Type of transsphenoidal surgery safe, tied to Cushing’s remission
Previous studies indicated procedure was associated with 11% recurrence rate
A type of minimally invasive surgery to remove pituitary tumors through the nose, called endoscopic transsphenoidal surgery, was found to be safe and led to remission from Cushing’s disease, with patients seeing no recurrences, a study in China reports.
The procedure involved identifying pituitary and tumor layers before the tumor’s removal, instead of suctioning or scraping tumor tissue. This contributed to improving the removal of the total tumor and preserving normal pituitary function. The researchers said more research is warranted to confirm the safety and effectiveness of the procedure, given how few cases there are.
The study, “Endoscopic Transsphenoidal Surgery with a Layered Peel Strategy for Cushing’s Disease Treatment: A Case Series,” was published in Brain Sciences.
Cushing’s disease is a form of Cushing’s syndrome caused by benign tumors in the pituitary gland that trigger excessive adrenocorticotropic hormone (ACTH) production. This hormone signals the adrenal glands to produce and release cortisol, leading to Cushing’s symptoms.
The first-line treatment for most patients is transsphenoidal pituitary surgery, wherein the tumor is removed through the patient’s nose and sphenoid sinus, a hollow space behind the nose.
Endoscopic endonasal transsphenoidal surgery lets surgeons directly access and remove the tumor with long instruments placed in the nose. The procedure has become more accessible, but previous studies indicated it was associated with a recurrence rate of 11%.
Researchers from a hospital in China analyzed the clinical characteristics and outcomes of 12 patients with Cushing’s disease treated by endoscopic transsphenoidal surgery using a layered peel strategy. The approach involves identifying pituitary and tumor layers to remove the tumor, instead of suction or curettage (scraping tumor tissue).
Tumor removal
The surgeries were done by a neurosurgeon with extensive experience who’d performed about 1,500 procedures to remove pituitary tumors between January 2014 and September 2022.
All the patients were adults with a mean age of 32.58 and most were female (10). The median time between presenting symptoms and diagnosis was 9.5 months. All showed weight gain and central obesity, and most had facial swelling, round face, purple skin striae, thin skin, acne, and high blood pressure.
MRI scans identified microadenomas in the pituitary gland of all of them, with a maximum tumor diameter from 5 to 11 mm.
In four patients, the tumor was removed by en bloc resection, meaning the entire tumor was removed without opening its capsule. This option was selected when the boundaries between the tumor pseudocapsule — the tissue that surrounds a benign tumor — and the pituitary gland were identifiable, and there was sufficient operating space.
For the remaining eight, the tumor was removed by piecemeal resection and subsequent complete removal of the pseudocapsule. This option was chosen when there was limited operating space.
The researchers described one procedure in detail. Briefly, an instrument called an endoscope was inserted through the nose and the sphenoid sinus was located. A location closest to the tumor was chosen, based on the MRI, to open the pituitary capsule and expose the pituitary gland.
The tumor was removed by piecemeal resection, and then the pseudocapsule was removed. Two days after surgery, an MRI scan confirmed the tumor had been entirely removed. No signs of recurrence were observed in MRI scans three years after surgery.
Remission, low rate of complications
In the 10 patients who had surgery, immediate disease remission was achieved. Delayed remission in the three months after the procedure was observed in the remaining two patients. There were no recurrences at a median follow-up of 51 months (around four years).
Despite the lower rate of surgical complications, two patients developed transient diabetes insipidus, a condition wherein the kidneys are unable to prevent water from being eliminated.
One patient had cerebrospinal fluid discharge, which was resolved by drainage. The cerebrospinal fluid is the liquid that bathes the brain and spinal cord. Another patient had short-term hypopituitarism — low function of the pituitary gland — and was given prednisone replacement therapy.
“Our preliminary experience indicated that [endoscopic transsphenoidal surgery] with a layered peel strategy provided a perfect remission rate, low complication rate, and no recurrence in a case series of [Cushing’s disease] patients,” the researchers wrote.