J Endocrinol Invest (2018) 41:447–454
Diagnosis and treatment of TSH‑secreting adenomas: review
of a longtime experience in a reference center
D. M. Nazato
· J. Abucham
Received: 8 August 2017 / Accepted: 4 October 2017 / Published online: 11 October 2017
© Italian Society of Endocrinology (SIE) 2017
levels were high in nearly all patients with TSH-secreting
adenomas and useful in excluding other conditions in the
diﬀerential diagnosis. Proper indication and interpretation
of simple laboratory tests should be emphasized in medical
education to improve diagnostic accuracy.
Keywords TSH-secreting pituitary adenoma ·
Thyrotropinoma · Pituitary tumors · Hyperthyroidism ·
TSH-secreting pituitary adenomas, also known as thyro-
tropinomas, are among the less prevalent pituitary tumors,
corresponding to 0.9–1.5% of all pituitary adenomas in sur-
gical series [1–3]. In addition to TSH, they usually secrete
the common alpha-subunit of the glycoprotein hormones
(α-SU) and, less frequently, other pituitary hormones, nota-
bly growth hormone (GH) and/or prolactin (PRL).
TSH-secreting pituitary adenomas present with hyper-
thyroidism of various degrees, from mild to clinically severe
thyrotoxicosis, or even asymptomatic, and frequently with
diﬀuse goiter [4, 5] but not exophthalmia. Patients may also
present acromegaly and/or hyperprolactinemia due to the co-
secretion of GH and/or prolactin, respectively. The diagno-
sis is usually suspected when laboratory evaluation reveals
increased free T4 with normal or elevated TSH levels, which
contrasts with the suppressed TSH levels observed in other
forms of thyrotoxicosis.
We retrospectively review our single center experience
in the diagnoses and treatment of 11 patients with TSH-
secreting tumors during the last 25 years.
Purpose TSH-secreting pituitary adenomas are among the
less prevalent pituitary tumors, corresponding to 0.9–1.5%
of all pituitary adenomas in surgical series.
Methods A series of 11 patients with TSH-secreting and
cosecreting adenomas diagnosed and treated in the last
25 years in a single center is described.
Results The mean age at diagnosis was 37 years (range
18–80 years; median 23 years); the ratio of male-to-female
patients was similar (6M:5F). Only three patients was the
correct diagnosis established shortly after the initial medical
evaluation. Other four patients were initially diagnosed with
other pituitary adenomas (prolactinoma, acromegaly, and
non-secreting pituitary tumor) and another four diagnosed
with primary hyperthyroidism. There was a mean diagnos-
tic delay of 6.0 years (range 0.5–25 years; median 2 years).
Nine patients had macroadenomas and two patients had
microadenomas. Seven patients underwent pituitary surgery
which controlled the disease in only two (one micro- and
one noninvasive macroadenoma). The other treatments were
directed to the thyroid gland (surgery or
pituitary radiotherapy, and somatostatin analog.
Conclusion In spite of its relatively straightforward diag-
nosis, which includes clinical/subclinical hyperthyroidism
with or without goiter, increased free thyroxine and non-
suppressed TSH levels, and pituitary mass, the diagnosis
of TSH-secreting and cosecreting adenomas was frequently
unrecognized and thus much delayed. Serum alpha-subunit
* J. Abucham
Neuroendocrine Unit, Division of Endocrinology
and Metabolism, Escola Paulista de Medicina, Universidade
Federal de São Paulo, Rua Botucatu, 806, Vila Clementino,
São Paulo CEP 04023-062, Brazil