Transcript A Case of Secondary Hypogonadism

A Case of Secondary Hypogonadism
“Hypogonadism Due to Pituicytoma
in an Identical Twin”
H. H. Newnham & L. M. Rivera-Woll
New Engl J Med 359: 2824, 2008
W. Rose
Presentation and History
43-year-old man (an identical twin) presents with 2-year history
of lethargy, weakness, headaches; several-year history of gradual
loss of body hair and declining libido. Left orchidopexy at 6 years
of age.
Physical Exam
Shows features of hypopituitarism and hypogonadism, including
central adiposity, nipple pallor, proximal muscle wasting,
preservation of scalp hair, loss of body hair, gynecomastia, and
right and left testicular volumes of 12 ml and 5 ml, respectively
(normal volume, >15). Note contrast in appearance between
hypogonadal patient (Panel A, right) and unaffected identical
twin (left).
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Laboratory Tests
Testosterone: 1.5 nmol per liter (normal range, 9.9 to 27.8).
Follicle-stimulating hormone: 2.8 IU per liter (normal range, 1.5
to 12.4)
Luteinizing hormone: 1.5 IU per liter (normal range, 1.7 to 8.6).
Serum prolactin, thyroid function (measured by free thyroxine
and thyroid-stimulating hormone), cortisol: normal.
Insulin-like growth factor 1 level: mildly decreased.
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Imaging
Magnetic resonance imaging of the pituitary showed a lobulated,
contrast-enhancing suprasellar mass (16 by 29 mm; seen in the
coronal view in Panel B [arrow] and in the sagittal view in Panel C
[arrow]). Images of the unaffected twin are shown for
comparison.
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Pituicytoma, MRI
Normal, MRI
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Diagnosis
Pituicytoma = pituitary cell tumor, confirmed by pathological
analysis of tissue obtained from needle biopsy and subsequent
surgery.
Treatment
Tumor excision by craniotomy.
Followup
Apart from a seizure, patient's postoperative recovery on
pituitary-replacement therapy has been uneventful, with
resolution of his symptoms.
Newnham, H.H. & L.M. Rivera-Woll (2008), New Engl J Med 359: 2824.
Comments
Pituitary tumors usually grow slowly, don’t metastasize, and can
be effectively treated by surgical removal.
Pituitary tumors can be secretory or non-secretory. A secretory
tumor makes one or more of the hormones made by a normal
pituitary, but makes the hormones in an uncontrolled way (i.e.
too much).
W. Rose
Discussion Questions
1. Why are testes small and testosterone low?
2. Why is L testis smaller than R?
3. What do FSH & LH do, and where are they produced?
4. In a male with a normal pituitary, how would FSH and LH levels
respond to low testosterone? Compare to this patient.
5. Why are levels of prolactin, thyroid hormone and TSH, cortisol,
and IGF-1 checked and reported? (Which are made in pituitary,
which are regulated by pituitary?)
6. Is this pituitary tumor secretory or non-secretory? Why do you
say so?
7. Suprasellar?
W. Rose
Discussion Questions
What symptom might be expected that was not seen?
How would you do a needle biopsy or remove the tumor? What
structures would you be especially careful to avoid?
If anterior pituitary (adenohypophysis) were completely
removed, what hormones would have to be monitored and
replaced exogenously?
If posterior pituitary (neurohypophysis) were also removed, what
hormones would be added to the list?
W. Rose
Conventional
transphenoidal
approach.
Coronal section
W. Rose
Tew, JM, Jr, van Loveren, HR, Keller, JT; Atlas of Operative Microneurosurgery, Volume II; W.B.
Saunders, 2002, retreived on 2009-01-08 from http://www.mayfieldclinic.com/PE-surgpit.htm.
Craniotomy and
subfrontal approach.
Endoscopic transphenoidal approach
http://www.ent.uci.edu/endoscopic_pituitary_tumor.htm
Animation of different surgical approaches to pituitary tumors
available at http://www.skullbaseinstitute.com/animations.htm
W. Rose