Association of Multifocality With Prognosis of Papillary Thyroid Carcinoma

Abstract

hyroid cancer is the ninth most frequent cancer worldwide, and its incidence has risen dramatically. 1,2 There were 567 233 patients with newly diagnosed thyroid cancer in 2018, representing 3.1% of all cancer cases worldwide. Papillary thyroid carcinoma (PTC) comprises more than 80% of all thyroid cancers, and is usually associated with an excellent prognosis; 3 however, up to 30% of patients experience significant disease progression, including regional recurrences and distant metastases. [4][5][6] Researchers have tried to identify the patients at high-risk from among the population with favorable outcomes; 7-9 clinicopathological factors, including tumor size, extrathyroidal extension, lymph node metastasis, and multifocality, have been thoroughly evaluated in an effort to predict recurrence and mortality.Multifocality in thyroid cancer is defined as the simultaneous presence of more than 1 tumor focus within the thyroid gland. 10 Multifocality in PTC occurred in 18% to 87% of the cases in the literature. 10,11 Several studies have demonstrated that multifocality is associated with high-risk features of PTC, including aggressive histologic subtype, extrathyroidal extension, lymph node involvement, distant metastasis, and recurrences. 12-14 Some researchers have further demonstrated that multifocal PTCs could decrease overall and cancer-specific survival. 11,15 Other researchers have indicated that patients with multifocal diseases showed a similar clinical course or comparable recurrence rates as those with unifocal disease. [16][17][18] These conflicting results indicate a need IMPORTANCE Multifocality is common in papillary thyroid carcinoma (PTC), but it is unclear whether multifocal tumors are associated with tumor recurrence or cancer-specific survival. OBJECTIVE To compare tumor recurrence rates in patients with multifocal vs unifocal PTCs. DATA SOURCES We searched PubMed, SCOPUS, Web of Science Core Collection, and Cochrane Database of Systematic Reviews for pertinent studies published in English from inception to June 30, 2020. STUDY SELECTION The search strategy yielded 26 studies that compared tumor recurrence in patients with multifocal vs unifocal PTC. DATA EXTRACTION AND SYNTHESIS Data was extracted in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Characteristics of study populations and hazard ratio (HR) of multifocality were independently extracted by 2 investigators. MAIN OUTCOMES AND MEASURESThe primary outcome was tumor recurrence and the secondary outcome was cancer-specific survival. Subgroup analysis of the primary outcome was based on primary tumor size, number of tumor foci, and patient age. RESULTS Among 26 studies with a total of 33 976 patients, recurrence rates were significantly higher in patients with multifocal PTC than in those with unifocal PTC (pooled HR, 1.81; 95% CI, 1.52-2.14). Cancer-specific survival was comparable between the groups (HR, 1.19; 95% CI, 0.85-1.68). In subgroup analyses, the HRs of m...

Nomogram model based on preoperative serum thyroglobulin and clinical characteristics of papillary thyroid carcinoma to predict cervical lymph node metastasis

“…It is typically inert and usually shows excellent prognosis to standardized comprehensive treatments (including surgical resection, iodine ablation, and TSH inhibition therapies) (2). However, such clinical features of PTC as the large size of tumor, extrathyroidal extension (ETE), multifocality, lymph node metastasis (LNM), and distant metastasis (3)(4)(5)(6) still lead to a poor prognosis. As a distinctive risk factor for distant metastasis and postoperative local recurrence (7,8), LNM is prone to early PTC (9,10).…”

Clinical outcomes of multifocal papillary thyroid cancer: A systematic review and meta‐analysis

“…Joseph, 60 Kim 61 and Zhang 62 et al performed meta‐analyses in 2018 and 2021, which reported that multifocality is positively correlated with lymph node metastasis (both in central and lateral compartments), advanced TNM stage and recurrence. Here, we conducted a more comprehensive analysis concerning unfavorable clinicopathologic features and time‐to‐event outcomes result from multifocal PTC, of which should be classified as a higher risk category.…”

Preoperative Ultrasonography in the Evaluation of Suspected Familial Non-Medullary Thyroid Cancer: Are We Able to Predict Multifocality and Extrathyroidal Extension?

“…The debate on whether familiarity can be counted as a risk factor in DTC patients is still ongoing, with some studies reporting more aggressive behavior and a higher rate of recurrence [28][29][30], and other studies finding no differences [31]. Still, the impact of microscopic ETE on disease recurrence is not clear, as some studies reported no difference between patients with and without microscopic ETE [32], while a recent meta-analysis documented an increased risk (with no effect on survival) [33].…”