Background: Isolated absent thelarche is a rare condition that is infrequently reviewed in the literature.
Case: A 28-year-old woman with neurofibromatosis type 1 and acromegaly presented with absent breast development despite hormone therapy. Examination noted a normally developed woman with acromegalic features and Tanner stage I breasts. Hormone studies and karyotype were normal. Magnetic resonance imaging of the patient's brain demonstrated a voluminous pituitary. Chromosome microarray analysis diagnosed the neurofibromatosis 1 microdeletion syndrome. Breast ultrasonography and surgical consultation were offered.
Conclusions: Neither neurofibromatosis type 1, acromegaly, nor neurofibromatosis 1 microdeletion syndrome are linked to absent thelarche. After attempting hormone therapy, patients with absent thelarche should be evaluated for congenital breast anomalies, estrogen receptor abnormalities, or gene defects. Psychological and surgical consultation should also be offered.