To investigate the prognostic value of BRAF V600E mutation for the recurrence of papillary thyroid cancer (PTC).
This was a retrospective multicenter study of the relationship between BRAF V600E ...mutation and recurrence of PTC in 2,099 patients (1,615 women and 484 men), with a median age of 45 years (interquartile range IQR, 34 to 58 years) and a median follow-up time of 36 months (IQR, 14 to 75 months).
The overall BRAF V600E mutation prevalence was 48.5% (1,017 of 2,099). PTC recurrence occurred in 20.9% (213 of 1,017) of BRAF V600E mutation-positive and 11.6% (125 of 1,082) of BRAF V600E mutation-negative patients. Recurrence rates were 47.71 (95% CI, 41.72 to 54.57) versus 26.03 (95% CI, 21.85 to 31.02) per 1,000 person-years in BRAF mutation-positive versus -negative patients (P < .001), with a hazard ratio (HR) of 1.82 (95% CI, 1.46 to 2.28), which remained significant in a multivariable model adjusting for patient sex and age at diagnosis, medical center, and various conventional pathologic factors. Significant association between BRAF mutation and PTC recurrence was also found in patients with conventionally low-risk disease stage I or II and micro-PTC and within various subtypes of PTC. For example, in BRAF mutation-positive versus -negative follicular-variant PTC, recurrence occurred in 21.3% (19 of 89) and 7.0% (24 of 342) of patients, respectively, with recurrence rates of 53.84 (95% CI, 34.34 to 84.40) versus 19.47 (95% CI, 13.05 to 29.04) per 1,000 person-years (P < .001) and an HR of 3.20 (95% CI, 1.46 to 7.02) after adjustment for clinicopathologic factors. BRAF mutation was associated with poorer recurrence-free probability in Kaplan-Meier survival analyses in various clinicopathologic categories.
This large multicenter study demonstrates an independent prognostic value of BRAF V600E mutation for PTC recurrence in various clinicopathologic categories.
Purpose For the past 65 years, patient age at diagnosis has been widely used as a major mortality risk factor in the risk stratification of papillary thyroid cancer (PTC), but whether this is ...generally applicable, particularly in patients with different BRAF genetic backgrounds, is unclear. The current study was designed to test whether patient age at diagnosis is a major mortality risk factor. Patients and Methods We conducted a comparative study of the relationship between patient age at diagnosis and PTC-specific mortality with respect to BRAF status in 2,638 patients (623 men and 2,015 women) with a median age of 46 years (interquartile range, 35 to 58 years) at diagnosis and a median follow-up time of 58 months (interquartile range, 26 to 107 months). Eleven medical centers from six countries participated in this study. Results There was a linear association between patient age and mortality in patients with BRAF V600E mutation, but not in patients with wild-type BRAF, in whom the mortality rate remained low and flat with increasing age. Kaplan-Meier survival curves rapidly declined with increasing age in patients with BRAF V600E mutation but did not decline in patients with wild-type BRAF, even beyond age 75 years. The association between mortality and age in patients with BRAF V600E was independent of clinicopathologic risk factors. Similar results were observed when only patients with the conventional variant of PTC were analyzed. Conclusion The long-observed age-associated mortality risk in PTC is dependent on BRAF status; age is a strong, continuous, and independent mortality risk factor in patients with BRAF V600E mutation but not in patients with wild-type BRAF. These results question the conventional general use of patient age as a high-risk factor in PTC and call for differentiation between patients with BRAF V600E and wild-type BRAF when applying age to risk stratification and management of PTC.
Papillary thyroid microcarcinoma is a subtype of thyroid cancer that may be managed with active surveillance rather than immediate surgery. Active surveillance decreases complication rates and may ...decrease health care costs. This study aims to analyze complication rates of thyroid surgery, papillary thyroid microcarcinoma recurrence, and survival rates. Additionally, the costs of surgery versus hypothetic active surveillance for papillary thyroid microcarcinoma are compared in an Australian cohort.
Papillary thyroid microcarcinoma patients were included from a prospectively collected surgical cohort of patients treated for papillary thyroid cancer between 1985 and 2017. The primary outcomes were the complications of thyroid surgery, recurrence-free survival, overall survival, and cost of surgical treatment and active surveillance.
In a total of 349 patients with papillary microcarcinoma with a median age of 48 years (range, 18–90 years), the permanent operative complications rate was 3.7%. Postoperative radioactive iodine did not decrease recurrence-free survival (P = .3). The total cost of surgical treatment was $10,226 Australian dollars, whereas hypothetic active surveillance was at a yearly cost of $756 Australian dollars. Estimated cost of surgical papillary thyroid microcarcinoma treatment was equivalent to the cost of 16.2 years of active surveillance.
Surgery may have a long-term economic advantage for younger Australian patients with papillary thyroid microcarcinoma who are likely to require more than 16.2 years of follow-up in an active surveillance scheme.
Abstract
Context
Multifocality is often treated as a risk factor for papillary thyroid cancer (PTC), prompting aggressive treatments, but its prognostic value remains unestablished.
Objective
To ...investigate the role of tumor multifocality in clinical outcomes of PTC.
Methods
Multicenter study of the relationship between multifocality and clinical outcomes of PTC in 2638 patients (623 men and 2015 women) with median interquartile range (IQR) age of 46 (35 to 58) years and median (IQR) follow-up time of 58 (26 to 107) months at 11 medical centers in six countries. Surveillance, Epidemiology and End Results (SEER) data were used for validation.
Results
Disease recurrence in multifocal and unifocal PTC was 198 of 1000 (19.8%) and 221 of 1624 (13.6%) (P < 0.001), with a hazard ratio of 1.55 95% confidence interval (CI), 1.28 to 1.88, which became insignificant at 1.13 (95% CI, 0.93 to 1.37) on multivariate adjustment. Similar results were obtained in PTC variants: conventional PTC, follicular-variant PTC, tall-cell PTC, and papillary thyroid microcarcinoma. There was no association between multifocality and mortality in any of these PTC settings, whereas there was a strong association between classic risk factors and cancer recurrence or mortality, which remained significant after multivariate adjustment. In 1423 patients with intrathyroidal PTC, disease recurrence was 20 of 455 (4.4%) and 41 of 967 (4.2%) (P = 0.892) and mortality was 0 of 455 (0.0%) and 3 of 967 (0.3%) (P = 0.556) in multifocal and unifocal PTC, respectively. The results were reproduced in 89,680 patients with PTC in the SEER database.
Conclusions
Tumor multifocality has no independent risk prognostic value in clinical outcomes of PTC; its indiscriminate use as an independent risk factor, prompting overtreatments of patients, should be avoided.
Despite common belief, this study shows no independent role of multifocality in clinical outcomes of PTC; its indiscriminate use as a risk factor, prompting overtreatment, should be avoided.
How lymph node metastasis (LNM)-associated mortality risk is affected by BRAF V600E in papillary thyroid cancer (PTC) remains undefined.
To study whether BRAF V600E affected LNM-associated mortality ...in PTC.
We retrospectively analyzed the effect of LNM on PTC-specific mortality with respect to BRAF status in 2638 patients (2015 females and 623 males) from 11 centers in 6 countries, with median age of 46 interquartile range (IQR) 35-58 years and median follow-up time of 58 (IQR 26-107) months.
Overall, LNM showed a modest mortality risk in wild-type BRAF patients but a strong one in BRAF V600E patients. In conventional PTC (CPTC), LNM showed no increased mortality risk in wild-type BRAF patients but a robustly increased one in BRAF V600E patients; mortality rates were 2/659 (0.3%) vs 4/321 (1.2%) in non-LNM vs LNM patients (P = 0.094) with wild-type BRAF, corresponding to a hazard ratio (HR) (95% CI) of 4.37 (0.80-23.89), which remained insignificant at 3.32 (0.52-21.14) after multivariate adjustment. In BRAF V600E CPTC, morality rates were 7/515 (1.4%) vs 28/363 (7.7%) in non-LNM vs LNM patients (P < 0.001), corresponding to an HR of 4.90 (2.12-11.29) or, after multivariate adjustment, 5.76 (2.19-15.11). Adjusted mortality HR of coexisting LNM and BRAF V600E vs absence of both was 27.39 (5.15-145.80), with Kaplan-Meier analyses showing a similar synergism.
LNM-associated mortality risk is sharply differentiated by the BRAF status in PTC; in CPTC, LNM showed no increased mortality risk with wild-type BRAF but a robust one with BRAF mutation. These results have strong clinical relevance.
Background
Medullary thyroid carcinoma (MTC) can be targeted with tyrosine kinase inhibitors (TKIs). We aimed to report the outcomes of surgically managed MTC and to evaluate the impact of TKI use on ...patient survival.
Methods
Consecutive patients treated surgically for MTC from 1986 to 2020 were identified from a prospectively collected database and were compared on the basis of stage at operation and TKI use. The primary outcome was overall survival (OS).
Results
Among 154 patients with a median age of 52 years, 40% presented with stage I/II disease and 60% presented with advanced (stage III or IV) disease. During a median follow-up of 7.5 years, 21% received TKIs for systemic disease. Those presenting with advanced disease were more likely to receive a TKI (31% vs. 7%), present with tumor invasion of the recurrent laryngeal nerve (RLN; 12% vs. 0%) and undergo reoperation (42% vs. 23%) compared with stage I–II patients. For the 11 patients found to have invasion of the RLN, five had preoperative functional vocal cords. Five-year OS was 84% for advanced disease, and stage IV patients who received TKIs had a median survival of 21 years, versus 15 years for those who did not (
p
= 0.3).
Conclusions
Surgery achieves long-term survival for patients with advanced disease, however these patients are at greater risk of requiring RLN resection due to invasion. A significant OS benefit was not seen for TKI use. For patients with local invasion, neoadjuvant TKI therapy may have a role in reducing local morbidity if confirmed to be of benefit in clinical trials.
BRAF V600E is a prominent oncogene in papillary thyroid cancer (PTC), but its role in PTC-related patient mortality has not been established.
To investigate the relationship between BRAF V600E ...mutation and PTC-related mortality.
Retrospective study of 1849 patients (1411 women and 438 men) with a median age of 46 years (interquartile range, 34-58 years) and an overall median follow-up time of 33 months (interquartile range, 13-67 months) after initial treatment at 13 centers in 7 countries between 1978 and 2011.
Patient deaths specifically caused by PTC.
Overall, mortality was 5.3% (45/845; 95% CI, 3.9%-7.1%) vs 1.1% (11/1004; 95% CI, 0.5%-2.0%) (P < .001) in BRAF V600E-positive vs mutation-negative patients. Deaths per 1000 person-years in the analysis of all PTC were 12.87 (95% CI, 9.61-17.24) vs 2.52 (95% CI, 1.40-4.55) in BRAF V600E-positive vs mutation-negative patients; the hazard ratio (HR) was 2.66 (95% CI, 1.30-5.43) after adjustment for age at diagnosis, sex, and medical center. Deaths per 1000 person-years in the analysis of the conventional variant of PTC were 11.80 (95% CI, 8.39-16.60) vs 2.25 (95% CI, 1.01-5.00) in BRAF V600E-positive vs mutation-negative patients; the adjusted HR was 3.53 (95% CI, 1.25-9.98). When lymph node metastasis, extrathyroidal invasion, and distant metastasis were also included in the model, the association of BRAF V600E with mortality for all PTC was no longer significant (HR, 1.21; 95% CI, 0.53-2.76). A higher BRAF V600E-associated patient mortality was also observed in several clinicopathological subcategories, but statistical significance was lost with adjustment for patient age, sex, and medical center. For example, in patients with lymph node metastasis, the deaths per 1000 person-years were 26.26 (95% CI, 19.18-35.94) vs 5.93 (95% CI, 2.96-11.86) in BRAF V600E-positive vs mutation-negative patients (unadjusted HR, 4.43 95% CI, 2.06-9.51; adjusted HR, 1.46 95% CI, 0.62-3.47). In patients with distant tumor metastasis, deaths per 1000 person-years were 87.72 (95% CI, 62.68-122.77) vs 32.28 (95% CI, 16.14-64.55) in BRAF V600E-positive vs mutation-negative patients (unadjusted HR, 2.63 95% CI, 1.21-5.72; adjusted HR, 0.84 95% CI, 0.27-2.62).
In this retrospective multicenter study, the presence of the BRAF V600E mutation was significantly associated with increased cancer-related mortality among patients with PTC. Because overall mortality in PTC is low and the association was not independent of tumor features, how to use BRAF V600E to manage mortality risk in patients with PTC is unclear. These findings support further investigation of the prognostic and therapeutic implications of BRAF V600E status in PTC.
We investigated the prognostic value of a range of histologic parameters in medullary thyroid carcinoma (MTC) to design a grading system to predict overall survival. We assessed 76 patients with MTCs ...undergoing primary tumor resection for age, sex, tumor size, vascular space invasion, lymph node metastasis, multiple endocrine neoplasia type 2 (MEN2) status, mitotic count, Ki-67 proliferative index, spindled morphology, sheet-like growth pattern, coagulative necrosis, incipient necrosis, nuclear grade, multinucleation, prominent nucleoli, fibrosis, and amyloid deposition. In addition to the clinical features of age and the diagnosis of MEN2, the only histologic features that significantly predicted reduced overall survival were Ki-67 proliferative index, mitotic count, and the presence of coagulative necrosis. Using a combination of these 3 variables, we propose a 3-tiered grading system based solely on proliferative activity (Ki-67 proliferative index and mitotic count) and necrosis. There were 62 (82%) low-grade MTCs (low proliferative activity, no necrosis), 9 (12%) intermediate grade (low proliferative activity and necrosis present, or intermediate proliferative activity and no necrosis), and 5 (7%) high grade (intermediate proliferative activity and necrosis present, or high proliferative activity with or without necrosis). The mean overall survival was 193, 146, and 45 months, respectively (P=0.0001) for the 3 grades. The grading system remained prognostic when controlled for other factors associated with survival including age and known MEN2 syndrome. We conclude that this proposed grading system, which uses only a combination of proliferative activity (Ki-67 index, mitotic count) and coagulative necrosis, is a strong predictor of overall survival in MTC.