Four years previously, a 56-year-old fisherman underwent thyroidectomy for cancer of the thyroid gland. He is now noted to have a single 4 cm lesion in the upper lobe of the left lung. There is no other evidence of disease, and he is in excellent health. Endobronchial biopsy confirms that the lesion is malignant but the organ of origin cannot be determined. What should he be given?