Η μελέτη του Δρ Καρβούνη με τους Συνεργάτες-Ερευνητές, που παρουσίασαν στο Διεθνές Συνέδριο, στη Καπεγχάγη, εξετάζει τον ρόλο των αντισωμάτων θυρεοσφαιρίνης (Tg–Abs) στην ανάπτυξη και την επιθετικότητα του καρκίνου του θυρεοειδούς (TC). Τα ευρήματα δείχνουν ότι, σε αντίθεση με τα αντισώματα TPO (TPO-Abs), τα Tg-Abs δεν προσφέρουν προστασία έναντι του TC. Αντιθέτως, φαίνεται πως η αύξησή τους σχετίζεται με την ανοσολογική απόκριση στον θηλώδη καρκίνο του θυρεοειδούς (PTC), ειδικά όταν ο όγκος επεκτείνεται πέρα από την κάψα του θυρεοειδούς. Παρόλα αυτά, η προεγχειρητική αξιολόγηση των Tg-Abs μπορεί να έχει προγνωστική αξία σε ασθενείς με θυρεοειδικούς όζους.
Thyroglobulin Antibodies in Patients with Thyroid Cancer: Autoimmunity or Cancer Immunoediting?
Rodis Paparodis, Evaggelos Karvounis, George Simeakis, Ioannis Androulakis, Dimitrios Askitis, Sarantis Livadas, Andreas Rizoulis, Vasileios Papanikos, Nicholaos Mastronikolis, Dimitra Zianni, Charalampos Massouras, Ilias Perogamvrosi, Anastasios Boniakos, Nicholas Angelopoulos, Dimitra Bantouna, Aikaterini Kapezanou, Ourania Aporelli, Shanawaz Imam, Juan Carlos Jaume
Abstract
Introduction: Highly immunogenic tumors can spontaneously prime protective immunity, thus preventing tumor growth, a phenomenon known as tumor immunity. Autoimmunity, is a distinct form of autoreactive immunity that targets one’s own cells, but in the presence of cancer, it could prove tumoricidal. Thyroid peroxidase antibodies (TPO-Abs) are the hallmark of thyroid autoimmunity. Thyroglobulin antibodies (Tg-Abs), do not appear as effective in their cytotoxic capacity as TPO-Abs, and their role in thyroid cancer development/progression remains unclear. We designed the present study to evaluate their role.
Materials & Methods: We reviewed retrospectively thyroidectomy (Tx) cases operated in 13 centers in Greece and 2 centers in the US over 10 years. We recorded their age, gender, BMI, TSH and Tg-Abs preoperative and histology report. Thyroid cancer (TC) incidence and tumor aggressiveness descriptors were compared between patients with elevated vs. low Tg-Abs titers (Tg-Abs+ ≥30 vs. Tg-Abs- ≤30IU/L).
Results: After collecting n=9643 Tx, we enrolled n=2870 patients, mean BMI of 27.3±5.5Kg/m2, age 47.0±14.5 years; n=2127 (74.1%) were females. Their average TSH was 2.11±5.09IU/L, and Tg-Abs 96.0±614.6IU/L. Tg-Abs- were found in n=2232 (77.8%) patients. TC was present in n=1587 (57.1%) cases, of the following histology: papillary (PTC) n=1487, follicular (FTC) n=35, Hürthle cell (HCC) n=23, medullary n=30, anaplastic (ATC) n=1, poorly differentiated thyroid cancer (PDTC) n=7, other n=3, lymphoma n=1. The larger tumor dimension was 1.5±2.0cm, and the average number of tumor foci was 1.8±1.8, n=26 (1.6%) had gross and n=249 (15.7%) had microscopic extrathyroidal extension (ETE), n=212 (13.4%) had capsular invasion (CI), n=391 (24.6%) had lymph nodes (LNs) metastasis, while n=24 (1.5%) had distant metastases. The incidence of thyroid cancer was not different between the two subgroups (elevated vs. low Tg-Abs titers), as did distant metastases (OR 0.98, p>0.05). Patients with Tg-Abs+ had larger tumors (1.8 vs. 1.4cm), more LNs infiltrated by TC (OR 2.2), more ETE (OR 1.25) and capsular invasion (OR 1.20). Non-PTC histology was less common in Tg-Abs+ patients (OR 0.49) (p<0.05)
Conclusions: Tg-Abs behave differently compared to TPO-Abs as they seem unable to protect from TC. Their rise tends to be a marker of the immune response to the expanding PTC, when this extends beyond the thyroid capsule, and when thyroglobulin might become exposed to the immune system. It remains to be proven if Tg-Abs result from TC immunoediting. However, Tg-Abs titers should be evaluated pre-operatively as they might provide prognostic value to the evaluation of patients with thyroid nodules
