Pituitary collision tumors are sporadically reported and rare. We present a case of pituitary collision tumors with nonfunctioning pituitary adenoma (NFPA) and craniopharyngioma. In order to look for any common activated pathway, we examined WNT/β-CATENIN signaling activation, known to be involved in tumorigenesis in both craniopharyngioma and NFPA. We found nuclear accumulation of β-CATENIN protein and expression of LEF1 protein, markers of active β-CATENIN signaling in the craniopharyngioma but not in the pituitary adenomas. In our case, the NFPA is invasive macroadenoma, which is a frequently identified type of pituitary adenoma in collision tumor cases. Recurrence of this tumor was first observed after 8 years of follow-up. Based on this case, we suggest that pituitary collision tumors require long-term follow-up.
Bibliographical noteFunding Information:
This study is supported by grants from the Graduate School, University of Minnesota (UMF0011528 to T.A., Grant-in-Aid 212588 to T.A.) and a grant from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR064195 to Y.K.). We are grateful to Dr Mike O'Connor for the use of LSM710 confocal microscope and to Ms Cailin McMahon for editorial assistance.
© Endocrine Society 2020.