Treatment

Under general anesthesia, the patient underwent surgery for the pituitary tumor. Further imaging of the pituitary gland subsequent to surgery revealed residual tumor. He underwent radiation therapy for the residual tumor and has been disease-free since.

Incisional and excisional biopsy

Histological examination of the pituitary tumor revealed sheets of uniform cells, many with granular eosinophilic cytoplasm with central nuclei and some exhibiting more chromophobic cytoplasm and round-to-oval nuclei eccentrically located (Figure 7). Prominent nucleoli were present as well as cells with multiple nuclei. Immunohistochemistry staining revealed uniform and diffuse positive staining with antibody to growth hormone (Figure 8) and focal (minority cells) positive staining with antibody to prolactin (Figure 9).

 

Figure 7 Low power (x100) H & E histology reveals sheets of uniform cells, many with granular eosinophilic cytoplasm with central nuclei and some with more chromophobic cytoplasm and round-to-oval nuclei eccentrically located. Prominent nucleoli were present as well as cells with multiple nuclei.

Figure 8 High power (x200) immunohistochemistry stain reveals uniform and diffuse positive staining with antibody to growth hormone.

Figure 9 High power (x200) immunohistochemistry stain reveals focal (minority cells) positive staining with antibody to prolactin (Figure 9).