Extracapsular en bloc resection in pituitary adenoma surgery
A pituitary pseudocapsule often contains tumor tissue and should be removed for radical resection. It can be used as a surgical plane for more radical resection of the tumor in many cases of pituitary adenomas. We evaluated the advantages and disadvantages of extracapsular en bloc capsulectomy.
From 1992 until 2011, 1,089 treated patients were grouped according to the resection technique: en bloc capsulectomy, fragmented capsulectomy, or piecemeal resection. Their surgical and endocrinological outcomes and complications were evaluated.
Extracapsular tumor resection was performed in 263 patients; en bloc capsulectomy in 94 patients and fragmented capsulectomy in 169, whereas piecemeal resection was performed in 826. Extracapsular resection was performed more frequently in prolactin- and thyroid-stimulating hormone-secreting tumors. Total resection was more frequently achieved in extracapsular resection and its chance was 100 % when tumors were removed in an en bloc fashion. For the functioning pituitary adenomas, endocrinological remission was achieved in all patients whose tumors were removed in an en bloc fashion and there was no recurrence. Postoperative cerebrospinal fluid (CSF) rhinorrhea developed in 4.2 and 2.7 % in the extracapsular resection group and the piecemeal resection groups, respectively. The chance of postoperative aggravation of pituitary function was not statistically different between groups.
Extracapsular resection is critical for radical tumor resection and endocrinological remission. The removal of a pseudocapsule does not increase the risk of postoperative hypopituitarism nor postoperative CSF rhinorrhea.
KeywordsCapsulectomy En bloc resection Extracapsular resection Pituitary adenoma Pseudocapsule
The authors thank Juyoon Park, R.N., M.P.H., O.C.N., Min Kyeong Jang, R.N., Sung Ja Kang, R.N., and Bok Soon Lee, R.N., Pituitary Tumor Clinic and Soo Yeon Choi, M.P.H., Department of Medical Recording for their tremendous effort in performing the endocrinological tests and data acquisition for such a long follow-up duration.
Conflict of interest
The authors report no conflict of interest concerning the materials or methods used in this study and there was no financial support or relationship with any organization.
Video 1. A 38-year-old male patient with a growth hormone-secreting pituitary adenoma. The tumor was removed as one piece with preservation of a normal pituitary gland. A small defect of arachnoid was sealed completely. The tumor was removed completely and biochemical remission was achieved. (MPG 20257 kb)
Video 2. A 49-year-old male patient with a growth hormone-secreting pituitary adenoma. After internal debulking of the tumor, the tumor capsule was carefully dissected from the surrounding normal pituitary gland. The tumor was removed completely without leakage of cerebrospinal fluid and biochemical remission was achieved. (MPG 9694 kb)
Video 3. A 44-year-old male patient with a thyroid-stimulating hormone-secreting pituitary adenoma. In en bloc fashion, the tumor was removed completely. The remaining normal pituitary gland was preserved without leakage of cerebrospinal fluid. After surgery, biochemical remission was also achieved. (MPG 9621 kb)
Video 4. A 51-year-old male patient with an endocrine-inactive pituitary adenoma. As piecemeal resection was impossible because of very hard consistency of the tumor, outer dissection was performed along the tumor capsule. The tumor was completely removed in en bloc fashion. (MPG 14750 kb)