CDKN1B and parathyroid gland adenoma: Results of LOH studies, using either microsatellites flanking CDKN1B or sequencing the tumoral DNA, revealed allelic loss only in two out of five MEN4-associated tumors (a bronchial carcinoid and a small-cell neuroendocrine cervical carcinoma) (8, 10), but not in a parathyroid adenoma coexistent in the patient with bronchial carcinoid (10).