Pituitary carcinoma with mandibular metastasis: a case report

Abstract

Pituitary carcinomas are rare primary adenohypophyseal tumors with cerebrospinal or extracranial metastasis. The present case, the first report of the disease in Korea, involved a 36-yr-old woman who presented with a 3-week history of headache. Brain magnetic resonance imaging revealed a 2.5-cm sellar and suprasellar mass showing heterogeneous enhancement with suspicious invasion of both cavernous sinuses. The patient underwent gross-total resection. The tumor cells were composed of polygonal cells singly or in variable-sized nests. The nuclei were large and round with prominent nucleoli. The cytoplasms was acidophilic and granular. Marked pleomorphism and frequent mitoses (3 per 10 HPFs) were found. By immunohistochemistry, tumor cells were strongly positive for prolactin, but negative for ACTH and GH. Additional immunostainings for cytokeratin, vimentin, and glial fibrillary acidic protein (GFAP) were negative. After the surgery, the patient received radiotherapy because of the atypical histologic features. The prolactin level fell from 123.17 ng/mL to 5.17 ng/mL after surgery. Nine months after the initial diagnosis, the patient died from mandibular metastasis associated with the pituitary carcinoma.

Fig. 1

Sagittal contrast enhanced T1-weighted image showing a lobulating contoured mass (arrow) with heterogeneous enhancement in the sella. Invasion of the posterior wall of the sphenoid sinus by the sella mass is evident.

Fig. 2

Resected tumor cells showing variable-sized nests and single cells (left lower) mixed with adenohypophyseal cells of normal appearance (right upper) (H&E stain, ×100).

Fig. 3

Tumor cells showing atypical morphology with large round nuclei and prominent nucleoli. The mitoses are 3/10 high power fields (H&E, ×400).

Fig. 4

Tumor cells showing strong and diffuse positive staining for prolactin (Prolactin, ×400).

Fig. 5

(A) Positive immunostaining for p53 in the primary pituitary tumor (×400). (B) High (10%) Ki-67 labeling index (×400).

Fig. 6

Follow-up coronal contrast enhanced T1-weighted image showing an ill-defined heterogeneously-enhanced soft tissue mass (arrow) with destruction of the left mandible. Left oropharyngeal wall-thickening, suggesting spread of the tumor, is also evident.

Fig. 7

Histopathologic and immunologic features of the metastatic tumor showing similarity to that of the primary pituitary tumor (H&E stain, ×400).