Neuroendocrine neoplasms of the orbit: report of three cases and a literature review

Abstract

Neuroendocrine neoplasms (NENs) originate from neuroendocrine cells, and mainly occur in the gastrointestinal tract and lungs, rarely occurring in the orbit. Here, the clinicopathologic factors, treatments and prognosis of three cases of orbital NENs are described. The mean age of the three patients (two females and one male) was 59 years. Two cases exhibited ocular symptoms, including unilateral proptosis and eyelid mass, while the third case presented systemic symptoms exhibited as Cushing’s syndrome. The tumours were surgically resected in all three patients. Immunohistochemistry assays revealed positive expression for pan cytokeratin and epithelial membrane antigen in all cases. Additionally, neural cell adhesion molecule 1 (also known as CD56) and synaptophysin were positive in two cases. The pathological diagnosis for case 1 and 2 was ‘neuroendocrine carcinoma’ and both patients died three months after diagnosis. Case 3 was diagnosed with a neuroendocrine tumour and the symptoms of Cushing’s syndrome gradually improved following surgery. In addition, no recurrence was observed during the four-year follow-up period. These cases demonstrate that orbital neuroendocrine tumours show different clinical manifestations due to the different types. Pathology may clarify the diagnosis, classification and grading, and provide a reference value for treatment and prognosis.

Diagnostic and Therapeutic Management of Primary Orbital Neuroendocrine Tumors (NETs): Systematic Literature Review and Clinical Case Presentation

“…The laterality of ocular involvement was right and left in 11 and 5 cases, respectively, and the initial symptoms were mostly represented by proptosis or exophthalmos (n = 11.69%), ocular pain (n = 3.19%) and the loss of or reduction/alteration in vision (n = 5.31%). Neurological symptoms [26,27] and Cushing's syndrome [28,29] were described in only two cases, respectively. The histological diagnosis was available for all patients, according to the histopathological classification used at the time of publication of the different cases: "carcinoid" was described in five cases, well-differentiated NETs in two, and NEC/poorly differentiated carcinoma/small-cell NEC in the remaining nine.…”

“…The clinical presentation is often characterized by a progressive orbital mass with proptosis, swelling, and visual disturbances such as diplopia, unilateral blindness, and blurry vision, while only a few cases are associated with pain and neurological symptoms such as headaches or neuropathy [26,27]. A small number of orbital primary neoplasms can secrete hormones, leading to carcinoid syndrome with the ectopic release of adrenocorticotropic hormone (ACTH) [28,29]. Therefore, although Cushing's Syndrome is mainly associated with neuroendocrine lung cancers [79,80], it should be taken account of as an uncommon but described clinical occurrence of this rare NEN localization.…”