Objective : To report the case of a patient with a medullary thyroid microcarcinoma (MTmC) metastatic
Methods : The clinical and paraclinical characteristics of the patient are described.
Results : A 55-year-old man presented a widening of the mediastinum on a chest x-ray that was requested due to progressive dyspnea, nonproductive cough and dysphagia. CT of neck and thorax reports right thyroid nodule and mediastinal tumor in right upper mediastinum of 58mm in diameter that displaces surrounding structures. In view of the progress of the described symptomatology, the patient is operated on urgently. The pathological anatomy reported NET with Ki67 10% so it is referred to continue study and treatment by endocrinology. Due to the concurrence of a thyroid nodule in the patient, the possibility of a metastatic MTC vs. MTC in a submerged thyroid was considered. The study was complemented with thyoid ultrasound plus FNAB + needle wash for calcitonin, serum calcitonin and CEA, and thyroid scintigraphy. Ultrasound and FNAB was positive for a 10x7x9mm nodule, Bethesda VI with characteristics of MTC; Thyroid scan reported thyroid in normal position and configuration; calcitonin levels: 1113ng/ml and CEA: 518ng/ml, calcitonin wash> 1000ng/ml. Imaging studies for staging (CT, octreoscan, PET-CT) demonstrated pulmonary, mediastinal, and vertebral involvement. Given the disjunctive of metastatic MTmC vs. mediastinal NEC producing calcitonin metastatic to thyroid was requested an extension of pathological study of the mediastinal tumor, which was positive for calcitonin and TTF1. No findings of MEN2. The patient receives chemotherapy and radiotherapy, we do not have ITK for CMT in our country.
Discussion : Although cases of metastatic MTmC are rare, there have been reports of cases of lymph node and lung metastases. The presence of positive calcitonin and amyloid material, which are typical histological features of a MTC in addition to very high values of calcitonin and above all CEA, typical of advanced MTC, lead us to conclude our diagnosis as a metastatic to mediastinal MTmC initially.
Conclusion : Thyroid microcarcinoma is defined as a tumor less than or equal to 10mm in its maximum diameter. The majority correspond to papillary carcinomas, while medullary microcarcinoma is infrequent and its presentation is even more rare as distant metastasis.
Jose PAZ-IBARRA– ENDOCRINOLOGIST, HOSPITAL NACIONAL EDGARDO REBAGLIATI - UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS. LIMA - PERU, Lima, Lima, Peru
Victor Garcia– ENDOCRINOLOGY RESIDENT, HOSPITAL REBAGLIATI - LIMA - PERU, Lima, Peru
Jorge Merchan– ENDOCRINOLOGY RESIDENT, HOSPITAL REBAGLIATI - LIMA - PERU, Lima, Peru
HOSPITAL NACIONAL EDGARDO REBAGLIATI - UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS. LIMA - PERU
Lima, Lima, Peru
PERUVIAN ENDOCRINOLOGIST, UNIVERSITY TEACHER, ACTIVE MEMBER OF AACE, AREAS OF INTEREST NEUROENDOCRINOLOGY, THYROID, ENDOCRINOLOGY OF REPRODUCTION AND BONE MINERAL METABOLISM
HOSPITAL REBAGLIATI - LIMA - PERU, Lima, Peru