Liz hurt her back, so decided to come to see us here at the clinic. Andrew examined her and found something interesting on ultrasound examination: a simple ovarian cyst, nearly the size of a tennis ball. Ovarian cysts are common and can sometimes cause back pain, amongst other symptoms. Often they simply disappear with the passage of time. I have done a brief summary of ovarian cyst issues below:
What are ovarian cysts?
They are fluid-filled sacs within the ovary. They can be divided in to two types: functional cysts (that are related to ovulation) and organic cysts that are more structural.
Why are we interested in them?
Chiropractors are interested in them because they can cause back pain  . A small percentage of them can occasionally turn cancerous, more commonly in post-menopausal women .
Who gets them?
They occur in women of all ages. They are more common before the menopause , but the small percentage that can turn malignant tend to do so post-menopause .
What symptoms do they cause?
Mostly none, but they can cause a variety of symptoms, including back pain. The mechanism for this is unclear, but one possible mechanism is the hydronephrosis caused by an ovarian cyst compressing the ipsilateral ureter . This may explain the flank tenderness sometimes found when examining these patients. They have occasionally been reported to cause sciatica . More common symptoms include abdominal pain or bloating, or a feeling of fullness. Normally, symptoms are not serious, but can be particularly bad if the cyst ruptures. Ovarian cysts may also compress the bladder and cause urinary urgency and can compress the bowel, compromising emptying.
Are they serious?
The concern is whether the cyst is malignant (cancerous) or could possibly turn malignant. Previous guidance  has suggested that cysts are monitored periodically to ascertain whether changes are occurring. There has been a feeling that large cysts are more likely to turn malignant than small cysts, but this seems not to be the case , and there does not seem to be a significant risk of simple ovarian cysts turning malignant. The risk seems to lie with cysts that are more complex.
Multilocular cysts are more likely to be malignant than unilocular cysts .
Cysts with solid parts in them are more likely to be malignant than clear cysts .
Cysts with papillary formations are more likely to be malignant .
The echogenicity of the cyst is not related to malignancy , nor is the presence of septae .
Bilateral cysts are more likely to be malignant than unilateral cysts .
Ovarian cysts that are causing symptoms are of more concern than cysts that are not causing symptoms . This is of concern for the chiropractor, because one of the symptoms of an ovarian cyst is back pain. However, it is quite possible that for some patients the back pain is mechanical and unrelated to the cyst, whilst for others the cyst may play a role in the back pain. No doubt this will be an area for future research.
A CA-125 blood test can be useful to differentiate benign cysts from malignant cysts, but the test can produce results that are falsely negative and falsely positive    .
What happens to ovarian cysts?
In women who are who are premenopausal with normal blood tests and a cyst size of <6cm, it has been shown   that in 50% of the cysts are gone within 6 months and 73% of them gone within 75 months of diagnosis. In postmenopausal women with functional cysts, these too will often disappear within a few months of diagnosis, especially if the woman is less than 60yrs of age 
What is the best treatment for them?
Most ovarian cysts do not require any treatment, and simply regress, as described earlier. If they are large enough, then the suggestion has been that they should simply be monitored periodically , but the benefits of this have been questioned .
The role of aspiration of benign ovarian cysts has been shown to be of benefit in one study  but another study  suggests the opposite. It is to be avoided on any cyst that may be malignant .
The evidence for any role that HRT may play in ovarian cyst treatment is conflicting [27, 28]. Oral contraceptive medication has been shown to be more helpful , but this has to be balanced by the potential other risks of this type of prescription
Ovarian cysts that are considered more likely (as described above) to become malignant, may be considered for surgical removal.
Which is the best type of scan: transabdominal, or internal?
In the clinic here, Andrew will only do TA (transabdominal or external) scanning of the abdomen and pelvis as part of our examination of patients with low back pain. Internal scanning would not be appropriate. However, patients who are referred to hospital for ultrasound scanning will generally have an internal (transvaginal) scan, because the scanning probe can get closer to the ovary and produce a clearer picture. But is internal scanning actually better at looking at the ovary? Whilst it seems intuitively that this should be the case, I can find little published literature that investigates this. One study , admittedly an older one, showed no difference in the diagnosis of polycystic ovaries by transabdominal scanning compared to internal scanning.
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