POLYCYSTIC OVARIAN SYNDROME
Hyper-LH obesity syndrome
Polycystic Ovarian Syndrome (PCOS) is a particular pattern of sex hormone dysregulation, and it’s the most common endocrine disorder in women. It gets its name from the numerous cysts that appear on the ovaries, but it’s important to know that the cysts are a symptom of PCOS and not the cause. There is still scientific debate regarding the precise mechanism of PCOS. But at its core, PCOS refers to having too much LH (lutenizing hormone, which creates androgens) and too little FSH (follicular stimulating hormone, which creates estrogens). So in PCOS, there are too many androgens. High androgens leads to hirsutism (male patterned hair growth) and virilization (male secondary sex characteristics). One of the defining features of PCOS is that ovulation is messed up, which leads to infertility. It also causes fatigue, mood swings, abnormal sex drive and weight gain.
Obesity is important in PCOS. Let's start with fat cells. Adipose cells create estrogen (specifically they synthesize estrone, the weakest of the estrogens). While estrone can contribute to negative feedback (less FSH release), it’s simply too weak to create the big LH spike that drives ovulation. So no ovulation occurs. Without ovulation, the follicle doesn’t degenerate into the corpus luteum (so no progesterone). The follicle persists. Driven by estrone, it grows into a cyst. One more problem with estrone is that it also impacts the uterus, and unopposed estrogen increases the risk of endometrial cancer. Obesity and insulin resistance are a big part of PCOS, which is why weight loss is one of the primary treatments. Not everyone with PCOS is obese, but the classic PCOS patient is overweight. This is a nasty feedback loop, because obesity is both a symptom and a cause of PCOS.
All patients are encouraged to lose weight. In patients who aren’t planning to conceive, you should give birth control (to rebalance the estrogens) and metformin (to reduce insulin resistance). If the virilization is especially problematic, anti-androgen drugs like Spironolactone, Finasteride and Flutamide may be helpful. To treat infertility, the gold standard drug is Letrozole, the aromatase inhibitor. The second line agent is Clomiphene, which tricks the hypothalamus into thinking that it needs to make a lot of FSH.
Black is the normal function
Red is the PCOS pathway
Gold is for drugs
OVARIAN TORSION
Gonad attack
Ovarian Torsion refers to when an ovary’s blood supply twists on itself until it’s compressed. The absence of blood flow leads to infarction, like a heart attack of the gonad. Torsion is rare under normal circumstances, but it becomes more likely whenever there’s an adnexal mass (ovarian cyst or tumor). I guess that a mass distorts the architecture of the pelvis in such a way that it allows the ovary to spin. Ovarian ischemia causes sudden unilateral lower abdominal pain accompanied by nausea and vomiting. The ovarian artery can sometimes torse and un-torse spontaneously, leading to intermittent attacks of pain. That can make it pretty difficult to recognize torsion. Ovarian torsion is a medical emergency, just like its cousin, testicular torsion. Without prompt surgical detorsion, the ovary will be permanently lost. The diagnosis is intuitive -- you look for the absence of blood flow on a doppler ultrasound.
OVARIAN CANCER
Benign
Cancer
EPITHELIAL TUMORS are the most common tumors of the ovaries. The ovaries are surrounded by a layer of epithelium that extends along the fallopian tubes. The epithelium is damaged every time that ovulation occurs, as the egg literally explodes out of the gonad. Therefore, women who’ve had lots of periods (early menarche, late menopause, nulliparity, never taken birth control) are at higher risk. Most patient are post-menopausal. Other risk factors include BRCA1, BRCA2, Lynch syndrome, PCOS, endometriosis and old age. While the other ovarian tumors are notorious for secreting hormones, the epithelial tumors are pretty inert. Of note, they do secrete a marker called CA-125. Since a handful of other ovarian problems (endometriosis) can elevate the CA-125, it’s not useful as a screening test, but it does come in handy when tracking the progression of an epithelial cancer over time. They like to spread locally, especially into the peritoneum. Peritoneal invasion causes vague symptoms like abdominal distention, bloating, early satiety, fatigue and weight loss. Modern research suggests that most of these tumors probably originate on the fallopian tubes, which is why salpingectomies are increasingly recommended over tubal ligations.
Ovarian Adenomas are the most common neoplasms of the ovaries. They’re common and (mostly) harmless -- big ones can precipitate mass effect-related problems of the adnexa (ovarian torsion).
Ovarian Carcinomas are cancers of the ovarian epithelium. This is the most common cancer of the ovaries. They come in two varieties - mucinous (tons of white goop) or serous (lots of glands, making clear fluid). The serous variety sometimes features a big circular blob of calcium on histology, called a Psammoma body, which looks a lot like the cross-section of a geode.
GERM CELL TUMORS are descended from the egg stem cells. They contain blueprints for many different tissues (fetus, placenta, yolk sac, etc). Each one of those blueprints can become cancerous. Average age of onset is younger than epithelial cancers.
Dysgerminomas are cancers of the self-replicating stem cells. Its testicular counterpart is called a Seminoma. Under a microscope, they’re called fried egg cells because they have a circular shape, large clear cytoplasms (the egg white) and prominent nuclei (the yolk). It has a good prognosis, and responds well to radiation. LDH is often high, as well as beta-hCG.
Choriocarcinoma is a cancer of the placenta. The trophoblastic cells proliferate and secrete beta-hCG. Beta-hCG leads to positive pregnancy tests and bilateral theca-lutein cysts. While anyone with ovaries can get a Choriocarcinoma, you usually see them in the months following a pregnancy (that includes molar and ectopic pregnancies). Choriocarcinoma spreads rapidly through the blood (classically to the lungs).
Yolk Sac Tumors (aka Endodermal Sinus Tumors) are cancers of the yolk sac. They are the most aggressive ovarian cancer. Look for Schiller-Duval bodies, which kinda look like a glomerulus (blood vessel in the center, and a few concentric layers of cells around it). Serum alpha fetoprotein (AFP) will be elevated.
Teratomas (Greek for “monster tumors”) are neoplasms of embryonic tissues. They’re full of little pieces of babies. Look for cell lines from all three embryological layers (ecto, meso, endoderm).
Immature Teratomas are malignant. They are rich in stem cells and neuroectodermal cells.
Mature Teratomas are light on stem cells, and heavy in mature tissues (like hair, teeth, bones, etc). They are mostly benign. There are two interesting (but rare) subtypes to keep in mind. Some Teratomas are filled entirely with thyroid glands (Struma Ovarii), and they pump out a ton of T3 / T4, which causes hyperthyroidism (with a low TSH). And while mature teratomas are usually benign, sometimes the teratoma’s own skin cells can become cancerous (squamous cell carcinoma)!
STROMAL TUMORS are descended from anything else in the ovary.
Granulosa Cell Tumors do what granulosa cells do normally -- make estrogen! High estrogen levels can lead to weird puberty in a child, endometrial hyperplasia / vaginal bleeding in a woman or cirrhosis-like symptoms in men. Histology shows Call-Exner bodies, where a group of cells encircle a pink blob of fluid. Inhibin levels are elevated.
Thecomas do what theca cells normally do, which is make androgens. However, the androgens are quickly converted to estrogen.
Sertoli-Leydig Cell Tumors make testosterone, and feature Reinke Crystals on histology (pink rods). Ovaries don’t have any Sertoli or Leydig cells, but they do hold the blueprint for those cells in their DNA.
Fibromas are benign neoplasms of fibroblasts, full of connective tissue. Some patients also get pleural effusions and ascites (Meigs Syndrome)
METASTASES aren’t especially common to the ovaries, but here are two high yield examples.
Krukenberg Tumors are bilateral ovarian mets that originate from stomach cancer.
Pseudomyxoma Peritonei begins as an appendix cancer that spreads into the peritoneum, and it involves a the overproduction of mucus (“jelly belly”).