The association between papillary thyroid carcinoma and thyroiditis was first reported in 1955, since then questions remain about prognosis, particularly regarding lymph nodes and distant metastases.

We report a prospective study carried out in a hospital center in Algeria between 2020 and 2022 which included 267 papillary thyroid cancers, of which 97 (36.3%) patients had thyroiditis. The patients benefited from a total thyroidectomy with lymph node dissection in 142 (52.8%) of them. The latter was prophylactic in 105 (39.3%). Among these 105 patients, thyroiditis was present in 40 (38.1%) patients, only 4 (10%) of them had lymph node metastases. no significant difference between thyroiditis and lymph node metastases (p 0.18). On the other hand, post-operative complications were noted in 13 (32.5%) patients with thyroiditis with a significant difference between the presence of thyroiditis and the occurrence of post-operative complications (p 0.02).

In situations of thyroiditis, we find more multifocality in papillary thyroid carcinoma, which has raised the interest in prophylactic lymph node dissection in these patients. However, many authors believe that lymph node invasion in this situation doesn't worsen the prognosis, the cancer cell invading the lymphatic network expresses a specific thyroid antigen whose autoimmune antibody causes the cell to remain localized only in the lymph node. On the other hand, due to the inflammation of thyroiditis, surgery is more laborious, exposing patients to more post-operative complications.

The indication for central lymph node dissection doesn't seem to differ from its indication outside the context of thyroiditis.