Surgery for acromegaly: Indications and goals

Abstract

Acromegaly is a disease that occurs secondary to high levels of GH, most often from a hormone-secreting pituitary adenoma, with multisystem adverse effects. Diagnosis includes serum GH and IGF-1 levels, and obtaining an MRI pituitary protocol to assess for a functional pituitary adenoma. Attempted gross total resection of the GH-secreting adenoma is the gold standard in treatment for patients with acromegaly for a goal of biochemical remission. Medical and radiation therapies are available when patients do not achieve biochemical cure after surgical therapy.

Keywords: acromegaly; adenoma; endonasal; endoscopic; pituitary; skull-base; transnasal.

Figure 1

Depiction of Knosp definitions of cavernous sinus invasion (31). Please see Table 1 for descriptions of the Knosp grades.

Figure 2

A 33-year-old man with a GH-secreting microadenoma. Preoperative MRI, T1-post gadolinium contrast, featuring sagittal (A) and coronal (B) views that demonstrate a small adenoma, confined to the pituitary sella. 3-month postoperative MRI, T1-post gadolinium contrast, sagittal (C) and coronal (D) views show gross total resection of the lesion, with well-vascularized nasoseptal flap. More than 1 year from surgery, there is no residual tumor as demonstrated by the sagittal (E) and coronal (F) MRI T1-post gadolinium contrast. The patient achieved biochemical cure after resection of the GH-secreting adenoma.

Figure 3

A 43-year-old woman with a giant GH-secreting pituitary adenoma. Preoperative MRI, T1-post gadolinium contrast, featuring sagittal (A) and coronal (B) reveal a massive, invasive tumor, invading into the brain parenchyma, bilateral cavernous sinuses, and clivus. The T2 coronal sequence (C) shows the invasion into the right frontal lobe. Immediate postoperative MRI, T1-post gadolinium contrast, sagittal (D) and coronal (E) views shows radical resection of tumor, with scant residual in the cavernous sinus. A fat graft and nasoseptal flap were employed. 1-year postoperative there is a small amount of residual tumor in the cavernous sinuses, as demonstrated by the sagittal (F) and coronal (G) MRI T1-post gadolinium contrast. The patient achieved biochemical remission after initiation of octreotide. No radiation was needed.

Figure 4

A 40-year-old man with a recurrent GH-secreting macroadenoma. His first surgery was completed at an outside institution. Preoperative MRI, T1-post gadolinium contrast, featuring sagittal (A) and coronal (B) views that show a macroadenoma with bilateral Knosp 3 invasion into the cavernous sinuses. 3-month postoperative MRI, T1-post gadolinium contrast, sagittal (C) and coronal (D) views show radical resection of the lesion, with very small residual in the left Knosp 3A compartment. More than 1 year from surgery, there is stable residual tumor in the left cavernous sinus as demonstrated by the sagittal (E) and coronal (F) MRI T1-post gadolinium contrast. The patient achieved biochemical remission with lanreotide.