A patient with Pancoast's tumour develops hoarseness of voice after radiation, it is due to:

(c) Irradiation to vocal cordsPancoast's tumour is an apical (superior pulmonary sulcus) malignant neoplasm of the lung. The symptoms of this tumour are because of compression of adjacent structures, e.g. sympathetic nerves (Horner's syndrome) and brachial plexus (involvement of C8, T1 and T2; leading to shoulder/ arm pain and weakness and atrophy of hand muscles). Uncommonly the tumour can also compress the recurrent laryngeal nerve leading to hoarse voice and bovine cough.But since the patient has developed hoarseness after radiation, the right answer here is irradiation to vocalcords. Radiation to or near the voice box can lead to edema of vocal cords leading to hoarseness. This radiation injury might heal with time after radiation is completed.Vocal cord infiltration with secondaries is not seen in Pancoast's or superior sulcus tumour. Similarly laryngeal stenosis has not been described after radiation; moreover laryngeal stenosis will lead to stridor.