Carcinoid Tumor of Thymus: A Rare But Highly Recurrent and Metastatic Disease

Abstract

SESSION TITLE: Disorders of the Mediastinum 1 SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Primary carcinoid tumor arising in thymus is rare with very few cases reported. Recurrence and metastases are common. We present a case of carcinoid tumor of thymus that recurred 6 years post treatment. CASE PRESENTATION: 28 yo female presented with adrenocorticotrophic hormone( ACTH) secreting low-grade carcinoid tumor of thymus causing Cushing syndrome. She underwent trans-sternal thymectomy and adjuvant radiotherapy. Postoperative CT scan and ACTH levels were stable for 5 years with no evidence of disease. Several month prior to presentation to us she noted a left neck mass , her ACTH levels rose and she was admitted for pneumonia. CT and Positron Emission Tomography (PET) scans demonstrated PET-avid mass in the left neck just behind the sternocleidomastoid, and along the right internal jugular lymph node chain. Fine needle aspiration of the left supraclavicular mass demonstrated neuroendocrine carcinoma. She underwent successful resection of the mass along with extended left neck dissection with en-bloc resection of the internal jugular vein down to the left subclavian junction including thoracic duct resection and bilateral lymphadenectomy of jugular nodes. Post surgery her ACTH level declined from 81-19.7 pg./ml ( Normal:10-50 pg/ml) DISCUSSION: Carcinoid tumors are unusual tumors and account for less than 5 % of all anterior mediastinal tumors. It is incidentally found in over one third of patients. Others present with signs and symptoms of rapidly expanding mass such as cough, chest pain, superior vena cava syndrome. At least 20% have metastases at presentation with extra thoracic disease in 20-30%. Almost 50% are functionally active and associated with endocrinopathies such as Cushing syndrome as in our patient and multiple endocrine neoplasia. Invasion of adjacent structures such as in our patient occur in 30-50% and metastases to lung, bone and liver in about 30%. Surgical resection is the treatment of choice although recurrence is 67% and often after long intervals. Radiotherapy and chemotherapy is recommended but without clear-cut benefit. Survival varies and in one review 51% survived three years, 27% survived five years and 9% survived 10 years or more CONCLUSIONS: Thymic carcinoids are slow growing aggressive tumors, which commonly invade surrounding structures. Despite extensive resection late recurrence may occur. Reference #1: Carcinoid tumor of the thymus. Thorax 1994; Wang et al Reference #2: Primary Neuroendocrine carcinoma of thymus: Niger med J 2013 jan feb:Gaude et al DISCLOSURE: The following authors have nothing to disclose: Bikash Bhattarai, Kevin Kovitz, Benjamin Seides No Product/Research Disclosure Information