Adequacy of Lymph Node Yield for Papillary Thyroid Cancer: An Analysis of 23,131 Patients.

BACKGROUND: Threshold numbers for defining adequacy of lymph node (LN) yield have been determined for evaluation of occult nodal disease during papillary thyroid cancer (PTC) surgery. This study assesses the prevalence of adequate LN yield and estimates its association with patient clinicopathologic characteristics. MATERIALS AND METHODS: Adult patients with cN1 pT1b or pT2 and cN0 or cN1 pT3 M0 PTC ≥1 cm who received surgery with ≥1 LN resected were identified from the National Cancer Database, 2004-2015. Adequate yield was defined as removing ≥6, 9, and 18 LNs for pT1b, pT2, and pT3 stages, respectively, based on recently published literature. Univariable and multivariable logistic regression were used to determine factors associated with adequate yield. RESULTS: A total of 23,131 patients were included; 7544 (32.6%) had adequate LN yield. Rate of adequate yield increased from 19.9% to 36.6% over time. After adjustment, patients at academic facilities were more likely to have adequate yield than those at community centers [OR 1.94 (95% CI 1.55-2.41), P < 0.001]. Patients with more advanced tumors were less likely to have adequate yield (pT1b: 75.9% versus pT2: 64.5% versus pT3: 24.6% adequate LN yield, P < 0.001). Patients with adequate LN yield were 0.89 times likely to receive radioactive iodine compared with those with inadequate yield [OR 0.98 (95% CI 0.81-0.98), P = 0.02]. CONCLUSIONS: The rate of adequate LN yield has increased over time, but only a minority of lymphadenectomies performed for PTC can be defined as adequate. Disparities still exist based on patient and facility characteristics; patients with more advanced tumors appear less likely to have adequate LN yield.

Factors Affecting the Obliteration Rate of Intracranial Aneurysms Treated with a Single Pipeline Embolization Device.

OBJECTIVE: To evaluate the clinical and angiographic outcomes of intracranial aneurysm treatment using a single Pipeline embolization device (PED), and to evaluate the factors affecting aneurysm obliteration rate. METHODS: The demographic characteristics and anatomic features of 58 aneurysms in 47 patients treated with a single PED were reviewed retrospectively. All aneurysms treated with a PED at a single center and with follow-up angiograms for at least 6 months were included in this study. RESULTS: The overall rate of complete and near-complete occlusion was 84% (49 of 58) after a mean follow-up period of 18.3 months. The rate of complete aneurysm obliteration was lower in aneurysms with an arterial branch arising from the aneurysm neck compared with aneurysms without an arterial branch (13% [1 of 8] vs. 68% [34 of 50]; P = 0.0075). The overall rate of complete and near-complete aneurysm occlusion was 90% (45 of 50) in aneurysms without an arterial branch arising from its neck. There were no statistically significant associations between obliteration rate and aneurysm neck width, size, or type, or history of previous coil embolization. CONCLUSIONS: Our data suggest that a single PED is sufficient to induce complete or near-complete obliteration of most aneurysms. The presence of a branching artery arising from the aneurysm neck is highly predictive of incomplete occlusion after treatment with a single PED.

Projecting Survival in Papillary Thyroid Cancer: A Comparison of the Seventh and Eighth Editions of the American Joint Commission on Cancer/Union for International Cancer Control Staging Systems in Two Contemporary National Patient Cohorts.

BACKGROUND: This study aims to compare the seventh and eighth editions of the American Joint Commission on Cancer/Union for International Cancer Control (AJCC/UICC) tumor, node, metastasis staging system for patients with papillary thyroid cancer (PTC) in two national patient cohorts. METHODS: Adult PTC patients undergoing surgery were selected from the Surveillance, Epidemiology and End Results (SEER) program (2004-2012) and the National Cancer Database (2004-2012). Staging criteria for the seventh and eighth AJCC/UICC editions were applied separately to each cohort. Survival probabilities were estimated using the Kaplan-Meier method. Multivariable Cox proportional hazards models were used to estimate the association of stage with survival in both settings. The Akaike information criterion was used to assess model performance. RESULTS: About 23% of patients were downstaged from the seventh to the eighth edition in SEER, while 24% were downstaged in the National Cancer Database. Disease-specific survival (DSS) and overall survival (OS) were significantly related to stage at diagnosis when using both the seventh and eighth editions of the AJCC/UICC staging system (p < 0.001). Patients classified into higher stages (III and IV) in the eighth edition showed a worse prognosis than those classified into similar stages in the seventh edition. After adjustment, PTC stages as defined by both editions were significantly associated with DSS and OS. With respect to both DSS and OS, the eighth edition PTC model appeared to be a better fit to the data (smaller Akaike information criterion values) compared to the seventh edition. CONCLUSION: Based on these large contemporary national cohorts, the eighth edition AJCC/UICC tumor, node, metastasis classification for PTC is superior to the seventh edition for predicting survival.