Endocrine Abstracts

Introduction: Postpartum thyroiditis is an autoimmune process that occurs in 5% of the women, precipitated by immunological rebound. The majority off signet-ring cell carcinoma (SRCC) tumors arise from the stomach, colon and breast, malignant transformation of a bronchogenic cysts being exceptionally.

Aim: We present a case of a rare mediastinal SRCC of the mediastinum, diagnosed initially with a postpartum thyroiditis.

Case presentation: A 34 years old woman presented with complains of neck and anterior thoracic discomfort, agitation, palpitation, 3 months after getting birth. The initial workup found thyrotoxicosis, with high level of thyroid antibodies and autoimmune pattern at ultrasonography, with reduced uptake of Tc-99m pertechnetate at thyroid scintigraphy. Thyrotoxicosis remission, after 2 months of evolution, revealed a superior cava vein syndrome. Chest radiography showed a large mediastinum and cystic-tumor in CT. She associated pericardial effusion, without hemodynamic significance. In spite of sophisticated diagnostic workup, detailed investigations fail to reveal other site implicated at the moment. The tumor resection was complicated with metastatic involvement of the pleura with massive pleural effusion, rising level of the pericardial fluid with carcinomatous signet-ring cells, poor response to treatment and breast metastasis later on. The histopathology and immunohistochemistry of mediastinal mass and breast nodule concluded that it is the case of a very rare mediastinal bronchogenic cyst with malignant transformation in a SRCC. The overall progression was poor with the patient’s death 1 year after diagnosis.

Conclusion: There are limited data about evolution of bronchogenic cysts or SRCC in pregnancy or postpartum and how endogenous estrogens influences tumor’s grow. The malignant transformation of a bronchogenic cyst happens exceptionally. We know that postpartum thyroiditis is precipitated by immunological rebound that follows the partial immunosuppression of pregnancy and malignancy is also an immunosuppressive state, so the association of postpartum thyroiditis in this conditions is uncommon.