BackgroundChylothorax is a very rare but major complication in thyroid surgery and should be apparent to clinicians in this field.Case presentationWe report a case with chylothrax after thyroid surgery in our department that drew our attention.MethodsSystematic review of the literature to evaluate the incidence and the contributing factors of chylothorax after thyroid surgery. Database (PubMed) and hand searches to identify patients with thyroid surgery and postoperative chylothorax. Keywords included chylothorax, thyroidectomy, thyroid surgery and complications. Two independent reviewers screened studies against inclusion and exclusion criteria. Patient characteristics, risk factors, symptoms, treatments and etiopathogenesis were investigated.ResultsWe identified 13 articles in the literature describing 19 patients with chylothorax after thyroidectomy and described our own case. Ninety percent of the patients underwent thyroidectomy for thyroid cancer. Sixteen patients (80 %) underwent thyroidectomy with at least a left lateral neck dissection, 2 patients (10 %) underwent thyroidectomy with sternotomy, and in the remaining 2 patients (10 %), thyroidectomy with lateral neck dissection on both sides was performed with partial sternotomy. Our calculated incidence for chylothorax with total thyroidectomy and neck dissection was 1.85 %; for a thoracic approach the calculated incidence was 7.3 %.ConclusionsThere are no reports of chylothorax after thyroidectomy without at least a left lateral neck dissection due to advanced thyroid cancer and/or sternotomy due to the thyroid size. The extension of thyroid surgery seems to be the main risk factor in developing chylothorax either through direct surgical trauma or through increased intraductal pressure after thoracic duct ligation. An early diagnosis of chylothorax may avoid severe metabolic or cardiopulmonary complications.