Endoscopic and Microscopic Surgery Equally Effective in Cushing’s Disease, Study Finds

Using endoscopic or microscopic techniques to surgically remove the pituitary glands leads to similar remission and recurrence rates in Cushing’s disease patients, a review of 24 studies shows.

The study, titled “Outcome of endoscopic vs microsurgical transsphenoidal resection for Cushing’s disease,” was published in the journal Endocrine Connections.

In endoscopic transsphenoidal surgery, a surgeon uses a tiny camera as a guide, allowing for a panoramic surgical view with increased illumination of anatomic structures. In microsurgical transsphenoidal resection, a surgeon views through a microscope and uses minute instruments or lasers. Both procedures are used in transsphenoidal (TS) surgery to remove pituitary gland tumors, the root cause of Cushing’s disease. In transsphenoidal surgery, a surgeon accesses the pituitary gland through the nose and sinuses.

While endoscopic surgery seems to lead to better patient outcomes, it was unclear before this study if it has any advantages in patients with Cushing’s disease.

To gain more insight into the remission and recurrence rates of both techniques, researchers examined a total of 24 studies that included 1,670 adult patients with Cushing’s syndrome. Of these patients, 702 underwent endoscopic TS, and 968 underwent microsurgical TS.

The study’s authors found that remission rates were similar in both groups. In the endoscopic group, an average of 79.7 percent of patients experienced remission versus 76.9 percent in the microscopic group.

Patients who underwent endoscopic surgery experienced recurrence less often than those who underwent microscopic surgery, with recurrence rates of 11 percent and 15.9 percent, respectively. But researchers pointed out that follow-up times in the studies varied, making comparisons unreliable.

When recurrence rates were calculated by person per year, which takes follow-up time into account, both groups had a recurrence rate of approximately 4 percent per person per year.

Previous studies have shown that complications following either type of surgery occurred at comparable rates. These complications include hypothyroidism (underactivity of the thyroid gland), diabetes insipidus (a condition characterized by increased thirst), CSF leakage (leakage of fluid that normally bathes the brain and spinal cord), visual defects, hypocortisolemia (low cortisol blood levels), and hypogonadism (little or no hormones produced by the sex glands).

“We found that overall remission proportion was the same in CD patients who underwent endoscopic TS compared to patients who underwent microscopic TS. However, patients treated with the endoscopic approach for micro-adenomas were more likely to achieve remission than those treated microsurgically. Patients treated endoscopically were less likely to experience recurrence; however, when follow-up time is taken into account, this advantage disappears,” the researchers concluded.