Thyroid C-cell hyperplasia in an adolescent with neurofibromatosis type 1.
BACKGROUND
Subjects with neurofibromatosis type 1 (NF1) show an increased risk of endocrine tumors, especially pheochromocytoma, whereas thyroid C-cell hyperplasia (CCH) and medullary thyroid carcinoma (MTC) are very rare events described only in adult patients.


METHODS
A case of CCH diagnosed in a 14-year-old girl affected with NF1 is reported. Calcitonin serum level after pentagastin was elevated (286 pg/ml). Genetic testing was performed in order to rule out mutations in the RET proto-oncogene.


RESULTS
No germline mutation previously reported in MEN2 was detected. Multifocal and bilateral CCH was demonstrated by immunohistochemistry.


CONCLUSIONS
It is suggested that in such a genetic background of high risk for malignancy, CCH could be considered as an extremely rare condition likely preceding MTC.
Segni
M
M
Department of Pediatrics, University 'La Sapienza', Rome, Italy. m.segni@mclink.it
Massa
R
R
Bonifacio
V
V
Tartaglia
F
F
Pucarelli
I
I
Marzullo
A
A
Pasquino
A M
AM
D002648:Child; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D009456:Neurofibromatosis 1 / Q000473:pathology*; D000090063:Proto-Oncogene Mas; D013961:Thyroid Gland / Q000473:pathology*