Clinical presentation and outcome in patients treated for papillary and follicular carcinoma of the thyroid : patterns in Johannesburg

Full text: Purpose: To look at the clinical presentation and treatment outcome of patients with papillary thyroid carcinoma (PTC) and those with follicular thyroid carcinoma (FTC) in our institution. Methods: The records of all patients with papillary or follicular thyroid carcinoma seen at our institution were retrieved. Patients were excluded from this study if they underwent thyroid surgery outside a teaching hospital or presented to us more than 6 months post surgery, had deep external beam therapy (DXT) following surgery or a follow up of less than 3 years. This left clinical data and treatment outcomes of 140 patients available for a retrospective review. Results: One hundred and seventeen patients were females and 23 were males (5.1:1) with a median follow up of 10,5 years. The differences noted were as follow: there was a higher incidence of PTC than FTC (2.9:1); patients with PTC were younger at presentation (mean age 40 vs 49); more patients with PTC had metastases (60% vs 40%) and were much younger at presentation as compared to those with FTC (mean age 38 vs 63); at presentation eighty percent of FTC metastases were localized in bones whereas 60% of PTC metastases went to the lungs and 36% were confined to local lymph nodes. Similar pattern was found in those who developed metastases later. A significant percentage of ablation failure (41% vs 59% success rate) after the first high dose (2.96-3.7 GBq) of radioactive iodine (RAI) was noted. The total success rate increased to 80% after the second dose of RAI (3.7- 7.4 GBq). The majority of the patients ablated by the second dose had PTC and most had inadequate initial surgery ranging from unilateral lobectomy (10 patients), subtotal thyroidectomy (10 patients), and bilateral lobar resection (1 ). Conclusion: The predominance of PTC over FCT may indicate the conversion to an iodine repletion state in the country as a whole. Similar studies in other regions seem necessary to support this statement. The high ablation failure may be related to poor first surgery. Therefore a near total thyroidectomy should be recommended for both histological types to minimize the likelihood of locoregional recurrence and improve the probability of cure. (author)