Lanreotide-ATG effectiveness on tumoral mass shrinkage of two thyrotropin-secreting pituitary macroadenomas
Amalia Paniagua1, Ignacio Bernabeu2 & Monica Marazuela1
Context: There is scant evidence of tumoral mass reduction in Thyrotropin-secreting pituitary adenomas (TSPA) treated with long-acting somatostatin analogs. There are no reports that evaluate TSPA shrinkage after deep subcutaneous (sc) Lanreotide-ATG (L-ATG) therapy.
Objective: The primary objective was to observe if L-ATG could reduce TSPA tumor mass.
Methods: A literature review on the subject was made. The biochemical and radiological evolution of two TSPA macroadenomas treated with L-ATG for more than 12 months are presented.
Results: Case 1: A 47-year-old man underwent trans-sphenoidal removal of a 60 mm pituitary adenoma, with no hormonal immunochemistry reactivity. One month after surgery he showed elevated α?subunit, TSH and FT4. MRI demonstrated persistence of a 30 × 55 mm sellar mass. He received monthly deep sc 120 mg L-ATG treatment for 13 months. Campimetric amelioration and hormonal tests normalization were achieved after the first L-ATG dose. After 3 months of treatment MRI revealed a tumor mass of 30 × 30 mm (a shrinkage >45%). After 13 months the tumor size was 25 × 30 mm.
Case 2: A 37-year-old man underwent trans-sphenoidal surgery for a 19 mm pituitary adenoma seven years before consultation for clinical hyperthyroidism. He showed elevated FT4 with inappropriately normal TSH and a positive pituitary pentetreotide uptake coinciding with a 35 × 17 mm pituitary mass in MRI. Treatment with monthly deep sc 120 mg L-ATG was administered for 17 months with normalization of FT4 levels. On the 10th month of treatment MRI showed no residual tumor and at the end of follow-up there were no clinical signs of hyperthyroidism.
Conclusion: These two case-reports show a positive role of L-ATG in TSPA tumor mass shrinkage.