Which of the following is not involved with multiple endocrine neoplasia-I?

MEN-1 or Wermer syndrome Characterized by abnormalities : - Parathyroid: Primary hyperparathyroidism is most common manifestation of MEN-1. It is initial manifestation of disorder in most patients, appearing in almost all patients by age 40 to 50. - Pancreas: Endocrine tumors of pancreas are leading cause of morbidity & moality in these pts. Tumors are usually aggressive & often present with metastatic disease. Multiple "microadenomas" scattered throughout pancreas in conjunction with one or two dominant lesions are seen. - Pituitary: Prolactinoma is the frequent anterior pituitary tumor encountered in MEN-1