Sporadic Adrenocorticotropic Hormone-Secreting Lung Carcinoids: Outcomes of Long-Term Clinical Follow-Up at a Single Center

Objective: Lung carcinoids represent a small portion of all lung tumors and about 1%-5% are associated with ectopic adrenocorticotropic hormone secretion, representing 1%-10% of Cushing's syndrome. They occur both sporadically and rarely in association with multiple endocrine neoplasia type 1. MEN1 variations were detected in approximately 16% of sporadic cases with seldom reports about disease prognosis. This study aimed to identify MEN1 variants in our cohort of sporadic lung carcinoids to associate with disease outcome following surgery. Methods: Pathologically confirmed 5 lung carcinoid cases were retrospectively analyzed in terms of age, gender, imaging studies, clinicopathologic features, and long-term disease outcome. Genetic analysis was performed to detect copy number variations and point mutations in MEN1. Results: Totally 1 female and 4 males with cushingoid features underwent thoracoscopic lobectomy for ectopic Cushing's syndrome. Histopathological examinations revealed 2 atypical (males) and 3 typical (1 female and 2 males) carcinoids. One underwent Wedge resection, the others underwent lobectomy; none of them had any post-operative complications. Median follow-up period was 11 years (range, 5-19); all patients were alive with no recurrence or metastases, up to date. Genetic analysis revealed a novel MEN1 variant [c.1623G>T, p.(Gln541His)] in only 1 atypical carcinoid. Despite this variant, this case did not develop other components of MEN1 syndrome during long-term follow-up. Conclusion: We detected the frequency of MEN1 variation as 20%. Further studies are required to clarify the role of this variant.