Comparing High and Low-Dose Radio-Iodine Therapy in Thyroid Remnant Ablation Among Intermediate and Low-Risk Papillary Thyroid Carcinoma Patients—Single Centre Experience

The role of Iodine-131 therapy is well established as an adjuvant therapy and for thyroid remnant ablation in differentiated thyroid cancer (DTC); however controversy still exists regarding its appropriate dose. Purpose of this study was to compare the effectiveness of low-dose and high-dose Iodine-131 ablation therapies in low- and intermediate-risk PTC patients. Eighty-four patients were divided equally into Group I: Ablated with high dose of Iodine-131 and Group II: Ablated with low dose of Iodine-131. Iodine-131 WBS, serum TG levels and USG neck of all patients were performed at first presentation, 6 months, 1 year, and 2 years follow up. Results are as follows: Group I: 64%, 72%, and 76% intermediate-risk patients were disease free at the follow up intervals of 6 months, 1 year, and 2 years, respectively. Similarly 70%, 82%, and 82% low-risk patients were disease free at above mentioned intervals. Group II: 56%, 60%, and 64% were disease free among intermediate-risk patients while percentage of disease free low-risk patients was 70%, 76%, and 76% at follow up intervals. Low dose of radioactive Iodine-131 was found as effective as high dose in thyroid remnant ablation of PTC patients.

Radioiodine in Differentiated Thyroid Carcinoma: Do We Need Diagnostic Pre-Ablation Iodine-123 Scintigraphy to Optimize Treatment?

Changing insights regarding radioiodine (I-131) administration in differentiated thyroid carcinoma (DTC) stir up discussions on the utility of pre-ablation diagnostic scintigraphy (DxWBS). Our retrospective study qualitatively and semi-quantitatively assessed posttherapy I-131 whole-body scintigraphy (TxWBS) data for thyroid remnant size and metastasis. Findings were associated with initial treatment success after nine months, as well as clinical, histopathological, and surgical parameters. Possible management changes were addressed. A thyroid remnant was reported in 89 of 97 (92%) patients, suspicion of lymph node metastasis in 26 (27%) and distant metastasis in 6 (6%). Surgery with oncological intent and surgery by two dedicated thyroid surgeons were independently associated with a smaller remnant. Surgery at a community hospital, aggressive tumor histopathology, histopathological lymph node metastasis (pN1) and suspicion of new lymph node metastasis on TxWBS were independently associated with an unsuccessful treatment. Thyroid remnant size was unrelated to treatment success. All 13 pN1 patients with suspected in situ lymph node metastases on TxWBS had an unsuccessful treatment, opposite 19/31 (61%) pN1 patients without (p = 0.009). Pre-ablative knowledge of these TxWBS findings had likely influenced management in 48 (50%) patients. Additional pre-ablative diagnostics could optimize patient-tailored I-131 administration. DxWBS should be considered, especially in patients with pN1 stage or suspected in situ lymph node metastasis. Dependent on local surgical expertise, DxWBS is not recommended to evaluate thyroid remnant size.

PROBABILITY OF CANCER DETECTION DURING REPEATED OPERATIONS IN PATIENTS WITH BENIGN THYROID DISEASES

Introduction. Suspected malignant growth in patients with recurrent goiter is one of the main causes of repeated operations. Focuses of carcinoma can be detected in patients operated on for multinodular goiter with compression of the organs of the neck, recurrent diffuse toxic goiter. Objective of investigation is to assess the risk of a malignant lesion of the thyroid remnant in patients with recurrent goiter, to justify the surgical tactics in this group of patients. Material and methods. In the St. Petersburg Center of Endocrine Surgery and Oncology 28138 patients with various thyroid diseases were operated on for the period from 1973 till 2016. Results. In a retrospective analysis of the group consisting of 1106 patients with recurrent goiter, a new thyroid disease was detected in 156 (14.1%) cases. Thyroid cancer in thyroid remnant was detected in 57 (36.5%) cases or 5.2% of all the patients with recurrent goiter. The work describes the risk of malignant lesion of the thyroid remnant in patients with recurrent goiter and surgical tactics in this group of patients. Conclusion. Cancer of the thyroid gland, as a new disease of the thyroid remnant, in patients previously operated on for benign thyroid pathology, is found in 5.2% of observations. The possibilities of fine-needle aspiration biopsy in this group are reduced. Active surgical tactics in cases of multinodular transformation of the thyroid remnant is justified. The operation of choice is reresection up to thyroidectomy. Careful intraoperative study of removed tissue and close cooperation with the morphological service helps to reduce the number of diagnostic and tactical errors in patients with both recurrent and ordinary multi-node goiter.

Cervical thyroid remnant consistent with papillary carcinoma as an incidental finding in a patient with benign total thyroidectomy ten years prior

Background: Differential diagnosis of a cervical lesion corresponding with papillary thyroid carcinoma (PTC) after benign total thyroidectomy can be a real challenge. Methods: A cervical thyroid remnant compatible with papillary carcinoma was incidentally found ten years after total thyroidectomy for a non-functional multinodular goitre. Histological analysis of fine needle puncture aspiration (FNPA) was highly suggestive for PTC. Surgical excision of the cervical lesion was performed. Specimen study demonstrated a classic variant of PTC contacting a peripheral margin, applying ablative treatment with radioactive iodine postoperatively. Results: The patient did not present signs of recurrence during follow-up. Small thyroid remnants after benign thyroidectomy are often left behind, although their risk of malignancy is exceptional. Conclusions: It is important to individualize therapeutic approach when facing this rare entity. We decided to treat the patient by removing the lesion followed by ablation therapy with successful results. PTC: Papillary thyroid carcinoma FNPA: Fine needle puncture aspiration