Pituitary lymphoma appearing 9 years after pituitary adenoma resection

Abstract

Background: Pituitary lymphomas (PLs) are very rare, accounting for <0.1% of all intracranial tumors. Of which, PL that is associated with PL is even rarer. Here, we describe a case of PL of a 51-year-old woman that appeared 9 years after pituitary adenoma resection.

Case description: A 51-year-old woman presented with visual disturbance. She had a history of pituitary adenoma resected through endoscopic trans-sphenoidal surgery (eTSS) 9 years before. Although her previous annual follow-up did not show any signs of recurrence, she noticed visual disturbance. One month later, her visual acuity rapidly worsened with headache and fatigue, being referred to our hospital. On examination, she had bilateral quadrantanopia. Her laboratory data showed slightly increased prolactin levels. Magnetic resonance images showed a mass in the sella with suprasellar extension, so she underwent eTSS. The tumor had a fibrous, hard part and a soft gray part, and it was mostly resected. Visual symptoms improved transiently, but ophthalmoplegia appeared 2 weeks after surgery, indicating intrathecal dissemination. Histological analysis confirmed the diagnosis of T-lymphoblastic lymphoma. Positron emission tomography showed tracer accumulation at the pancreas, confirmed as lymphoma through biopsy. However, we could not determine which site of lymphoma was the primary site. She underwent chemotherapy, including cyclophosphamide, vincristine sulfate, doxorubicin hydrochloride, dexamethasone, and methotrexate. The patient died despite several months of treatment.

Conclusion: Recurrence of pituitary adenoma cannot be carelessly assumed from a pituitary growing mass after pituitary adenoma resection. PLs have poor prognosis due to their aggressive character. Immediate biopsy and confirmation of the diagnosis are necessary for the treatment of pituitary masses with aggressive features.

Keywords: Endoscopic trans-sphenoidal surgery; Pituitary adenoma; Pituitary lymphoma; Recurrence; T-lymphoblastic lymphoma.

Figure 1:

(a-d) Gadolinium-enhanced magnetic resonance (MR) images before the 1^st operation and 1 year before the presentation. The heterogeneously enhanced tumor is observed in the sella with suprasellar extension before surgery. No tumor recurrence is apparent at 8 years after surgery. MR images at presentation. An extensively enlarged tumor in the sellar and suprasellar portion with optic nerve compression. (e-h) The tumor is shown isointense on T1-weighted images (WI), having iso-low mixed intensity on T2-WI, and heterogeneously enhanced by gadolinium.

Figure 2:

(a: Hematoxylin and eosin (H&E) stain, Magnifications×400) Histological analysis of resected tumor tissue. Tumor cells have round hyperchromatic nuclei and sparse eosinophilic cytoplasm. No apparent necrotic lesion is observed. (b: CD3, c: CD4, d: CD8, e: CD20, f: CD56, g: TdT) Immunohistochemical analysis reveals that tumor cells were positive for CD3, CD4, CD8, and terminal deoxynucleotidyl transferase (TdT) and negative for CD20 and CD56 Magnifications: ×400. Scale bars: 20 μm (a-g).

Figure 3:

(a and b) Postoperative magnetic resonance (MR) images. T2-weighted image (WI) shows the residual tumor attached to the right cavernous sinus and suprasellar portion ([a] Coronal, [b] Sagittal). (c) Gadolinium-enhanced MR fluid-attenuated inversion recovery image taken 14 days after the second surgery shows pial enhancement on the brain stem and cerebellum and indicates intrathecal dissemination. (d and e) Gadolinium-enhanced T1-WI after chemoradiotherapy (11 months after the second surgery) shows an enhanced region in the sellar portion and clivus (arrows) and pial enhancement from the brain stem to the spinal cord (arrowheads).

Figure 4:

Positron emission tomography. Tracer accumulation is seen in the pancreas (arrow). No other tracer accumulation is apparent elsewhere.