Endocrine Abstracts

JOINT1846

Introduction: In contrast to primary thyroid cancer, which usually has a good prognosis, thyroid metastases from other primary tumors are associated with a poor prognosis, as they indicate far advanced primary disease [Zivaljevic V, 2018]. The most common metastatic sites of testicular cancer are retroperitoneal lymph nodes. In clinical practice, metastases in the thyroid are extremely rare (incidence ranging from 0.006 to 0.3%) [Battistella E, 2020].

Case description: A 22-year-old man was referred to the Emergency department due to a painless mass on the left side of his neck that appeared three weeks ago, a decrease in appetite and acute upper respiratory tract infection with negative dynamics that has lasted for three days. The neck ultrasound showed an enlarged left thyroid lobe, with a mixed-structure nodule occupying almost the entire lobe. Enlarged lymph nodes were present in the left supraclavicular and posterior cervical areas. Patient was admitted to the Endocrinology department. Blood tests showed normal thyroid hormone levels, ESR 101 mm/h, increased inflammatory markers. Treatment with NSAIDs was initiated, suspecting a subacute thyroiditis. A biopsy of the neck mass and lymph nodes was performed. The results indicated a mixed germ cell tumor with a high Ki67 proliferation marker. After the CT scan of the chest, abdomen, and pelvic organs, advanced testicular neoplastic process was suspected. After a whole-body PET/CT scan, a metabolically active mass in the right testicle was observed, with the most likely metastases in the liver and in the left supraclavicular, mediastinal, left inguinal region, lungs and neck lymph nodes. Neoadjuvant chemotherapy with BEP (Bleomycin, Etoposide, Cisplatin) was initiated before surgery.

Conclusions: We present an unusual clinical case of advanced testicular germ cell cancer that manifested with thyroid enlargement and metastasis in the neck. Testicular cancer with metastasis of the thyroid is an extremely rare occurrence, only 4 cases in the 40 years period were found in literature [Mattavelli F, 2009 and Favero D, 2024].