The Implication of Lymph Node Metastasis on Survival in Patients with Well-Differentiated Thyroid Cancer

Abstract

Though survival for well-differentiated thyroid cancer is very good, specific populations suffer greater recurrence and mortality. Defining these cohorts can significantly influence prognosis and extent of treatment. This study, using a large, multi-institutional database, seeks to determine how the presence of lymph node disease in patients with well-differentiated thyroid cancer affects outcome. The Surveillance, Epidemiology, and End Results (SEER) database is a large-scale sample of 14 per cent of the U.S. population. It was used to identify patients with papillary and follicular thyroid carcinomas and identify the prognostic implications of lymph node metastasis. Additional factors, including presence of metastasis, age, and tumor size, were compared using multivariate and χ2 analyses. Of 19,918 patients identified, lymph node status was known for 9,904 (49.7%). On multivariate analysis, age >45 years, presence of distant metastasis, large tumor size, and lymph node involvement significantly predicted poor outcome. Overall survival at 14 years was 82 per cent for node negative and 79 per cent for node positive patients ( P < 0.05). This study shows that the survival of patients with well-differentiated thyroid cancer is adversely affected by lymph node metastases. The optimum treatment for this cohort needs further delineation, as particular populations are at greater risk of recurrence and death.

Papillary thyroid carcinoma nodal surgery directed by a preoperative radiographic map utilizing CT scan and ultrasound in all primary and reoperative patients

“…In fact, lymph node status has been omitted from prognostic schemes which include age, distant metastases, extent of disease, and size (AMES), patient age, tumor grade, tumor extent, and tumor size (AGES), and metastases, patient age, completeness of resection, local invasion, and tumor size (MACIS) . Although, 2 recent Surveillance, Epidemiology, and End Results database reports suggest that nodal disease is in fact a determinant of tumor‐related survival in patients over 45 years of age, clearly the bulk of prognostic importance for PTC nodes centers on recurrence.…”

Predictive value of the Delphian and level VI nodes in papillary thyroid cancer

“…In recent times, lymph node involvement in PTC was not included in any of the prognostic staging systems as it was not considered to influence survival. However, it is known from current data that central node metastases, the number of lymph node metastases and locoregional recurrence are all adverse prognostic factors in thyroid cancer 10,11,14,15,17–19,35–37 . Similarly, it is known that central and lateral lymph node metastases are associated with higher rates of recurrence 9,10,12,13,16,20,36,38,39 .…”

Disease outcomes and nodal recurrence in patients with papillary thyroid cancer and lateral neck nodal metastases

“…Despite these low mortality rates, nodal recurrence occurs in up to 20% of patients at 10 years and 30% of patients at 30 years . Some studies have suggested that patients with involved lateral neck lymph nodes at the time of diagnosis have lower rates of disease‐free survival and higher rates of lateral neck nodal recurrence . However, the prognostic influence of nodal metastases in PTC remains controversial …”

“…A number of large studies have investigated the impact of lymph node metastases on outcome in patients with PTC . The majority of these studies have suggested that the presence of nodal metastasis is associated with inferior disease‐free survival; however, one of these studies found that the presence of nodal metastases conferred a negative prognostic impact only in patients aged >45 years .…”