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4 slides generated from the cancer page, with a quiz from the open benchmark and speaker notes that cite the sources. Arrow keys move between slides; Print gives one slide per page.
A thyrotroph tumour is a very rare pituitary tumour that secretes TSH, driving the thyroid to overactivity with a TSH level that is not suppressed. It is often mistaken for common hyperthyroidism and wrongly treated by destroying the thyroid, which makes the pituitary tumour grow. Surgery is the treatment of choice; somatostatin analogues control most of the rest.
The 2022 WHO classification places the thyrotroph tumour in the PIT1 lineage, defined by TSH-beta and GATA3 staining (Asa 2022). The European Thyroid Association guideline notes that TSH-secreting tumours are characterised by high free thyroid hormones with non-suppressed TSH, that failure to recognise them may lead to inappropriate thyroid ablation with a significant increase in pituitary tumour mass, that diagnosis rests on TSH response to T3 suppression and TRH stimulation together with imaging and genetic testing to exclude thyroid hormone resistance, and that surgery is the treatment of choice with somatostatin analogues normalising TSH in most surgical failures (ETA 2013). In 90 consecutive patients operated on between 1991 and 2013 (47 women, median age 42, range 11 to 74), 18 percent were microadenomas and 82 percent macroadenomas, microadenomas becoming more frequent recently, 23 percent invaded the cavernous sinus, 74 percent were firm or hard, and co-secretion of growth hormone or prolactin occurred (J Neurosurg 2014).
How it differs from its parent: its syndrome mimics Graves disease, so the diagnostic trap is thyroid rather than pituitary; the tumours are often fibrous and invasive, making complete resection harder; and somatostatin analogues are unusually effective medically.
| Setting | Approach | Guideline |
|---|---|---|
| All cases | Transsphenoidal surgery after achieving euthyroidism; somatostatin analogues for residual disease; radiotherapy where medical control fails (ETA 2013). | not mapped |