Multifocal papillary thyroid carcinoma--a consensus report of the European Society of Endocrine Surgeons (ESES).

BACKGROUND: Multifocal papillary thyroid carcinoma (MPTC) has been reported in literature in 18-87 % of cases. This paper aims to review controversies in the molecular pathogenesis, prognosis, and management of MPTC. METHODS: A review of English-language literature focusing on MPTC was carried out, and analyzed in an evidence-based perspective. Results were discussed at the 2013 Workshop of the European Society of Endocrine Surgeons devoted to surgery of thyroid carcinoma. RESULTS: Literature reports no prospective randomized studies; thus, a relatively low level of evidence may be achieved. CONCLUSIONS: MPTC could be the result of either true multicentricity or intrathyroidal metastasis from a single malignant focus. Radiation and familial nonmedullary thyroid carcinoma are conditions at risk of MPTC development. The prognostic importance of multifocal tumor growth in PTC remains controversial. Prognosis might be impaired in clinical MPTC but less or none in MPTC <1 cm. MPTC can be diagnosed preoperatively by FNAB and US, with low sensitivity for MPTC <1 cm. Total or near-total thyroidectomy is indicated to reduce the risk of local recurrence. Prophylactic central node dissection should be considered in patients with total tumor diameter >1 cm, or in cases with high number of cancer foci. Completion thyroidectomy might be necessary when MPTC is diagnosed after less than near-total thyroidectomy. Radioactive iodine ablation should be considered in selected patients with MPTC at increased risk of recurrence or metastatic spread.

Iodine content and distribution in extratumoral and tumor thyroid tissue analyzed with X-ray fluorescence and time-of-flight secondary ion mass spectrometry.

BACKGROUND: The thyroid's ability to enrich and store iodine has implications for thyroid cancer genesis, progression, and treatment. The study objective was to investigate thyroid iodine content (TIC) in tumoral and extratumoral tissue in patients with papillary thyroid cancer (PTC) as opposed to thyroid healthy controls using two different techniques: X-ray fluorescence (XRF) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). METHODS: Tissue samples from 10 patients with normal thyroids and 7 patients with PTC were collected. TIC was quantified with XRF, and the iodine stores were located on a histological level with TOF-SIMS. RESULTS: Mean TIC in controls was 0.6 mg/mL (range 0.3-1.2 mg/mL). For the cancer patients, the mean TIC was 0.8 mg/mL (range 0.2-2.3 mg/mL) in extratumoral thyroid tissue, but no iodine was detected in the tumors. TOF-SIMS investigation of the PTC patients showed significantly higher TIC in extratumoral tissue than in tumoral tissue. Iodine in the extratumoral tissue was predominantly located in the follicle lumen with a variation in concentration among follicles. CONCLUSIONS: XRF and TOF-SIMS are two complementary methods for obtaining insight into content and localization of iodine in the thyroid. XRF can be used in vitro or in vivo on a large number of samples or patients, respectively. TOF-SIMS on the other hand provides detailed images of the iodine location. The combined information from the two methods is of value for further studies on iodine metabolism in thyroid malignancy.