An interesting case of pituitary adenoma presenting as an invasive nasopharyngeal tumor
A 47-years-old man presented in the otorhinolaryngology department with a 4 month history of chronic left sided nasal obstruction, periodic epistaxis along with pain and difficulty in opening left eye. He also complained of frontal headache. Patient suffered from diabetes mellitus since last 10 yrs and had proliferative diabetic retinopathy in right eye.\nOn examination, patient had frontal sinus tenderness. There was complete third nerve palsy on left side []. Other cranial nerves were not affected. There was no periorbital edema. Ocular examination on right side was normal. There was no blackish discoloration of nasal or palatal mucosa. There was no conductive deafness. Patient was provisionally suspected of having an invasive nasopharyngeal malignancy or rhino-ocular mucormycosis of paranasal sinuses. However, nasal endoscopy revealed sphenoid sinus filled with expansive firm tumor. Biopsy from the mass showed nests and cords of synaptophysin positive cells with uniformly looking nuclei accompanied with necrotic fibro connective tissue consistent with possibility of pituitary adenoma with extensive necrosis. In view of the histopathological diagnosis, magnetic resonance imaging (MRI) of sella was planned and endocrine consultation was done.\nMRI revealed a heterogenous mass lesion in sphenoid sinus extending posteriorly in pituitary fossa with stalk displaced posteriorly and pituitary gland not separately discernible from the lesion. The fat plane between the pituitary gland and lesion was effaced [Figures –]. Upon endocrine evaluation, the patient had evidence of anterior pituitary hypofunction in the form of weakness, easy fatigability, reduced libido, nausea, vomiting, and increased episodes of hypoglycemia. He denied of having polyuria. Thyroid stimulating hormone (TSH) was 0.213 μIU/ml (0.2-5.1μIU/ml) with a free thyroxine (T4) of 0.6 ng/dl (0.95-2.25 ng/dl). Cortisol measured at 8:00 am was 4.93 μg/dl (5-23 μg/dl). His prolactin (PRL) level measured in serial dilutions was 2.0 ng/ml (2.7-17.0 ng/ml). Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH) levels were normal. Transnasal transsphenoidal surgery was planned after optimization of thyroid and adrenal status. Postoperatively hormone supplementation was continued. Histopathological examination confirmed the diagnosis of pituitary adenoma. On immunohistochemistry, the cells were positive for synaptophysin and negative for prolactin, Adrenocorticotropic hormone (ACTH), and growth hormone (GH) markers. So the diagnosis was consistent with chromophobe adenoma of pituitary.