Inhibin B levels...

Hi there, I was diagnosed in 2004 with an adult granulosa cell tumor of my right ovary for which I had a complete hysterectomy and bilateral salpingo-oopherectomy. I have been having my inhibins drawn since surgery and it has always come back undetectable. This last time my inhibin b level was 114 which is elevated from the normal <16 range. Inhibin A was normal as was my estradiol. I am concerned and not sure what to do next. Any advice would be greatly appreciated.

[Annekathryn Goodman, M.D.]

Hi There
first I would repeat the test and make sure it is not a lab error
If it is still elevated, the next step is a CT scan to look for any growths that could be producing inhibin such as a recurrence of the granulosa cell. It is curious that the inhibin a is normal which is another reason to double check that this is not a lab error. I have pasted the discussion on inhibin from emedicine. please let us know what your repeat level is
take care

Inhibin

Inhibin is a peptide hormone normally produced by ovarian granulosa cells. It inhibits the secretion of follicle-stimulating hormone (FSH) by the anterior pituitary gland. It reaches a peak of 772 +/- 38 U/L in the follicular phase of the menstrual cycle and is normally undetectable in the serum of menopausal women. Granulosa-cell tumors produce inhibin and its serum levels reflect the the tumor burden. Measurement of inhibin can be used as a marker for primary as well as recurrent granulosa cell tumor.

The recent availability of markers of ovarian stroma, including melan-A and inhibin-alpha, has provided a means for the positive identification of ovarian stromal tumors, which can manifest in a myriad of histological appearances.

The hormonal activity of granulosa cell tumors permits the use of a variety of serum tumor markers in the diagnostic evaluation. Clinically, the most useful serum marker for granulosa cell tumors is inhibin. Inhibin exists in 2 different isoforms, inhibin A and inhibin B. Both isoforms consist of a dimer of 2 subunits, the alpha and beta subunits. The alpha subunit is the same for both isoforms, while the beta subunits differ (beta A and beta B) and show about 64% homology. The 3 subunits (alpha, beta A, beta B) are produced on separate genes located on chromosomes 2 (alpha and beta B) and 7 (beta A).

Inhibin usually becomes nondetectable after menopause. However, certain ovarian tumors, mostly mucinous epithelial ovarian carcinomas and granulosa cell tumors, produce inhibin. An elevated inhibin level in a postmenopausal woman or a premenopausal woman presenting with amenorrhea and infertility is suggestive of the presence of a granulosa cell tumor, but not specific. Inhibin levels can also be used for tumor surveillance after treatment to assess for residual or recurrent disease. Although most commercial laboratories only provide assays for inhibin A, serum levels of inhibin B seem to be more frequently elevated. Whenever available, the use of assays is suggested that detect both isoforms. The free alpha subunit can also be measured.

http://emedicine.medscape.com/article/269839-overview

[pcrosley]

Hi,

Our foundation maintains a large on-line library of research on GCT.  Based on some articles there, we would recommend adding Anti-Mullerian Hormone (AMH) or Mullerian Inhibiting Substance (MIS, 2 different names for the same test) to your suite of blood tests.  Here is an extract for 1 article:

"The sensitivity of inhibin B and AMH for diagnosing patients with a progressive disease is rather equivalent. Antimüllerian hormone is a more specific serum parameter than inhibin, because inhibin may also increase in some (mucinous) epithelial ovarian tumors. Nowadays, specific and ultrasensitive assays are commercially available as well for inhibin B as for AMH, so that early detection of GCT might be possible. For patients with elevated levels of inhibin B and/or AMH at initial diagnosis of GCT, inhibin B and/or AMH seemed to be reliable markers during follow-up for early detection of residual or recurrent disease. Elevated concentrations of these hormones predict relapse earlier than clinical symptoms, which leads to less morbidity of the patients. In conclusion, inhibin B and AMH are both useful serum markers for diagnosis and especially for follow-up of patients with a GCT. Currently, there is no evidence-based preference for inhibin B or AMH as tumor marker."

Geerts, et. al., International Journal of Gynecological Cancer:
July 2009

Check out our web site, www.gctf.org.nz

Kind regards,
Powel Crosley
Granulosa Cell Tumour Foundation New Zealand

[Annekathryn Goodman, M.D.]

Dear Powell
thank you for your excellent comments

[TammyStP]

Hi there,
I don't really have an update yet, but my regular OB/GYN has been in contact with Dr. Donovan (who has replaced Dr. Prefontaine) at Baystate Medical Center and it has been suggested that I have a repeat Inhibin B, a repeat CT scan, and a chest x-ray around  8 weeks from my last blood draw. When all of this is scheduled, they will also schedule me for an appointment with Dr. Donovan. This puts me back into testing mode around the third week of March....so I am still playing the "waiting game." Based on Mr. Crosley's comment, do you think it's worth asking to have the AMH included in my labwork? Do you by any chance know if Dr. Donovan uses this test as a marker for GCT? Hopefully I'm not being presumptuous, but I am assuming that she may have contact with you as Boston is usually the next step after Baystate if they don't feel they can handle certain situations. Thanks again for your help, Tammy

[TammyStP]

I am supposed to call on Monday to start scheduling everything, and still haven't heard back on my last question.... I was looking forward to hearing your thoughts on this. I guess I will just skip asking about the AMH and see what happens...
Thanks anyway, Tammy

[Annekathryn Goodman, M.D.]

HI There
I would wait until your appointment with Dr Donovan. AMH may or may not be an available test at Baystate. Dr D will let you know. She will take good care of you
best wishes