is it possible to have ovarian cancer

I have Lymphocytic Hypophysitis which is a very rare autoimmune disorder that has affected my entire pituitary stalk with a 5x5x4mm lesion. The first glandular malfunction that was detected was of my adrenal glands. I suffered adrenal crisis stemming from Epidural Steriod Injections for three bulging discs and caused me to be bed ridden for over three months and very ill for close to eight months.  Eventually my adrenal hormones returned to a low normal level but then my Thyroid levels became affected.  Nov 08 my TSH level was 5.60 and DHEA was 656.  I'm told by my endocrinologist (2 hour drive from my extremely rural community) that my autoimmune system may attack any of my glands and have to have my levels monitored closely.  
Before all this I'd been diagnosed with endometriosis and have had 4 laproscopic surgeries over a 10 year period to remove the bad tissue.  Lately, my ob/gyn has suspected that I might have ovarian cancer but won't do a biopsy to confirm for fear that he'll put me in another adrenal crisis and doesn't think the hospital he practices at or the Doctors in the area would be able to handle that situation should it arise.  Additionally, I have pitting edema in both of my legs that has spread as high as my knees, the cause of which has yet to be diagnosed.  His suspicions of possible cancer are based on my body's response to administration of 10 days of Progesterone for each of the last four months, at the end of which I was supposed to start menstruating.  Each time my period didn't start on time, the longest delay being twelve days and the shortest being 5.  Also, the amount of cramping, back pain, clots passed, period irregularity, etc, leads him to want to do a biopsy.
I have three questions:  
1. Is it possible for ob/gyn type cancer (endometrial/ovarian/uterine, etc) to spread to my lymphatic system and cause my autoimmune disorder (Lymphocytic Hypophysitis)?
2. What other non-invasive ways could my ob/gyn diagnose that?  My PCM has requested a referral for a pet or full body scan but my insurance denied the request because of insufficient cause.
3. Would an MRI of the area be helpful for my ob/gyn's diagnosis?
Thank you so much for your time and assistance!

[rumpled]

Did you already have pituitary surgery?

1. to the best of my knowledge, cancers are cancers and auto-immune disorders are separate. One tends to get multiple auto-immune disorders.
2. there are blood tests - e.g. CA-125, etc.
(PS - I have NO adrenals and since my adrenals were removed had a total hysterectomy plus other surgical procedures - all they have to do is give you supportive steroids and viola - no crisis - so I do not understand the issue?)
3. An MRI is so so... I had a CT and an ultrasound. Both of them were wrong when it came to my pathology but at least I had them done but I was a mess as well.

Did your pathology show LH?