Surgical management of Cushing's syndrome

Prevalence of Nelson's syndrome after bilateral adrenalectomy in patients with cushing's disease: a systematic review and meta-analysis

PURPOSE

Bilateral adrenalectomy (BA) still plays an important role in the management of Cushing's disease (CD). Nelson's syndrome (NS) is a severe complication of BA, but conflicting data on its prevalence and predicting factors have been reported. The aim of this study was to determine the prevalence of NS, and identify factors associated with its development.

DATA SOURCES

Systematic literature search in four databases.

STUDY SELECTION

Observational studies reporting the prevalence of NS after BA in adult patients with CD.

DATA EXTRACTION

Data extraction and risk of bias assessment were performed by three independent investigators.

DATA SYNTHESIS

Thirty-six studies, with a total of 1316 CD patients treated with BA, were included for the primary outcome. Pooled prevalence of NS was 26% (95% CI 22-31%), with moderate to high heterogeneity (I² 67%, P < 0.01). The time from BA to NS varied from 2 months to 39 years. The prevalence of NS in the most recently published studies, where magnet resonance imaging was used, was 38% (95% CI 27-50%). The prevalence of treatment for NS was 21% (95% CI 18-26%). Relative risk for NS was not significantly affected by prior pituitary radiotherapy [0.9 (95% CI 0.5-1.6)] or pituitary surgery [0.6 (95% CI 0.4-1.0)].

CONCLUSIONS

Every fourth patient with CD treated with BA develops NS, and every fifth patient requires pituitary-specific treatment. The risk of NS may persist for up to four decades after BA. Life-long follow-up is essential for early detection and adequate treatment of NS.

Corticotroph tumor progression after bilateral adrenalectomy (Nelson's syndrome): systematic review and expert consensus recommendations

BACKGROUND

Corticotroph tumor progression (CTP) leading to Nelson's syndrome (NS) is a severe and difficult-to-treat complication subsequent to bilateral adrenalectomy (BADX) for Cushing's disease. Its characteristics are not well described, and consensus recommendations for diagnosis and treatment are missing.

METHODS

A systematic literature search was performed focusing on clinical studies and case series (≥5 patients). Definition, cumulative incidence, treatment and long-term outcomes of CTP/NS after BADX were analyzed using descriptive statistics. The results were presented and discussed at an interdisciplinary consensus workshop attended by international pituitary experts in Munich on October 28, 2018.

RESULTS

Data covered definition and cumulative incidence (34 studies, 1275 patients), surgical outcome (12 studies, 187 patients), outcome of radiation therapy (21 studies, 273 patients), and medical therapy (15 studies, 72 patients).

CONCLUSIONS

We endorse the definition of CTP-BADX/NS as radiological progression or new detection of a pituitary tumor on thin-section MRI. We recommend surveillance by MRI after 3 months and every 12 months for the first 3 years after BADX. Subsequently, we suggest clinical evaluation every 12 months and MRI at increasing intervals every 2-4 years (depending on ACTH and clinical parameters). We recommend pituitary surgery as first-line therapy in patients with CTP-BADX/NS. Surgery should be performed before extrasellar expansion of the tumor to obtain complete and long-term remission. Conventional radiotherapy or stereotactic radiosurgery should be utilized as second-line treatment for remnant tumor tissue showing extrasellar extension.

Adrenal Incidentaloma: Review of 197 Patients and Report of a Drug-Related False-Positive Urinary Normetanephrine Result

PURPOSE

To determine the incidence and importance of functioning tumors among incidentally discovered adrenal masses in the era of laparoscopic surgery.

METHODS

We defined adrenal incidentaloma as a tumor detected during abdominal imaging for adrenal-unrelated reasons, and we reviewed 197 consecutive patients with adrenal incidentaloma diagnosed since we started laparoscopic adrenalectomy.

RESULTS

Incidentaloma was discovered initially in 91 (46%) patients and pheochromocytoma was detected as an incidentaloma in 21 (39%) of 54 patients. One patient, a 21-year-old woman taking mesalamine for ulcerative colitis, had a remarkably elevated urinary normetanephrine level, which resulted in the initial misdiagnosis of a 10-cm right adrenal incidentaloma as a pheochromocytoma. Laparoscopic right adrenalectomy resulted in a pathological diagnosis of ganglioneuroma. A series of urinary normetanephrine measurements were taken in parallel with the mesalamine doses. We found that other patients medicated with mesalamine, without adrenal tumors, had elevated urinary normetanephrine levels, confirming that mesalamine metabolites interfere with urinary normetanephrine measurements.

CONCLUSIONS

It is essential to diagnose the functional potential of adrenal incidentaloma preoperatively, and not to perform laparoscopic adrenalectomy for adrenal incidentaloma without careful evaluation first.

Six cases of ectopic ACTH syndrome caused by thymic carcinoid

The ectopic ACTH syndrome (EAS) caused by thymic carcinoid is rare and its diagnosis remains a challenge to the endocrinologist. Here are six cases of EAS with a typical Cushing habitus accompanied by hyperpigmentation and hypokalemia. For all six patients, the high dose (8 mg) dexamethasone suppression test (HDDST) showed lack of suppression, computed tomography (CT) scanning documented anterior mediastinal masses, and the mediastenal tumors removed were confirmed as ACTH secreting thymic carcinoids by positive ACTH and NSE staining. Our data indicate that HDDST chest radiologic imaging and other laboratory examinations will greatly assist in diagnosing the thymic carcinoid-induced EAS at an earlier stage, which will significantly improve the long-term survival of the patient.

Laparoscopic bilateral adrenalectomy for Cushing's syndrome due to ACTH-independent macronodular adrenocortical hyperplasia

We performed simultaneous bilateral laparoscopic total adrenalectomy in two patients with Cushing's syndrome due to ACTH-independent macronodular adrenocortical hyperplasia (AIMAH). Preoperative serum cortisol in the patients was 29.5 and 53.2 microg/dl, respectively. The clinical symptoms of the latter patient were advanced, and respiration was labored with orthopnea. Laparoscopic adrenalectomies were performed transabdominally in the sequential lateral decubitus positions with extension of the lateral abdominal wall of the affected side. Three 12-mm and three 5-mm trocars were positioned, and two trocar sites in the midline were used on both sides. The flexible fiberscope was inserted through the umbilical port. The adrenal glands were large, fragile, and multinodular. The maximal diameters of the removed glands were 7.8 and 8.7 cm, respectively. In both patients, the adrenal glands were successfully removed without fragmentation. The operation times were 505 and 320 min, and the estimated blood loss was 150 and 5 ml, respectively. Neither intraoperative nor postoperative complications occurred, although the latter patient required muscle training before ambulation on postoperative day 42. The procedures resulted in marked clinical improvements. Compliance with the substitutive therapy remained excellent, and the patients expressed a very high degree of satisfaction with the laparoscopic adrenal surgery. The procedures of bilateral laparoscopic adrenalectomy were successful, and provided increased experience with the laparoscopic techniques.

Laparoscopic adrenalectomy for incidentaloma and bilateral adrenal disease

Adrenalectomy is ideally suited to minimally invasive surgery based on the characteristics of adrenal tumours, which are usually small and benign. The aim of this study was to verify that laparoscopic adrenalectomy is minimally invasive and to assess the indication of laparoscopic adrenalectomy for incidentaloma. From October 1995 through August 2002, 133 patients underwent adrenal surgery at the Department of Surgery II, Nagoya University School of Medicine. Of these, 111 underwent laparoscopic adrenalectomy. All laparoscopic adrenalectomies were performed using the transabdominal lateral approach. In 50 of 133 patients, the adrenal tumours were incidentally discovered. There were 27 non-functioning adrenal tumours and six of seven preclinical Cushing's test syndrome cases incidentally discovered. Six of 27 non-functioning adrenal tumour patients underwent open adrenalectomy because of large tumour size or malignancy. Based on the present criteria for laparoscopic adrenalectomy, 15 of 133 patients were retrospectively considered to have required open adrenalectomy. The average size of a non-functioning adrenal tumour was 5.8 cm in diameter, which was equal to the average size of a phaeochromocytoma. A simultaneous bilateral laparoscopic adrenalectomy was performed in a patient in poor condition with advanced Cushing's syndrome due to adrenocorticotrophic hormone-independent macronodular adrenocortical hyperplasia (AIMAH). The adrenal glands were successfully removed without fragmentation in this patient, and the postoperative course was uneventful, thanks to the minimally invasive surgery. The laparoscopic technique assures less morbidity and faster recovery, and appears to be equally effective in eradicating functioning and non-functioning adrenal masses. The benefits of the laparoscopic approach to adrenalectomy should not result in a more aggressive attitude toward the excision of clinically silent, benign-appearing adrenal incidentalomas.