of neck radiation, then you're going to perform a total thyroidectomy. If you have clinically positive nodes, or any extra thyroidal involvement, then you proceed with a neck dissection, and the way that you determine what type you're going to do is based on where those nodes are.

If only central neck nodes are positive, then you just have to do a central neck

dissection. However, if a lateral node is positive, you assume that it got there via the central neck, so you do both a lateral and a central neck dissection in that case. If you've got metastasis, residual disease any positive lymph nodes, capsular invasion, et cetera.

Those are the patients you're going to think about radioactive iodine, which you're going to give about six weeks after surgery, this is much easier to do if you took out the whole thyroid gland, which is part of the rationale for why those higher risk or larger primary tumors tend to get a total thyroid ectomy.

Nina, remind me, what's the protein we can follow when it comes to a monitoring for thyroid cancer recurrence? You're going to watch for your thyroid globulin levels. Right, that's after a total thyroidectomy. Alright, if I say medullary thyroid cancer, you say? MEN2. This is the parafollicular C cells that secrete calcitonin, and so that's your tumor marker for that type of cancer.

And the treatment for medullary thyroid is always pretty aggressive. I think of just doing everything you can. So you do a total thyroidectomy and a central neck dissection by default.

Right. Remind me what MEN1 consists of. This one's my favorite. Hit a pair of pink. So pituitary adenomas. With prolactinomas being most common, parathyroid hyperplasias and pancreatic tumors.

Most commonly a gastro. All right, how about two A? Two A is parathyroid, medullary, thyroid carcinoma, and pheochromocytomas. All right. And two B, the kind of wonky one. So this one also has medullary, thyroid carcinoma, and pheochromocytoma, but you also get those mucosal neuromas and the maren habitus. How about the blood supply to all four parathyroid glands?

As you wrote in your slide here, all four of the little bastards are served by the inferior thyroid artery. Yeah, they are little bastards. I hope to never see them again. That's true. What does PTH do and what does vitamin D do? So PTH serves to increase calcium and decrease phosphate, so it increases your osteoclast activity, increases renal uptake of calcium, decreases renal uptake of phosphate, and increases vitamin D

activity.

Vitamin D helps us to absorb calcium, so it increases calcium in general and increases phosphate. Alright, primary hyperparathyroidism. Primary is the easiest one to remember. This is your parathyroid adenoma. It's like autonomously making too much PTH. Right. Versus secondary? Secondary is going to be a patient in renal failure.

So your kidneys are really bad at activating vitamin D and you lose calcium as a result of it. And your parathyroids try to make up for it, in my mind at least, by overproducing PTH. Right. And then tertiary? Tertiary is like after a patient has already had secondary type. So you've had renal failure, your parathyroids are used to cranking out PTH all the time, and then all of a sudden, in a single day, you get a new kidney that works, and your parathyroids have like way too much momentum and they forget to stop.

You got a question, Stem, where you can't find the parathyroid gland. Where is it? I thought this was your dream, Patrick, never finding a parathyroid gland again. But

you're going to go looking in the thymus, and really just think about the anatomic places where parathyroid glands can hide. The thymus is most common, so generally you're going to do a cervical thymectomy.

If they don't give you that as an option, also look in the retroesophageal, tracheoesophageal groove, carotid sheath, or embedded in the thyroid. Alright, last question. What is the half life of... PTH, the end is in sight. So PTH has a half-life of 10 minutes. And this is really important because when you're measuring your intraoperative PTH to make sure that you remove the right amount or the right number of parathyroid glands, your dual criteria means that you're gonna have to wait 10 minutes for the PTH level to drop.

So the first of those is it has to drop by 10 minutes by about 50%. And the second criteria is that it has to drop to a level of near normal. Dan, let's talk. All right, put me in a coach. I'm falling asleep on the bench. And what's the normal length of the spleen on ultrasound? So for this, I think of less than 13 centimeters.

So, what are Howell Jolly, Jolly Bodies

and what are Heinz Bodies? What's the difference between the two? So, Howell Jolly Bodies are nuclear remnants and erythrocytes. And usually the way they ask this on ab site is ask you do a splenectomy on a patient and then you still see Howell Jolly Bodies.

On the blood smear, which means that they may have an aberrant spleen or there's still a remnant present. Heinz bodies, you see with a oxidized hemoglobin, and so we see this more thalassemia or G6PD deficiency. So when it comes to ITP what's our treatment? So ITP, we think first line would be steroids followed by IVIG.

If both of these are failing to work, then, then at that point we consider splenectomy. If we're considering splenectomy, we want to try to give the three vaccines prior to surgery, being H flu meningococcal, and pneumococcal vaccines prior. And then post splenectomy, you'll most likely see increased red blood cells, white blood cells, and platelets.

And you want to think about starting aspirin if that platelet count gets over a million. And when do we want

to give those vaccines ideally for an elective splenectomy? So elective, we want to try to do two weeks prior. In the trauma world, we try we'd love to give it two weeks after is an ideal time point but oftentimes we'll give it to patients before they're discharged to ensure they get those splenectomy vaccines.

What's another common indication or relatively common indication for splenectomy when it comes to the hematologic issues? Yeah, so one big one is a hereditary spherocytosis. And in this, we always try to wait until the patient's at least five years old prior to splenectomy. You can think of other more rare things such as elliptocytosis, thalassemias, wiskato aldrich autoimmune hemolytic anemia, TTP, and lymphoma.

All right. That wraps it up for today. We hope you find these little tips and tricks useful. Dan and Nina are outside ACEs. We'll be back with some more high yield reviews in our next episode, dominate the day. So Nina, yours is like insane. When Dan gets all the little baby ones.