Endo is fickle, it can grow anywhere, and if it is not growing in the gynae region then there is no reason why you would exhibit any of the most commonly seen endo symptoms because they all relate to pelvic endo it being the most common location for endo to manifest itself.
Pulmonary endo may be the only location of endo in your body at the present time, if it is that. Because it is found in one location doesn't automatically mean it is in any other given location. It's purely pot luck where those cells decide to nest and be active.
They could be there from when you developed as a foetus, they could have wandered there more recently.
What is known is if you do have active endo, then is doesn't know it is not in the uterus where is is supposed to be. It still acts like your womb cells every month, responding to hormones floating round the body, growing a menstrual lining and then shedding it causing bleeding where ever in the body it appears to be nesting.
Having it removed entirely is the main goal for all surgery and especially thoracic endo sites. It doesn't prevent new endo at some point in the future, but it does get rid of the existing stuff which is half the battle.
After surgery on the existing stuff, then you would need a long term plan to stop or considerable reduce the nuber of periods you have in a year and there are many ways to do that with BC pills, IUDs, arm implants, injections etc.They don't all suit every one, so a bit of trial and error is required to find the one that best suits your long term plans.
If endo is found and not biopsied and removed then it can and will spread unless something is done to alter your hormones to prevent the endo being active and risking a subsequent lung collapse.
If it is endo, then every period will be putting you at risk of a similar incident until such time as an endo specialist thoracic surgeon can remove it.
Use the search box on the green bar at the top of the page and type in Catamenial
or Pneumothorax. Lung endo is very rare in comparison with pelvic endo, but as over 10% of all women in the world have endo somewhere, there will still be a lot of ladies who have had or are battling with the extra dangers associated with lung endo.
Catamenial Pneumothorax out of the blue in otherwise fit and healthy females of a young age who are on or just had a period, must be considered very high in the list of suspected causes for a Pneumothorax. A&E staff are much more aware of this risks in recent years than they ever used to be.
I wouldn't hang about doubting the doctors judgement on this one. If it does turn out to be endo the quicker it is identified & removed the very much better your health prospects.
It is the most potentially dangerous form of endo in terms of requiring sudden emergency life saving care, so please don't hesitate to have it seen to asap.
There are a number of ladies who are on the forum who have had this and have had treatment, browse the search box and you should find a few previous discussions.
There's a pretty good report on this form of endo - it is a bit academic but still, it doesn contain a lot of useful info.
And please do not worry about your fertility. this could be the only site of endo in your body and no where near threatening your ovaries or tubes. Endo is like that, it can be anywhere. it is only when it is active and bleeding right next to ovaries and tubes that it becomes a fertility risk factor. If no where near them, then your fertility chances are no different to any non-endo lady.
Even if they do find other patches of endo elsewhere , the body is a very large and busy place and endo could be just about anywhere else, on any ligaments, organs or tissues. There may be one or two, twenty or thirty or hundreds of lesions or blisters of endo, your body could be riddled with it and still not have any threatening the ovaries and fallopian tubes.
I've had endo over 30years - stage 4 severe, it is just about everywhere in the pelvic area, and yet both my tubes were still clear, one ovary was stuck inside an endometrioma cyst but the other wasn't. As i said, we are each a unique case in where endo decides to grow and how much of it we get, so please don't fret about fertility. With no pelvic endo symptoms at all, there's no reason to suspect any endo would be there, but I'm sure they will take a look in any case during your op to make sure all is well below the diaphragm.
Very best of luck getting the lung issue dealt with whatever the cause may be. Hope it is fully curable with surgery if it turns out to be endo, and your lungs don't bother you again in the same way.