Radiological features and metastatic patterns of thymic neuroendocrine tumours. Issue 5 (May 2018)

• Record Type: Journal Article
• Authors: Araki, T.; Sholl, L.M.; Hatabu, H.; Nishino, M.
• Is Part Of: Clinical radiology. Volume 73:Issue 5(2018)
• Page Start: 479
• Page End: 484
• Publication Date: 2018-05
• Subjects: Medical radiology -- Periodicals; Radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiology -- Periodicals; Societies, Medical -- Periodicals; Medical radiology; Radiotherapy; Electronic journals; Periodicals; 616.0757
• DOI: 10.1016/j.crad.2017.11.025
• Languages: English
• ISSNs: 0009-9260

Abstract

Abstract : Aim: To investigate the clinical and image features of thymic neuroendocrine tumours (NETs), and characterise the radiological patterns of recurrence and metastasis on serial imaging studies. Materials and methods: The study included 14 patients (11 males) with a histopathological diagnosis of thymic NETs (one typical carcinoid, eight atypical carcinoid, and five large cell neuroendocrine carcinoma). Preoperative images were assessed for features of primary tumours. Follow-up imaging studies were evaluated for the patterns of metastasis or recurrence. Results: Underlying endocrine or autoimmune disorders were present in four patients (29%), including multiple endocrine neoplasia (MEN) type 1 ( n= 3) and autoimmune thyroiditis ( n= 1). On preoperative imaging, the primary tumours were commonly lobulate and heterogeneous, infiltrated the surrounding fat, and showed ≥50% abutment of the mediastinal structures, with the mean longest diameter of 14 cm (range: 4.1–28 cm). No significant differences of preoperative imaging features were noted among histopathological subtypes. Metastasis or recurrence was noted in 11 of the 14 patients (79%). Ten patients developed intrathoracic metastasis or recurrence, involving thoracic lymph nodes ( n= 7), pleura ( n= 4), lung ( n= 4), pericardium ( n= 4), and local recurrence in the postoperative mediastinum ( n= 3). Eight of the 11 patients also had extra-thoracic metastasis, involving bone ( n= 6), abdominal lymph nodes ( n= 4), liver, pancreas, kidney, adrenal gland, spleen and brain ( n= 1 for each site). Conclusions: Thymic NETs presented as a large, lobulate, heterogeneous mass with an infiltrative nature. Metastasis and recurrence were frequent, most commonly involving thoracic lymph nodes, while extra-thoracic metastasis to bones and abdominal lymph nodes were also noted. Highlights: Thymic NETs present as a large, lobulated, heterogeneous mass with an infiltrative nature. Metastasis or recurrence is frequent (79%), most commonly in thoracic lymph nodes. Extrathoracic metastasis to bones and abdominal lymph nodes were also common.