Outcome of long standing solitary thyroid nodules.

We investigated the outcome of long standing palpable solitary thyroid nodules by surveying 441 patients and examining 140 patients who had untreated thyroid nodules for 15 +/- 4.5 years. In our clinical survey, the most common outcome was disappearance of the thyroid nodule (38.3%). Also a significant number of patients (36.3%) underwent surgery in other hospitals. Five (1.1%) patients died of thyroid cancer. When thyroid nodules were re-examined, most nodules indeed decreased in size or disappeared; however, 13% of nodules increased in size. Ultrasound of the nodules showed that most solitary nodules were multiple and partially cystic and solid. There was an increased incidence of calcification in long standing nodules. Thyroid cancer was found by fine needle aspiration biopsy in 26.3% of enlarging nodules and 6.4% of nodules without changing size. The risk of cancer decreased when the size of the nodule decreased. A total of 15 patients with suspicion of malignancy underwent surgery. Surgical procedures were lobectomy, near total thyroidectomy, or resection of nodules with or without modified neck dissection. Seven patients had papillary carcinoma and 2 patients with benign cytology had microscopically evident papillary carcinoma. In our study, the majority of palpable solitary thyroid nodules tended to decrease in size; these nodules do not require treatment. Enlarging solid nodules are a definite risk for thyroid cancer. If the size of the nodule remains the same, judicious approach with fine needle aspiration biopsy is needed.