A Sertoli cell nodule, also Pick's adenoma, testicular tubular adenoma and tubular adenoma of the testis, is a benign proliferation of Sertoli cells that arises in association with cryptorchidism (undescended testis). They are not composed of a clonal cell population, i.e. neoplastic; thus, technically, they should not be called an "adenoma".
Sertoli cell nodules are unencapsulated nodules that consist of:
1. cells arranged in well-formed tubules (that vaguely resemble immature Sertoli cells), with
2. bland hyperchromatic oval/round nuclei that are stratified, and
3. may contain eosinophilic (hyaline) blob in lumen (centre).