Management of pituitary tumor recurrences: surgery

Abstract

While, following a century of technical developments and refinements, primary surgery of pituitary tumors to date is efficacious and affected with only a low complication rate, any kind of re-operations is technically more difficult. The lack of reliable anatomical landmarks, tissue changes from implants, the development of arachnoceles and scarring impair orientation in the operative field. Thus, statistically, the success rate in terms of total tumor resection and normalization of excessive hormonal production is much lower, once previous surgery has been performed. Tumor size increase observed on other treatments, visual worsening by chiasmal compromise or ophthalmoplegia, an uncontrolled over secretion of growth hormone, ACTH or TSH, justify a surgical redo-procedure. Whether a transsphenoidal or transcranial approach is employed must be decided on tumor extension, configuration and on the route that was chosen for primary surgery.. The goal of surgical treatment is the best possible resection of the tumor mass, decompression of visual pathways and reduction of hormonal over secretion whilst hopefully preserving normal glandular function and avoiding potential surgical complications. Apart from the tumor's size, extension, configuration and the magnitude of hormonal over secretion, the individual skill and experience of the surgeon is another important factor. With microsurgical techniques and standard approaches, mortality is beyond 1%, but morbidity is higher than in primary operations. The outcome of surgery in respect to remission in secreting adenomas is being reviewed on the basis of pertinent literature. The indications and outcomes in terms of tumor are illustrated based on a few representative patients. The author comments on the value of several new technical supports such as neuronavigation, endoscopy and intraoperative imaging as applied to reoperations in pituitary adenomas.