Granular cell tumor (GCT) mimicking a nonsecreting anterior pituitary adenoma

Tumor de células granulares (TCG) mimetizando um adenoma hipofisário não produtor

A 33-year-old male with right eye amaurosis and panhypopituitarism previously submitted to surgery and radiotherapy was admitted with a presumptive recurrence of a nonsecreting pituitary macroadenoma (the first diagnosis, in another service). Magnetic Resonance Imaging (MRI) confirmed an expansive solid isointense lesion in the posterior region of the sella with suprasellar component (Figure 1). After a new surgery, histological revealed granular cell tumor (GCT) (Figure 2).

Figure 1
Sagittal T1-weighted MRI showing a circumscribed sellar/suprasellar mass (A) with homogeneous contrast enhancement (B). The lesion is predominantly hypointense on T2-weighted image (C, coronal). In all the images, there was absence of the normal pituitary bright spot.

Figure 2
In the first surgical sample, the lesion showed morphological features essentially similar to those observed in the second specimen. Cells with cytoplasmic granules (A; Hematoxylin-eosin), which do not contain glycogen (B; Periodic Acid-Schiff with diastase digestion) and correspond to lysossomes (C: electron microscopy). In the first surgical sample, the lesion showed morphological features essentially similar to those observed in the second specimen.

GCT of the CNS is rare¹.This report emphasizes the importance of this differential diagnosis in preoperatory for solid lesions with suprasellar component, homogeneous enhancement, and hyperattenuated on CT since they are more vascular and tend to bleed more than macroadenomas².

References

• ¹ Covington MF, Chin SS, Osborn AG. Pituicytoma, spindle cell oncocytoma, and granular cell tumor: clarification and meta-analysis of the world literature since 1893. Am J Neuroradiol. 2011;32(11):2067-72. doi:10.3174/ajnr.A2717
• ² Aquilina K, Kamel M, Kalimuthu SG, Marks JC, Keohane C. Granular cell tumour of the neurohypophysis: a rare sellar tumour with specific radiological and operative features. Br J Neurosurg. 2006;20(1):51-4. doi:10.1080/02688690600600996

Publication Dates

• Publication in this collection
  13 Oct 2015
• Date of issue
  Dec 2015

History

• Received
  10 Apr 2015
• Reviewed
  05 June 2015
• Accepted
  25 June 2015