Ruolo della resezione laringo-tracheale nella patologia maligna tiroidea: descrizione di un caso e revisione della letteratura

Well-differentiated thyroid carcinomas infiltrate into the respiratory tract in between 0.9 and 7% of the cases. Laryngeal-tracheal involvement--most often discovered intra-operatively--can substantially modify the surgical approach. It should be evaluated pre-operatively through laryngo-tracheoscopy with a flexible fibroscope and, in some selected cases, using CT or NMR. Thyroidectomy, associated with laryngeal-tracheal resection and termino-terminal anastomosis, ensures good oncological results without any negative effect on the incidence of post-operative complications. The present work reports the case of a 64-year-old patient who, for 5 months, had presented a swelling of increasing consistency in the left hemithyroid, fixed on the deep planes. Echography showed a 5 cm mass in the left lobe and thyroid isthmus, without suspected lymphadenopathy for metastasis. Fine needle cytology was compatible with papillary carcinoma. CT using a contrast medium revealed an infiltration into the left antero-lateral wall of the I and II tracheal ring, with submucosal extension with no significant signs of stenosis of the airway. Esophagogastroscopy was normal while tracheobroncoscopy confirmed the radiological picture and made it possible to perform a tracheal biopsy which proved positive for papillary carcinoma. The patient underwent total thyroidectomy associated with anterior compartment lymphadenectomy and crico-tracheal resection of the cricoid arch and the first 5 tracheal rings. When surgery was completed, the patient was extubated without complications. Post-operative recovery was uneventful and the patient was discharged on the 9th day after surgery. Histopathological examination confirmed the pre-operative diagnosis and made it possible to stage the lesion as pT4N1bM0 because of the presence of one prelaryngeal lymph node metastasis and another one at the right paratracheal space. Complementary I131 therapy was scheduled along with periodic laryngo-tracheoscopic controls. 16 months after surgery the anastomotic line is perfectly healed and the patient is clinically disease free. A review of the literature on the surgical treatment of well-differentiated malignant thyroid neoplasms with respiratory tract involvement through resection and laryngo-tracheal anastomosis has made it possible to trace the indications, limits and results of this type of therapeutic approach.