Clinicopathologic characteristics of incidental thyroid carcinoma in euthyroid patients receiving total thyroidectomy for multinodular goiter: A retrospective cohort study

Abstract

Background: Total thyroidectomy is the treatment of choice for multinodular goiter (MNG). In some of these cases, incidental thyroid cancer (ITC) is detected postoperatively. Papillary thyroid microcarcinoma (PTMC), the most common type of ITC, has clinical factors and pathologic similarities with ITC that have not been well clarified previously. We investigated the incidence and characteristics of ITC and PTMC in euthyroid patients undergoing total thyroidectomy for MNG. Methods: We retrospectively investigated the data of 151 euthyroid patients who underwent total thyroidectomy for MNG between January 2016 and December 2020. Patients with PTMC were then selected from among those with ITC for further data analysis.Results: The incidence rates of ITC and PTMC were 31.1% (47/151) and 21.1% (32/151), respectively. The mean age of patients with ITC was 52.8 ± 11.7 years, which was younger than that of patients with benign MNG (57.2 ± 12.5 years, p < 0.05). Bilateral cancer was observed in 17 patients with ITC (17/47, 36.2%) and nine with PTMC (9/32, 28.1%). The numbers of patients in the ITC and PTMC groups whose cancer was not on the side comprising the dominant tumor were 15 (15/47, 31.9%) and 13 (13/32, 40.6%), respectively. The multivariate analysis demonstrated that younger age was a clinical factor associated with ITC and PTMC. Conclusion: Younger age is a clinical factor for ITC and PTMC. We recommend taking considering clinical factors and pathologic characteristics of ITC and PTC when considering total thyroidectomy in euthyroid patients with MNG.

Comparison of outcome of conventional suture ligation versus ligasure vessel sealing in patients undergoing total thyroidectomy for multinodular goiter.

“…The post-operative hemorrhage in the Ligasure small jaw group was 39.80 ± 20.50 ml against 45.37±21.37 ml in the conventional method group. 25 In terms of blood loss Habash et al showed contrary findings to our study. Hemorrhage during surgery was assessed to be 42.13 ± 3.15 ml in Ligasure group and 73.50 ± 3.66 ml in conventional suturing group.…”

An Indeterminate for Malignancy FNA Report Does Not Increase the Surgical Risk of Incidental Thyroid Carcinoma

“…In the PTMC subset, Vasileiadis et al and Chen et al detected bilateral cancer foci in 19.4% and 28.1%, respectively, similar to the value found in our study (18.2%, 4/22) [ 29 , 36 ]. Finally, larger PTMCs seem more aggressive; hence, different diameters have been proposed as cut-off thresholds to distinguish different clinical courses [ 9 , 39 , 40 ].…”

“…Moreover, this experience demonstrated a similar incidence of ITCs in the subset of cytological indeterminate thyroid nodules (46.8%, 22/47) as compared to the general population (45.2%, 127/281), suggesting that the coexistence of a class III/IV nodule does not increase the risk of having an ITC after surgery. Similarly, Chen et al found 41.2% of ITCs among BSRTC category III nodules [ 36 ]. Nonetheless, the evidence-based cancer risk in cytological categories III–IV turned out to be higher as compared to the expected risk rates reported in the BSRTC system (26.5% vs. 5–15% for class III and 31.3% vs. 15–30% for class IV) [ 12 ].…”

“…Concerning the demographic features, we found female sex to be prevalent (72.7%), and most patients (68.1%) were aged >55 years (per AJCC age groups), in accordance with the literature ( Table S2 ). Provenzale et al found that incidental PTMCs were multifocal in 76.1% of cases and that they were significantly smaller (4 vs. 9 mm) compared to non-incidental PTMCs, while Chen et al found a 34.4% multifocality rate in incidental PTMCs [ 36 , 38 ]. Evranos et al analyzed 900 final histopathological diagnoses of thyroid cancer, comparing patients with incidental and non-incidental carcinomas, finding in the former group significant lower cancer multifocality [ 2 ].…”

“…A middle approach may be represented by lobectomy, performed for incidental tumors at a stage below pT1b (i.e., <1 cm in greatest dimension and limited to the thyroid, according to the AJCC 8th edition) or else for unifocal small (<1.5 cm) tumors with no evidence of extrathyroidal extension or lymph node metastases, in patients without a personal history of neck irradiation or family history of thyroid cancer and who are unlikely to undergo postoperative radioactive iodine therapy [ 8 , 17 , 45 ]. Interestingly, Kaliszewski et al found comparable ITC prevalence rates between patients who underwent radical and subtotal surgery, while Chen et al found that lobectomy is related to a 9.9% ITC missing rate [ 21 , 36 ]. In our experience, 95.4% (21/22) of patients underwent total thyroidectomy, and performing hemi-thyroidectomy would lead to 50% missed cancer diagnoses (31.8% due to a cancer nodule in the other lobe and 18.2% due to bilateral cancer foci).…”