Endocrine Abstracts

Introduction: The combination of poly/monostotis fibrous dysplasia, café-au-lait pigmentation of the skin and endocrine hyperfunction (mostly precocious puberty) is known as McCune–Albright syndrome (MAS), a genetic origin syndrome with low incidence. The molecular basis of MAS is a mosaic activating mutation of the α subunit of the G protein (Gsα) gene.

We present a clinical case of a 10-year-old boy with partial MAS and GH-secreting pituitary adenoma treated with octreotide-LAR.

Clinical case: The patient at the age of 5 years manifested headache and growth acceleration (10 cm per year). At 10 years, he was 176.6 cm tall. Examination revealed elevated serum GH (20 ng/ml, supression during OGTT minimum to 11.3 ng/ml), IGF1 (1176 ng/ml), IGF-BP3 (362 nmol/l) and prolactin (2480 IU/l). MRI found a pituitary microadenoma and CT showed signs of fibrous dysplasia of frontal, sphenoid and ethmoid bones. No café-au-lait spots or other endocrinopathy was observed. The therapy with octreotide-LAR and cabergoline was started. During 4 years of follow-up patient developed normal puberty and grew up on 27 cm. Lab tests showed normalisation of prolactin (with no elevation during 2-year self-withdrawal period) and appearance of secondary hypothyroidism. He receives octreotide-LAR 40 mg for at least 2 past years and cabergoline 0.25–1 mg per week. The decrease of IGF1 (to 700–800 ng/ml which is within the 95th percentile) and GH (minimum to 7.3 ng/ml) were observed. In 4 years of treatment, IGF1 level rose again to 1182 ng/ml. No CT and MR signs of tumor progression/reduction or deterioration of bone lesions were seen.

Conclusion: We report a clinical case of MAS in a child associated with GH-secreting adenoma treated conservatively with octreotide-LAR. The therapeutic response was insufficient and curative treatment was required. Despite there is a partial MAS with few organ involvement, the specifity of endocrinopathy determines a burden of the disease.