Acromegaly diagnosis – blood tests to diagnose acromegaly

Your doctor may suspect that you have acromegaly because of physical changes-your feet and hands may have grown, in addition to facial changes. Abdominal sarcoma surgery Some doctors may even ask to see older photographs of you so that they can compare facial features. Canine histiocytic sarcoma (You can read more about the physical changes in the article on acromegaly symptoms). Endometrial stromal sarcoma symptoms However, to make an accurate diagnosis of acromegaly, he or she will need to run some tests.


Diagnosing acromegaly involves 2 key blood tests: a test to check the level of the insulin-like growth factor-1 (IGF-1) and an oral glucose tolerance test (OGTT).

Doctors can’t simply test for the level of growth hormone (GH) in your body because the level varies so much in one day—even in someone without acromegaly. What is a sarcoma cancer That means that a doctor could randomly test for GH and get a normal level in a person with acromegaly. Treatment for sarcoma muscle cancer However, because of GH fluctuations, the doctor could also test GH levels in someone without acromegaly and get a level far above normal.

Insulin-like growth factor-1 (IGF-1) is a hormone that’s closely tied to growth hormone. Adult ewing sarcoma GH tells the body to make IGF-1, which in turn causes tissues in your body to grow. Alveolar soft part sarcoma survival rate In someone without acromegaly, a high IGF-1 level is the body’s signal to stop producing GH. Ewing sarcoma relapse For a person with acromegaly, though, the body continues producing GH, regardless of high IGF-1 levels.

IGF-1 levels are much more constant throughout the day than GH levels, so doctors measure IGF-1 levels using a blood test. Sarcoma lump under skin An elevated IGF-1 level may indicate acromegaly.

Growth hormone levels and blood glucose levels are also connected. Kaposi sarcoma treatment In someone without acromegaly, a higher blood glucose level usually causes the body to stop producing GH. Soft tissue sarcoma types Therefore, a doctor will purposely raise your blood glucose level using an OGTT and watch how your GH level responds.

To begin the test, your doctor will measure your blood glucose level and your GH level. Metastatic sarcoma symptoms You’ll then drink 75 g of a very sugary drink—a glucose drink. Sarcoma malignant Over the course of the next 2 hours, the doctor will test your glucose and GH levels 4 more times: 30, 60, 90, and 120 minutes after you’ve had the glucose drink.

If your GH level doesn’t drop to below 1 ng/mL (ng/mL is the standard measurement used for GH levels) during the OGTT, you have acromegaly. Sarcoma cancer treatment options Your GH level should respond to so much glucose by dropping, so if it doesn’t, that tells the doctor that your body isn’t listening to its own signals: The delicate feedback loop of the endocrine system has been disturbed. Pleomorphic sarcoma symptoms (To learn more about the endocrine system feedback loop and how it regulates itself, you can read our endocrine system overview.

Since 95% of acromegaly cases are caused by a pituitary tumor, the doctor will most likely have a magnetic resonance imaging (MRI) scan done of your pituitary gland. Sarcoma in kids The MRI should show the doctor exactly where the tumor is and how big it is.

If you have an MRI done and the doctor can’t see a pituitary tumor, then you may be one of those rare cases of acromegaly caused by a non-pituitary tumor. Muscle sarcoma survival rate In that case, the doctor may order a computerized tomography (CT) scan of possible tumor sites (abdomen and chest are common sites). Tissue sarcoma Additionally, the doctor may test your growth hormone-releasing hormone (GHRH) levels since often, non-pituitary tumors causing acromegaly make GHRH (which then causes your pituitary gland to over-produce GH).

Diagnosing acromegaly involves a combination of factors: noting physical changes, testing levels of certain hormones in the blood, and confirming the presence and size of a tumor using imaging tests.