Medically responsive amyloidogenic giant sellar-parasellar prolactinoma

Abstract

Background: Giant prolactinomas are rare; among them, the amyloidogenic variant, prolactinomas with extensive spherical amyloid deposits, are rare, with only 30 cases reported with recommendations of surgical management contrary to the routine prolactinoma's medical management.

Case description: We report here a case of giant amyloidogenic prolactinoma in a 32-year-old male patient who had a very atypical presentation in terms of clinical, radiological, and pathological features and responded to dopamine agonist therapy like a normal prolactinoma.

Conclusion: Amyloidogenic giant prolactinomas are rare. Contrary to usual belief, even they remain medically responsive; however, more literature is required to decide their ideal management.

Keywords: Amyloidogenic; Macroadenoma; Parasellar; Pituitary; Prolactinoma.

Figure 1:

Magnetic resonance imaging brain T1 axial, T2 axial, GRE, contrast axial, contrast sagittal and contrast coronal images showing extra-axial heterogeneously enhancing left parasellar mass with positive dural-tail sign (yellow arrow) and intratumoral bleed. GRE: Gradient Echo.

Figure 2:

(a) Histomorphology showing sheets of round/polygonal cells with eosinophilic granular cytoplasm and central nuclei. (b) Interrupted reticulin network- reticulin stain. (c) Spherical amyloid globules-H&E stain. (d) Immunohistochemistry-prolactin stain. (e) Low Ki67 labeling index. (f) Congo red stain highlighting apple-green birefringence.

Figure 3:

Immediate postoperative magnetic resonance imaging brain showing significant residual lesion.

Figure 4:

Contrast magnetic resonance imaging brain showing tiny residual after two years.